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Founded in 2002 by Nobel Laureate Carl Wieman, the PhET Interactive Simulations project at the University of Colorado Boulder creates free interactive math and science simulations. PhET sims are based on extensive education research and engage students through an intuitive, game-like environment where students learn through exploration and discovery.

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Quick Look

Grade Level: 4 (3-5)

Time Required: 45 minutes

Lesson Dependency: None

Subject Areas: Earth and Space, Physical Science, Science and Technology

NGSS Performance Expectations:

Summary In this lesson, students are introduced to the five types of renewable energy resources by engaging in various activities to help them understand the transformation of energy (solar, water and wind) into electricity. Students explore the different roles engineers who work in renewable energy fields have in creating a sustainable environment - an environment that contributes to greater health, happiness and safety.
This engineering curriculum aligns to Next Generation Science Standards (NGSS).

Engineering Connection

Engineers have a good understanding about energy, so they can harness renewable resources to create electricity for use in our everyday lives. Mechanical, electrical and civil engineers collaborate to develop new and more efficient ways to generate electricity from renewable resources. They design cleaner-burning engines and new car designs (such as hybrid cars) that require less fuel and result in improved gas mileage which in turns improves our planet.

Learning Objectives

After this lesson, students should be able to:

Describe sources and uses of energy.

Define renewable and non-renewable energy.

Provide examples of common types of renewable and non-renewable resources.

Understand and explain general ways to save energy at a personal, community and global level.

Understand and explain, in general terms, how passive solar heating, hydropower and wind power work.

Describe some general characteristics of solar power, hydropower and wind power.

Understand the benefits and disadvantages to using renewable resources.

Explain how engineers design more efficient ways to use generate electricity.

Describe the role of engineers in energy conservation.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS Performance Expectation

Click to view other curriculum aligned to this Performance Expectation

This lesson focuses on the following Three Dimensional Learning aspects of NGSS:

Science & Engineering Practices

Disciplinary Core Ideas

Crosscutting Concepts

Cause and effect relationships are routinely identified and used to explain change. Knowledge of relevant scientific concepts and research findings is important in engineering. Over time, people's needs and wants change, as do their demands for new and improved technologies.

NGSS Performance Expectation

Click to view other curriculum aligned to this Performance Expectation

This lesson focuses on the following Three Dimensional Learning aspects of NGSS:

Science & Engineering Practices

Disciplinary Core Ideas

Crosscutting Concepts

Energy can be moved from place to place by moving objects or through sound, light, or electric currents. Energy is present whenever there are moving objects, sound, light, or heat. When objects collide, energy can be transferred from one object to another, thereby changing their motion. In such collisions, some energy is typically also transferred to the surrounding air; as a result, the air gets heated and sound is produced. Light also transfers energy from place to place. Energy can also be transferred from place to place by electric currents, which can then be used locally to produce motion, sound, heat, or light. The currents may have been produced to begin with by transforming the energy of motion into electrical energy.

Use multiple resources - including print, electronic, and human - to locate information about different sources of renewable and nonrenewable energy (Grade 4) More Details
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Identify and describe the variety of energy sources (Grade 4) More Details
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Energy comes in many forms such as light, heat, sound, magnetic, chemical, and electrical (Grade 4) More Details
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Introduction/Motivation

Brainstorm a list of ideas about where and when we use energy. (Answer: We use energy all the time. Humans use energy to be active - to walk, talk, play basketball, etc. We use energy to power our appliances, vehicles, lights, etc. Cells use energy to perform the most basic life functions. Life as we know it would not be possible without energy production and consumption.)

Energy is everywhere! Although sometimes you can hear energy (sound), feel energy (wind), taste energy (food), and see energy (light), most often it is hard to figure out exactly where energy is.

Energy can move and change, but it cannot be destroyed. Almost every form of energy can be converted into other forms. It is similar to the heat you feel coming off a light bulb while it is on. The warmth is light energy changed to heat energy. Whatever form it is in, energy is essentially the ability for making something happen or, as scientists put it, "doing work."

Where do we get our energy? Well, a lot of energy originally comes from the sun. We get some energy directly from the sun when we use solar panels; however, most energy comes from fossil fuels (coal and oil), which got their energy from fossilized plants and other organisms that obtained their energy directly from the sun by a process called photosynthesis that occurred many years ago. There are many different types of energy, as we brainstormed earlier. Some of these types of energy are called renewable, or can be re-used, such as energy from the sun, wind or water. Other energy is called non-renewable because once it is used up, it is gone, like coal and oil.

Figure 2. The four sources of non-renewable energy.

Now, imagine yourself having surgery in a hospital and the power goes out. This scenario would be terrible. Fortunately, hospitals have backup generators (designed by engineers!) to prevent this from ever happening. Generators are like storage houses for energy and are usually powered by electricity from coal or fossil fuels. Generators are not normally attached to things like stoplights, railcars or computer networks, which is why we sometimes see stoplights that have gone out. Now, imagine that all of the above mentioned things are backed up with solar energy power or another type of stored renewable energy. This stored power, especially in the form of solar power, never becomes overloaded (which is what happens when the lights in your house or neighborhood go out). The renewable source is always supplying more energy; i.e., the sun is almost always shining on some part of the Earth, wind is always blowing, and rivers are always running. Storing renewable energy for power failures is a better idea because those energy supplies will never run out.

Engineers know all about energy and are currently designing new and more efficient ways to generate electricity using renewable resources. They are designing cleaner engines that use less fuel and new car designs that use electric motors. Today, we are going to look at how engineers can use sun, wind and water power to create electricity to run our homes, cars and everything else. Wow! What incredible engineering creativity!

Lesson Background and Concepts for Teachers

What Is Power?

Energy is the ability to do work (applying a force over a distance), to make things happen, to cause change, or to start motion (a change in position of an object with time). It is the capacity for vigorous activity.

Energy can move (be transferred) and change (be transformed), but it cannot be destroyed. Interactions produce changes in a system, although the total quantities of energy remain unchanged. For example, a power station produces electricity by changing the energy from fuel into electrical energy. A gas-fired power station burns gas, converting the gas' chemical energy into heat. Almost every form of energy can be converted into other forms. But whatever form it is in, energy is essentially the capacity for making something happen or, as scientists put it, "doing work."

Energy comes from many sources, directly or indirectly: power plants, people, food, light, windmills, turbines, fires, electrical circuits, the sun, machines, etc. All energy originally comes from natural resources, most of which originate from the sun.

We use energy to heat houses and buildings, provide light, heating water, break down food, play sports, do activities, operate vehicles, etc.

What are the Different Types of Energy?

Biomass is the combustion of materials that originate from living things.

Chemical is used to fuel automobiles and other vehicles.

Electrical drives many small machines and keeps lights glowing.

Geothermal taps steam from water heated underground (like geysers) and uses it to spin turbines.

Hydrogen power uses electricity to break down water into hydrogen gas. The amount of energy released is less than the energy used to break it apart, so not currently feasible.

Hydroelectricity generates electricity by harnessing the power of flowing water (a renewable resource as long as there is rain). Refer to the associated activity Water Power for students to observe and learn about water related methods of harvesting energy.

Kinetic is the energy of motion. A spinning top, a falling object, and a rolling ball all have kinetic energy. The motion, if resisted by a force, does work. Wind and water both have kinetic energy. Refer to the associated activity Wind Power to give students an understanding of how wind energy is harvested and used.

Light energy is generated from light bulbs and computer screens, the sun.

Nuclear fusion imitates the method the sun uses to produce energy. It involves the joining together of the nuclei of hydrogen atoms.

Nuclear fission is when energy is given off from splitting nuclei of uranium atoms.

Potential energy is the energy stored by an object as a result of its position. For example, roller coaster at the top of a hill.

Sound energy is created, for example, when a door slams, it releases sound energy.

Solar energy occurs from the sun (light). Refer to the associated activity Solar Power for students to explore this energy form.

Thermal energy (or heat) boils water, keeps us warm and drives engines.

Tidal energy is when the energy from ocean tides is harnessed.

Other energy sources, for example, include energy created from old car tires: this source fuels five power stations in the U.S. Also, engineers are trying to design new gas power stations (gas drives the electricity generators and then is reused to heat the plant). Lastly, methane that is produced in sanitary landfills may be used to make power.

How are Energy Sources Categorized?

Non-Renewable Energy Sources Renewable Energy Sources

Natural gas

Wind

Coal

Water

Oil

Solar

Other Fossil Fuels

What are Engineers Doing to Improve Our Energy Sources?

Current uses of fossil fuels have catastrophic effects on our environment. Obtaining and using them destroys natural habitats and pollutes the air, water, and land. We can reduce this consumption of fossil fuels by finding alternative, renewable methods of energy production. Engineers are involved in many new technologies that will save our precious resources from devastating long-term effects.

And, engineers are improving the design of factories and products to make even more efficient use of our resources. They are designing cleaner engines that use less fuel and new car designs that run by electric motors. They are studying corals because they very efficiently use low levels of phosphate in the water for energy. Corals have fractal surfaces, and scientists believe that fractal surfaces could make many chemical reactions more efficient. They are working to make machines smaller and more efficient (industrial engineers/designers). For example, they developed fiber optics (thin glass cables to replace heavy metal ones for phones). These efforts contribute to a better, cleaner planet for all inhabitants. Wouldn't it be great to be an engineer making such an important difference in our lives?

Associated Activities

Lesson Closure

Ask the students to describe some sources of renewable energy? (Answer: sun, wind, water) Can they list three specific ways that engineers are involved with renewable resources? (Possible answers: engineers study renewable resources to develop better ways to use these resources for energy generation; engineers design cars that run off renewable resources; engineers design generators that store the energy gathered from renewable resources; engineers develop wind farms to generate electricity for us to use; engineers develop hydropower plants to generate electricity for us to use; engineers are developing machines that are more efficient to reduce the amount of energy, renewable or non-renewable, that gets used; and engineers work to inform communities about what they can do to help conserve energy and use renewable resources.) Engineers work at developing new technologies that use renewable sources to contribute to greater health, happiness and safety of our Earth's inhabitants.

Vocabulary/Definitions

absorb: To be taken into a material without transmission or reflection.

active solar system: Solar power systems that use electrical or mechanical components, such as fans, pumps, and electrical controls in circulating fluids. These systems can be used for heating water or heating/cooling buildings.

anemometer: An instrument for measuring the velocity of wind.

convection: The transfer of thermal energy in a fluid (gas or liquid) by the circulation of currents in the heated fluid causing warmer packets to rise while cooler packets sink.

electromagnetic radiation: Electromagnetic energy transmitted in the form of waves or particles (photons); the electromagnetic spectrum, in order of increasing energy: radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, gamma rays, cosmic-ray photons.

generator: A device that transforms mechanical energy into electrical energy.

heat exchanger: A device, such as an automobile radiator, that transfers heat from one liquid to another without allowing them to mix.

heat-transfer fluid: A fluid circulated in a heat exchanger; this fluid gains energy from one region and transfers it to another region.

hydraulic head: The difference in depth of a liquid at two given points; the pressure of the liquid at the lower point expressed in terms of this difference.

insulation: A material used to prevent the passage of heat, electricity, or sound (i.e., a non-conducting material).

passive solar system: Solar power systems that do not require electrical or mechanical components; these systems can be used for heating water or heating/cooling buildings.

penstock: A pipe or conduit used to carry water to a water wheel or turbine.

photovoltaic system: This is a system which converts solar energy into electricity.

reflect: This is when something such as sound waves or light waves bend back or return upon striking a surface.

regenerate: To re-grow or replace.

renewable energy: Energy that is made from sources that can be regenerated or reused is renewable.

rotor: The rotating part of an electrical or mechanical device is the rotor.

thermal mass: Materials that store thermal energy, such as water, concrete, brick, stone, adobe, tile, etc.

transmit: To allow the passage through a material.

turbine: A machine in which the kinetic energy of a moving fluid is converted into mechanical energy by causing a series of buckets, paddles, or blades on a rotor to rotate.

Assessment

Pre-lesson assessment

Brainstorming: Ask students to brainstorm ideas about where and when we use energy. (Possible answers: We use energy all the time. Humans use energy to be active - to walk, talk, play basketball, etc. We use energy to power our appliances, vehicles, lights, etc. Cells use energy to perform the most basic life functions. Life as we know it would not be possible without energy production and consumption.)

Post-introduction assessment

Guess the Amount!: Ask students the following questions and ask them to guess at the different percentages of energy use. Discuss and explain the answers.

What percent of the energy the world uses today is derived from fossil fuels (e.g., coal, oil, natural gas)? (Answer: 80-85%. This means that only 15-20% of the energy we use is from renewable energy sources such as sun, wind and water.)

The U.S. has less than 5% of the world's population. What percent of the world's energy do we use? (Answer: Around 17%. This means that the U.S. uses a lot more energy than other countries. Why do the students think that is? Discuss the amount of toys, appliances and other electric powered items in a single person's home.)

What percent of the electricity consumed in the U.S. is used for light bulbs? (Answer: 5%. This means that we leave a lot of light bulbs on when unused. Can the students think of a time where they could save some electricity by turning off a light bulb?)

Discussion: Ask students the following questions. Discuss the answers.

How do we know the energy is there? (Answer: We can see it, feel it, hear it, etc.)

Ask students to describe where this energy comes from. (Answer: ultimately all of it comes from natural resources (renewable and non-renewable), but it is often moved (transferred) and changed (transformed) in the process. You may want to give an example here like coal being mined from the earth, sent to power plants where it is burned to produce steam. The steam turns a turbine and produces electricity that is sent to our houses via power lines, and used in our electrical items like a refrigerator. Or how solar energy is used by plants to create food so they can grow and then we, in turn, use the plants as food to provide energy for our bodies.)

Ask students to describe where they get their energy. (Answer: from food) Ask them to describe what might happen if suddenly there was no more food. (Note: this is a stretch for some because generally food is considered a renewable resource and because the food supply often seems unlimited to people in the U.S.). What would they do? (Answer: Become hungry, eventually starve, engineer some new source of nutrients, etc.) How would they feel? (Answer: Hungry, sad, scared, motivated to find a way to survive, etc.)

What if there was only a tiny bit of food? How would it get distributed? Who would decide? What are some other consequences? (Answer: equal world-wide distribution, war, the rich get it, others die, new source of nutrients discovered/engineered, etc.)

Lesson summary assessment

Future Timeline: Ask students to work in a group to imagine what today would be like if there were no electricity (permanently, not just a blackout situation). Ask them to develop a timeline describing what this typical day might be like. Ask them to really consider how they would feel and what they would do. Ask each group to present their timeline to the class.

Venn Diagram: Ask students to create a Venn Diagram to compare/contrast a form of renewable energy and a form of non-renewable energy. They should provide as many facts and details as they can.

Homework

Save a Watt: Ask students to engage in two energy saving activities before the next class period. Ask them to describe in detail the impact these actions had during the next class. You can have the students list the activities or write a paragraph and turn the assignment in.

Lesson Extension Activities

Write and illustrate a children's story for 8-10 year olds about life in the year 2100. It should describe life without fossil fuels and should identify the energy sources used in everyday life as well as some type of conservation measures.

Discuss what is happening with our world energy supply from fossil fuels and other non-renewable resources. (Examples: fossil fuels are being dangerously depleted, the rich countries receive a larger share of the energy and are more wasteful with it, wars are developing; e.g., the Gulf War, scientists and engineers are researching and developing renewable energy sources, etc.)

Check out the awesome information and activities/games at Environmental Education for Kids (EEK) website from Wisconsin Department of Natural Resources at dnr.wi.gov

Check out some of the activities at Watt Watchers: https://www.watt-watchers.com/student-activities/

Check out some of the activities and games about energy online

1. Play energy-themed games at NASA's Climate Kids website: https://climatekids.nasa.gov/menu/energy/

2. Learn more about renewable energy at Alliant Energy's website: https://www.alliantenergykids.com/RenewableEnergy/RenewableEnergyHome

3. Read, color, and solve puzzles in the "Saving Energy in My Home Coloring and Activity Book" at https://extension.colostate.edu/docs/pubs/consumer/saving-energy-home.pdf

4. Try a Nuclear Chain Reaction activity at http://nuclearconnect.org/in-the-classroom/for-teachers/nuclear-chain-reaction-using-dominoes

References

American Wind Association, www.awea.org

Boulder Community Network, Environmental Center, bcn.boulder.co.us/environment/

California Energy Commission, www.energyquest.ca.gov/

Energy Information Administration, Energy Kid's Page, www.eia.gov/kids/

Hewitt, Paul G. Conceptual Physics, Boston, MA: Addison Wesley Publishing Company, 2004.

Goswami, D. Yogi, Kreith, Frank, and Kreider, Jan F. Principles of Solar Engineering, Taylor & Francis Group, 2nd edition, 2000.

Graham, Ian, Taylor, Barbara, Fardon, John, Oxlad, Chris and Parker, Steve. Science Encyclopedia, Miles Kelly, 2000.

Milton Hydro, https://www.miltonhydro.com/Residential/Community/Power-Kids

National Renewable Energy Laboratory, www.nrel.gov

Snow, Theodore. The Dynamic Universe: An Introduction to Astronomy, Minnesota: West Publishing Company, 1988.

Steen, Anthena S., Steen, Bill, Bainbridge, David and Eisenberg. The Straw Bale House, Vermont: Chelsea Green Publishing Company, 1994.

Texas State Energy Conservation Office, www.infinitepower.org/lessonplans.htm

U.S. Department of Energy, energy.gov

U.S. Department of Energy, Energy Efficiency and Renewable Energy, www.eere.energy.gov

Copyright © 2005 by Regents of the University of Colorado.

Contributors Amy Kolenbrander; Jessica Todd; Malinda Schaefer Zarske; Janet Yowell

Supporting Program Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder

Acknowledgements

The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: November 17, 2021

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In this lesson, students are introduced to the five types of renewable energy resources by engaging in various activities to help them understand the transformation of energy (solar, water and wind) into electricity. Students explore the different roles engineers who work in renewable energy fields have in creating a sustainable environment - an environment that contributes to greater health, happiness and safety.

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U.S. Environmental Protection Agency (.gov)

https://www.epa.gov › coral-reefs › threats-coral-reefs

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Fishing is one of the most significant drivers of declines in ocean wildlife populations. Catching fish is not inherently bad for the ocean, except for when vessels catch fish faster than stocks can replenish, something called overfishing.

The number of overfished stocks globally has tripled in half a century and today fully one-third of the world's assessed fisheries are currently pushed beyond their biological limits, according to the Food and Agriculture Organization of the United Nations. Overfishing is closely tied to bycatch -the capture of unwanted sea life while fishing for a different species. This, too, is a serious marine threat that causes the needless loss of billions of fish, along with hundreds of thousands of sea turtles and cetaceans.

The damage done by overfishing goes beyond the marine environment. Billions of people rely on fish for protein, and fishing is the principal livelihood for millions of people around the world.

Many people who make a living catching, selling, and buying fish are working to improve how the world manages and conserves ocean resources. WWF works with a cross-section of stakeholders to reform fisheries management globally, focusing on sustainable practices that not only conserve ecosystems, but also sustain livelihoods and ensure food security.

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Fishing is one of the most significant drivers of declines in ocean wildlife populations. Catching fish is not inherently bad for the ocean, except for when vessels catch fish faster than stocks can replenish, something called overfishing.

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We're often asked how armed conflicts harm the environment. In this blog we try to provide as many different examples of harms as we can. It's intended as a non-exhaustive introduction that follows the cycle of conflicts, and has links for further reading. Critically, environmental damage has implications for people, as well as ecosystems. This means that protecting civilians first requires that we protect the environment that they depend upon.

For information on the environmental dimensions of the conflict in Ukraine, visit our dedicated Ukraine page.

Environmental damage before conflicts

The environmental impact of wars begins long before they do. than many of the world's countries combined. We Building and sustaining military forces consumes vast quantities of resources. These might be common metals or rare earth elements, water or hydrocarbons. Maintaining military readiness means training, and training consumes resources. Military vehicles, aircraft, vessels, buildings and infrastructure all require energy, and more often than not that energy is oil, and energy efficiency is low. The emissions of the largest militaries CO estimate that militaries are responsible for 5.5% of all greenhouse gas emissions globally, however military emissions reporting to the UN Framework Convention on Climate Change is poor. ₂ are greater

Militaries also need large areas of land and sea, whether for bases and facilities, or for testing and training. . While excluding public development from these areas can benefit biodiversity, the question of whether they could be better managed as civil protected areas is rarely discussed. Military lands are believed to cover between 1-6% of the global land surface. In many cases these are ecologically important areas Military training creates emissions, disruption to landscapes and terrestrial and marine habitats, and creates chemical and noise pollution from the use of weapons , aircraft and vehicles .

Sustaining and renewing military equipment and materiel means ongoing disposal costs, with implications for the environment. It is not just the most hazardous nuclear and chemical weapons that create environmental problems throughout their lifecycle . The same is also true for conventional weapons, particularly where they are disposed of through open burning or detonation. Historically, vast quantities of surplus munitions were also dumped at sea .

A history of weak environmental oversight has left many countries with serious environmental linked to for environmental remediation. These continue to grow as emerging pollutants like legacies military pollution, with impacts on public health and vast costs PFAS are identified. These legacies are also a problem around overseas bases where one-sided agreements with host nations can reduce environmental oversight.

Indirectly, high levels of military spending diverts resources away from solving environmental problems and away from sustainable development. International tensions stoked by high levels of military spending also reduce opportunities for international cooperation on global environmental threats, such as the climate emergency. It is also important to consider how security policies and militarism are tailored to ensuring access to, and control of, natural resources like oil, gas, water and metals.

Environmental damage during conflicts

The environmental impact of conflicts themselves vary greatly . Some international armed conflicts may be brief but highly destructive. Some civil wars may last for decades but be fought at low intensity. Many contemporary conflicts have blurred the lines, lasting years but with sustained periods of high intensity warfare. Who is fighting, where they're fighting and how they're fighting all strongly influence the environmental impact of a conflict.

High intensity conflicts require and consume vast quantities of fuel, leading to massive CO₂ emissions and contributing to climate change. Large scale vehicle movements can lead to widespread physical damage to sensitive landscapes and geodiversity, as can the intensive use of explosive ordnance. The use of explosive weapons in urban areas creates vast quantities of debris and rubble, which can cause air and soil pollution. Pollution can also be caused by damage to light industry and environmentally sensitive infrastructure such as water treatment plants. The loss of energy supplies can have reverberating effects that are detrimental to the environment, shutting down treatment plants or pumping systems, or can lead to the use of more polluting fuels or domestic generators.

Severe can be caused when , to pollute large areas and spread terror. Other pollution incidents industrial, oil or energy facilities are deliberately attacked, inadvertently damaged or disrupted. In some cases, deliberate attacks on oil or industrial facilities are used as a weapon of war scorched earth techniques include the destruction of agricultural infrastructure like canals, wells and pumps and the burning of crops. Tactics like these threaten food security and livelihoods, increasing the vulnerability of rural communities. Whether unintended or deliberate, these large-scale pollution incidents can lead to transboundary impacts from air pollution or through the contamination of rivers, aquifers or the sea. In some instances, these even have the potential to affect weather or the global climate.

Weapons and military materiel used during conflicts also leave environmental legacies. , cluster munitions and other can cause Land mines explosive remnants of war can restrict access to agricultural land and pollute soils and water sources with metals and toxic energetic materials. In major conflicts, large volumes of military scrap may be produced or abandoned, this can contain a range of polluting materials, contaminating soils and groundwater, whilst exposing those who work on it to acute and chronic health risks. Wrecked or damaged ships , submarines and offshore oil infrastructure marine pollution.

Many conventional weapons have toxic constituents, others such as depleted uranium are also radioactive. Incendiary weapons such as white phosphorous are not only toxic but can also damage habitats through fire . While now restricted, the widespread use of chemical defoliants damaged public and ecological health across large areas of Vietnam.

Easy access to small arms and light weapons can harm wildlife through to have been sourced from countries affected by conflict. Scientists and researchers may be unable to access areas due to security problems, harming facilitating increased hunting and poaching, and the ungoverned spaces created by conflict create the ideal conditions for wildlife crime. Weapons used in wildlife crime have been found conservation programmes. While national parks and protected areas may lose what protection they had, or protecting them may be made more difficult when poachers are armed. These situations can encourage more militarised conservation , which can have negative effects on relationships with local communities.

of the collapse of management systems. Deforestation often increases during conflicts. Much of the time this is due to overharvesting by communities who are suddenly reliant on wood and charcoal for fuel and heating. But it can also be as a result of armed or criminal gangs taking advantage Civilian coping strategies can also lead to the overharvesting of other natural resources or to environmentally damaging practices such as artisanal oil refining . And in some cases, community systems of sustainable resource management may be disrupted.

Environmental damage and degradation can also stem from resource extraction used to finance conflicts. In many conflicts, armed groups vie for control over oil, mineral resources or timber . Processing methods, such as the use of mercury in gold mining, can pollute water bodies. In addition to armed groups and artisanal workers, private companies may also be active in areas affected by conflict, often operating with minimal environmental oversight.

Human displacement is common to many conflicts. Camps for refugees and internally displaced peoples can have large environmental footprints , particularly where they are unplanned or lack essential services, like water, sanitation and waste management. Their location is also important, as camp residents may be compelled to use local resources such as firewood, which can place local resources under pressure. People displaced by conflict may also move internally to urban areas, swelling the population and placing local environmental services under strain.

In some cases, the areas where displaced people move through may be placed under pressure, for example herders moving their livestock through sensitive ecosystems. Large scale refugee movements can also create transboundary environmental impacts, when areas in neighbouring countries struggle to cope with the influx of people and with meeting their basic needs.

One basic need common to displacement camps and to urban areas experiencing conflict is . Systems often break down during conflict leading to increased rates of of waste management waste dumping and burning, improper management and less waste segregation. Waste management systems are just one element of environmental governance that may collapse during conflicts. Local environmental laws and regulations may be ignored, and local and national administrations may lose their capacity to monitor, assess or respond to environmental problems. New administrations may also emerge in areas that are held by non-state actors, and whose approach to environmental governance may differ markedly from that of the government. In recent years there has been a growing trend towards the weaponisation environmental information during conflicts, leading to the increased politicisation of environmental risks.

Governments may be unable to meet their , particularly because international environmental obligations projects and programmes supported by the international community may be curtailed. In this way a localised conflict may harm the environment nationally by impacting governance and projects countrywide. The existence of a conflict can also create serious technological risks from industrial infrastructure , and then hamper the international cooperation required to address them.

These diverse impacts on the environment mean that conflicts are often viewed as sustainable development in reverse , and may set countries back years. Not just because of new damage, but in the development that would have taken place were it not for the existence of a conflict. But is it all negative? There are times where the existence of conflict can confer protection to areas, for example by slowing unsustainable development that would otherwise have taken place in areas that are insecure, or by excluding human activities due to the presence of explosive remnants of war. But overall, and particularly because of the disruption conflicts cause to societies and to governance, the harms far outweigh the benefits.

Environmental damage during occupations

Occupations may be relatively short-lived, or can last decades. While states have an obligation to protect the occupied population, their environmental obligations are less well defined. As with conflicts, occupations can hold back sustainable development, for example by limiting access to materials or technologies, or by acting as a barrier to investment. Pre-existing environmental programmes and projects may be curtailed, or replaced by a new incoming administration.

A lack of investment and development can lead to the the occupier can also lead to environmental harm. The increased slow collapse of critical environmental infrastructure , infrastructure that may be damaged or degraded by periods of violence. Measures taken by the occupied population to oppose military presence can impact landscapes by vehicle movements or training areas, or by the building of walls and fences that can disrupt wildlife movements, or separate people from the resources they are dependent on. Poor waste management at military bases, whether operated by states or private contractors, can harm public health and the environment. Meanwhile, militarised responses to security issues can create more serious environmental harm than civil responses would.

is common to occupations, with Inequitable resource management resource grabs and over-extraction common, whether of water or minerals. Environmental oversight can be limited or preferential, facilitating environmental degradation. The occupied population may be unable to enjoy the same environmental human rights as those of the occupier, and be forced to live with limited resources, poorer environmental services and higher levels of pollution.

Politically focused is common as the occupying power seeks to make its mark on a territory. In this way development major infrastructure works may be undertaken with little environmental oversight.

Environmental damage after conflicts

It is rare these days for conflicts to conclude cleanly with a peace agreement and a ceasefire. Low level conflict and insecurity can continue for long periods. In this respect many of the forms of harm that occur during conflicts are also applicable to this phase, particularly in its early stages.

Transitions to peace are typified by weak state control, this means that environmental governance, and the capacity to provide it is often absent. Attention to environmental issues in the face of many competing social and economic priorities is usually limited. These conditions are key to many post-conflict environmental problems. In some instances, peace and power sharing agreements have impeded governance by creating fragmented political systems .

In the immediate aftermath of conflicts, states and international actors may be faced with of industrial sites has exposed communities to pollutants, and many of the environmentally immediate legacies, such as vast quantities of rubble and debris . If managed poorly, for example through informal dumping, disposal can create new environmental risks. There have been instances where the looting harmful coping strategies that people used to survive during conflicts may continue well beyond their end.

In conflicts with high levels of displacement, are common, particularly when returnees move home. Influxes of people can increase . Research has shown a sharp increase in land rights and ownership issues environmental pressures in areas from which they have been absent, particularly through agricultural conversion or expansion. This can lead to increased rates of deforestation deforestation rates in many post-conflict countries, with clearance outpacing the state's ability to control it.

The presence of , particularly where the host nation may be unable to enforce environmental standards. The use of practices like military forces can extend well into the post-conflict phase. The operation and ultimate closure or handover of bases are associated with pollution issues burn pits has exposed military personnel and communities to hazardous pollution, leaving veterans with ongoing health problems. The post-conflict clearance of landmines and explosive remnants of war can lead to soil degradation and localised pollution, and negative changes in land use when areas are released back to communities.

The damage that conflicts do to environmental governance can have implications for environmental protection for years. This can set back progress on issues as diverse as pollution control, resource and protected area management, climate change adaptation and biodiversity protection. Finally, the environmental costs of recovery may be significant. Massive urban rebuilding projects can require huge volumes of resources.

Environmental opportunities

While armed conflicts and military activities can cause or facilitate many different forms of environmental harm, addressing the environment during and after conflicts can also create opportunities for building and sustaining peace, and for helping to transform societies through sustainable recovery.

Shared natural resources can provide the basis for dialogue between warring parties, as can common environmental threats that extend across human boundaries and borders. Unpredictable energy supplies during conflicts can encourage a transition to solar power , while the devastation conflicts cause can be an opportunity to build back greener, or to create new domestic legal frameworks to sustainably manage resources.

However, these opportunities are dependent on more attention being paid to the environment before, during and after conflicts. If we fail to call for greater protection before and during conflicts, damage will be seen as acceptable. And if we ignore the environment after conflicts, we will not only miss out on opportunities to encourage sustainable recovery, we may also be setting states up for future resource conflicts.
Doug Weir is CEOBS' Research and Policy Director

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How does war damage the environment? - CEOBS

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Ever wondered what the environmental impacts of war are? Read our guide to the many different ways through which armed conflicts and militarism can damage the environment.

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What is carbon sequestration? | U.S. Geological Survey

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Carbon dioxide is the most commonly produced greenhouse gas. Carbon sequestration is the process of capturing and storing atmospheric carbon dioxide. It is one method of reducing the amount of carbon dioxide in the atmosphere with the goal of reducing global climate change. The USGS is conducting as…

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Pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants. Pollutants can be natural, such as volcanic ash. They can also be created by human activity, such as trash or runoff produced by factories. Pollutants damage the quality of air, water, and land.

Many things that are useful to people produce pollution. Cars spew pollutants from their exhaust pipes. Burning coal to create electricity pollutes the air. Industries and homes generate garbage and sewage that can pollute the land and water. Pesticides-chemical poisons used to kill weeds and insects-seep into waterways and harm wildlife.

All living things-from one-celled microbes to blue whales-depend on Earth's supply of air and water. When these resources are polluted, all forms of life are threatened.

Pollution is a global problem. Although urban areas are usually more polluted than the countryside, pollution can spread to remote places where no people live. For example, pesticides and other chemicals have been found in the Antarctic ice sheet. In the middle of the northern Pacific Ocean, a huge collection of microscopic plastic particles forms what is known as the Great Pacific Garbage Patch.

Air and water currents carry pollution. Ocean currents and migrating fish carry marine pollutants far and wide. Winds can pick up radioactive material accidentally released from a nuclear reactor and scatter it around the world. Smoke from a factory in one country drifts into another country.

In the past, visitors to Big Bend National Park in the U.S. state of Texas could see 290 kilometers (180 miles) across the vast landscape. Now, coal-burning power plants in Texas and the neighboring state of Chihuahua, Mexico have spewed so much pollution into the air that visitors to Big Bend can sometimes see only 50 kilometers (30 miles).

The three major types of pollution are air pollution, water pollution, and land pollution.

Air Pollution
Sometimes, air pollution is visible. A person can see dark smoke pour from the exhaust pipes of large trucks or factories, for example. More often, however, air pollution is invisible.

Polluted air can be dangerous, even if the pollutants are invisible. It can make people's eyes burn and make them have difficulty breathing. It can also increase the risk of lung cancer.

Sometimes, air pollution kills quickly. In 1984, an accident at a pesticide plant in Bhopal, India, released a deadly gas into the air. At least 8,000 people died within days. Hundreds of thousands more were permanently injured.

Natural disasters can also cause air pollution to increase quickly. When volcanoes erupt, they eject volcanic ash and gases into the atmosphere. Volcanic ash can discolor the sky for months. After the eruption of the Indonesian volcano of Krakatoa in 1883, ash darkened the sky around the world. The dimmer sky caused fewer crops to be harvested as far away as Europe and North America. For years, meteorologists tracked what was known as the "equatorial smoke stream." In fact, this smoke stream was a jet stream, a wind high in Earth's atmosphere that Krakatoa's air pollution made visible.

Volcanic gases, such as sulfur dioxide, can kill nearby residents and make the soil infertile for years. Mount Vesuvius, a volcano in Italy, famously erupted in 79, killing hundreds of residents of the nearby towns of Pompeii and Herculaneum. Most victims of Vesuvius were not killed by lava or landslides caused by the eruption. They were choked, or asphyxiated, by deadly volcanic gases.

In 1986, a toxic cloud developed over Lake Nyos, Cameroon. Lake Nyos sits in the crater of a volcano. Though the volcano did not erupt, it did eject volcanic gases into the lake. The heated gases passed through the water of the lake and collected as a cloud that descended the slopes of the volcano and into nearby valleys. As the toxic cloud moved across the landscape, it killed birds and other organisms in their natural habitat. This air pollution also killed thousands of cattle and as many as 1,700 people.

Most air pollution is not natural, however. It comes from burning fossil fuels-coal, oil, and natural gas. When gasoline is burned to power cars and trucks, it produces carbon monoxide, a colorless, odorless gas. The gas is harmful in high concentrations, or amounts. City traffic produces highly concentrated carbon monoxide.

Cars and factories produce other common pollutants, including nitrogen oxide, sulfur dioxide, and hydrocarbons. These chemicals react with sunlight to produce smog, a thick fog or haze of air pollution. The smog is so thick in Linfen, China, that people can seldom see the sun. Smog can be brown or grayish blue, depending on which pollutants are in it.

Smog makes breathing difficult, especially for children and older adults. Some cities that suffer from extreme smog issue air pollution warnings. The government of Hong Kong, for example, will warn people not to go outside or engage in strenuous physical activity (such as running or swimming) when smog is very thick.

When air pollutants such as nitrogen oxide and sulfur dioxide mix with moisture, they change into acids. They then fall back to earth as acid rain. Wind often carries acid rain far from the pollution source. Pollutants produced by factories and power plants in Spain can fall as acid rain in Norway.

Acid rain can kill all the trees in a forest. It can also devastate lakes, streams, and other waterways. When lakes become acidic, fish can't survive. In Sweden, acid rain created thousands of "dead lakes," where fish no longer live.

Acid rain also wears away marble and other kinds of stone. It has erased the words on gravestones and damaged many historic buildings and monuments. The Taj Mahal, in Agra, India, was once gleaming white. Years of exposure to acid rain has left it pale.

Governments have tried to prevent acid rain by limiting the amount of pollutants released into the air. In Europe and North America, they have had some success, but acid rain remains a major problem in the developing world, especially Asia.

Greenhouse gases are another source of air pollution. Greenhouse gases such as carbon dioxide and methane occur naturally in the atmosphere. In fact, they are necessary for life on Earth. They absorb sunlight reflected from Earth, preventing it from escaping into space. By trapping heat in the atmosphere, they keep Earth warm enough for people to live. This is called the greenhouse effect.

But human activities such as burning fossil fuels and destroying forests have increased the amount of greenhouse gases in the atmosphere. This has increased the greenhouse effect, and average temperatures across the globe are rising. The decade that began in the year 2000 was the warmest on record. This increase in worldwide average temperatures, caused in part by human activity, is called global warming.

Global warming is causing ice sheets and glaciers to melt. The melting ice is causing sea levels to rise at a rate of two millimeters (0.09 inches) per year. The rising seas will eventually flood low-lying coastal regions. Entire nations, such as the islands of Maldives, are threatened by this climate change.

Global warming also contributes to the phenomenon of ocean acidification. Ocean acidification is the process of ocean waters absorbing more carbon dioxide from the atmosphere. Fewer organisms can survive in warmer, less salty waters. The ocean food web is threatened as plants and animals such as coral fail to adapt to more acidic oceans.

Scientists have predicted that global warming will cause an increase in severe storms. It will also cause more droughts in some regions and more flooding in others.

The change in average temperatures is already shrinking some habitats, the regions where plants and animals naturally live. Polar bears hunt seals from sea ice in the Arctic. The melting ice is forcing polar bears to travel farther to find food, and their numbers are shrinking.

People and governments can respond quickly and effectively to reduce air pollution. Chemicals called chlorofluorocarbons (CFCs) are a dangerous form of air pollution that governments worked to reduce in the 1980s and 1990s. CFCs are found in gases that cool refrigerators, in foam products, and in aerosol cans.

CFCs damage the ozone layer, a region in Earth's upper atmosphere. The ozone layer protects Earth by absorbing much of the sun's harmful ultraviolet radiation. When people are exposed to more ultraviolet radiation, they are more likely to develop skin cancer, eye diseases, and other illnesses.

In the 1980s, scientists noticed that the ozone layer over Antarctica was thinning. This is often called the "ozone hole." No one lives permanently in Antarctica. But Australia, the home of more than 22 million people, lies at the edge of the hole. In the 1990s, the Australian government began an effort to warn people of the dangers of too much sun. Many countries, including the United States, now severely limit the production of CFCs.

Water Pollution
Some polluted water looks muddy, smells bad, and has garbage floating in it. Some polluted water looks clean, but is filled with harmful chemicals you can't see or smell.

Polluted water is unsafe for drinking and swimming. Some people who drink polluted water are exposed to hazardous chemicals that may make them sick years later. Others consume bacteria and other tiny aquatic organisms that cause disease. The United Nations estimates that 4,000 children die every day from drinking dirty water.

Sometimes, polluted water harms people indirectly. They get sick because the fish that live in polluted water are unsafe to eat. They have too many pollutants in their flesh.

There are some natural sources of water pollution. Oil and natural gas, for example, can leak into oceans and lakes from natural underground sources. These sites are called petroleum seeps. The world's largest petroleum seep is the Coal Oil Point Seep, off the coast of the U.S. state of California. The Coal Oil Point Seep releases so much oil that tar balls wash up on nearby beaches. Tar balls are small, sticky pieces of pollution that eventually decompose in the ocean.

Human activity also contributes to water pollution. Chemicals and oils from factories are sometimes dumped or seep into waterways. These chemicals are called runoff. Chemicals in runoff can create a toxic environment for aquatic life. Runoff can also help create a fertile environment for cyanobacteria, also called blue-green algae. Cyanobacteria reproduce rapidly, creating a harmful algal bloom (HAB). Harmful algal blooms prevent organisms such as plants and fish from living in the ocean. They are associated with "dead zones" in the world's lakes and rivers, places where little life exists below surface water.

Mining and drilling can also contribute to water pollution. Acid mine drainage (AMD) is a major contributor to pollution of rivers and streams near coal mines. Acid helps miners remove coal from the surrounding rocks. The acid is washed into streams and rivers, where it reacts with rocks and sand. It releases chemical sulfur from the rocks and sand, creating a river rich in sulfuric acid. Sulfuric acid is toxic to plants, fish, and other aquatic organisms. Sulfuric acid is also toxic to people, making rivers polluted by AMD dangerous sources of water for drinking and hygiene.

Oil spills are another source of water pollution. In April 2010, the Deepwater Horizon oil rig exploded in the Gulf of Mexico, causing oil to gush from the ocean floor. In the following months, hundreds of millions of gallons of oil spewed into the gulf waters. The spill produced large plumes of oil under the sea and an oil slick on the surface as large as 24,000 square kilometers (9,100 square miles). The oil slick coated wetlands in the U.S. states of Louisiana and Mississippi, killing marsh plants and aquatic organisms such as crabs and fish. Birds, such as pelicans, became coated in oil and were unable to fly or access food. More than two million animals died as a result of the Deepwater Horizon oil spill.

Buried chemical waste can also pollute water supplies. For many years, people disposed of chemical wastes carelessly, not realizing its dangers. In the 1970s, people living in the Love Canal area in Niagara Falls, New York, suffered from extremely high rates of cancer and birth defects. It was discovered that a chemical waste dump had poisoned the area's water. In 1978, 800 families living in Love Canal had to abandon their homes.

If not disposed of properly, radioactive waste from nuclear power plants can escape into the environment. Radioactive waste can harm living things and pollute the water.

Sewage that has not been properly treated is a common source of water pollution. Many cities around the world have poor sewage systems and sewage treatment plants. Delhi, the capital of India, is home to more than 21 million people. More than half the sewage and other waste produced in the city are dumped into the Yamuna River. This pollution makes the river dangerous to use as a source of water for drinking or hygiene. It also reduces the river's fishery, resulting in less food for the local community.

A major source of water pollution is fertilizer used in agriculture. Fertilizer is material added to soil to make plants grow larger and faster. Fertilizers usually contain large amounts of the elements nitrogen and phosphorus, which help plants grow. Rainwater washes fertilizer into streams and lakes. There, the nitrogen and phosphorus cause cyanobacteria to form harmful algal blooms.

Rain washes other pollutants into streams and lakes. It picks up animal waste from cattle ranches. Cars drip oil onto the street, and rain carries it into storm drains, which lead to waterways such as rivers and seas. Rain sometimes washes chemical pesticides off of plants and into streams. Pesticides can also seep into groundwater, the water beneath the surface of the Earth.

Heat can pollute water. Power plants, for example, produce a huge amount of heat. Power plants are often located on rivers so they can use the water as a coolant. Cool water circulates through the plant, absorbing heat. The heated water is then returned to the river. Aquatic creatures are sensitive to changes in temperature. Some fish, for example, can only live in cold water. Warmer river temperatures prevent fish eggs from hatching. Warmer river water also contributes to harmful algal blooms.

Another type of water pollution is simple garbage. The Citarum River in Indonesia, for example, has so much garbage floating in it that you cannot see the water. Floating trash makes the river difficult to fish in. Aquatic animals such as fish and turtles mistake trash, such as plastic bags, for food. Plastic bags and twine can kill many ocean creatures. Chemical pollutants in trash can also pollute the water, making it toxic for fish and people who use the river as a source of drinking water. The fish that are caught in a polluted river often have high levels of chemical toxins in their flesh. People absorb these toxins as they eat the fish.

Garbage also fouls the ocean. Many plastic bottles and other pieces of trash are thrown overboard from boats. The wind blows trash out to sea. Ocean currents carry plastics and other floating trash to certain places on the globe, where it cannot escape. The largest of these areas, called the Great Pacific Garbage Patch, is in a remote part of the Pacific Ocean. According to some estimates, this garbage patch is the size of Texas. The trash is a threat to fish and seabirds, which mistake the plastic for food. Many of the plastics are covered with chemical pollutants.

Land Pollution
Many of the same pollutants that foul the water also harm the land. Mining sometimes leaves the soil contaminated with dangerous chemicals.

Pesticides and fertilizers from agricultural fields are blown by the wind. They can harm plants, animals, and sometimes people. Some fruits and vegetables absorb the pesticides that help them grow. When people consume the fruits and vegetables, the pesticides enter their bodies. Some pesticides can cause cancer and other diseases.

A pesticide called DDT (dichlorodiphenyltrichloroethane) was once commonly used to kill insects, especially mosquitoes. In many parts of the world, mosquitoes carry a disease called malaria, which kills a million people every year. Swiss chemist Paul Hermann Muller was awarded the Nobel Prize for his understanding of how DDT can control insects and other pests. DDT is responsible for reducing malaria in places such as Taiwan and Sri Lanka.

In 1962, American biologist Rachel Carson wrote a book called combat malaria.

Trash is another form of land pollution. Around the world, paper, cans, glass jars, plastic products, and junked cars and appliances mar the landscape. Litter makes it difficult for plants and other producers in the food web to create nutrients. Animals can die if they mistakenly eat plastic.

Garbage often contains dangerous pollutants such as oils, chemicals, and ink. These pollutants can leech into the soil and harm plants, animals, and people.

Inefficient garbage collection systems contribute to land pollution. Often, the garbage is picked up and brought to a dump, or landfill. Garbage is buried in landfills. Sometimes, communities produce so much garbage that their landfills are filling up. They are running out of places to dump their trash.

A massive landfill near Quezon City, Philippines, was the site of a land pollution tragedy in 2000. Hundreds of people lived on the slopes of the Quezon City landfill. These people made their living from recycling and selling items found in the landfill. However, the landfill was not secure. Heavy rains caused a trash landslide, killing 218 people.

Sometimes, landfills are not completely sealed off from the land around them. Pollutants from the landfill leak into the earth in which they are buried. Plants that grow in the earth may be contaminated, and the herbivores that eat the plants also become contaminated. So do the predators that consume the herbivores. This process, where a chemical builds up in each level of the food web, is called bioaccumulation.

Pollutants leaked from landfills also leak into local groundwater supplies. There, the aquatic food web (from microscopic algae to fish to predators such as sharks or eagles) can suffer from bioaccumulation of toxic chemicals.

Some communities do not have adequate garbage collection systems, and trash lines the side of roads. In other places, garbage washes up on beaches. Kamilo Beach, in the U.S. state of Hawai'i, is littered with plastic bags and bottles carried in by the tide. The trash is dangerous to ocean life and reduces economic activity in the area. Tourism is Hawai'i's largest industry. Polluted beaches discourage tourists from investing in the area's hotels, restaurants, and recreational activities.

Some cities incinerate, or burn, their garbage. Incinerating trash gets rid of it, but it can release dangerous heavy metals and chemicals into the air. So while trash incinerators can help with the problem of land pollution, they sometimes add to the problem of air pollution.

Reducing Pollution
Around the world, people and governments are making efforts to combat pollution. Recycling, for instance, is becoming more common. In recycling, trash is processed so its useful materials can be used again. Glass, Silent Spring, which discussed the dangers of DDT. She argued that it could contribute to cancer in humans. She also explained how it was destroying bird eggs, which caused the number of bald eagles, brown pelicans, and ospreys to drop. In 1972, the United States banned the use of DDT. Many other countries also banned it. But DDT didn't disappear entirely. Today, many governments support the use of DDT because it remains the most effective way to aluminum cans, and many types of plastic can be melted and reused. Paper can be broken down and turned into new paper.

Recycling reduces the amount of garbage that ends up in landfills, incinerators, and waterways. Austria and Switzerland have the highest recycling rates. These nations recycle between 50 and 60 percent of their garbage. The United States recycles about 30 percent of its garbage.

Governments can combat pollution by passing laws that limit the amount and types of chemicals factories and agribusinesses are allowed to use. The smoke from coal-burning power plants can be filtered. People and businesses that illegally dump pollutants into the land, water, and air can be fined for millions of dollars. Some government programs, such as the Superfund program in the United States, can force polluters to clean up the sites they polluted.

International agreements can also reduce pollution. The Kyoto Protocol, a United Nations agreement to limit the emission of greenhouse gases, has been signed by 191 countries. The United States, the world's second-largest producer of greenhouse gases, did not sign the agreement. Other countries, such as China, the world's largest producer of greenhouse gases, have not met their goals.

Still, many gains have been made. In 1969, the Cuyahoga River, in the U.S. state of Ohio, was so clogged with oil and trash that it caught on fire. The fire helped spur the Clean Water Act of 1972. This law limited what pollutants could be released into water and set standards for how clean water should be. Today, the Cuyahoga River is much cleaner. Fish have returned to regions of the river where they once could not survive.

But even as some rivers are becoming cleaner, others are becoming more polluted. As countries around the world become wealthier, some forms of pollution increase. Countries with growing economies usually need more power plants, which produce more pollutants.

Reducing pollution requires environmental, political, and economic leadership. Developed nations must work to reduce and recycle their materials, while developing nations must work to strengthen their economies without destroying the environment. Developed and developing countries must work together toward the common goal of protecting the environment for future use.

Fast Fact

How Long Does It Last?
Different materials decompose at different rates. How long does it take for these common types of trash to break down?

Fast Fact

Indoor Air Pollution
The air inside your house can be polluted. Air and carpet cleaners, insect sprays, and cigarettes are all sources of indoor air pollution.

Fast Fact

Light Pollution
Light pollution is the excess amount of light in the night sky. Light pollution, also called photopollution, is almost always found in urban areas. Light pollution can disrupt ecosystems by confusing the distinction between night and day. Nocturnal animals, those that are active at night, may venture out during the day, while diurnal animals, which are active during daylight hours, may remain active well into the night. Feeding and sleep patterns may be confused. Light pollution also indicates an excess use of energy.

The dark-sky movement is a campaign by people to reduce light pollution. This would reduce energy use, allow ecosystems to function more normally, and allow scientists and stargazers to observe the atmosphere.

Fast Fact

Noise Pollution
Noise pollution is the constant presence of loud, disruptive noises in an area. Usually, noise pollution is caused by construction or nearby transportation facilities, such as airports.

Noise pollution is unpleasant, and can be dangerous. Some songbirds, such as robins, are unable to communicate or find food in the presence of heavy noise pollution. The sound waves produced by some noise pollutants can disrupt the sonar used by marine animals to communicate or locate food.

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Illustrators

Mary Crooks, National Geographic Society

Editors

Jeannie Evers, Emdash Editing, Emdash Editing

Producer

National Geographic Society

other

Last Updated

October 19, 2023

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Pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants.

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The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.

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Shifting Baselines? The Ecological Implications of Simultaneous Eutrophication and Overfishing | Research Project Database | Grantee Research Project | ORD | US EPA

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EPA Grant Number: FP917087 Title: Shifting Baselines? The Ecological Implications of Simultaneous Eutrophication and Overfishing Investigators: Allgeier, Jacob Edward Institution: University of Georgia EPA Project Officer: Packard, Benjamin H Project Period: August 1, 2010 through July 31, 2013 Project Amount: $111,000 RFA: STAR Graduate Fellowships (2010) RFA Text | Recipients Lists Research Category: Academic Fellowships , Fellowship - Ecosystem Services: Aquatic Systems Ecology

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Sea Level Rise Viewer: Visualize community-level impacts from coastal flooding or sea level rise (up to 10 feet above average high tides) at U.S. coastal locations.

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Human activity is causing the concentration of atmospheric carbon dioxide to increase. In addition to its role as a greenhouse gas, carbon dioxide reacts with water to form a weak acid called carbonic acid, which lowers the pH of seawater.

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Science and Global Issues: Biology - Ecology: Living on Earth, Activity 14

= 2000 tuna

Stage One

In this stage you will examine how birth rate, death rate, and migration rate affect the sustainability of the Avril Gulf tuna population. The instructions on your Student Sheet will help to guide you.

Start stage 1 >>

Stage Two

In this stage you will examine how
predators, amount of food, and incidents
of disease and pollution affect the
sustainability of the Avril Gulf tuna
population. Continue to refer to your
Student Sheet for specific instructions.

Start stage 2 >>

Stage Three

In this stage you will examine how
fishing intensity and length of fishing
season affect the sustainability of the
Avril Gulf tuna population. Continue to
refer to your Student Sheet for specific
instructions.

Start stage 3 >>

Stage Four

In this stage all of the variables can be
manipulated to determine their collective
affect on the sustainibility of the Avril Gulf
tuna population. Continue to refer to
your Student Sheet for specific
insructions.

Start stage 4 >>

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Science and Global Issues: Biology - Ecology: Living on Earth, Activity 14 = 2000 tuna In this stage you will examine how birth rate, death rate, and migration rate affect the sustainability of the Avril Gulf tuna population. The instructions on your Student Sheet will help to guide you.

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Join an activity with your class and find or create your own quizzes and flashcards.

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Join a game of kahoot here. Kahoot! is a free game-based learning platform that makes it fun to learn – any subject, in any language, on any device, for all ages!

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Welcome to the Virtual Earth System Laboratory! Here, the Ice Sheet System Model (ISSM) team hosts simulations related to glaciers, ice sheets, sea level and solid earth.

Our earth science simulations fall into one or more categories, which can be reached via the links below.

Glaciers
Simulations of Glacier Flow and Sensitivity to Climate
Model the evolution of glaciers in Alaska, Patagonia and the Himalayan regions in response to variations in surface temperature, snow precipitation, and other factors related to climate change.

Ice Sheets
Simulations of Ice Sheet Flow and Sensitivity to Climate and Forcings
Model the evolution of ice sheets such as Greenland and Antarctica, and understand the factors that control their evolution and contribution to sea level rise in the coming decades/centuries. This includes basal friction at the ice/bed interface, snow precipitation, temperature, etc.

Sea Level
Simulations of Sea Level Rise and Contribution from the Cryosphere
Model the evolution of sea level over the entire Earth, and understand the contribution of glaciers and polar ice caps to its rise or decline in a changing climate.

Solid Earth
Simulations of Processes Undergone by the Earth's Lithosphere and Mantle
Here you will find simulations related to the Earth' interior. This includes models of geothermal heat flux and their impact on the thermal profile of polar ice sheets, models of mantle plumes under the ice, models of Glacio-Isostatic Rebound, and other models related to processes undergone by the earth lithosphere and mantle.

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Visit NASA's portal for an in-depth look at the science behind sea level change.