# data[].attributes.body
flooding is any high flow, overflow, or inundation by water that causes or threatens damage. It occurs due to heavy or prolonged precipitation, snowmelt, thunderstorms, storm surges from hurricanes, structural failures of dams and levees, altered drainage, and land-cover alterations (such as pavement). Major types of flooding are flash flooding, urban flooding, river flooding and coastal flooding. There is an increase in floods due to the rise of sea levels.

# data[].attributes.body
heat waves and extreme weather patterns are increasing. Heat waves are rising, including in 2011 and 2012 due to human causes, such as deforestation and burning fossil fuels

# data[].attributes.body
How will global warming impact fish? Explain: warming temperatures and loss of oxygen will kill hundreds of species of fish. Warmer temps speed up fish' metabolisms, meaning that they will need more oxygen. But, because the seas are warmer, there will be less oxygen to draw. Fish will die and the sizes of remaining fish will shrink as a result.

# data[].attributes.headline
storms prices are increasing due to the damages they cause

# data[].attributes.subject
storms prices are increasing due to the damages they cause

# data[].attributes.headline
cost severe weather is 240 billion dollars and they are estimated 300 million dollars

# data[].attributes.subject
cost severe weather is 240 billion dollars and they are estimated 300 million dollars

# data[].attributes.body
Why is sea Level rise not uniform?

-The amount of (mass) of water, and temperature.
1. To what do scientists attribute the recent accelerated sea level rise?
- Melting sea ice at the poles and thermal expansion.
2. What percentage of the population is threatened by rapid sea level rise?
670 Million people.

# data[].attributes.headline
What are the potential impacts of increased CO2 on agriculture?-elizabeth

# data[].attributes.subject
What are the potential impacts of increased CO2 on agriculture?-elizabeth

# data[].attributes.body
1. increase water use efficiency in crops
2. mitigate (reduce) yield losses\
3. water scarcity
4. increase crop yields by increasing rate of photosynthesis
5. lower levels of transpiration

# data[].attributes.headline
list 4 climate change impacts to livestock

# data[].attributes.subject
list 4 climate change impacts to livestock

# data[].attributes.body
1. reduces fertility and milk production
2. increase of parasites and diseases that affect livestock
3. plants that cows eat have a lower nutritional value, the cows need to eat more
4. increase of pesticides entering the food change due to changes in the veterinary process

# data[].attributes.body
What are two factors that cause sea level rise?

1-  Added water from melting icesheets and glaciers.
2- Expansion of sea waters as they warm.

What is the current sea level rise in mm?
89,6 mm

What is the Rate of change per year?
3.3 mm per year

# data[].attributes.headline
How will climate change affect agricultural pests and diseases?

# data[].attributes.subject
How will climate change affect agricultural pests and diseases?

# data[].attributes.body
Pests and pathogens are weather-dependent, and many thrive in hotter, wetter climates — which is exactly the sort of change that global warming is predicted to create over the coming decades. And how plant pests and diseases will respond to a warming world, and found that their range has been steadily shifting toward both poles, as climate change warms higher latitudes. Also, we can already see the results of some of that pest expansion. Warmer winters have allowed the mountain pine beetle to take hold over a greater swath of the Pacific Northwest, allowing it to spread further and higher, at altitudes that in the past would have been too cold for the insect.

# data[].attributes.body
percent of hurricanes that reach categories 3,4, and 5 are changing.

# data[].attributes.body
Name at least three places that will be under water in an ice-less world.

1. North America- The entire Atlantic seaboard, including the gulf coast, Florida, and the gulf of California.
2. South America- The Paraguay River Basin would wipe out Buenos Aires, coastal Araguaya, and most of Paraguay
3. Asia- Egypt, Alexandria, and Cario will be wiped away

# data[].attributes.headline
What are 3 ways in which vegetation influences weather patterns? -Elizabeth

# data[].attributes.subject
What are 3 ways in which vegetation influences weather patterns? -Elizabeth

# data[].attributes.body
-plants process and release water vapor, used for cloud transformation, absorbs and emits energy used to drive weather.
-plants control the humidity + temperature surrounding their leaves through transpiration
-the process of photosynthesis uses C02, which offsets the amount of greenhouse gases being released in atmosphere

# data[].attributes.body
Identify 3 reasons sea levels are rising-

1. Thermal Expansion- When water heats up, it expands. About half of the sea-level rise over the past 25 years is attributable to warmer oceans simply occupying more space.

2-Melting Glaciers- Large Ice formations melt a bit each summer. Higher temperatures due to global warming has caused more melting and less snowfall.

3-Loss of Greenland and Antarctica's ice sheets- Increased heat is causing the ice sheets to melt faster.

# data[].attributes.headline
How do temperature increases and severe weather impact crops? 

# data[].attributes.subject
How do temperature increases and severe weather impact crops? 

# data[].attributes.body
-increase in temp. and CO2 levels affect crop yields
-sever weather (Such as drought) can ensure that there is no crop growth
-CO2 increases the growth of weeds and lowers the nutritional value of crops
-heat/drought threaten livestock
-parasites and disease increase and affect livestock
-fishery disease outbreaks have been linked to climate change
-timing and reproductions of fish is altered

# data[].attributes.body
How is the pH changing: as dissolved oxygen increases in ppm in the ocean, pH is also increasing. Oceans are becoming more acidic.

What is happening to the coral reefs: Climate change is the greatest threat to coral reefs. Warming oceans, rising sea levels, changes in storm patterns and precipitation, altered ocean currents, and ocean acidification. These all alter the functions of the ecosystem, meaning coral reefs are slowly being destroyed.

3 things that are changing in our oceans due to climate change: First, the amount of heat stored in the ocean has increased substantially since the 1950s. This effects sea level and currents. Second, coastal flooding has become more frequent, especially along the East and Gulf Coasts. Third, the ocean has become more acidic over the past few years because of increased carbon dioxide in the atmosphere.

How is population growth impacting the fishing demand: Increasing population has not only increased the overall demand for fish, but has led to an increase in the base amount of fish needed to feed the population.

How will global warming impact fish? Explain:

# data[].attributes.headline
Flooding - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.subject
Flooding - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.attachment_link.description
The National Climate Assessment summarizes the impacts of climate change on the United States, now and in the future.

# data[].attributes.headline
Heavy downpours - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.subject
Heavy downpours - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.attachment_link.description
The National Climate Assessment summarizes the impacts of climate change on the United States, now and in the future.

# data[].attributes.headline
Drought - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.subject
Drought - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.attachment_link.description
The National Climate Assessment summarizes the impacts of climate change on the United States, now and in the future.

# data[].attributes.body
Heat waves - What does the data SAY? Where is it happening? Why is it happening?

# data[].attributes.attachment_link.description
The National Climate Assessment summarizes the impacts of climate change on the United States, now and in the future.

# data[].attributes.body
List 4 climate change impacts to livestock

# data[].attributes.attachment_link.readable_text
On This Page:

Overview

Agriculture is an important sector of the U.S. economy. The crops, livestock, and seafood produced in the United States contribute more than $300 billion to the economy each year. When food-service and other agriculture-related industries are included, the agricultural and food sectors contribute more than $750 billion to the gross domestic product.

Agriculture and fisheries are highly dependent on the climate. Increases in temperature and carbon dioxide (CO2) can increase some crop yields in some places. But to realize these benefits, nutrient levels, soil moisture, water availability, and other conditions must also be met. Changes in the frequency and severity of droughts and floods could pose challenges for farmers and ranchers and threaten food safety. Meanwhile, warmer water temperatures are likely to cause the habitat ranges of many fish and shellfish species to shift, which could disrupt ecosystems. Overall, climate change could make it more difficult to grow crops, raise animals, and catch fish in the same ways and same places as we have done in the past. The effects of climate change also need to be considered along with other evolving factors that affect agricultural production, such as changes in farming practices and technology.

Impacts on Crops

Crops grown in the United States are critical for the food supply here and around the world. U.S. farms supply nearly 25% of all grains (such as wheat, corn, and rice) on the global market.[4] Changes in temperature, atmospheric carbon dioxide (CO 2), and the frequency and intensity of extreme weather could have significant impacts on crop yields.

For any particular crop, the effect of increased temperature will depend on the crop's optimal temperature for growth and reproduction. In some areas, warming may benefit the types of crops that are typically planted there, or allow farmers to shift to crops that are currently grown in warmer areas. Conversely, if the higher temperature exceeds a crop's optimum temperature, yields will decline.

Higher CO2 levels can affect crop yields. Some laboratory experiments suggest that elevated CO2 levels can increase plant growth. However, other factors, such as changing temperatures, ozone, and water and nutrient constraints, may counteract these potential increases in yield. For example, if temperature exceeds a crop's optimal level, if sufficient water and nutrients are not available, yield increases may be reduced or reversed. Elevated CO2 has been associated with reduced protein and nitrogen content in alfalfa and soybean plants, resulting in a loss of quality. Reduced grain and forage quality can reduce the ability of pasture and rangeland to support grazing livestock.

More extreme temperature and precipitation can prevent crops from growing. Extreme events, especially floods and droughts, can harm crops and reduce yields. For example, in 2010 and 2012, high nighttime temperatures affected corn yields across the U.S. Corn Belt, and premature budding due to a warm winter caused $220 million in losses of Michigan cherries in 2012.

Dealing with drought could become a challenge in areas where rising summer temperatures cause soils to become drier. Although increased irrigation might be possible in some places, in other places water supplies may also be reduced, leaving less water available for irrigation when more is needed.

Many weeds, pests, and fungi thrive under warmer temperatures, wetter climates, and increased CO2 levels. Currently, U.S. farmers spend more than $11 billion per year to fight weeds, which compete with crops for light, water, and nutrients. The ranges and distribution of weeds and pests are likely to increase with climate change. This could cause new problems for farmers' crops previously unexposed to these species.

Though rising CO2 can stimulate plant growth, it also reduces the nutritional value of most food crops. Rising levels of atmospheric carbon dioxide reduce the concentrations of protein and essential minerals in most plant species, including wheat, soybeans, and rice. This direct effect of rising CO2 on the nutritional value of crops represents a potential threat to human health. Human health is also threatened by increased pesticide use due to increased pest pressures and reductions in the efficacy of pesticides.

Impacts on Livestock

Americans consume more than 36 million metric tons of meat and poultry annually. Livestock and poultry account for over half of U.S. agricultural cash receipts, often over $100 billion per year. Changes in climate could affect animals both directly and indirectly.

Heat waves, which are projected to increase under climate change, could directly threaten livestock. In 2011, exposure to high temperature events caused over $1 billion in heat-related losses to agricultural producers. Heat stress affects animals both directly and indirectly. Over time, heat stress can increase vulnerability to disease, reduce fertility, and reduce milk production.

Drought may threaten pasture and feed supplies. Drought reduces the amount of quality forage available to grazing livestock. Some areas could experience longer, more intense droughts, resulting from higher summer temperatures and reduced precipitation. For animals that rely on grain, changes in crop production due to drought could also become a problem.

Climate change may increase the prevalence of parasites and diseases that affect livestock. The earlier onset of spring and warmer winters could allow some parasites and pathogens to survive more easily. In areas with increased rainfall, moisture-reliant pathogens could thrive.

Potential changes in veterinary practices, including an increase in the use of parasiticides and other animal health treatments, are likely to be adopted to maintain livestock health in response to climate-induced changes in pests, parasites, and microbes. This could increase the risk of pesticides entering the food chain or lead to evolution of pesticide resistance, with subsequent implications for the safety, distribution, and consumption of livestock and aquaculture products.

Increases in carbon dioxide (CO2) may increase the productivity of pastures, but may also decrease their quality. Increases in atmospheric CO2 can increase the productivity of plants on which livestock feed. However, the quality of some of the forage found in pasturelands decreases with higher CO2. As a result, cattle would need to eat more to get the same nutritional benefits.

Impacts on Fisheries

American fishermen catch or harvest five million metric tons of fish and shellfish each year. U.S. fisheries contribute more than $1.55 billion to the economy annually (as of 2012). Many fisheries already face multiple stresses, including overfishing and water pollution. Climate change may worsen these stresses. In particular, temperature changes could lead to significant impacts.

The ranges of many fish and shellfish species may change. In waters off the northeastern United States, several economically important species have shifted northward since the late 1960s. The three species shown in [the figure to the left] (American lobster, red hake, and black sea bass) have moved northward by an average of 119 miles.

Many aquatic species can find colder areas of streams and lakes or move north along the coast or in the ocean. Nevertheless, moving into new areas may put these species into competition with other species over food and other resources, as explained on the Ecosystems Impacts page.

Some marine disease outbreaks have been linked with changing climate. Higher water temperatures and higher estuarine salinities have enabled an oyster parasite to spread farther north along the Atlantic coast. Winter warming in the Arctic is contributing to salmon diseases in the Bering Sea and a resulting reduction in the Yukon Chinook Salmon, Finally, warmer temperatures have caused disease outbreaks in coral, eelgrass, and abalone.

Changes in temperature and seasons can affect the timing of reproduction and migration. Many steps within an aquatic animal's lifecycle are controlled by temperature and the changing of the seasons. For example, in the Northwest warmer water temperatures may affect the lifecycle of salmon and increase the likelihood of disease. Combined with other climate impacts, these effects are projected to lead to large declines in salmon populations.

In addition to warming, the world's oceans are gradually becoming more acidic due to increases in atmospheric carbon dioxide (CO 2). Increasing acidity could harm shellfish by weakening their shells, which are created by removing calcium from seawater. Acidification also threatens the structures of sensitive ecosystems upon which some fish and shellfish rely.

International Impacts

Climate change is very likely to affect food security at the global, regional, and local level. Climate change can disrupt food availability, reduce access to food, and affect food quality. For example, projected increases in temperatures, changes in precipitation patterns, changes in extreme weather events, and reductions in water availability may all result in reduced agricultural productivity. Increases in the frequency and severity extreme weather events can also interrupt food delivery, and resulting spikes in food prices after extreme events are expected to be more frequent in the future. Increasing temperatures can contribute to spoilage and contamination.

Internationally, these effects of climate change on agriculture and food supply are likely to be similar to those seen in the United States. However, other stressors such as population growth may magnify the effects of climate change on food security. In developing countries, adaptation options like changes in crop-management or ranching practices, or improvements to irrigation are more limited than in the United States and other industrialized nations.

Any climate-related disturbance to food distribution and transport, internationally or domestically, may have significant impacts not only on safety and quality but also on food access. For example, the food transportation system in the United States frequently moves large volumes of grain by water. In the case of an extreme weather event affecting a waterway, there are few, if any, alternate pathways for transport. High temperatures and a shortage of rain in the summer of 2012 led to one of the most severe summer droughts the nation has seen and posed serious impacts to the Mississippi River watershed, a major transcontinental shipping route for Midwestern agriculture. This drought resulted in significant food and economic losses due to reductions in barge traffic, the volume of goods carried, and the number of Americans employed by the tugboat industry. The 2012 drought was immediately followed by flooding throughout the Mississippi in the spring of 2013, which also resulted in disruptions of barge traffic and food transport. Transportation changes such as these reduce the ability of farmers to export their grains to international markets, and can affect global food prices.

Impacts to the global food supply concern the United States because food shortages can cause humanitarian crises and national security concerns. They also can increase domestic food prices.

References
[6] CCSP (2008). The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in the United States. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Backlund, P., A. Janetos, D. Schimel, J. Hatfield, K. Boote, P. Fay, L. Hahn, C. Izaurralde, B.A. Kimball, T. Mader, J. Morgan, D. Ort, W. Polley, A. Thomson, D. Wolfe, M. Ryan, S. Archer, R. Birdsey, C. Dahm, L. Heath, J. Hicke, D. Hollinger, T. Huxman, G. Okin, R. Oren, J. Randerson, W. Schlesinger, D. Lettenmaier, D. Major, L. Poff, S. Running, L. Hansen, D. Inouye, B.P. Kelly, L Meyerson, B. Peterson, and R. Shaw. U.S. Environmental Protection Agency, Washington, DC, USA. [8] USDA (2012). 2012 Census of Agriculture: Volume 1, Chapter 1: U.S. National Level Data, Table 33. U.S. Department of Agriculture.

# data[].attributes.attachment_link.title
Climate Impacts on Agriculture and Food Supply

# data[].attributes.attachment_link.description
Agriculture is an important sector of the U.S. economy. The crops, livestock, and seafood produced in the United States contribute more than $300 billion to the economy each year. When food-service and other agriculture-related industries are included, the agricultural and food sectors contribute more than $750 billion to the gross domestic product.

# data[].attributes.body
What are the potential impacts of increased CO 2 on agriculture?

# data[].attributes.attachment_link.title
NASA Study: Rising Carbon Dioxide Levels Will Help and Hurt Crops - NASA

# data[].attributes.attachment_link.description
Elevated carbon dioxide concentrations in the atmosphere may increase water-use efficiency in crops and considerably mitigate yield losses due to climate

# data[].attributes.body
How will climate change affect agricultural pests and diseases?

# data[].attributes.attachment_link.readable_text
Diseases like the potato blight have ruined harvests in the past - and still haunt farmers today. Research suggests climate change will spread those pests and pathogens

AydAn Mutlu

When we talk about the challenge of ending hunger and feeding a growing global population, most of the focus is put on increasing production. That's not surprising - "more" is our solution to most social problems. But some of the hunger gap could be closed by making better use of the crops we do produce now. Take plant pests and diseases, which have historically laid waste to whole harvests. The Irish potato famine of the 1840s - caused by the oomycete Phytophthora infestans - led to the deaths of a million people and the emigration of another 2 million Irish. The 1943 Great Bengal Famine in India led to the deaths of some 3 million and was caused by a simple fungus. Even today, when farmers are better equipped to control pests and pathogens, between 10% and 16% of crop production each year is lost to biological threats. That's enough food to feed hundreds of millions of people.

Pests and pathogens are weather-dependent, and many thrive in hotter, wetter climates - which is exactly the sort of change that global warming is predicted to create over the coming decades. In a new meta-analysis published in the journal Nature Climate Change, researchers from the University of Exeter and the University of Oxford looked at how plant pests and diseases will respond to a warming world, and found that their range has been steadily shifting toward both poles, as climate change warms higher latitudes. They found that crop pests have been spreading north and south a little less than 2 miles (3.2 km) a year since 1960, though there's a lot of variety within individual species.

( MORE: As Northeast Asia Bakes, Climate Scientists Predict More Extreme Heat Waves on the Horizon)

We can already see the results of some of that pest expansion. Warmer winters have allowed the mountain pine beetle to take hold over a greater swath of the Pacific Northwest, allowing it to spread further and higher, at altitudes that in the past would have been too cold for the insect. As a result, the mountain pine beetle is now at epidemic levels throughout the American West. The rice blast fungus, present in scores of countries, has migrated to wheat, and has become a scourge of farmers in Brazil.

Dan Bebber, an author of the paper at the University of Exeter, said in a statement:

If crop pests continue to march polewards as the earth warms, the combined effects of a growing world population and the increased loss of crops to pests will pose a serious threat to global food security.

The truly scary possibility is that a new or re-emerging plant disease could decimate one of the few crops - rice, wheat, corn - that the global diet is based on. We've already had a few close calls. Wheat rust, which is caused by a fungus, devastated wheat crops in Africa, and is poised to spread to other major wheat-producing countries. It doesn't help that over the years farmers have narrowed the genetic diversity of commodity crops, which limits our ability to respond if a new pest or disease takes hold. That's why we need to support seed banks, which store a variety of strains within a crop, to ensure that farmers have weapons to respond to a new plant plague. They'll need those bullets in a warmer world.

MORE: The Trouble With Beekeeping in the Anthropocene

# data[].attributes.attachment_link.title
A Warmer World Will Mean More Pests and Pathogens for Crops

# data[].attributes.attachment_link.description
Diseases like the potato blight have ruined harvests in the past - and still haunt farmers today. Research suggests climate change will spread those pests and pathogens When we talk about the challenge of ending hunger and feeding a growing global population, most of the focus is put on increasing production.

# data[].attributes.body
How do temperature increases and severe weather impact crops?

# data[].attributes.attachment_link.readable_text
On This Page:

Overview

Agriculture is an important sector of the U.S. economy. The crops, livestock, and seafood produced in the United States contribute more than $300 billion to the economy each year. When food-service and other agriculture-related industries are included, the agricultural and food sectors contribute more than $750 billion to the gross domestic product.

Agriculture and fisheries are highly dependent on the climate. Increases in temperature and carbon dioxide (CO2) can increase some crop yields in some places. But to realize these benefits, nutrient levels, soil moisture, water availability, and other conditions must also be met. Changes in the frequency and severity of droughts and floods could pose challenges for farmers and ranchers and threaten food safety. Meanwhile, warmer water temperatures are likely to cause the habitat ranges of many fish and shellfish species to shift, which could disrupt ecosystems. Overall, climate change could make it more difficult to grow crops, raise animals, and catch fish in the same ways and same places as we have done in the past. The effects of climate change also need to be considered along with other evolving factors that affect agricultural production, such as changes in farming practices and technology.

Impacts on Crops

Crops grown in the United States are critical for the food supply here and around the world. U.S. farms supply nearly 25% of all grains (such as wheat, corn, and rice) on the global market.[4] Changes in temperature, atmospheric carbon dioxide (CO 2), and the frequency and intensity of extreme weather could have significant impacts on crop yields.

For any particular crop, the effect of increased temperature will depend on the crop's optimal temperature for growth and reproduction. In some areas, warming may benefit the types of crops that are typically planted there, or allow farmers to shift to crops that are currently grown in warmer areas. Conversely, if the higher temperature exceeds a crop's optimum temperature, yields will decline.

Higher CO2 levels can affect crop yields. Some laboratory experiments suggest that elevated CO2 levels can increase plant growth. However, other factors, such as changing temperatures, ozone, and water and nutrient constraints, may counteract these potential increases in yield. For example, if temperature exceeds a crop's optimal level, if sufficient water and nutrients are not available, yield increases may be reduced or reversed. Elevated CO2 has been associated with reduced protein and nitrogen content in alfalfa and soybean plants, resulting in a loss of quality. Reduced grain and forage quality can reduce the ability of pasture and rangeland to support grazing livestock.

More extreme temperature and precipitation can prevent crops from growing. Extreme events, especially floods and droughts, can harm crops and reduce yields. For example, in 2010 and 2012, high nighttime temperatures affected corn yields across the U.S. Corn Belt, and premature budding due to a warm winter caused $220 million in losses of Michigan cherries in 2012.

Dealing with drought could become a challenge in areas where rising summer temperatures cause soils to become drier. Although increased irrigation might be possible in some places, in other places water supplies may also be reduced, leaving less water available for irrigation when more is needed.

Many weeds, pests, and fungi thrive under warmer temperatures, wetter climates, and increased CO2 levels. Currently, U.S. farmers spend more than $11 billion per year to fight weeds, which compete with crops for light, water, and nutrients. The ranges and distribution of weeds and pests are likely to increase with climate change. This could cause new problems for farmers' crops previously unexposed to these species.

Though rising CO2 can stimulate plant growth, it also reduces the nutritional value of most food crops. Rising levels of atmospheric carbon dioxide reduce the concentrations of protein and essential minerals in most plant species, including wheat, soybeans, and rice. This direct effect of rising CO2 on the nutritional value of crops represents a potential threat to human health. Human health is also threatened by increased pesticide use due to increased pest pressures and reductions in the efficacy of pesticides.

Impacts on Livestock

Americans consume more than 36 million metric tons of meat and poultry annually. Livestock and poultry account for over half of U.S. agricultural cash receipts, often over $100 billion per year. Changes in climate could affect animals both directly and indirectly.

Heat waves, which are projected to increase under climate change, could directly threaten livestock. In 2011, exposure to high temperature events caused over $1 billion in heat-related losses to agricultural producers. Heat stress affects animals both directly and indirectly. Over time, heat stress can increase vulnerability to disease, reduce fertility, and reduce milk production.

Drought may threaten pasture and feed supplies. Drought reduces the amount of quality forage available to grazing livestock. Some areas could experience longer, more intense droughts, resulting from higher summer temperatures and reduced precipitation. For animals that rely on grain, changes in crop production due to drought could also become a problem.

Climate change may increase the prevalence of parasites and diseases that affect livestock. The earlier onset of spring and warmer winters could allow some parasites and pathogens to survive more easily. In areas with increased rainfall, moisture-reliant pathogens could thrive.

Potential changes in veterinary practices, including an increase in the use of parasiticides and other animal health treatments, are likely to be adopted to maintain livestock health in response to climate-induced changes in pests, parasites, and microbes. This could increase the risk of pesticides entering the food chain or lead to evolution of pesticide resistance, with subsequent implications for the safety, distribution, and consumption of livestock and aquaculture products.

Increases in carbon dioxide (CO2) may increase the productivity of pastures, but may also decrease their quality. Increases in atmospheric CO2 can increase the productivity of plants on which livestock feed. However, the quality of some of the forage found in pasturelands decreases with higher CO2. As a result, cattle would need to eat more to get the same nutritional benefits.

Impacts on Fisheries

American fishermen catch or harvest five million metric tons of fish and shellfish each year. U.S. fisheries contribute more than $1.55 billion to the economy annually (as of 2012). Many fisheries already face multiple stresses, including overfishing and water pollution. Climate change may worsen these stresses. In particular, temperature changes could lead to significant impacts.

The ranges of many fish and shellfish species may change. In waters off the northeastern United States, several economically important species have shifted northward since the late 1960s. The three species shown in [the figure to the left] (American lobster, red hake, and black sea bass) have moved northward by an average of 119 miles.

Many aquatic species can find colder areas of streams and lakes or move north along the coast or in the ocean. Nevertheless, moving into new areas may put these species into competition with other species over food and other resources, as explained on the Ecosystems Impacts page.

Some marine disease outbreaks have been linked with changing climate. Higher water temperatures and higher estuarine salinities have enabled an oyster parasite to spread farther north along the Atlantic coast. Winter warming in the Arctic is contributing to salmon diseases in the Bering Sea and a resulting reduction in the Yukon Chinook Salmon, Finally, warmer temperatures have caused disease outbreaks in coral, eelgrass, and abalone.

Changes in temperature and seasons can affect the timing of reproduction and migration. Many steps within an aquatic animal's lifecycle are controlled by temperature and the changing of the seasons. For example, in the Northwest warmer water temperatures may affect the lifecycle of salmon and increase the likelihood of disease. Combined with other climate impacts, these effects are projected to lead to large declines in salmon populations.

In addition to warming, the world's oceans are gradually becoming more acidic due to increases in atmospheric carbon dioxide (CO 2). Increasing acidity could harm shellfish by weakening their shells, which are created by removing calcium from seawater. Acidification also threatens the structures of sensitive ecosystems upon which some fish and shellfish rely.

International Impacts

Climate change is very likely to affect food security at the global, regional, and local level. Climate change can disrupt food availability, reduce access to food, and affect food quality. For example, projected increases in temperatures, changes in precipitation patterns, changes in extreme weather events, and reductions in water availability may all result in reduced agricultural productivity. Increases in the frequency and severity extreme weather events can also interrupt food delivery, and resulting spikes in food prices after extreme events are expected to be more frequent in the future. Increasing temperatures can contribute to spoilage and contamination.

Internationally, these effects of climate change on agriculture and food supply are likely to be similar to those seen in the United States. However, other stressors such as population growth may magnify the effects of climate change on food security. In developing countries, adaptation options like changes in crop-management or ranching practices, or improvements to irrigation are more limited than in the United States and other industrialized nations.

Any climate-related disturbance to food distribution and transport, internationally or domestically, may have significant impacts not only on safety and quality but also on food access. For example, the food transportation system in the United States frequently moves large volumes of grain by water. In the case of an extreme weather event affecting a waterway, there are few, if any, alternate pathways for transport. High temperatures and a shortage of rain in the summer of 2012 led to one of the most severe summer droughts the nation has seen and posed serious impacts to the Mississippi River watershed, a major transcontinental shipping route for Midwestern agriculture. This drought resulted in significant food and economic losses due to reductions in barge traffic, the volume of goods carried, and the number of Americans employed by the tugboat industry. The 2012 drought was immediately followed by flooding throughout the Mississippi in the spring of 2013, which also resulted in disruptions of barge traffic and food transport. Transportation changes such as these reduce the ability of farmers to export their grains to international markets, and can affect global food prices.

Impacts to the global food supply concern the United States because food shortages can cause humanitarian crises and national security concerns. They also can increase domestic food prices.

References
[6] CCSP (2008). The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in the United States. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Backlund, P., A. Janetos, D. Schimel, J. Hatfield, K. Boote, P. Fay, L. Hahn, C. Izaurralde, B.A. Kimball, T. Mader, J. Morgan, D. Ort, W. Polley, A. Thomson, D. Wolfe, M. Ryan, S. Archer, R. Birdsey, C. Dahm, L. Heath, J. Hicke, D. Hollinger, T. Huxman, G. Okin, R. Oren, J. Randerson, W. Schlesinger, D. Lettenmaier, D. Major, L. Poff, S. Running, L. Hansen, D. Inouye, B.P. Kelly, L Meyerson, B. Peterson, and R. Shaw. U.S. Environmental Protection Agency, Washington, DC, USA. [8] USDA (2012). 2012 Census of Agriculture: Volume 1, Chapter 1: U.S. National Level Data, Table 33. U.S. Department of Agriculture.

# data[].attributes.attachment_link.title
Climate Impacts on Agriculture and Food Supply

# data[].attributes.attachment_link.description
Agriculture is an important sector of the U.S. economy. The crops, livestock, and seafood produced in the United States contribute more than $300 billion to the economy each year. When food-service and other agriculture-related industries are included, the agricultural and food sectors contribute more than $750 billion to the gross domestic product.

# data[].attributes.headline
What are 3 ways in which vegetation influences weather patterns?

# data[].attributes.subject
What are 3 ways in which vegetation influences weather patterns?

# data[].attributes.attachment_link.readable_text
Vegetation covers a considerable portion of the earth and has an effect on weather and climate. Vegetation influences both albedo of the earth and the amount of water vapor and carbon dioxide in the air.
Why do I care? Humans are altering the vegetation on earth, and it is impacting weather and climate. Farmers and other community professionals might find it interesting to learn about the role of vegetation in weather and climate.

I should already be familiar with: Evapotranspiration and Evaporation, Earth's Energy Balance, Albedo, The Water Cycle

Vegetation includes all plants from evergreen forests to grassy meadows and cropland. All types of plants play a role in both the water cycle and the earth's energy balance. They affect weather and climate mostly through evapotranspiration and albedo.
Effects on Weather and Climate
With vegetation covering about 20% of our planet, it's no surprise that plants affect climate. However, it is surprising how much plants affect weather. Plants process and release water vapor (necessary for cloud formation) and absorb and emit energy used to drive weather. Plants also produce their own micro-weather by controlling the humidity and temperature immediately surrounding their leaves through transpiration. Most plants and forest soils have a very low albedo, (about .03 to .20) and absorb a large amount of energy. However, plants don't contribute to overall warming because the excess warmth is offset by evaporative cooling from transpiration.

Figure A. Land use over US.

Since climate is basically an average of the weather over a long period of time, vegetation is important to climate. In fact, the process of photosynthesis is responsible for building up atmospheric oxygen to the level we enjoy today (21% concentration). Plants also help keep our climate stable over time by offsetting temperature and moisture fluctuations through transpiration. Plants also use carbon dioxide during photosynthesis, which slightly offsets the amount of greenhouse gas being released in the atmosphere through the burning of fossil fuels. Vegetation is necessary for normal weather and climate.

Land Use

There are nearly 2 billion acres of land in the continental United States. Land use classifies the types of vegetation on the land. In the past thirty years, there has been an increase in developed land and a decrease in cultivated crop land. An increase in developed land means more areas are covered by buildings, concrete and asphalt.

It is interesting to note that historical land use changes have also affected the climate of the Southeast. In Georgia, for example, around 1900 there were large areas of bare ground associated with cotton fields and other crops. By the late 1900s, most of Georgia (over 70 percent) had reverted to pine and deciduous forests once cotton was no longer farmed due to the boll weevil (beetle which feeds on cotton buds and flowers) and soil degradation. Some climatologists think that the slight cooling of the Southeast over the 1900s may have been due in part to the higher evapotranspiration and cooler conditions associated with forests compared to bare ground in cropland.

Figure B. Land use in the Southeast.

The more recent increase in developed land, especially around urban areas, causes a "heat island" effect, and large cities with no exposed ground or vegetation become very hot during the day. The lack of vegetation means there is no transpiration to cool the air. Also, asphalt has a very low albedo and absorbs a lot of sunlight, which adds to the excessive heat. The concrete and asphalt release their heat slowly at night, too, leading to warmer conditions overnight as well as during the day. Uncultivated crop land also stays warmer due to the lack of transpiration, but doesn't get as hot as developed areas. Figure A displays different types of land use for the entire United States in 2003. In the past ten years there was a major slowdown in the amount of land being developed.

Figure B shows the distribution of land use in the Southeast (AL, FL, GA, NC, SC and VA). On average, the Southeast has twice as much developed land as the rest of the United States, although this is offset by the fact that over half of the land in the Southeast is forest. Forests are beneficial because they use copious amounts of carbon dioxide, as well as mitigating heat through transpiration.

How does this relate to agriculture?

Farmers are responsible for maintaining a majority of the cropland vegetation in arable regions of the world. Vegetation (or the lack of it) is a key factor affecting weather patterns and micro-climates. The following factors are affected by vegetation:

Figure C. Bradford pear orchard. (Image from Bridget Lassiter).

(1) Plant covers and crops are inherently responsible for a vast majority of the water storage and usage. When irrigation is taken out of the equation, rain, snow, fog, dew, frost and soil water are all used and captured by vegetation. Some of this water is intercepted by the leaves themselves, and some of the water that infiltrates the soil is absorbed by plant roots. When water is available in excess, plants can transpire large volumes of water as a by-product of photosynthesis. This in turn causes evaporative cooling in the atmosphere directly surrounding the crop.

(2) Vegetation contributes to the level of carbon dioxide that is present in the atmosphere. Seasonal variations have shown that higher levels of CO 2 are measured in the early-mid part of the growing season. There are also daily variations in CO 2, with the highest levels measured during the day.

(3) Radiation measurements within a crop or vegetated area reveal a complex relationship between absorption, reflection, transmission and emission. The albedo of a crop is lower than the sum of all of the leaves in the canopy due to differences in crop architecture and angle of solar radiation. Most individual leaves have an albedo of about 0.25, but the albedo for a crop is less and depends upon crop height. For a crop of 1m in height, the surface albedo is between 0.18 and 0.25. However, this value is dependent upon the vegetation type. If leaves are wilted, or if the soil is exposed beneath the canopy this value can be different. Also, this albedo measurement is the one taken at mid-day. Early morning and late day measurements of albedo are much higher and the values follow the position of the sun in the sky. Also, tropical measurements of albedo are usually less that for a similar vegetated surface found at higher latitudes.

Want to learn more?
Effects of Climate Change on the Southeast
Links to National Science Education Standards:

Earth Science: EEn.2.2.1 : Explain the consequences of human activities on the lithosphere (such as mining, deforestation, agriculture, overgrazing, urbanization, and land use) past and present.

# data[].attributes.attachment_link.title
Vegetation: Its Role in Weather and Climate

# data[].attributes.attachment_link.description
Vegetation covers a considerable portion of the earth and has an effect on weather and climate. Vegetation influences both albedo of the earth and the amount of water vapor and carbon dioxide in the air. Why do I care? Humans are altering the vegetation on earth, and it is impacting weather and climate.

# data[].attributes.headline
Include a map that indicates hurricane impacts on the US

# data[].attributes.subject
Include a map that indicates hurricane impacts on the US

# data[].attributes.body
What is still uncertain about the connection between hurricanes and global warming?

# data[].attributes.attachment_link.title
Hurricanes: Science and Society: Long-term Records of Hurricane Activity

# data[].attributes.body
Use the graph to answer the following - WHAT is changing?

# data[].attributes.body
1. Make 3 observations about the cost of severe weather.
2. What is another reason storms are getting more expensive besides larger hurricanes?

# data[].attributes.attachment_link.readable_text
Extreme weather, made worse by climate change, along with the health impacts of burning fossil fuels, has cost the U.S. economy at least $240 billion a year over the past ten years, a new report has found.

And yet this does not include this past month's three major hurricanes or 76 wildfires in nine Western states. Those economic losses alone are estimated to top $300 billion, the report notes. Putting it in perspective, $300 billion is enough money to provide free tuition for the 13.5 million U.S. students enrolled in public colleges and universities for four years.

In the coming decade, economic losses from extreme weather combined with the health costs of air pollution spiral upward to at least $360 billion annually, potentially crippling U.S. economic growth, according to this new report, The Economic Case for Climate Action in the United States, published online Thursday by the Universal Ecological Fund.

"Burning fossil fuels comes at a giant price tag which the U.S. economy cannot afford and not sustain," said Sir Robert Watson, coauthor and director at the U.K's Tyndall Center for Climate Change Research.

"We want to paint a picture for Americans to illustrate the fact that the costs of not acting on climate change are very significant," Watson, the former chair of the Intergovernmental Panel on Climate Change, told National Geographic.

Watson is quick to point out that extreme weather events, including heat waves, hurricanes, wildfires, and droughts, are not caused by climate change. However, there is no question their intensity and frequency in many cases has been made worse by the fact the entire planet is now 1.8 degrees F (1 degree C) hotter, he said in an interview.

While a 1.8 degree F (1 degree C) increase may seem small, it's having a major economic impact on the U.S. According to data provided by the National Oceanic and Atmospheric Administration (NOAA), the number of extreme weather events causing at least $1 billion in economic losses has increased more than 400 percent since the 1980s. Some of that increase is due to increased amounts of housing and commercial infrastructure along coastlines. "However that doesn't account for big increases in the last decade," Watson said.

And much more global warming is coming-3.6 degrees F (2 degrees C) temperature by 2050 and even greater warming beyond that-unless bigger cuts in fossil-fuel emissions are made than those promised in the 2015 Paris Climate Agreement, said Watson. "The impacts of climate change are certainly going to get more than twice as bad," he said. ( Learn more about why this hurricane season has been so catastrophic.)

The report also looks at low-carbon solutions that can cut emissions and air pollution and benefit the U.S. economy. For instance, doubling the current share of renewable energy could create 500,000 new jobs while substantially cutting the amount of electricity currently generated using coal-improving air quality and reducing health costs.

Renewable energy, even when subsidized, will save America billions of dollars, according to the first national study of the future costs and benefits of renewable portfolio standards (RPS). Twenty-nine states have RPS-regulations requiring increased production of energy from renewable energy sources.

If existing RPS programs continue unchanged from now until 2050 they'd generate about 40 percent of U.S. electricity and save $97 billion in air pollution health costs and $161 billion in climate damage reductions, the Assessing the Costs and Benefits of U.S. Renewable Portfolio Standards study found. But if all states meet their Clean Power Plan obligations solely with renewables they'd generate 35 percent of U.S. electricity by 2030 and 49 percent by 2050.

The health benefit savings and climate impact cost reductions in this scenario would be over $1.1 trillion. However, the Trump Administration signed an Executive Order calling for a review of the Clean Power Plan last March and the new head of the EPA has told states they no longer have to comply.

RPS policies do increase electric system costs and may increase rates in some states but the overall costs are far less than the health benefits and cost reductions, said lead author Ryan Wiser, a senior scientist at Lawrence Berkeley National Laboratory.

"RPS programs provide a big social benefit to all Americans," Wiser said in an interview. However, RPS policies are not the most efficient way to reduce fossil fuel use, he added.

"Pretty well every economist will tell you that a carbon tax or cap and trade are better."

In the 1980s acid rain air pollution was curbed through a cap and trad e program championed by George H.W. Bush. It was the first such program in the world and worked quite well, said Wiser.

Additional Benefits to Tackling Emissions

Switching to renewables will also save enormous amounts of freshwater. Electricity generation is the nation's biggest water user because coal and gas boil large amounts of water to make electricity. If 35 percent of this generation was renewable it would reduce water use enough to meet the needs of 1.9 million homes, according to Wiser's study. However, the cost benefits of this water savings is not included in the report, nor are other environmental costs and health benefits.

The Economic Case for Climate Action report also doesn't include a number of climate-related losses such as reduced crop yields from drought. Those amounted to $56 billion since 2012. Nor does it include economic losses from health impacts of heat waves or impacts on ecosystems and water resources.

"Our report is an under estimate of the real costs of continued use of fossil fuels," Watson said.

"Anything we estimate now is an underestimate," said Amir Jina of the University of Chicago and co-author of yet another new study looking at impacts of climate change on the U.S. "Climate change is not isolated to small increases in global temperature, but to local impacts to our health and well-being that could be enormous."

South and Midwest to Be Hardest Hit

Estimating Economic Damage from Climate Change in the United States is a state-of-the-art analysis that projects future costs and benefits county by county based on current and past data. It found counties in states in the South and lower Midwest would be the hardest hit economically without strong action to curb climate change.

"The Gulf Coast will take a massive hit. Its exposure to sea-level rise-made worse by potentially stronger hurricanes-poses a major risk to its communities. Increasingly extreme heat will drive up violent crime, slow down workers, amp up air conditioning costs," said co-author Robert Kopp, director of the Institute of Earth, Ocean, and Atmospheric Sciences at Rutgers University.

Programs like federal flood insurance insulate coastal communities from some of these risks but it means citizens a long way from the coast bear the financial costs. The same applies to disaster relief.

Billions of local, state and federal taxpayer dollars will rightly go towards the recovery efforts from the devastating impacts of Hurricanes Harvey, Irma, and Maria. However, those monies could have gone elsewhere to grow our economy and that affects every American, said Jina. "What would we have done with this rebuilding money if we didn't have to use it to rebuild?"

The study shows that these big storms lower the long-run growth of the U.S. economy and that their economic and human impacts ripple through the country for up to two decades. New Orleans hasn't fully recovered from Hurricane Katrina in 2005. Many small businesses never bounced back. Ten years after the storm the unemployment rate was still higher than pre-Katrina levels. Research shows that after most hurricanes more people tend to rely heavily on unemployment insurance and Medicaid, increasing the strain on those publicly funded programs, Jina said.

"The 'hidden costs' of carbon dioxide emissions are no longer hidden, since now we can see them clearly in the data," he said.

# data[].attributes.attachment_link.title
Hidden Costs of Climate Change Running Hundreds of Billions a Year

# data[].attributes.attachment_link.description
Extreme weather, made worse by climate change, along with the health impacts of burning fossil fuels, has cost the U.S. economy at least $240 billion a year over the past ten years, a new report has found. And yet this does not include this past month's three major hurricanes or 76 wildfires in nine Western states.

# data[].attributes.body
How will global warming impact fish? Explain.

# data[].attributes.attachment_link.readable_text
Warming temperatures and loss of oxygen in the sea will shrink hundreds of fish species-from tunas and groupers to salmon, thresher sharks, haddock and cod-even more than previously thought, a new study concludes.

Because warmer seas speed up their metabolisms, fish, squid and other water-breathing creatures will need to draw more oxyen from the ocean. At the same time, warming seas are already reducing the availability of oxygen in many parts of the sea.

A pair of University of British Columbia scientists argue that since the bodies of fish grow faster than their gills, these animals eventually will reach a point where they can't get enough oxygen to sustain normal growth.

"What we found was that the body size of fish decreases by 20 to 30 perent for every 1 degree Celsius increase in water temperature," says author William Cheung, director of science for the university's Nippon Foundation-Nereus Program.

These changes, the scientists say, will have a profound impact on many marine food webs, upending predator-prey relationships in ways that are hard to predict. ( Read about how climate change is resulting in smaller mountain goats.)

"Lab experiments have shown that it's always the large species that will become stressed first," says lead author Daniel Pauly, a professor at the university's Institute for the Ocean and Fisheries, and principal investigator for the Sea Around Us. "Small species have an advantage, respiration-wise."

Still, while many scientists applaud the discovery, not all agree that Pauly's and Cheung's work supports their dramatic findings. The study was published today in the journal Global Change Biology.

Pauly is perhaps best known for his global, sometimes controversial, studies of overfishing. But since his dissertation in the 1970s, he has researched and promoted a principle that suggests fish size is limited by the growth capacity of gills. Based on this theory, he, Cheung and other authors published research in 2013 that showed average body weight for some 600 species of ocean fish could shrink 14-24 percent by 2050 under climate change.

"It's a difficult concept for people to imagine because we breathe air," Pauly says. "Our problem is getting enough food-not oxygen. But for fish, it's very different. For humans, it would be like trying to breathe through a straw."

Other scientists have linked oxygen to smaller fish sizes. In the North Sea, for example, haddock, whiting, herring and sole have already seen significant loss in size in areas of the sea with less oxygen.

Still, Pauly's and Cheung's 2013 results were criticized in some corners as overly simplistic. Earlier this year, a group of European physiologists argued that Pauly's basic premise about gill size was, itself, flawed.

So Pauly and Cheung used more sophisticated models and re-examined their theory.

The new paper doubles down on their earlier case, explains the gill theory in more detail and argues that it can and should be used as a guiding principle. The new work goes on to suggests their original conclusions actually underestimated the scale of the problem fish will soon face.

The earlier paper, for example, suggested the size of some species, such as tuna, may be less affected by climate change. But the new research states that fast-swimming ever-mobile tunas, which already consume significant oxygen, may be more susceptible than some other fish.

In fact, in parts of the tropical Atlantic, Cheung says, there is a vast region where oxygen is already low in the open ocean. Other studies have shown tunas altering their range to avoid that bad water.

"Tunas' distributions have followed very closely the bounds of these oxygen minimum zones," Cheung says.

Some fish experts find Pauly's and Cheung's gill theory and new work convincing.

Jeppe Kolding, a biology professor at the University of Bergen in Norway, who studies fish in Africa, says Pauly's gill concept is the only thing he's found that elucidates the dwarfing he's seen in Nile tilapia, guppies, and a type of sardine found in Zambia and in Lake Victoria. "It does explain the phenomena I have encountered in Africa," he says.

Nick Dulvy, a marine biologist at Simon Fraser University, says his own research "tends to confirm" Pauly's ideas. "It is absoutely an inevitability that as fish grow heavier they will eventually reach a point where oxygen intake does not match their metabolic demand."

Hans-Otto Poertner, marine animal physiologist at Germany's Bremen University and Alfred Wegener Institute for Polar and Marine Research, says Pauly's work doesn't account for how well some species may acclimate or adapt to changing ocean conditions. But, he says, the authors "convincingly argue" that oxygen will affect fishes' sensitivity to temperature and curb body size.

Still, one of Pauly's earlier critics, Sjannie Lefevre, a physiologist with the University of Oslo in Norway, lead author of the critique published earlier this year in the same journal, continues to find Pauly's gill theory wanting.

"I am not at all impressed or convinced by their attempt to refute our arguments," Lefevre says, adding that she doesn't "consider the new results any more reliable."

She says fish absolutely are capable of growing larger gills. "There are no geometric constraints stopping gills from growing as fast as the body of a fish," she says.

She and Poertner could not view the work more differently. Lefevre says she hopes ecologists and modelers keep "an open and cautious mind" before accepting such unifying theories.

Poertner, on the other hand, maintains that Pauly's and Cheung's work is a great example of the right way to apply such theories.

The new research shows how "careful use of an overarching principle in a wide set of observations across species can support insight that is difficult to reach otherwise," he says.

Update: The quote from Nick Dulvy has been updated to specify "metabolic demand" instead of "metabolic rate" in order to be more accurate.

# data[].attributes.attachment_link.title
Climate Change May Shrink the World's Fish

# data[].attributes.attachment_link.description
Warming temperatures and loss of oxygen in the sea will shrink hundreds of fish species-from tunas and groupers to salmon, thresher sharks, haddock and cod-even more than previously thought, a new study concludes. Because warmer seas speed up their metabolisms, fish, squid and other water-breathing creatures will need to draw more oxyen from the ocean.

# data[].attributes.headline
How is population growth impacting the fishing demand

# data[].attributes.subject
How is population growth impacting the fishing demand

# data[].attributes.body
What are 3 things that are changing in our oceans due to climate change?

# data[].attributes.attachment_link.title
Climate Change Indicators: Oceans | US EPA

# data[].attributes.body
What is happening to the coral reefs?

# data[].attributes.attachment_link.authors[].name
US Department of Commerce, National Oceanic and Atmospheric Administration

# data[].attributes.attachment_link.title
How does climate change affect coral reefs?

# data[].attributes.attachment_link.description
Natural disasters such as hurricanes, tropical storms, tsunamis, and landslides have the potential to be the source of a tremendous amount of marine debris. High winds, heavy rain, storm surge, and flooding associated with these disasters can pull large structures, household products, and outdoor items into surrounding waters.

# data[].attributes.body
Use the images to answer the following - How is the pH changing?

# data[].attributes.body
1. What are two diseases we are worried about buried in the permafrost?
2. Why are they still "alive"?

# data[].attributes.attachment_link.title
As Earth Warms, the Diseases That May Lie within Permafrost Become a Bigger Worry

# data[].attributes.attachment_link.description
Scientists are witnessing the theoretical turning into reality: infectious microbes emerging from a deep freeze

# data[].attributes.headline
Describe the relationship between climate change, the movement of people, and disease transmission.

# data[].attributes.subject
Describe the relationship between climate change, the movement of people, and disease transmission.

# data[].attributes.attachment_link.title
Opinion | Another deadly consequence of climate change: The spread of dangerous diseases

# data[].attributes.attachment_link.description
The Ebola epidemic was just the beginning.

# data[].attributes.body
How is climate change contributing to the spread of Lyme disease?

# data[].attributes.attachment_link.readable_text
Most creepy, crawly bugs are pretty much harmless when it comes to infectious diseases.
What Is #CuriousGoat?
But there are two classes of little critters that cause big - and we're talking big - problems: ticks and mosquitoes.

To learn how climate change could alter the course of tick- and mosquito-borne diseases, we talked to two scientists who have devoted a major chunk of their careers to answering that question.

Let's start with the bloodsuckers that can stay on your skin for days.

Ticks

Cocktail party chatter: These little guys aren't insects. They're arachnids. That's the same class of animal as spiders.

What they cause: Ticks are best known for transmitting Lyme disease. But these arachnids carry more than a dozen diseases in the U.S., including spotted fevers, a malaria-like disease and several rare but deadly viruses, such as Heartland virus and Powassan.
How climate change will affect the spread of these diseases:
Lyme disease is rapidly expanding in the U.S. In the past 30 years, the number of cases has more than tripled. The disease - and the ticks that transmit it - have spread northward all the way to Maine in New England and Minnesota in the Midwest.

Part of the reason? A warming climate, says Rick Ostfeld, an ecologist at the Cary Institute of Ecosystem Studies in Millbrook, N.Y. "We know that climate change has contributed to Lyme disease spreading northward and to higher elevations."

Here's why.

Ticks need to feed on the blood of three animals over the course of two years to complete their life cycle, Ostfeld says. That meal could be a mouse, a chipmunk, a human - just something with nice, warm blood.

Ticks can look for this yummy meal only when the weather is warmer - the cold-blooded insects can't move when temperatures drop near freezing.

" If they don't have a long enough season to find a host, they'll use up their reserves and drop dead," Ostfeld says.

A few decades ago, many places in the U.S. just didn't have a long enough summer to keep the ticks healthy. And tick-borne diseases weren't a problem in Northern states.

But with spring coming earlier in many places, ticks end up having more time to look for their food. So they're surviving in more places.

States in the Northern U.S., such as Maine and Vermont, used to be inhospitable to ticks. Now they have huge outbreaks of Lyme disease each summer.

And these earlier springs mean ticks are out on the prowl earlier. Ticks typically become a big problem in mid-May. But Ostfeld and his colleagues have found that warmer springs have bumped up the peak feeding time a few weeks, to early May or even late April.

Bottom line: Climate change is likely to make Lyme disease more common in the U.S. The ticks are creeping northward and starting to bite people earlier in the year.

Now, there is one big caveat to this: Ticks don't like dry weather, Ostfeld says. So if climate change brings drier springs, we might actually see a decline in tick activity in some places.

Mosquitoes

Cocktail party chatter: Known as Mozzies in Australia and New Zealand, mosquitoes don't actually "bite" people. Instead, they " saw" into our skin with a set of six needles.

What they transmit: The list of mosquito-borne diseases is long, including chikungunya, dengue, malaria, West Nile virus, yellow fever and Zika.

How climate change is likely to affect the spread of these diseases: It's no secret that mosquitoes like warm weather. Just like ticks, these critters become inactive at low temperatures and stop growing because they're coldblooded. And winters that drop below freezing can actually wipe out particular mosquito species, including the one that spreads dengue, yellow fever and Zika.

But warmer weather doesn't necessarily mean a greater chance of mosquitoes spreading more dengue, more yellow fever and more Zika, says Erin Mordecai, who studies the ecology of infectious diseases at Stanford University.

In fact, hotter weather could mean fewer cases of mosquito-borne diseases in some places.

Here's why.

When a mosquito bites a person with a virus or parasite, the insect swallows the pathogen. Eventually, the mosquito can pass that pathogen onto another person. But not right away.

"That pathogen has to basically go through an incubation period within the mosquito - anywhere from a couple of days to over a week," Mordecai says.

The amount of time depends on the temperature outside. The warmer the weather, the faster the pathogen will be ready to infect another person.

But there's a major obstacle for the pathogen: Mosquitoes don't live very long, only about a few weeks to a month.

The mosquito's life span also depends on the outside temperature - but in the opposite direction. The warmer the weather, the shorter the mosquito's life.

So in a way, it's a race between maturation of the pathogen and the mosquito's life span.

At cooler temperatures, the pathogen will take too long to mature. The mosquito will be dead before it has a chance to infect another person. At high temperatures, the pathogen will mature quickly but the mosquito will also die quickly.

But in places where the temperature is currently just slightly too cool for transmission of mosquito-borne diseases, warmer summers could tip the balance and trigger transmission of mosquito-borne diseases in new places.

"That's why we're worried about climate change in temperate zones," Mordecai says. "Warmer temperatures will speed up the parasite's development rate and just make the region more suitable for transmission of diseases."

So in the Southern U.S., for example, the transmission season might expand from just summer into spring and fall. "Or in a place like Miami, that already has warm temperatures, transmission could occur year-round," she says.

Bottom line: The jury is still out on how climate change will alter mosquito-borne diseases. The final outcome is likely to depend on the place, the diseases and the specific mosquito that carries them. But here in the U.S., warmer springs and summers are likely to make transmission worse in the South and possibly cause diseases to creep northward.

Thanks to our readers who submitted questions to #CuriousGoat. Want to propose a question for our next callout, on the topic of world hunger and famine? Click .

# data[].attributes.attachment_link.title
#CuriousGoat: Will Climate Change Help Ticks And Mosquitoes Spread Disease?

# data[].attributes.attachment_link.description
Most creepy, crawly bugs are pretty much harmless when it comes to infectious diseases. What Is #CuriousGoat? But there are two classes of little critters that cause big - and we're talking big - problems: ticks and mosquitoes.

# data[].attributes.body
How is malaria spread and why could it increase in a warmer world?

# data[].attributes.attachment_link.readable_text
Introduction: Looking Ahead

Predicting the climate of the future, its impacts on us, and what we can do about it.

Credit: Sarah Craig, Flickr

Isle de Jean Charles, Louisiana, is one of the first places in the United States where sea level rise is (at least partly) causing people to relocate. This island had already been shrinking because of erosion and a lack of new sediment due to diversions upriver.

The Future of Climate Change

Climate change is already happening. It's changing the oceans, weather, ice, and living systems in countless ways. What will the planet be like in 50 or 100 years? To answer these questions, scientists have developed climate models-computer programs that simulate Earth's climate and the systems that affect it. Climate models tell us which of many possible future outcomes is most likely.

The biggest question mark in climate models is the human factor. How will we change our behavior? How much will we change our use of fossil fuels, and the resulting emissions of heat-trapping carbon dioxide?

A Computer Model of the Whole Planet

If we can't precisely predict the weather three weeks from now, how can we predict the climate decades in the future? The answer is that climate models don't need to be as precise about timing and location. A weather forecast asks, for example: Will it rain in downtown Oakland on November 10? A climate model asks: How much it will rain in Northern California over the next ten winters? Climate models can make longer-term predictions because they're much less specific about timing.

A climate model subdivides the Earth's atmosphere around it into thousands of boxes in a 3-D grid. For each box, such as this one of air over the ocean, the model starts with the current conditions-the temperature, humidity, wind, and so on. Then it calculates all of the ongoing processes-increasing sunlight, rising air pressure, etc. Each of these is represented with a very complex equation. The model calculates the conditions in each box over time, and how it's influenced by all the neighboring boxes. Source: California Institute of Technology

Big Climate Math

With so many changing ocean and atmospheric factors, climate models are extremely complex. A supercomputer running a climate model needs to make trillions of calculations just to simulate a single day of the climate. Yet climate models are surprisingly good at predicting how the climate will change over the course of 10, 20, or 50 years. They can also answer questions, such as what will happen if we emit more or less CO 2 into the atmosphere.

Climate models require immense computing power, such as that of the Summit supercomputer at the Department of Energy's Oak Ridge National Laboratory. It can perform up to 200,000 trillion calculations per second. Source: Oak Ridge National Laboratory

More Links About Looking Ahead

Educational Global Climate Modeling: Run a global climate model on your computer. This site walks you through how to download and try a research-grade global climate model that with a user-friendly interface.

Intergovernmental Panel on Climate Change (IPCC): Comprehensive assessments of scientific, technical, and socioeconomic dimensions of climate change; established by the World Meteorological Organization and the UN Environment Programme

Climate Time Machine: This series of visualizations shows how Earth's key climate indicators are changing over time.

Dataset How Much Warmer?

Dataset 1
How Much Warmer?

One of the clearest predictions from climate change modeling is warmer temperatures. Almost everywhere in the world will be warmer by 2100, and we'll see more extreme heat. The amount of warming we'll get depends mainly on the amount of fossil fuels we burn.

The black line on this graph shows the average of a set of temperature simulations for the 20th century. The colored lines show projected temperatures for the 21st century based on three emissions scenarios. Shaded areas around each colored line indicate the range of likely outcomes based on running the climate model many times. See the full interactive graph at climate.gov. Source: NOAA's Climate.gov

Choosing Our Future

In predicting the climate of the future, the biggest unknown is what humans will do. How will we change our use of fossil fuels-and thus our CO 2 emissions? The answer involves individual and collective decisions at local, national, and international levels.

To understand the consequences of the paths we might take, scientists use climate models. They input different amounts of future CO 2 emissions to see how they affect the climate.

RCP stands for representative concentration pathway, meaning a pathway that assumes a certain concentration of carbon dioxide in the atmosphere. The number in each scenario name indicates how much heat would be added to the atmosphere. Source: Based on data from the 2013 IPCC report

How Would That Feel in Sacramento?

Here's what high emissions, the RCP 8.5 scenario, would mean for Sacramento, California's state capitol. The average high temperature for the whole year, including winter, would be ten degrees warmer, rising from about 74ºF (in the 1960s through 1980s) to about 83ºF by 2100.

Not only that, there would be about 10 times as many extreme heat days (heat in the 89th percentile)-about 40 days per year in 2100, compared with only four days in the 1980s. There would also be about six heat waves per year, instead of one, and these heat waves would last longer. (A heat wave here means four days in a row of 104ºF or higher.)

Observed temperatures are shown until 2005, followed by data from four climate models for 2006 through 2099. The gray band shows the possible variability in the modeled future. Source: Based on graph from Cal Adapt, the California Energy Commission

Dataset Rain and Snow

Climate change models predict that some parts of the world will get more rain and snow than the historical average, while others will get less. Different climate models give slightly different projections, yet there's one thing nearly all the models predict: intense rainstorms will get even more intense, wreaking havoc through flooding and erosion.

How much will rain and snow increase or decrease in the future? This animation shows climate model predictions of rain and snow for different parts of the world, from 2006 through 2100. Blue colors mean more rain or snow than average (based on 1971-2000), tan to orange mean less. Source: NASA's Goddard Space Flight Center Scientific Visualization Studio

Wetter in India, Drier in the Mediterranean

A few regions are predicted to get more rain or snow. In the United States, the Northeast will likely get wetter, as will Alaska. The Pacific Ocean near the equator will be much wetter, as will India and areas near the North and South Poles, such as Canada, Russia, and northern China.

The Mediterranean Sea region will get much drier-including Spain, Portugal, Italy, Greece, Turkey, and North Africa's coast. Southern Africa-South Africa, Namibia, and Botswana-will be much drier, as will southwestern Australia.

The outlook is not so clear for the rest of the globe-different climate models give different results.

When It Pours, It Will Really Pour!

One thing all the climate models agree on: big rainstorms will be get even bigger, dumping lots more rain. In the United States, this is most likely in the Northeast and the upper Midwest. This could increase the chances of river flooding, especially along the coast where sea level is also rising. Weather records show that extreme rains are already beginning to increase.

Predictions of how much more often extreme rainfall or snowfall events will happen at the end of this century (2081 to 2100) under the high carbon dioxide emissions scenario (RCP 8.5). The darkest color in the continental United States means these events would happen five times as often as they did at the end of the 20th century. Source: Based on NOAA National Climate Data Center image

Flooding of the Souris River in Minot, North Dakota, inundated more than 4,000 homes in June 2011. Source: U.S. Air Force

California's Future: Snow Turns to Rain

Climate models don't always give a clear picture of the future, and precipitation in California is a good example. Some models say the state will get more, some say less, and others say it will stay the same.

What's more certain: snowpacks in the Sierra Nevada mountains will all but disappear, as warming temperatures cause precipitation to more often fall as rain instead of snow.

That's bad news for California's water supply. The state relies on mountain snowbanks that melt throughout the summer, yielding steady flows of water to fill the reservoirs. Without snow, managing water will be much trickier.

California's snowpack will shrink by two-thirds by 2050, according to the climate models, as more precipitation falls as rain instead of snow. This animation shows 10-year averages of the April snowpack from the 1950s through the 2090s, according to a high CO 2 emissions scenario. Source: Cal Adapt, California Energy Commission

Dataset Sea Level Rise

Dataset 3
Sea Level Rise

Climate change is already causing sea levels to rise. And climate models predict this will continue, and may even accelerate in the future if carbon emissions increase. Sea level rise will threaten low-lying islands, towns, and cities around the world with catastrophic flooding. Those in the most vulnerable spots are already planning to relocate. In large metropolitan areas, like the Bay Area, governments are planning ways to cope with the threats to infrastructure, such as highways, railways, and sewage treatment plants.

In this map of future sea level rise in the Bay Area, blue areas are projected to be flooded-that is, below sea level-by the year 2100, assuming a high carbon dioxide emissions scenario, and assuming we don't build or raise any barriers. Green areas would also be below sea level, but are currently protected by ridges, levees, or other barriers. Click the image to zoom in or explore how other places will be affected. Source: Climate Central

How Does Climate Change Cause Sea Level Rise?

It's a combination of two factors:

1. Rising temperatures melt glaciers and ice caps, sending more and more water into the ocean.

2. Warmer ocean water takes up more space. Just like the liquid in a thermometer, water expands as it gets warmer. Each drop of ocean water expands just a bit, but when you combine all the drops in the ocean, it's enough to raise sea levels.

Austria's Pasterze Glacier is retreating about 33 feet (10 meters) a year, and has lost half its volume since 1851. Source: H. Raab

How High Will It Get?

If we continue on our current path-getting most of our energy from burning fossil fuels-sea levels are projected to rise an additional 0.7 meters (2.5 feet) on average by 2100, though it could rise by as much as 1 meter (3 feet). That's according to climate model predictions from the IPCC in 2014-some later studies suggest that we should double those numbers.

The longer we delay the transition toward renewable energy sources, the more likely this outcome will be. If we switch to renewables sooner, sea levels could rise less.

Sea level has been rising since the mid-1800s, when people started burning fossil fuels, such as coal. It began rising faster around the 1990s. The pink line shows future rise projected for the high emissions scenario-our current path; the pink area is the range of uncertainty. The blue line and light blue area represent a very low emissions scenario. Sea level rise at 2100 is different from what's listed in the text above because this graph is compared to the early 19th century instead of the late 20th century. Source: Based on 2013 IPCC graph

Frequent Flooding to Come

A few feet of sea level rise might sound manageable, especially if you don't live right along the shoreline. But the levees, sea walls, and other barriers that protect coastal cities are only designed for ordinary high tides and storm waves. With sea level rise, catastrophic flooding that used to happen once in a decade or once in a century could be a regular occurrence.

Who's at Risk?

More than 100 million people worldwide may be exposed to inundation by 2100, according to climate research. The most vulnerable communities often don't have the financial resources to cope with this flooding.

Some South Pacific island nations, such as Kiribati, are already giving up the battle against sea level rise. Kiribati President Anote Tong said in 2008 that the country had reached "the point of no return." He added, "the emissions in the atmosphere will carry on contributing to climate change, to produce a sea level change so in time our small, low-lying islands will be submerged."

On Tarawa Island in Kiribati, a wall temporarily protects a small house from the sea. In 2014, the Kiribati government purchased land in Fiji, and is actively urging citizens to abandon their low-lying island nation.

Urban Infrastructure

It's not only coastal homes that are threatened. Highways, railways, airports, and sewage treatment plants are often built directly along shorelines, especially in the Bay Area. And they're protected by relatively low, poorly maintained levees.

On this map of Hayward, at the east end of the San Mateo Bridge, blue shows land that would be flooded by four feet of water level rise. Threatened areas include Highway 92 leading to the Bridge, as well as a sewage treatment plant at the shore just north of the area shown. Source: Bay Conservation and Development Comission (BCDC)

More Sites About Sea Level Rise

Dataset Extreme Weather

Dataset 4
Extreme Weather

If carbon emissions continue to grow quickly, the weather is predicted to change dramatically, with most weather events becoming more extreme. Stronger hurricanes, longer droughts, more and wetter thunderstorms, and more catastrophic flooding are all among the results from climate models.

Soil moisture levels from 1950 through 2095, based on climate model results for a high carbon dioxide emissions scenario (RCP 8.5). Brown means less moisture than average, blue means more. The Southwest is projected to get much longer and more severe droughts than at any time in recent memory. Source: NASA's Scientific Visualization Studio

Heat Makes Drought Worse

We think of drought as a lack of rainfall. But the warmer temperatures projected by climate models could cause drought simply by drying out the soil through evaporation.

The map above shows how much dryer the soil is expected to be. Mexico and the "four corners" states-Utah, Colorado, Arizona, and New Mexico-are projected to get both less water and higher temperatures-the perfect recipe for epic drought.

Different Catastrophes for Different Areas

Just as the weather's a bit different wherever you go, the projections of extreme weather vary all around the world. For example, the Southwest can expect more intense and frequent droughts, Florida can expect more catastrophic flooding, and over the Atlantic Ocean, hurricanes are expected to be more intense, bringing much more rain.

Climate models predict that by the year 2080, the risk of flooding will increase in the pink areas, and decrease in the green areas. In the darkest pink areas, such as Southeast Asia, a catastrophic flood that used to happen once in 100 years will happen every 15 years. Source: Based on IPCC image

Warmer Waters Feed the Hurricane Machine

The hurricanes that batter the eastern United States and Caribbean begin far away, in the tropics of the Atlantic Ocean. As climate change warms the oceans, more water will evaporate into the atmosphere, adding power to newborn tropical storms.

More than 20,000 homes were flooded in Port Arthur, Texas, by Hurricane Harvey. In total, the storm caused more than $125 billion in damage, mostly in the Houston area, tying it with Katrina for the costliest tropical storm in history. Source: U.S. Army National Guard

Heat-Related Deaths

As extreme heat events increase, it's very likely that we'll see more heat related illness and deaths from conditions like heat exhaustion, and aggravated heart or lung illnesses, especially among the elderly and the very young

More Links About Extreme Weather:

Dataset Solutions and Adaptations

Dataset 5
Solutions and Adaptations

Climate change is a complex, global problem, so figuring out what to do about it can seem confusing.

The most important factor in any effort to fight climate change: reducing the burning of fossil fuels, which emits carbon dioxide. Read on for examples of initiatives that are already starting to do just that.

And since climate change is already in progress, we can't stop it altogether. So communities around the world are planning ways to adapt to changes like sea level rise, warmer temperatures, and more extreme weather.

Members of the 2017 Walk and Bike Youth Leaders Program visited California's state capital to learn how to advocate for state policies that promote safer streets and better public transportation in their communities. This initiative of the California Bicycle Coalition aims to improve infrastructure so that more Californians can bike or walk instead of driving. Source: California Bicycle Coalition

Where Do We Burn the Most Fossil Fuels?

To reduce fossil fuel use, it's helpful to know where we burn them. Fossil fuels-coal, natural gas, and petroleum-based fuels like gasoline-are incredibly rich sources of energy, so we've come to rely on them to power almost everything we do. Here's which sectors burn the most fossil fuels.

Homes and offices use the most fossil fuels, mainly via electricity-the fuel itself is burned at a power plant. Tied for second are transportation-cars, planes, trains, trucks, ships, and buses-and industries, such as factories and processing plants. Source: U.S. EPA

Buying Cleaner Electricity

Many people wish they could get their electricity from renewable energy sources, such as wind, solar, or hydroelectric power. But for now, most local utility companies don't sell it.

In a growing number of cities and counties, citizens are working together to create Community Choice Aggregation, where the city or county buys power directly from renewable sources, and has it transmitted to homes and businesses by the utility company. In 2018, Community Choice was legal in seven states: California, Ohio, Illinois, New Jersey, New York, Massachusetts, and Rhode Island, but others were exploring it.

At a 2018 community meeting in Rye, New York, two advocates from Sustainable Westchester describe how the town could join the county's community choice aggregation program, which was already bringing renewable energy to 110,000 residents at prices only slightly higher than fossil fuel power. Source: Rye Sustainability Committee

Electrifying Transit Systems

The grassroots organization Southern Oregon Climate Action Now works towards regional solutions for climate change. Its transportation group promoted a test of zero-emission electric buses. The goal is for local transit authorities to shift from diesel buses to all-electric. Because such transitions are expensive, they require active public support.

A zero-emissions electric bus prepares to leave for its test-run from Medford, Oregon, to the town of Grants Pass. Southern Oregon Climate Action Now members rode the bus to build support for the future transition to electric buses. Source: Southern Oregon Climate Action Now

Envisioning a Resilient Future

As sea levels rise, shoreline communities will be forced to adapt to new realities. The Resilient by Design Bay Area Challenge brings together community members with governments, funders, designers, and others, to design innovative solutions to sea level rise. With extensive community input, designers developed solutions that would work for the residents of the affected neighborhoods.

A vision of San Francisco Bay shoreline in the future, by ouR-HOME design team, which would turn investments in sea level rise adaptations into economic opportunities, building health, wealth, and home ownership for residents of North Richmond. It blends green infrastructure with affordable housing planning. Source: Resilient by Design | Bay Area Challenge

The Exploratorium's Fisher Bay Observatory Gallery 6 hosted several public presentations and discussions from the Resilient by Design | Bay Area Challenge. Source: Exploratorium

Making a Plan

Some states and cities already have climate action plans-concrete guidelines and tasks to reduce their use of fossil fuels and adapt to future climate change. The Center for Climate and Energy Solutions has a list of states that already have such a plan in place.

More About Solutions and Adaptation

# data[].attributes.attachment_link.description
Predicting the climate of the future, its impacts on us, and what we can do about it. Climate change is already happening. It's changing the oceans, weather, ice, and living systems in countless ways. What will the planet be like in 50 or 100 years?

# data[].attributes.body
Describe the relationship between climate change and waterborne diseases.

# data[].attributes.attachment_link.provider_name
National Institute of Environmental Health Sciences

# data[].attributes.attachment_link.title
Page not found | National Institute of Environmental Health Sciences

# data[].attributes.body
1. How do forests help regulate climate?
2. How do forest fires impact the atmosphere?

# data[].attributes.attachment_link.readable_text
A monster forest fire that began in early May is still burning in Canada's vast, isolated north woods. That may seem of little consequence to anyone other than the 88,000 residents of Fort McMurray forced to flee as the blaze swept into the northern Alberta city.

Yet large fires like these matter immensely to the rest of the planet.

Fires so intense that they consume millions of acres of trees and scorch the soil on the forest floor have become the kind of extreme disruptors that are remaking the boreal forest and transforming its role as one of the world's great protectors against global warming.

The boreal, which takes its name from Boreas, the Greek god of the North Wind, encircles the top of the globe in North America and Eurasia. Half lies in Siberia, another third in Canada, and the rest in Alaska and Scandinavia.

It is Earth's single largest land habitat, and it stores about 30 percent of the carbon found on the planet's surfaces-more than any other terrestrial ecosystem. The forest also provides refuge for animals and birds as they relocate from southern habitats that have become too warm.

Climate change is playing out twice as fast in the boreal forest than it is on the rest of the planet. Permafrost is thawing, and vegetation is changing as climatic zones migrate north faster than trees can adapt.

Already, dramatic change can be glimpsed from space: The tundra is turning green, while the boreal forest is turning brown.

Some scientists predict the boreal forest may reach a disastrous-and irreversible- tipping point this century and shift from carbon storehouse into a major source of greenhouse gas emissions. Others contend that the tipping point has already been reached.

"These forests matter to the rest of us on Earth because of how they help regulate climate by keeping carbon in the soil and in the trees and out of the atmosphere," says Peter Griffith, founding director of NASA's Carbon Cycle and Ecosystems Office.

"So where fires are getting bigger and happening more often, that impacts the rest of us. It's putting more greenhouse gases into the atmosphere that would have stayed locked up for perhaps hundreds of years."

Griffith is director of the Arctic Boreal Vulnerability Experiment (ABoVE), a decade-long NASA study that is using satellite imagery to examine the impact of climate change on the Arctic tundra and boreal forests.

The region under NASA's microscope spans 2.5 million square miles (6.4 million square kilometers). The project launched its first field research earlier this spring on nearly two dozen separate studies, which range from the changing migratory patterns of caribou and birds to the role of fire as a contributor to climate change.

Scott Goetz, deputy director and scientist at Woods Hole Research Center in Falmouth, Massachusetts, first documented the shifting colors of the tundra and boreal forest in 2005. The change happens as more vegetation grows in the warming Arctic, and forests struggle to survive against fire and insect infestations in warmer and drier conditions.

For the NASA study, Goetz will continue to examine this change. The boreal is expanding in the north, he says, and declining in the southern region. Evergreen stands of conifers are being replaced by deciduous trees, larch, and birch or, in some places, by less productive grassland.

"That was a surprise, to see declining productivity," Goetz says of the struggle in the southern end of the forest. "Most think they would be greater and more productive, but warmer and drier is not conducive to productivity."

Another natural focus of the NASA study is thawing permafrost, which, when melted, would release a mother lode of stored carbon and methane into the atmosphere. That would create more warming, which would in turn create more thawing. It becomes a vicious cycle, known as positive feedback.

"Once you start thawing the permafrost out, you can't stop it. It's completely irreversible," says Kevin Schaefer, a scientist at the University of Colorado's National Snow and Ice Data Center. "Once organic matter thaws out, even if the permafrost refroze, you can't put it back. It's a climatic tipping point."

Now, as forest fires become more intense and frequent, they are creating a similar cycle. Large fires are not only killing all the trees, they are burning through the peat, the rich organic soil on the forest floor that serves as a large reservoir for carbon.

"The warmer the Earth gets, the more fire we get, and the more fire we get, the more greenhouse gases we get," says Mike Flannigan, director of the Western Partnership for Wildland Fire Science at the University of Alberta in Edmonton.

Conditions are ripe for more frequent fires in multiple ways. For every degree of global warming, the forest needs a 15 percent increase in precipitation to compensate for the increased drying caused by warming, according to a recent study. Instead, forests are getting less rain, not more.

Scientists also have found that every degree of warming sets off a 12 percent increase in lightning activity, Flannigan says. In the woods, lightning means more forest fires.

Fires in Canada's huge, largely unpopulated forest often burn for months, and are extinguished by the first snow of autumn. Last summer, fires in the Northwest Territories burned more than 3.4 million acres (1.375 million hectares)-an area the size of Maryland.

So far, the Fort McMurray fire has burned more than 1.45 million acres (589,600 hectares) and is considered "held," meaning it has stopped gaining in size but is still burning out of control. That could change if the weather turns hot and windy.

Investigators believe the first blaze was caused by humans, although it's unclear whether that was deliberate or accidental. At times, it burned with such intensity that it spawned its own thunderstorms, complete with lightning that ignited new fires within the fire.

"I have seen lightning before," says Flannigan. "But spawning new fires? That is a new one for me."

TheFort McMurray fire turned out to be exactly the large, intense fire that scientists in the NASA study want to examine, although it didn't quite work out that way. Brendan Rogers, an Earth scientist at the Woods Hole Research Center, is studying how deeply large fires burn the layers of peat on the forest floor.

"There have been a lot of studies about how climate affects fires," he says. "We want to study how fire feedback affects climate."

Earlier last spring, Rogers and a team of five scientists chose the forest zone around Fort McMurray for a smoke-measuring experiment, because the area rates high for fire severity. Smoke would help determine the age of the carbon being released, which could then be compared to soil samples.

"If you look at the smoke from these fires, you can look at the average of the carbon in that smoke, and since most comes from the soil, you can get an average of the burn depth," he says.

Fire season begins earlier these days, but the team did not expect a blaze to break out in early May.

The team's smoke sensors arrived in Fort McMurray the same day the city evacuated, and Rogers has not learned their fate. Some of the volunteers recruited to monitor the sensors lost their homes and are now preoccupied with rebuilding their lives.

"It would have been perfect, so it is ironic and also a bit scary," he says. "You need to be close, but not too close. We didn't expect one to happen right there in town."

# data[].attributes.attachment_link.title
Forest Fires Can Heat Up the Whole Planet

# data[].attributes.attachment_link.description
A monster forest fire that began in early May is still burning in Canada's vast, isolated north woods. That may seem of little consequence to anyone other than the 88,000 residents of Fort McMurray forced to flee as the blaze swept into the northern Alberta city.

# data[].attributes.body
What do the colors of the map indicate? Is there a correlation between forest fire risk and geographical location - explain.

# data[].attributes.attachment_link.readable_text
States were evaluated for how ready they will be to manage and mitigate wildfires in coming decades.
Above: Wildfire preparedness, according to StatesAtRisk.org
Two organizations have collaborated to develop what they call America's Preparedness Report Card (StatesAtRisk.org), laying out their scores for how America's 50 states are preparing for a changing climate. They came up with ratings in five categories:

According to their web site, ClimateCentral.org, one of the two organizations, is "An independent organization of leading scientists and journalists researching and reporting the facts about our changing climate and its impact on the public." The other, ICF International, is a private company that appears to offer a very broad range of consulting services.

We were most interested in their analysis of wildfire issues. The states colored gray on the map above are labeled "n/a", which means wildfire was not identified as a threat. The methodology used was to determine the average number of days each year when the Keetch-Byram Drought Index exceeded 600. This was weighted by the county-level population living in the wildland-urban interface (WUI). They did not take into account fire history, the number of homes destroyed by fire, or vegetation.

We noticed, for example, that wildfire was not identified as a threat in Colorado in spite of the fact that in 2012, the Waldo Canyon Fire burned more than 18,000 acres, destroyed 347 homes in Colorado Springs and killed two people. Almost exactly a year later, the Black Forest Fire ignited east of the city and burned more than 15,000 acres, 486 homes and killed two people.

Their map is different from the ones below created by the U.S. Forest Service (showing the frequency of wildfires greater than 299 acres from 1994 to 2013) and FEMA's map of wildfire hazard potential.

In looking at two other states, Alabama was given an "F" in wildfire preparedness while California earned an "A".

The list of factors that were considered in determining the grades included:

Current wildfire vulnerability assessments and hazard mitigation and emergency response plans;

Guidelines or requirements for resilient activities (e.g., construction);

Wildfire adaptation policy or guidelines;

Communication with residents about mitigating for wildfire.

Below are graphical wildfire preparedness summaries from StatesAtRisk.org for Alabama and California:

# data[].attributes.attachment_link.title
Wildfire preparedness for a changing climate - Wildfire Today

# data[].attributes.attachment_link.description
States were evaluated for how ready they will be to manage and mitigate wildfires in coming decades. Above: Wildfire preparedness, according to StatesAtRisk.org Two organizations have collaborated to develop what they call America's Preparedness Report Card (StatesAtRisk.org), laying out their scores for how America's 50 states are preparing for a changing climate.

# data[].attributes.body
Why are fires increasing?

# data[].attributes.attachment_link.readable_text
This summer, wildfires swept across some 22 regions of Russia, blanketing the country with dense smoke and in some cases destroying entire villages. In the foothills of Boulder, Colo., this month, wildfires exacted a similar toll on a smaller scale.

That's just the tip of the iceberg. Thousands of wildfires large and small are underway at any given time across the globe. Beyond the obvious immediate health effects, this "biomass" burning is part of the equation for global warming. In northern latitudes, wildfires actually are a symptom of the Earth's warming.

'We already see the initial signs of climate change, and fires are part of it," said Dr. Amber Soja, a biomass burning expert at the National Institute of Aerospace (NIA) in Hampton, Va.

And research suggests that a hotter Earth resulting from global warming will lead to more frequent and larger fires.

The fires release "particulates" -- tiny particles that become airborne -- and greenhouse gases that warm the planet.

A common perception is that most wildfires are caused by acts of nature, such as lightning. The inverse is true, said Dr. Joel Levine, a biomass burning expert at NASA Langley Research Center in Hampton, Va.

"What we found is that 90 percent of biomass burning is human instigated," said Levine, who was the principal investigator for a NASA biomass burning program that ran from 1985 to 1999.

Levine and others in the Langley-led Biomass Burning Program travelled to wildfires in Canada, California, Russia, South African, Mexico and the wetlands of NASA's Kennedy Space Center in Florida.

Biomass burning accounts for the annual production of some 30 percent of atmospheric carbon dioxide, a leading cause of global warming, Levine said.

Dr. Paul F. Crutzen, a pioneer of biomass burning, was the first to document the gases produced by wildfires in addition to carbon dioxide.

"Modern global estimates agree rather well with the initial values," said Crutzen, who shared the Nobel Prize in Chemistry 1995 with Mario J. Molina and F. Sherwood Rowland for their "work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone."

Whether biomass burning is on the rise globally is not clear. But it definitely is increasing in far northern latitudes, in "boreal" forests comprised largely of coniferous trees and peatlands.

The reason is that, unlike the tropics, northern latitudes are warming, and experiencing less precipitation, making them more susceptible to fire. Coniferous trees shed needles, which are stored in deep organic layers over time, providing abundant fuel for fires, said Soja, whose work at the NIA supports NASA.

"That's one of the reasons northern latitudes are so important," she said, "and the smoldering peat causes horrible air quality that can affect human health and result in death."

Fires in different ecosystems burn at different temperatures due to the nature and structure of the biomass and its moisture content. Burning biomass varies from very thin, dry grasses in savannahs to the very dense and massive, moister trees of the boreal, temperate and tropical forests.

Fire combustion products vary over a range depending on the degree of combustion, said Levine, who authored a chapter on biomass burning for a book titled "Methane and Climate Change," published in August by Earthscan.

Flaming combustion like the kind in thin, small, dry grasses in savannahs results in near-complete combustion and produces mostly carbon dioxide. Smoldering combustion in moist, larger fuels like those in forest and peatlands results in incomplete combustion and dirtier emission products such as carbon monoxide.

Boreal fires burn the hottest and contribute more pollutants per unit area burned.

Being near large wildfires is a unique experience, said Levine. "The smoke is so thick it looks like twilight. It blocks out the sun. It looks like another planet. It's a very eerie experience."

In Russia, the wildfires are believed caused by a warming climate that made the current summer the hottest on record. The hotter weather increases the incidence of lightning, the major cause of naturally occurring biomass burning.

Soja said she hopes the wildfires in Russia prompt the country to support efforts to mitigate climate change. In fact, Russia's president, Dmitri A. Medvedev, last month acknowledged the need to do something about it.

"What's happening with the planet's climate right now needs to be a wake-up call to all of us, meaning all heads of state, all heads of social organizations, in order to take a more energetic approach to countering the global changes to the climate," said Medvedev, in contrast to Russia's long-standing position that human-induced climate change is not occurring.

Michael Finneran
NASA Langley Research Center

# data[].attributes.attachment_link.title
NASA - Wildfires: A Symptom of Climate Change

# data[].attributes.attachment_link.description
Thousands of wildfires are underway at any given time across the globe, and this “biomass” burning is part of the equation for global warming.

# data[].attributes.body
Examine Figures 1-3.
Identify two trends that have changed in wildfire numbers in the US.

# data[].attributes.attachment_link.readable_text
Figure 1. Wildfire Frequency in the United States, 1983-2021

Figure 2. Wildfire Extent in the United States, 1983-2021

Figure 3. Damage Caused by Wildfires in the United States, 1984-2020

Figure 6. Comparison of Monthly Burned Area Due to Wildfires in the United States Between 1984-2001 and 2002-2020

Figure 7. Comparison of Monthly Burned Area Due to Wildfires in the Eastern and Western United States Between 1984-2001 and 2002-2020

Key Points

Since 1983, the National Interagency Fire Center has documented an average of approximately 70,000 wildfires per year (see Figure 1). Compiled data from the Forest Service suggest that the actual total may be even higher for the first few years of nationwide data collection that can be compared. The data do not show an obvious trend during this time.

The extent of area burned by wildfires each year appears to have increased since the 1980s. According to National Interagency Fire Center data, of the 10 years with the largest acreage burned, all have occurred since 2004, including the peak year in 2015 (see Figure 2). This period coincides with many of the warmest years on record nationwide (see the U.S. and Global Temperature indicator). The largest increases have occurred during the spring and summer months (see Figure 6).

The late 1990s were a period of transition in certain climate cycles that tend to shift every few decades.18 This shift-combined with other ongoing changes in temperature, drought, and snowmelt-may have contributed to warmer, drier conditions that have fueled wildfires in parts of the western United States.19,20

Of the total area burned each year from 1984 to 2020, the proportion of burned land suffering severe damage has ranged from 5 to 23 percent (see "high" category in Figure 3).

Land area burned by wildfires varies by state. Fires burn more land in the western United States than in the East, and parts of the West and Southwest show the largest increase in burned acreage between the first half of the period of record in Figures 4 and 5 (1984-2001) and the second half (2002-2020). Burned acreage in the West has increased noticeably in nearly every month of the year (see Figure 7).

The peak of the U.S. wildfire season is occurring earlier (see Figure 6). In 1984-2001, burned area peaked in August. More recently, it has peaked in July. An average of 1.7 million acres burned in July of each year from 2002 to 2020.

Background

Together, forests, shrubland, and grassland cover more than half of the land area in the United States.1 These ecosystems are important resources, both environmentally and economically. Although wildfires occur naturally and play a long-term role in the health of these ecosystems, changing wildfire patterns threaten to upset the status quo. Multiple studies have found that climate change has already led to an increase in wildfire season length, wildfire frequency, and burned area.2, 3 The wildfire season has lengthened in many areas due to factors including warmer springs, longer summer dry seasons, and drier soils and vegetation.4 Similarly, climate change threatens to increase the frequency, extent, and severity of fires through increased temperatures and drought (see the U.S. and Global Temperature and Drought indicators).5 Earlier spring melting and reduced snowpack (see the Snowpack indicator) result in decreased water availability during hot summer conditions, which in turn contributes to an increased wildfire risk, allowing fires to start more easily and burn hotter. These trends of longer wildfire seasons and larger wildfire size are predicted to continue as more frequent and longer droughts occur.6 In addition to climate change, other factors-land use, large-scale insect infestation, fuel availability (including invasive species such as highly flammable cheatgrass), and management practices, including fire suppression-play an important role in wildfire frequency and intensity. All of these factors influencing wildfires vary greatly by region and over time, as do precipitation, wind, temperature, vegetation types, and landscape conditions. Therefore, understanding changes in fire characteristics requires long-term records, a regional perspective, and consideration of many factors.7

Wildfires have the potential to harm property, livelihoods, and human health. Fire-related threats are increasing, especially as more people live in and around forests, grasslands, and other natural areas.8 According to the National Oceanic and Atmospheric Administration, between 1980 and 2021 the United States had 20 wildfire events that caused more than $1 billion in damage; 16 of those have occurred since 2000.9 Over the past few decades, the United States has routinely spent more than $1 billion per year to fight wildfires, including $2.3 billion in 2020.10 These efforts have resulted in the deaths of more than 1,000 firefighters since 1910.11 Even in communities far downwind, wildfire smoke has been directly linked to poor air quality that can lead to significant health effects and costs to society (emergency department visits, hospital admissions, and deaths, often due to respiratory ailments).12, 13, 14, 15, 16

Beyond the human and societal impacts, wildfires also affect the Earth's climate. Forests in particular store large amounts of carbon. When they burn, they immediately release carbon dioxide into the atmosphere, which in turn contributes to climate change. After burning, forests also release carbon dioxide more gradually through decomposition.

About the Indicator

This indicator defines a wildfire as "a wildland fire originating from an unplanned ignition, such as lightning, volcanos, unauthorized and accidental human caused fires, and prescribed fires that are declared wildfires."17 This indicator tracks four aspects of wildfires over time: the total number of fires (frequency), the total land area burned (extent), the degree of damage that fires cause to the landscape (severity), and the acreage burned by fires starting in each month of the year (seasonal patterns).

The total area and total number of fires are tracked by the National Interagency Fire Center, which compiles reports from local, state, and federal agencies that are involved in fighting wildfires. The U.S. Forest Service tracked similar data using a different reporting system until 1997. Those data have been added to this indicator for comparison. Burn severity, state-level acreage, and monthly totals are based on data from the Monitoring Trends in Burn Severity (MTBS) project, which provides the location, ignition date, size, and other statistics for every individual wildfire that meets certain size criteria (≥ 1,000 acres in the western United States or ≥ 500 acres in the eastern United States). MTBS compares the "greenness" of satellite images taken before and after a fire to classify how severely the land has been burned. Burn severity provides an indication of the ecological damage and how long the effects of wildfires are likely to last.

Although some nationwide fire data have been collected since the early 1900s, this indicator starts in 1983 (Figures 1 and 2) and 1984 (Figures 3 through 7), when nationwide data collection became more complete and standardized. EPA divided the time period in Figures 5, 6, and 7 into two roughly equal halves to compare changes in wildfire characteristics over time.

About the Data

Indicator Notes

Many environmental impacts associated with climate change can affect the severity and timing of the wildfire season, including changes in temperature, precipitation, and drought. Short-term weather conditions (dryness, temperature, wind, lightning) influence the likelihood of ignition, where and how quickly a fire spreads, and how big it gets. Longer-term climate patterns also play a role by creating conditions that may be conducive to wildfire (for example, a multi-year regional drought). Human activities and land management practices also affect wildfire activity, and preferred practices in wildfire management have evolved over time, from older policies that favored complete wildfire prevention to more recent policies of wildfire suppression and controlled burns. Resources available to fight and manage wildfires can also influence the amount of area burned over time.

While this indicator is limited to "wildland" fires, it includes fires that encroach on-or perhaps started in-developed areas. Increased development in previously wild lands could also influence trends in wildfire frequency and extent. The total number of fires may also vary due to reporting irregularities, as fires that split or merge together across jurisdictional lines may be counted differently.

Along with the influence of ongoing climate change, wildfire patterns can be influenced by natural climate cycles that tend to shift every few decades. Thus, with less than four decades of data shown here, it might be challenging to draw conclusions about long-term trends. While a longer record would be ideal, data from before 1983 are not consistent or detailed enough nationally to be included in this indicator.

Data Sources

The full set of wildfire frequency and burned acreage data in Figures 1 and 2 comes from the National Interagency Fire Center, which compiles wildfire reports sent from local, state, and federal entities that are involved in fighting fires. These data are available online at: www.nifc.gov/fire-information/statistics. Additional data were provided by the U.S. Forest Service based on a different set of records, referred to as Smokey Bear Reports. Burn severity data, state-by-state acreage totals, and monthly acreage data in Figures 3 through 7 come from the MTBS multi-agency project, which maintains a database of wildfire events across the United States. These data are publicly available at: www.mtbs.gov/direct-download.

Technical Documentation

References

Learn about other indicators in this section

# data[].attributes.attachment_link.title
Climate Change Indicators: Wildfires | US EPA

# data[].attributes.attachment_link.description
This indicator tracks the frequency, extent, and severity of wildfires in the United States.

# data[].attributes.body
1. To what do scientists attribute the recent accelerated sea level rise?
2. What percentage of the population is threatened by rapid sea level rise?

# data[].attributes.attachment_link.title
Study Says 1 Billion Threatened by Sea Level Rise | Worldwatch Institute

# data[].attributes.attachment_link.description
(flood) A sudden swell in sea levels could be catastrophic for more than a billion people living in low-lying areas, according to researchers with the U.S. Geological Survey (USGS).

# data[].attributes.body
Why is sea level rise not uniform?

# data[].attributes.attachment_link.title
State of the Climate: 2011 Global Sea Level | NOAA Climate.gov

# data[].attributes.attachment_link.description
In 2011, global sea levels fell below the long-term trend of sea level rise, but as La Niña waned late in the year, global ocean levels began rising rapidly.

# data[].attributes.body
2. What is the current sea level rise in mm?
3. What is the rate of change per year?

# data[].attributes.attachment_link.provider_name
Climate Change: Vital Signs of the Planet

# data[].attributes.attachment_link.readable_text
101 (± 4.0) mm

This is the "uncertainty margin," or the range from the mean (average) within which there is a high probability that the true number resides. For example, when we say global sea level has risen 101 mm +/- 4 mm, the true value has a high probability of being between 97 and 105 mm. The uncertainty margin exists both because of sea level variability (sea level above the first point in the time series) in the ocean and the accuracy with which we measure the individual values.

Key Takeaway:

Global sea levels are rising as a result of human-caused global warming, with recent rates being unprecedented over the past 2,500-plus years.

Sea level rise is caused primarily by two factors related to global warming: the added water from melting ice sheets and glaciers, and the expansion of seawater as it warms. The first graph tracks the change in global sea level since 1993, as observed by satellites.

The second graph, which is from coastal tide gauge and satellite data, shows how much sea level changed from about 1900 to 2018. Items with pluses (+) are factors that cause global sea level to increase, while minuses (-) are what cause sea level to decrease. These items are displayed at the time they were affecting sea level.

The data shown are the latest available, with a four- to five-month delay needed for processing.

* You now need to create an Earthdata account to access NASA's sea level data. Register here for free. Once logged in, click the "download data" button on this page to access the data.
NASA Sea Level Change

# data[].attributes.attachment_link.description
Vital Signs of the Planet: Global Climate Change and Global Warming. Current news and data streams about global warming and climate change from NASA.

# data[].attributes.headline
Name at least 3 places that would be under water in an iceless world.

# data[].attributes.subject
Name at least 3 places that would be under water in an iceless world.

# data[].attributes.attachment_link.readable_text
This story appears in the September 2013 issue ofNational Geographic magazine.

The maps here show the world as it is now, with only one difference: All the ice on land has melted and drained into the sea, raising it 216 feet and creating new shorelines for our continents and inland seas.

There are more than five million cubic miles of ice on Earth, and some scientists say it would take more than 5,000 years to melt it all. If we continue adding carbon to the atmosphere, we'll very likely create an ice-free planet, with an average temperature of perhaps 80 degrees Fahrenheit instead of the current 58.

North America

The entire Atlantic seaboard would vanish, along with Florida and the Gulf Coast. In California, San Francisco's hills would become a cluster of islands and the Central Valley a giant bay. The Gulf of California would stretch north past the latitude of San Diego-not that there'd be a San Diego.

South America

The Amazon Basin in the north and the Paraguay River Basin in the south would become Atlantic inlets, wiping out Buenos Aires, coastal Uruguay, and most of Paraguay. Mountainous stretches would survive along the Caribbean coast and in Central America.

Compared with other continents, Africa would lose less of its land to the ultimate sea-level catastrophe, but Earth's rising heat might make much of it uninhabitable. In Egypt, Alexandria and Cairo will be swamped by the intruding Mediterranean.

London? A memory. Venice? Reclaimed by the Adriatic Sea. Thousands of years from now, in this catastrophic scenario, the Netherlands will have long since surrendered to the sea, and most of Denmark will be gone too. Meanwhile, the Mediterranean's expanding waters will also have swelled the Black and Caspian Seas.

Land now inhabited by 600 million Chinese would flood, as would all of Bangladesh, population 160 million, and much of coastal India. The inundation of the Mekong Delta would leave Cambodia's Cardamom Mountains stranded as an island.

Predominantly desert, the continent would gain a new inland sea-but it would lose much of the narrow coastal strip where four out of five Australians now live.

Antarctica

East Antarctica: The East Antarctica ice sheet is so large-it contains four-fifths of all the ice on Earth-that it might seem unmeltable. It survived earlier warm periods intact. Lately it seems to be thickening slightly-because of global warming. The warmer atmosphere holds more water vapor, which falls as snow on East Antarctica. But even this behemoth is unlikely to survive a return to an Eocene Climate.

West Antarctica: Like the Greenland ice sheet, the West Antarctic one was apparently much smaller during earlier warm periods. It's vulnerable because most of it sits on bedrock that's below sea level.The warming ocean is melting the floating ice sheet itself from below, causing it to collapse. Since 1992 it has averaged a net loss of 65 million metric tons of ice a year.

# data[].attributes.attachment_link.title
What the World Would Look Like if All the Ice Melted

# data[].attributes.attachment_link.description
This story appears in the September 2013 issue ofNational Geographic magazine. The maps here show the world as it is now, with only one difference: All the ice on land has melted and drained into the sea, raising it 216 feet and creating new shorelines for our continents and inland seas.

# data[].attributes.body
Identify 3 reasons sea levels are rising.

# data[].attributes.attachment_link.readable_text
As humans continue to pour greenhouse gases into the atmosphere, oceans have tempered the effect. The world's seas have absorbed more than 90 percent of the heat from these gases, but it's taking a toll on our oceans: 2021 set a new record for ocean heating.

Rising seas is one of those climate change effects. Average sea levels have swelled over 8 inches (about 23 cm) since 1880, with about three of those inches gained in the last 25 years. Every year, the sea rises another .13 inches (3.2 mm.) Research published in February 2022 shows that sea level rise is accelerating and projected to rise by a foot by 2050.

That translates into as much sea level rise in the next 30 years as occurred over the last century, according to the National Oceanic and Atmospheric Administration. Rick Spinrad, the NOAA administrator, called the findings "historic," and warned that the projected rise will occur even if carbon emissions are drastically cut.

(How carbon dioxide and other greenhouse gases contribute to climate change.)

In the United States, the most vulnerable populations live on the East and Gulf Coasts, where damaging flooding is predicted to occur 10 times more often in 2050 than it does today. The acceleration of sea level rise along these coasts is "unprecedented in at least 120 years," according to a study published in April 2023.

Here's what you need to know about the causes-and consequences-of sea level rise.

Causes of sea level rise

The change in sea levels is linked to three primary factors, all induced by ongoing global climate change:

Thermal expansion: When water heats up, it expands. About half of the sea-level rise over the past 25 years is attributable to warmer oceans simply occupying more space.

Melting glaciers: Large ice formations such as mountain glaciers naturally melt a bit each summer. In the winter, snows, primarily from evaporated seawater, are generally sufficient to balance out the melting. Recently, though, persistently higher temperatures caused by global warming have led to greater-than-average summer melting as well as diminished snowfall due to later winters and earlier springs. That creates an imbalance between runoff and ocean evaporation, causing sea levels to rise.

Loss of Greenland and Antarctica's ice sheets: As with mountain glaciers, increased heat is causing the massive ice sheets that cover Greenland and Antarctica to melt more quickly. Scientists also believe that meltwater from above and seawater from below is seeping beneath Greenland's ice sheets, effectively lubricating ice streams and causing them to move more quickly into the sea. While melting in West Antarctica has drawn considerable focus from scientists, especially with the 2017 break in the Larsen C ice shelf, glaciers in East Antarctica are also showing signs of destabilizing.

Consequences

When sea levels rise as rapidly as they have been, even a small increase can have devastating effects on coastal habitats farther inland, it can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination with salt, and lost habitat for fish, birds, and plants.

(Here's how warming oceans affects wildlife and storm systems.)

Higher sea levels are coinciding with more dangerous hurricanes and typhoons that move more slowly and drop more rain, contributing to more powerful storm surges that can strip away everything in their path. One study found that between 1963 and 2012, almost half of all deaths from Atlantic hurricanes were caused by storm surges.

Already, flooding in low-lying coastal areas is forcing people to migrate to higher ground, and millions more are vulnerable from flood risk and other climate change effects. The prospect of higher coastal water levels threatens basic services such as Internet access, since much of the underlying communications infrastructure lies in the path of rising seas.

Adapting to the threat

As a result of these risks, many coastal cities are already planning adaptation measures to cope with the long-term prospects of higher sea levels, often at considerable cost. Building seawalls, rethinking roads, and planting mangroves or other vegetation to absorb water are all being undertaken.

In Jakarta, a $40 billion project will aim to protect the city with an 80-foot-high seawall. Rotterdam, home to the Global Center on Adaptation, has offered a model to other cities seeking to combat flooding and land loss. The Dutch city has built barriers, drainage, and innovative architectural features such as a "water square" with temporary ponds.

Of course, communities vulnerable to rising seas can only go so far in holding back the tide. In the Marshall Islands, where rising sea levels are forcing a choice between relocating or building up the land, residents will need help from other nations if they decide to undertake the expensive latter option.

How high will it go?

Most predictions say the warming of the planet will continue and is likely to accelerate, causing the oceans to keep rising. This means hundreds of coastal cities face flooding. But forecasting how much and how soon seas will rise remains an area of ongoing research.

A special report from the Intergovernmental Panel on Climate Change says we can expect the oceans to rise between 10 and 30 inches (26 to 77 centimeters) by 2100 with temperatures warming 1.5 °C. That's enough to seriously affect many of the cities along the U.S. East Coast. Another analysis based on NASA and European data skewed toward the higher end of that range, predicting a rise of 26 inches (65 centimeters) by the end of this century if the current trajectory continues.

If all the ice that currently exists on Earth in glaciers and sheets melted it would raise sea level by 216 feet. That could cause entire states and even some countries to disappear under the waves, from Florida to Bangladesh. That's not a scenario scientists think is likely, and it would probably take many centuries, but it could eventually happen if the world keeps burning fossil fuels indiscriminately.

In the meantime, scientists keep refining their models of sea-level changes. They also point out that the extent to which countries work together to limit release of more greenhouse gases may have a significant impact on how quickly seas rise, and how much.

Editor's Note: This story was originally published on February 19, 2019. It has been updated with new data.

# data[].attributes.attachment_link.description
Seas are predicted to rise a foot by 2050, regardless of how much global carbon emissions can be reduced. Why is this happening, and what can we do to adapt?