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https://catalogue.ceh.ac.uk/documents/0c17a041-8852-4800-9c04-2ab2dd858837

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Share information about the soil in your area with other users and help us to improve our soil map of the UK.

Let's put citizen science into action and build up a community soils dataset produced by you - the users.

All information submitted is anonymous and will be published within this application under the Open Government License.

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Share information about the soil in your area with other users and help us to improve our soil map of the UK. Let's put citizen science into action and build up a community soils dataset produced by you - the users. All information submitted is anonymous and will be published within this application under the Open Government License.

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Episode 5: Global Warming, It's All About Carbon | Krulwich Wonders | NPR

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Episode 5: Global Warming, It's All About Carbon | Krulwich Wonders | NPR

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The Global Carbon Project (GCP) was established in 2001 in recognition of the enormous scientific challenge and fundamentally critical nature of the issue for Earth sustainability.

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A new film shows how restoring Wales' extensive peat bogs can help benefit wildlife and improve the quality of our environment by reducing flood risk and helping fight climate change by locking up atmospheric carbon.

The film that has been produced and filmed by RSPB Cymru, shows that if peatlands are restored, farmers will lose fewer sheep, which can become trapped in drainage ditches.

Many people see peat bogs as soggy barren places where you get stuck and lose your wellington boot, or where archaeologists dig up the occasional perfectly-preserved four-thousand-year old body!
Watch: Resilient Ecosystem Fund (REF) Peatland Restoration Project Film (English)
The closest many of us will get to a peat bog is picking up the bagged up stuff at our local garden centre to pot plants (this is not recommended because there are plenty of ecologically friendly peat free compost alternatives).

But peat bogs have been getting a rather lot of publicity lately.

A peat bog over six times the size of Wales has been discovered in the Congo in Africa.

And in recognition of the value of Welsh peat bogs, Alun Davies AM recently announced the Welsh Government's ambitious plan to bring all Welsh peatlands into restoration management within seven years.

Wales has a lot of peat bog; an estimated 70,000 hectares of upland blanket bog scattered all the way from Snowdonia to Pembrokeshire and the South Wales Valleys. However, much of this is not in its pristine natural wet condition due to historic drainage and burning aimed at improving land for agriculture and post-war afforestation.
Gwylio: Prosiect Gronfa Ecosystem Wydn. Film adfer mawndir (Cymraeg)
So what exactly is peat and why is it suddenly 'the coolest thing in town?'

Well, peat is waterlogged soil, made up partially decomposed vegetation, mostly sphagnum moss.

Over thousands of years that vegetation has been growing and compacting at a rate of a miniscule 0.5 to 1mm a year. It doesn't sound like much but over millennia, many Welsh peat bogs have become four to six metres deep, some even more.

As the bog grows and the moss partially decomposes to form peat, it draws in that all important climate change gas - carbon dioxide - and stores it as carbon within the peat. And it's incredibly efficient at doing that.

Here are some mind-blowing stats that you may not be aware of.

Although peatlands only cover around 3% of the world's surface they contain more carbon than all of the world's rainforests.

Peatlands are the UK's single-most important terrestrial carbon store, containing 20 times more carbon than all UK forests.

In Wales, nine times more carbon is stored in peat than in all vegetation. And although Britain is a very small island, it does in fact contain an amazing 13% of the world's upland blanket bog.

So just like cutting down rainforests releases carbon dioxide into the atmosphere, draining and drying out peat bogs does the same.

It is estimated that those drained and damaged peat bogs in the UK currently pump out 3.7m tonnes of carbon dioxide a year; that's equivalent to the average emissions of 660,000 households (that's all the houses of Edinburgh, Cardiff and Leeds combined).

However - and this is the true value and potential of peatlands - unlike rainforests that take decades to restore, damaged peatlands can be returned through filling in drainage ditches with a digger to become functioning peat bogs that draw in carbon in matter of years.

Indeed, on average, healthy peat bogs remove between 30 to 70 tonnes of carbon per square kilometre from the atmosphere annually. And not only that, making damaged bogs healthy again is relatively cheap.

An experienced digger operator can put in a dam in quite a short space of time and you can quite quickly re-wet a hectare of peat bog.

So there is no doubt that restoring peatlands presents a massive opportunity to both the Welsh and UK Governments in helping to meet their binding targets of reducing carbon emissions by 40% and 34% respectively, from their 1990 level by 2020.

However, this is not the only benefit of peatland restoration.

For example, 70% of our drinking water in the UK comes from upland areas and it is vital that peat bogs are in good condition, so that the water we drink is good quality and costs are kept low for customers.

Appropriately managed, restoring peat bogs can also provide habitat for some of Wales' most endangered species like the curlew and the golden plover, which were once common in Wales but have seen a massive decrease in recent decades.

The golden plover has seen more than an 80% reduction in its numbers in recent decades in many areas. Furthermore, there is increasing evidence that retaining water in upland areas will reduce flooding in lowland valleys. One of the most important elements to consider when restoring peatland is the people who live and work in these upland areas.

The vast majority of Welsh uplands are farmed in some way and although some farmers are yet to be convinced that peatlands restoration will directly benefit their businesses, some farmers like Glyn Roberts, who farms in the Migneint area of North Wales, believes that the farming community should support the work for wider environmental reasons.

He said: "We as an industry have an obligation to do everything that we can to mitigate as much as we can against global warming and in this context, I think it's a good thing".

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Restoring ancient peat bogs is vital to trap harmful carbon

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A new film shows how restoring Wales' extensive peat bogs can help benefit wildlife and improve the quality of our environment by reducing flood risk and helping fight climate change by locking up atmospheric carbon. The film that has been produced and filmed by RSPB Cymru, shows that if peatlands are restored, farmers will lose fewer sheep, which can become trapped in drainage ditches.

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Carbon Neutral Cities Alliance - Urban Sustainability Directors Network

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Home Page - The Carbon Underground - Reversing Climate Change

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Reverse climate change and create secure food production through regenerative farming, agriculture, ranching and livestock technologies

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Migneint-Arenig-Dduallt - Special Area of Conservation - SAC - Habitats Directive

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SAC selection criteria for site Migneint-Arenig-Dduallt, EU Code UK0030205, Unitary Authority West Wales and The Valleys, Wales. The Habitats Directive: selection of Special Areas of Conservation in the UK, second edition, JNCC (2002). This information replaces JNCC Report 270.

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international union for the conservation of nature

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Peatland Gateway | Peatland Programme of IUCN UK

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Discover peatland restoration case studies here in the UK and around the world, as well as links to other organisations and initiatives.

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The carbon cycle underlies all Earth systems-both natural and human-managed. That includes urban areas, which account for 60-80% of energy consumption and carbon emissions worldwide.

Typically, natural science studies of carbon in cities have focused on quantifying input and output, without examining how these carbon fluxes are tied to complex economic, behavioral, and political factors. Likewise, social science studies have not considered urban carbon on scales of time and space that connect with approaches used in the natural sciences.

As a first step in building an interdisciplinary community to explore human-carbon interactions in cities, USGCRP's Carbon Cycle Interagency Working Group-via the U.S. Carbon Cycle Science Program-sponsored a workshop last year with natural and social scientists and engineers from within and outside the government. The workshop participants delved into the challenges and opportunities involved in building a holistic research program on urbanization and the carbon cycle. They produced four peer-reviewed reports and a white paper to share their insights with the broader scientific community and with the research funding entities that catalyze advancements in carbon cycle science. "These community-led products are already serving as valuable input for evolving interagency conversations," said Gyami Shrestha, Director of the U.S. Carbon Cycle Science Program Office.

Recently, these reports were published in a special section of the open-access journal Earth's Future. The reports synthesize contributions from the social sciences ( Marcotullio et al.), engineering sciences and technology ( Chester et al.), and the natural sciences ( Hutyra et al.), and present a new framework for the study of the urban carbon cycle that integrates perspectives from multiple disciplines ( Romero-Lankao et al.).

These publications lay the groundwork for research that not only has the potential to advance understanding of the carbon cycle and urban environments, but also to inform the climate-resilient development and management of urban green spaces and infrastructure.

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New Research Frontiers: the Urban Carbon Cycle

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The carbon cycle underlies all Earth systems-both natural and human-managed. That includes urban areas, which account for 60-80% of energy consumption and carbon emissions worldwide. Typically, natural science studies of carbon in cities have focused on quantifying input and output, without examining how these carbon fluxes are tied to complex economic, behavioral, and political factors.

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Source: Halfdan Carstens

Part One of a two part series by author Rasoul Sorkhabi, focussing on oil and gas in the Middle East. Part Two - How Much Oil in the Middle East?

The term 'Middle East' is not without problems. First, it has colonial connotations, as the phrase first appeared in the mid-nineteenth century as part of the Europe-centred division of the East into the Near, Middle and Far East. Second, there is no consensus on the geographical extent of the Middle East. Some define it as the region between India and Egypt, in which case it has been aptly designated by the United Nations as Western Asia. Other definitions also add North Africa or central Asia.

For the purpose of this article, the term 'Middle East' focuses on the oil-rich countries in south-west Asia including Iran, Iraq, Syria, Kuwait, Saudi Arabia, Bahrain, Qatar, United Arab Emirates (UAE), Oman, and Yemen. These ten countries together have an area of 5.1 million square kilometres, or about 3.4% of the Earth's land surface, but they possess according to BP's 2012 Statistical Review of World Energy, 48% of world's known oil reserves and 38% of natural gas reserves.

From time to time, regions such as the Caspian or West Africa have been fantasised as 'another Middle East' but none has materialised, which begs this important question: why is there so much oil in the Middle East? This article synthesises our knowledge about this question and briefly describes the geological factors for the abundance of oil in the Middle East.

Gondwana Margin and Tethys

The Proterozoic-Cambrian transition at about 542 Ma opened a new chapter in the geologic history of the Middle East with far-reaching implications for petroleum resources of this region. After a long history of ocean subduction and micro-continental collision along the north-eastern margin of Africa from about 700 Ma to 600 Ma, the basement rock of the Middle East (the Nubian-Arabian shield) was consolidated. This event, together with some other collisions, assembled the supercontinent of Gondwana in the southern hemisphere, comprising Africa, India, Australia, Antarctica, and South America. At this time the Middle East was positioned on the north-facing passive margin of Gondwana. Throughout Paleozoic and Mesozoic times, the Middle East was a locus of sedimentation over a long and wide shelf affected, from time to time, by sea level changes. As Gondwana consolidated at the turn of the Cambrian, microorganisms and marine species also rapidly evolved and diversified, thus enriching marine sediments with organic carbon necessary for hydrocarbon generation.

The Tethys Ocean, which washed the northern margin of Gondwana, was not a single ocean, but developed in at least three oceanic basins: Proto-Tethys (Infracambrian-Carboniferous), Paleo-Tethys (Ordovician-Jurassic), and Neo-Tethys (Permian-Paleocene). This sequential development of Tethys took place as continental fragments successively broke away from the Gondwana margin and drifted northward to join the paleo-Asian continent. The opening of each Tethys ocean was accompanied by extensional tectonics which, in turn, created continental rifts during the Infracambrian (Ediacaran-Cambrian transition period), the Ordovician, and the Permian in the Middle East. These rift basins added favourable sites for petroleum generation in the region.

At the end of the Palaeozoic, Gondwana merged with Laurasia to form the largest supercontinent ever, Pangea. It was also during this time that Proto-Tethys closed and Neo-Tethys began opening. In the Late Cretaceous, Neo-Tethys began to subduct beneath the southern margin of paleo-Asia (along the Anatolia-Iran-Tibet margin) and shrank in size until the ocean completely disappeared in the Eocene and gave way to a foreland basin in front of the rising Bitlis-Zagros-Himalayan mountains.

The Phanerozoic sedimentary succession in the Middle East is up to 12,000m thick and can be divided into three mega-sequences:

1. The Infracambrian-Carboniferous sequence, consisting largely of siliciclastic rocks and showing long gaps in sedimentation (during the middle-Paleozoic lower sea levels);

2. the Permian-Cretaceous sequence, made up of mainly carbonate rocks with only brief hiatuses; and

3. the Cenozoic foreland sequence including both carbonates and siliciclasitcs (toward the top) and with early Paleocene and Oligocene hiatuses in some areas.

This tectonic-sedimentation framework impacted on petroleum generation and accumulation in the Middle East in ways unique to this region.

Back to the Sources

Organic-rich source rocks (with total organic carbon >5%) are not unique to the Middle East. What is remarkable about the Middle East's source rocks, though, is that they were deposited on a passive continental-shelf margin spanning Palaeozoic and Mesozoic times in relatively stable conditions, which took advantage of sea-level rises, anoxic (reducing) environments, and nutrient-rich upwelling sites off the coasts. Moreover, these marine shales and marls contained oil-prone kerogen types I (protein/lipid-rich algal organic matter) and II (lipid-rich but with lower hydrogen-to-carbon ratios).

One of the lucky horizons for petroleum generation in the Middle East is the Silurian 'hot' shale, called the Qusaibah Shale in Saudi Arabia but also found in some other parts of the Middle East and North Africa. Paleogeographic modeling of Paleozoic continents and atmospheric circulations (Judith Parrish, AAPG Bulletin, June 1982) shows that during the Silurian the Middle East was close to a major upwelling current that enriched the sediments with exceptional amounts of organic matter.

However, over 70% of the Middle East oil was generated from Jurassic-Cretaceous sediments (accounting for less than 30% of the Phanerozoic eon). Some of these classic source rocks include the Sargelu Formation (Middle Jurassic, 150-200m thick in type locality), Garau Formation (Lower Cretaceous, over 800m thick), Gadvan Formation (Lower Cretaceous, 100m thick), and Kazhdomi Formation (Middle Cretaceous, 200m thick) in the Zagros Basin of south-west Iran, and age-equivalent limey-shale formations in Iraq and the Persian Gulf areas.

To explain these rich source rocks we need to consider the position and extent of the Neo-Tethys shelf during Jurassic and Cretaceous times. Neo-Tethys was then located close to the warm, organic-rich Equator; it possessed a broad 2,000-3,000 km-wide shelf and a length of at least twice that (Murris, AAPG Bulletin, May 1980). Moreover, Neo-Tethys was triangular in shape, pointed (thinning) toward the west; it was thus a partly enclosed basin with its wide shelf oriented almost west-east, and in a favorable position to benefit from organic-rich sedimentation processes and high stand sea-levels.

In Late Jurassic-Early Cretaceous times, Gondwana was split apart, and as rift volcanism and sea-floor spreading developed, ocean temperatures rose and ocean waters were enriched with nutrient elements from volcanic outpourings (along mid-ocean ridges and continental margins or island arcs). Oxygen-isotope analyses of marine limestones have shown that 125-85 Ma was a time of severe global warming due to a rapid increase in atmospheric carbon dioxide concentrations (mainly from increased volcanic activities). This is consistent with sequence stratigraphic evidence for sea-level maxima in mid-late Cretaceous times. Warm climate, high-stand seas and increases in the nitrogen-phosphorus-carbon contents of oceans, in turn, led to a profuse radiation of plankton populations - a key factor in the organic richness of marine sediments laid down during that period. Neo-Tethys most benefited from these events and the Middle East was in the right position at the right time.

Based on their sedimentary facies distributions, R. J. Murris has divided the Mesozoic carbonates of the Middle East into two categories. The first one is carbonate ramps (mixed with clastic clayey beds), with cycles ('layer cakes') ranging in thickness from 30 to 100m and deposited during marine regressions when clastics were brought into the basin. The second category is differentiated carbonate shelf or platform carbonates, which were deposited under transgressive conditions, where differentiation is marked with starved (sediment-deficient) euxinic basins separated by high-energy margins from carbonate-evaporite platforms. Rich source rocks are included in the second category.

Into the Storage and Trap

The Middle East is renowned for its rich carbonate oil reservoirs. Such reservoir rocks are also found in North America and Western Siberia (mainly Palaeozoic), Central and South America (mainly Mesozoic), and South East Asia (mainly Miocene). In the Middle East, however, carbonates were deposited on a long and wide shelf from the Permian to the Paleocene with insignificant hiatus. Even after the Arabia-Asia collision, carbonate sedimentation continued in a very shallow marine environment (an ongoing process in the Persian Gulf). Indeed, large oil fields in the Middle East have thick stacks of multiple carbonate payzones.

Limestone and dolomite reservoirs of the Middle East have fairly good porosity and permeability. Primary porosity has been well preserved in packstones and grainstones such as those of the Late Jurassic Arab Formation widely spread in the Middle East. In Saudi Arabia's Ghawar field (the world's largest oil field), two producing members (C and D) of the Arab Formation, have thicknesses of 30m and 80m respectively, and a porosity of 20%. The same formation in the UAE ranges from 130 to 240m in thickness and 10-30% in porosity. Moreover, the Zagros deformation has created fracture networks enhancing permeability, especially in cemented limestones such as the Oligocene-Miocene limestones of south-west Iran (Asmari Formation) and eastern Iraq (Jerribe Formation), where their thicknesses range from 120-480m, and porosities from 8-24%.

Apart from marine shale and marl cap rocks, many Middle East basins also contain evaporite beds, which are efficient seals because of their ductility. The main evaporite horizons include:

1. the Infracambrian Hormuz salt;

2. Triassic interbedded evaporites;

3. Late Jurassic Gotnia-Hith Formation; and

4. and the Miocene Gachsaran Formation. In this manner, the entire Phanerozoic succession is bounded by evaporite seals both at the bottom and on the top.

These ductile evaporite and shale beds have also acted as detachment horizons for the Zagros thrust structures, thus producing vertical compartments of petroleum systems within the sedimentary succession.

Reservoir Rocks

Zagros Deformation and Salt Domes

Basin modeling of various fields of the Middle East has shown that the Jurassic-Cretaceous source rocks were buried to oil-generation temperatures during the Neogene, and that the oil window partly overlapped in time with Zagros deformation and the development of large anticlines as structural traps.

Three important features of Zagros deformation helped to preserve oil accumulations in the Middle East. Firstly, the Cenozoic Zagros foreland basin was superimposed on the Paleozoic-Mesozoic Tethyan sediments, providing an overburden necessary for preservation as well as burial heating of the underlying source rocks. Secondly, the relatively slow motion of the African-Arabian plate during the Cenozoic prevented a wide-spread, severe tectonic deformation, unlike what occurred in other parts of the Tethyan belt, most notably in the Himalayas. (The Indian plate has moved at a rate of 5-6 cm per year after the India-Asia collision at 50 Ma, which is about three times faster than that of the African-Arabian plate over the same period.) Thirdly, the presence of ductile Hormuz salt at the base of the Phanerozoic sediments helped to detach the sedimentary cover from the underlying igneous-metamorphic basement rock. Therefore, Zagros deformation evolved as a thin-skinned tectonic deformation in which the basement rock did not override the sedimentary cover nor did it exhume the entire Tethyan shelf sediments. (Such diastrophism has happened in the thick-skinned tectonic deformation and uplift of the Himalayas.)

In fact, in the Zagros Mountains Precambrian metamorphic rocks do not outcrop, and those metamorphic schists and granites in Zagros which were once thought to be of Precambrian age, have been dated as Paleozoic by high-resolution radiometric methods. Note that a thin-skinned deformation in the Zagros fold-and-thrust does not overrule the possibility of basement deformation at deeper levels; it simply means that deformation of the sedimentary cover has been decoupled from that of the basement (of which we have little knowledge). Perhaps, millions of years in the future, Zagros will also look much like today's Himalayas, especially if the motion of the Arabian Plate, currently being pushed by the Red Sea rifting, becomes faster as the Red Sea develops into a wide ocean.

The Infracambrian Hormuz salt has also created salt diapris and folds, which provide favorable structural traps for oil; these salt movements date back to the Late Cretaceous. Although the Hormuz salt has been mapped only in some areas of the Middle East, its true extent is not precisely known as it has not been drilled in areas such as southern Iraq or the UAE.

Why So Much Oil?

For petroleum to be successfully generated, migrated, accumulated, and preserved, all elements and processes of the petroleum system, including organically rich and thermally matured source rocks, porous-permeable reservoir rocks, effective extensive cap rocks, and appropriate time relations between oil migration and trap formation should be present. Obviously, the Middle East qualifies all these conditions to a high degree and quality.

Since our discussion is at the regional scale of the Middle East, we have to simplify the issue and thus ignore variations in structural and sedimentation histories within the region. One such variation, for example, is that as we move away from the Precambrian outcrops in western Saudi Arabia toward the High Zagros in south-west Iran, the basin(s) become deeper and Mesozoic-Cenozoic sediments attain enormous thicknesses. Few wells have, indeed, penetrated the Paleozoic sections in these deeper parts of the basin. Moreover, some parts of the Middle East, notably central and northern Iran, virtually remain unexplored. While keeping these shortcomings in mind, several key points may be highlighted to explain the abundance of oil in the Middle East:

1. A 500-million history of sedimentation on the passive continental margin of Gondwana;

2. Sedimentation occurred largely within latitudes 30° North-30° South, where the climate is warm and organic activity is at high levels;

3. The wide, long (east-west oriented) shelf of Neo-Tethys during the Jurassic-Cretaceous;

4. The favourable position of the Middle East during the mid-Cretaceous global warming, coupled with sea level rise, and plankton abundance;

5. Marine source rocks containing oil-prone kerogen types;

6. The proximity of interbedded source rocks to reservoirs minimised oil migration pathways;

7. An enormous thickness of sediments (predominantly carbonates but some clastics as well) provided the necessary storage for the huge amounts of generated oil;

8. The presence of effective regional seals, both marine shales and evaporites, at the bottom, on the top, and within the sedimentary package;

9. Superimposition of the Cenozoic Zagros foreland basin above the Tethyan shelf sediments;

10. Relatively slow motion of the Arabian plate and the presence of ductile evaporite-shale layers at the base of the Phanerozoic sediments resulted in a thin-skinned tectonic regime in which the Precambrian igneous-metamorphic basement did not override or exhume the entire Tethyan shelf sediments;

11. Large 'whaleback' anticlines generated by the 'gentle' Zagros compression (folding and thrusting) or salt diapirs provided abundant structural traps for oil accumulations.

Since the 1950s a number of petroleum geologists working in the Middle East have opined on the richness of oil in that region; classic papers published in the AAPG Bulletin include Baker and Henson (October 1952); Law (January 1957); Kamen-Kaye (December 1970); Murris (May 1980); Bois et al. (September 1982); and Klemme & Ulmishek (December 1991). The Late Z. R. Beydoun also discussed an issue in Episodes, June 1998.

Habitat of Oil, edited by Lewis Weeks (1958) is the proceedings volume of an AAPG symposium on this topic, which also includes several classic papers relevant to the Middle East. I have benefited from all these sources.

For information on the geology of specific basins and chronostratigraphic events in the Middle East, I have found review papers in GeoArabia as well as the following volumes particularly helpful and handy:

Alsharhan, A.S., and Nairn, A.E.M. (2003) Sedimentary Basins and Petroleum Geology of the Middle East (Amsterdam: Elsevier)

Beydoun, Z.R. (1991) Arabian Plate Hydrocarbon Geology and Potential: A Plate Tectonic Approach (AAPG Studies in Geology #33, Tulsa)

Sharland, P.R. et al. (2001) Arabian Plate Sequence Stratigraphy (GeoArabia Special Publication 2, Bahrain)

About this article.

This article is the first in a pair of articles by Rasoul Sorkhabi relating to oil and gas in the Middle East. If you have enjoyed reading this article make sure you read the follow-up piece:

How Much Oil in the Middle East?

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In terms of oil reserves, the Middle East is second to none. This "oil miracle" of the world has been shaped by a set of favorable factors, some global and others local, inscribed in the geologic history of the region.

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Reuters/Andy Clark

Carbon has a bad name. The 2015 Paris climate agreement calls for a balance between carbon dioxide emissions to the atmosphere and to earthbound carbon sinks. Climate Neutral Now, a United Nations initiative, encourages businesses and individuals to voluntarily measure, reduce and offset their greenhouse-gas emissions by 2050. The American Institute of Architects has challenged the architecture community worldwide to become carbon neutral by 2030. The Carbon Neutral Cities Alliance, an international network of urban-sustainability directors, aims to slash its cities' greenhouse-gas emissions by 80% by 2050.

'Low carbon', 'zero carbon', 'decarbonization', 'negative carbon', 'neutral carbon', even 'a war on carbon' - all are part of the discourse. If we can reduce our carbon emissions, and shrink our carbon footprint, the thinking goes, we can bring down the carbon enemy. It's no wonder that businesses, institutions and policymakers struggle to respond.

But carbon - the element - is not the enemy. Climate change is the result of breakdowns in the carbon cycle caused by us: it is a design failure. Anthropogenic greenhouse gases in the atmosphere make airborne carbon a material in the wrong place, at the wrong dose and for the wrong duration. It is we who have made carbon toxic - like lead in our drinking water or nitrates in our rivers. In the right place, carbon is a resource and a tool.

Carbon dioxide is the currency of photosynthesis, a source of Earth's capacity for regeneration. Soil carbon is the guarantor of healthy ecosystems and food and water security. Carbon atoms are the building blocks of life. Wool, cotton and silk are carbon compounds, as are many industrial polymers and pure 'supercarbons' such as diamonds and graphene.

After 30 years of designing sustainable buildings and landscapes that manage carbon, I believe it is time to breathe new life into the carbon conversation. Rather than declare war on carbon emissions, we can work with carbon in all its forms. To enable a new relationship with carbon, I propose a new language - living, durable and fugitive - to define ways in which carbon can be used safely, productively and profitably. Aspirational and clear, it signals positive intentions, enjoining us to do more good rather than simply be less bad.

Words drive actions

It is easy to lose one's way in the climate conversation. Few of the terms are clearly defined or understood. Take 'carbon neutral'. The European Union considers electricity generated by burning wood as carbon neutral - as if it releases no CO ₂ at all. Their carbon neutrality relies problematically on the growth and replacement of forests that will demand decades to centuries of committed management. Another strategy is to offset fossil-fuel use by renewable-energy credits - this still means an increase in the global concentration of atmospheric CO ₂.

Even more confusing is the term 'carbon negative'. This is sometimes used to refer to the removal of CO ₂ from the atmosphere. For example, Bhutan's prime minister has indicated that his country is carbon negative, because its existing forests sequester more CO ₂ than the country emits and Bhutan exports hydroelectric power (see go.nature.com/2es9lgt). But aren't trees having a positive effect on atmospheric carbon, and hydroelectric power a neutral one?

Sander van der Torren Fotografie

Carbon sequestration is a long-sought goal. It requires two elements: a way to capture carbon from the atmosphere or a chimney and a way to store it safely and permanently. But some so-called carbon-storage methods are paradoxical. For example, in enhanced oil recovery, CO ₂ is injected into rock formations to flush out remnant crude oil, which is eventually burned.

At the same time, enterprises are starting to announce their hopes to be 'carbon positive' by, for example, producing more renewable energy than their operations require, or by sequestering carbon through planting trees.

Such terms highlight a confusion about the qualities and value of CO ₂. In the United States, the gas is classified as a commodity by the Bureau of Land Management, a pollutant by the Environmental Protection Agency and as a financial instrument by the Chicago Climate Exchange.

A new language of carbon recognizes the material and quality of carbon so that we can imagine and implement new ways forward (see ' The new language of carbon '). It identifies three categories of carbon - living, durable and fugitive - and a characteristic of a subset of the three, called working carbon. It also identifies three strategies related to carbon management and climate change - carbon positive, carbon neutral and carbon negative.

Source: McDonough Innovation

Start with the soil

How do we work with the carbon cycle to preserve and enhance the benefits it naturally provides? From the soil up.

Carbon is at the heart of soil health. In healthy ecosystems, when plants convert CO ₂ into carbon-based sugars - liquid carbon - some flows to shoots, leaves and flowers. The rest nourishes the soil food web, flowing from the roots of plants to communities of soil microbes. In exchange, the microbes share minerals and micronutrients that are essential to plants' health. Drawn into the leaves of plants, micronutrients increase the rate of photosynthesis, driving new growth, which yields more liquid carbon for the microbes and more micronutrients for the fungi and the plants. Below ground, liquid carbon moves through the food web, where it is transformed into soil carbon - rich, stable and life-giving. This organic matter also gives soil a sponge-like structure, which improves its fertility and its ability to hold and filter water.

This is how a healthy carbon cycle supports life. This flow kept carbon in the right place in the right concentration, tempered the global climate, fuelled growth and nourished the evolution of human societies for 10,000 years.

Many soil researchers believe it could do so again. Ecologist and soil scientist Christine Jones, founder of the Amazing Carbon Project, describes the "photosynthetic bridge" between atmospheric carbon and liquid carbon, and the "microbial bridge" between plants and biologically active, carbon-rich soils as twin cornerstones of landscape health and climate restoration.

David Johnson at the New Mexico State University Institute for Energy and the Environment in Las Cruces has studied the carbon-microbial bridge. He found that the most important factor for promoting plant growth and cultivating soil carbon was not added nitrogen or phosphorus but the carbon inputs from other plants.

Design for living

Let's keep those carbon bridges open on all landscapes - rural and urban. Let's use carbon from the atmosphere to fuel biological processes, build soil carbon and reverse climate change. Let's adopt regenerative farming and urban-design practices to increase photosynthetic capacity, enhance biological activity, build urban food systems, and cultivate closed loops of carbon nutrients. Let's turn sewage-treatment plants into fertilizer factories. Let's recognize carbon as an asset and the life-giving carbon cycle as a model for human designs.

"To enable a new relationship with carbon, I propose a new language."

All designs - from products to buildings, cities and farms - could be carbon positive. This may take a century, but that's how long it took us to get into our current carbon calamity. The sooner we start, the better. By 2030, our exuberantly urbanizing planet is expected to convert more habitat and farmland into cities than all previous urban growth combined. More than 2 billion urbanites will live in homes, attend schools and work in factories that are not yet built. Despite these challenges, there are models of hope.

In 1989 my architecture firm designed a day-care facility in Frankfurt, Germany, based on 'a building like a tree' that could be operated by children, who would move solar shutters, open and close windows, grow food on roof terraces and irrigate the gardens with rainwater.

The idea of 'buildings like trees' and 'cities like forests' endured, and we started to approach our product, building and city designs as photosynthetic and biologically active, accruing solar energy, cycling nutrients, releasing oxygen, fixing nitrogen, purifying water, providing diverse habitats, building soil and changing with the seasons.

The Adam Joseph Lewis Center for Environmental Studies at Oberlin College in Ohio, which we designed, is a built example of this philosophy. It purifies its waste water and sewage in an on-site system that produces carbon-rich organic compost. This year the project is producing solar energy at an annual rate of 40% more than it needs. The building still relies on the electrical grid when solar energy is unavailable. Soon, with new and affordable on-site thermal and electric battery storage systems, buildings like this can be both carbon and energy positive.

In the Netherlands, Park 20|20 near Amsterdam applies these carbon-positive design strategies at the campus scale. Next door, the Valley at Schiphol Trade Park, the country's national hub for the circular economy, will scale these and many other innovations to create an urban ecology of work, supply chains and collaborative spaces. The development will be a network of integrated buildings, landscapes and technical systems operating as a connected whole. Each building is oriented to the path of the Sun to maximize exposure during winter and shade during summer. Photovoltaic arrays and green roofs are the system's leaves and roots, harvesting renewable energy, absorbing and filtering water, producing food and providing habitat for other living things in a vibrant, sustainable business community.

The energy sector, too, can be generously carbon positive. SunPower, based in San Jose, California, and other solar providers are developing 'solar orchards' - power plants that perform as working farms. Rotating arrays of elevated solar panels shade the earth and provide habitat for grassland, which captures water, nitrogen and carbon to build soil health, can include legumes to fix nitrogen, and can provide food for grazing animals, in turn providing protein and wool. By design, the power plant generates an abundance of benefits: renewable energy, biodiversity, food, soil restoration, nutrient cycling, carbon sequestration, water conservation, fibre products, and agricultural and manufacturing jobs. Thus working durable carbon creates and supports living carbon while reducing fugitive carbon, all in an economically robust and profitable model.

Such designs offer an inspiring model for climate action. It all starts with changing the way we talk about carbon. Our goal is simple and positive: a delightfully diverse, safe, healthy and just world - with clean air, soil, water and energy - economically, equitably, ecologically and elegantly enjoyed.

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Reuters/Andy Clark Carbon has a bad name. The 2015 Paris climate agreement calls for a balance between carbon dioxide emissions to the atmosphere and to earthbound carbon sinks. Climate Neutral Now, a United Nations initiative, encourages businesses and individuals to voluntarily measure, reduce and offset their greenhouse-gas emissions by 2050.

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Berwyn & Migneint Special Areas of Conservation in Wales - The RSPB

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Restoring active blanket bog in Berwyn and Migneint Special Areas of Conservation: Under the EU Habitats Directive, blanket bog is a priority habitat. Read more

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The official website of the Snowdonia National Park Authority

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This interactive map is unfortunately not available on your device, because HTML5 Video, WebGL or support for large video textures are not available. Please use a recent version of Firefox or Google Chrome, or see the original version of the carbon dioxide map at the NASA Goddard Space Flight Center website.

This interactive map is currently not available for Internet Explorer. Please use a recent version of Firefox or Google Chrome, or see the original version of the carbon dioxide map at the NASA Goddard Space Flight Center website.

Click the play button to start.

To navigate in time, click on the circle on the left.

To adjust the center of the map, click and drag on the map.

To zoom in and out, use the scroll wheel or the slider on the right.

To navigate in time, tap on the circle on the left.

To zoom in and out, tap the slider on the right.

To navigate in time, click on the circle on the left. To adjust the center of the map, click and drag on the map.
To zoom in and out, use the scroll wheel or the slider on the right. Double-click the map to zoom in.

Read our open access article in the Journal of Maps about interactive video maps and how this map was created. Read more on nasa.gov about the CO ₂ model.

Interactive video map by Bernhard Jenny, Bojan Šavrič, Johannes Liem of the Cartography and Geovisualization Group, Oregon State University.

Video by NASA Goddard Space Flight Center
William M. Putman (NASA), Kayvon Sharghi (USRA), Aaron E. Lepsch (ADNET Systems, Inc.), Patrick Lynch (Wyle Information Systems)

Code on GitHub
This map projection shows all areas with correct relative size.
© 27 Dec 2014, minor updates 8 Jan 2016, 19 Sep 2016, 11 Mar 2017, 27 Nov 2017.

This video map has received the following awards:

Read our open access article in the Journal of Maps about interactive video maps and how this map was created.

Carbon Dioxide Column Concentration (ppmv)

377 379 381 383 385 387 389 391 393 395

Carbon Monoxide Column Abundance (1.0e18 molec cm⁻²)

0.0 0.6 1.2 1.8 2.4 3 3.6 4.2 4.8 5.4 6.0

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A colorful, narrated and interactive video map with adjustable map projection by NASA and Oregon State University.

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A platform to explore and visualize the most up-to-date data on carbon fluxes resulting from human activities and natural processes

Explore and download global and country level CO₂ emissions from human activity

Explore and download global and country level CO₂ emissions from human activity

Global Carbon Budget, 2022 Edition

The atmospheric CO₂ growth rate, resulting from CO₂ emissions from human activities and uptake by the land and ocean reservoirs.

Global Methane Budget, the last two decades

A new synthesis contributed by 68 research institutes, covers different regions and sectors, and the recent trends of methane emissions and sinks, using atmospheric observations and bottom-up models.

The River Loop of the Global Carbon Cycle

The journey of carbon from soils to oceans, leading to CO₂ outgassing by rivers and lakes. Data collected by the C-CASCADES project.

Explore the Global CO₂ Budget and the Global CH₄ Budget.

Explore the Global CO₂ Budget and the Global CH₄ Budget.

Global Carbon Budget, 2022 Edition

The atmospheric CO₂ growth rate, resulting from CO₂ emissions from human activities and uptake by the land and ocean reservoirs.

Global Methane Budget, the last two decades

A new synthesis contributed by 68 research institutes, covers different regions and sectors, and the recent trends of methane emissions and sinks, using atmospheric observations and bottom-up models.

The River Loop of the Global Carbon Cycle

The journey of carbon from soils to oceans, leading to CO₂ outgassing by rivers and lakes. Data collected by the C-CASCADES project.

CARBON MONITOR, Daily fossil fuel CO₂ Emissions and the COVID pandemics

Discover how the unfolding COVID-19 pandemics is reducing emissions worldwide and across different countries and sectors.

A New Dataset of Global Cities CO₂ Emissions and their Drivers

In collaboration with the Carbon Disclosure Project ( CDP), it represents CO₂ emissions from 343 cities across all continents. The data set published in Nangini et al. 2019

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A platform to explore and visualize the most up-to-date data on carbon fluxes resulting from human activities and natural processes

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University of Kentucky Center for Applied Energy Research - Carbon Materials - Carbon History and Timeline

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The Center for Applied Energy Research (CAER) is one of the University of Kentucky's multidisciplinary research centers. Its energy research provides a focal point for coal and environmental research in Kentucky. Research efforts are directed to: coal cleaning, beneficiation, utilization, and conversion process technologies.

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This page contains archived content and is no longer being updated. At the time of publication, it represented the best available science.

The Carbon Cycle

By Holli Riebeek Design by Robert Simmon

Carbon is the backbone of life on Earth. We are made of carbon, we eat carbon, and our civilizations-our economies, our homes, our means of transport-are built on carbon. We need carbon, but that need is also entwined with one of the most serious problems facing us today: global climate change.

Forged in the heart of aging stars, carbon is the fourth most abundant element in the Universe. Most of Earth's carbon-about 65,500 billion metric tons-is stored in rocks. The rest is in the ocean, atmosphere, plants, soil, and fossil fuels.

Carbon flows between each reservoir in an exchange called the carbon cycle, which has slow and fast components. Any change in the cycle that shifts carbon out of one reservoir puts more carbon in the other reservoirs. Changes that put carbon gases into the atmosphere result in warmer temperatures on Earth.

Over the long term, the carbon cycle seems to maintain a balance that prevents all of Earth's carbon from entering the atmosphere (as is the case on Venus) or from being stored entirely in rocks. This balance helps keep Earth's temperature relatively stable, like a thermostat.

This thermostat works over a few hundred thousand years, as part of the slow carbon cycle. This means that for shorter time periods-tens to a hundred thousand years-the temperature of Earth can vary. And, in fact, Earth swings between ice ages and warmer interglacial periods on these time scales. Parts of the carbon cycle may even amplify these short-term temperature changes.

On very long time scales (millions to tens of millions of years), the movement of tectonic plates and changes in the rate at which carbon seeps from the Earth's interior may change the temperature on the thermostat. Earth has undergone such a change over the last 50 million years, from the extremely warm climates of the Cretaceous (roughly 145 to 65 million years ago) to the glacial climates of the Pleistocene (roughly 1.8 million to 11,500 years ago). [See Divisions of Geologic Time-Major Chronostratigraphic and Geochronologic Units for more information about geological eras.]

The Slow Carbon Cycle

Through a series of chemical reactions and tectonic activity, carbon takes between 100-200 million years to move between rocks, soil, ocean, and atmosphere in the slow carbon cycle. On average, 10 ¹³ to 10 ¹⁴ grams (10-100 million metric tons) of carbon move through the slow carbon cycle every year. In comparison, human emissions of carbon to the atmosphere are on the order of 10 ¹⁵ grams, whereas the fast carbon cycle moves 10 ¹⁶ to 10 ¹⁷ grams of carbon per year.

The movement of carbon from the atmosphere to the lithosphere (rocks) begins with rain. Atmospheric carbon combines with water to form a weak acid-carbonic acid-that falls to the surface in rain. The acid dissolves rocks-a process called chemical weathering-and releases calcium, magnesium, potassium, or sodium ions. Rivers carry the ions to the ocean.

In the ocean, the calcium ions combine with bicarbonate ions to form calcium carbonate, the active ingredient in antacids and the chalky white substance that dries on your faucet if you live in an area with hard water. In the modern ocean, most of the calcium carbonate is made by shell-building (calcifying) organisms (such as corals) and plankton (like coccolithophores and foraminifera). After the organisms die, they sink to the seafloor. Over time, layers of shells and sediment are cemented together and turn to rock, storing the carbon in stone-limestone and its derivatives.

Only 80 percent of carbon-containing rock is currently made this way. The remaining 20 percent contain carbon from living things (organic carbon) that have been embedded in layers of mud. Heat and pressure compress the mud and carbon over millions of years, forming sedimentary rock such as shale. In special cases, when dead plant matter builds up faster than it can decay, layers of organic carbon become oil, coal, or natural gas instead of sedimentary rock like shale.

The slow cycle returns carbon to the atmosphere through volcanoes. Earth's land and ocean surfaces sit on several moving crustal plates. When the plates collide, one sinks beneath the other, and the rock it carries melts under the extreme heat and pressure. The heated rock recombines into silicate minerals, releasing carbon dioxide.

When volcanoes erupt, they vent the gas to the atmosphere and cover the land with fresh silicate rock to begin the cycle again. At present, volcanoes emit between 130 and 380 million metric tons of carbon dioxide per year. For comparison, humans emit about 30 billion tons of carbon dioxide per year-100-300 times more than volcanoes-by burning fossil fuels.

Chemistry regulates this dance between ocean, land, and atmosphere. If carbon dioxide rises in the atmosphere because of an increase in volcanic activity, for example, temperatures rise, leading to more rain, which dissolves more rock, creating more ions that will eventually deposit more carbon on the ocean floor. It takes a few hundred thousand years to rebalance the slow carbon cycle through chemical weathering.

However, the slow carbon cycle also contains a slightly faster component: the ocean. At the surface, where air meets water, carbon dioxide gas dissolves in and ventilates out of the ocean in a steady exchange with the atmosphere. Once in the ocean, carbon dioxide gas reacts with water molecules to release hydrogen, making the ocean more acidic. The hydrogen reacts with carbonate from rock weathering to produce bicarbonate ions.

Before the industrial age, the ocean vented carbon dioxide to the atmosphere in balance with the carbon the ocean received during rock weathering. However, since carbon concentrations in the atmosphere have increased, the ocean now takes more carbon from the atmosphere than it releases. Over millennia, the ocean will absorb up to 85 percent of the extra carbon people have put into the atmosphere by burning fossil fuels, but the process is slow because it is tied to the movement of water from the ocean's surface to its depths.

In the meantime, winds, currents, and temperature control the rate at which the ocean takes carbon dioxide from the atmosphere. (See The Ocean's Carbon Balance on the Earth Observatory.) It is likely that changes in ocean temperatures and currents helped remove carbon from and then restore carbon to the atmosphere over the few thousand years in which the ice ages began and ended.

The Fast Carbon Cycle

The time it takes carbon to move through the fast carbon cycle is measured in a lifespan. The fast carbon cycle is largely the movement of carbon through life forms on Earth, or the biosphere. Between 10 ¹⁵ and 10 ¹⁷ grams (1,000 to 100,000 million metric tons) of carbon move through the fast carbon cycle every year.

Carbon plays an essential role in biology because of its ability to form many bonds-up to four per atom-in a seemingly endless variety of complex organic molecules. Many organic molecules contain carbon atoms that have formed strong bonds to other carbon atoms, combining into long chains and rings. Such carbon chains and rings are the basis of living cells. For instance, DNA is made of two intertwined molecules built around a carbon chain.

The bonds in the long carbon chains contain a lot of energy. When the chains break apart, the stored energy is released. This energy makes carbon molecules an excellent source of fuel for all living things.

Plants and phytoplankton are the main components of the fast carbon cycle. Phytoplankton (microscopic organisms in the ocean) and plants take carbon dioxide from the atmosphere by absorbing it into their cells. Using energy from the Sun, both plants and plankton combine carbon dioxide (CO ₂) and water to form sugar (CH ₂ O) and oxygen. The chemical reaction looks like this:

Four things can happen to move carbon from a plant and return it to the atmosphere, but all involve the same chemical reaction. Plants break down the sugar to get the energy they need to grow. Animals (including people) eat the plants or plankton, and break down the plant sugar to get energy. Plants and plankton die and decay (are eaten by bacteria) at the end of the growing season. Or fire consumes plants. In each case, oxygen combines with sugar to release water, carbon dioxide, and energy. The basic chemical reaction looks like this:

In all four processes, the carbon dioxide released in the reaction usually ends up in the atmosphere. The fast carbon cycle is so tightly tied to plant life that the growing season can be seen by the way carbon dioxide fluctuates in the atmosphere. In the Northern Hemisphere winter, when few land plants are growing and many are decaying, atmospheric carbon dioxide concentrations climb. During the spring, when plants begin growing again, concentrations drop. It is as if the Earth is breathing.

Changes in the Carbon Cycle

Left unperturbed, the fast and slow carbon cycles maintain a relatively steady concentration of carbon in the atmosphere, land, plants, and ocean. But when anything changes the amount of carbon in one reservoir, the effect ripples through the others.

In Earth's past, the carbon cycle has changed in response to climate change. Variations in Earth's orbit alter the amount of energy Earth receives from the Sun and leads to a cycle of ice ages and warm periods like Earth's current climate. (See Milutin Milankovitch.) Ice ages developed when Northern Hemisphere summers cooled and ice built up on land, which in turn slowed the carbon cycle. Meanwhile, a number of factors including cooler temperatures and increased phytoplankton growth may have increased the amount of carbon the ocean took out of the atmosphere. The drop in atmospheric carbon caused additional cooling. Similarly, at the end of the last Ice Age, 10,000 years ago, carbon dioxide in the atmosphere rose dramatically as temperatures warmed.

Shifts in Earth's orbit are happening constantly, in predictable cycles. In about 30,000 years, Earth's orbit will have changed enough to reduce sunlight in the Northern Hemisphere to the levels that led to the last ice age.

Today, changes in the carbon cycle are happening because of people. We perturb the carbon cycle by burning fossil fuels and clearing land.

When we clear forests, we remove a dense growth of plants that had stored carbon in wood, stems, and leaves-biomass. By removing a forest, we eliminate plants that would otherwise take carbon out of the atmosphere as they grow. We tend to replace the dense growth with crops or pasture, which store less carbon. We also expose soil that vents carbon from decayed plant matter into the atmosphere. Humans are currently emitting just under a billion tons of carbon into the atmosphere per year through land use changes.

Without human interference, the carbon in fossil fuels would leak slowly into the atmosphere through volcanic activity over millions of years in the slow carbon cycle. By burning coal, oil, and natural gas, we accelerate the process, releasing vast amounts of carbon (carbon that took millions of years to accumulate) into the atmosphere every year. By doing so, we move the carbon from the slow cycle to the fast cycle. In 2009, humans released about 8.4 billion tons of carbon into the atmosphere by burning fossil fuel.

Since the beginning of the Industrial Revolution, when people first started burning fossil fuels, carbon dioxide concentrations in the atmosphere have risen from about 280 parts per million to 387 parts per million, a 39 percent increase. This means that for every million molecules in the atmosphere, 387 of them are now carbon dioxide-the highest concentration in two million years. Methane concentrations have risen from 715 parts per billion in 1750 to 1,774 parts per billion in 2005, the highest concentration in at least 650,000 years.

Effects of Changing the Carbon Cycle

All of this extra carbon needs to go somewhere. So far, land plants and the ocean have taken up about 55 percent of the extra carbon people have put into the atmosphere while about 45 percent has stayed in the atmosphere. Eventually, the land and oceans will take up most of the extra carbon dioxide, but as much as 20 percent may remain in the atmosphere for many thousands of years.

The changes in the carbon cycle impact each reservoir. Excess carbon in the atmosphere warms the planet and helps plants on land grow more. Excess carbon in the ocean makes the water more acidic, putting marine life in danger.

Atmosphere

It is significant that so much carbon dioxide stays in the atmosphere because CO ₂ is the most important gas for controlling Earth's temperature. Carbon dioxide, methane, and halocarbons are greenhouse gases that absorb a wide range of energy-including infrared energy (heat) emitted by the Earth-and then re-emit it. The re-emitted energy travels out in all directions, but some returns to Earth, where it heats the surface. Without greenhouse gases, Earth would be a frozen -18 degrees Celsius (0 degrees Fahrenheit). With too many greenhouse gases, Earth would be like Venus, where the greenhouse atmosphere keeps temperatures around 400 degrees Celsius (750 Fahrenheit).

Because scientists know which wavelengths of energy each greenhouse gas absorbs, and the concentration of the gases in the atmosphere, they can calculate how much each gas contributes to warming the planet. Carbon dioxide causes about 20 percent of Earth's greenhouse effect; water vapor accounts for about 50 percent; and clouds account for 25 percent. The rest is caused by small particles (aerosols) and minor greenhouse gases like methane.

Water vapor concentrations in the air are controlled by Earth's temperature. Warmer temperatures evaporate more water from the oceans, expand air masses, and lead to higher humidity. Cooling causes water vapor to condense and fall out as rain, sleet, or snow.

Carbon dioxide, on the other hand, remains a gas at a wider range of atmospheric temperatures than water. Carbon dioxide molecules provide the initial greenhouse heating needed to maintain water vapor concentrations. When carbon dioxide concentrations drop, Earth cools, some water vapor falls out of the atmosphere, and the greenhouse warming caused by water vapor drops. Likewise, when carbon dioxide concentrations rise, air temperatures go up, and more water vapor evaporates into the atmosphere-which then amplifies greenhouse heating.

So while carbon dioxide contributes less to the overall greenhouse effect than water vapor, scientists have found that carbon dioxide is the gas that sets the temperature. Carbon dioxide controls the amount of water vapor in the atmosphere and thus the size of the greenhouse effect.

Rising carbon dioxide concentrations are already causing the planet to heat up. At the same time that greenhouse gases have been increasing, average global temperatures have risen 0.8 degrees Celsius (1.4 degrees Fahrenheit) since 1880.

This rise in temperature isn't all the warming we will see based on current carbon dioxide concentrations. Greenhouse warming doesn't happen right away because the ocean soaks up heat. This means that Earth's temperature will increase at least another 0.6 degrees Celsius (1 degree Fahrenheit) because of carbon dioxide already in the atmosphere. The degree to which temperatures go up beyond that depends in part on how much more carbon humans release into the atmosphere in the future.

Ocean

About 30 percent of the carbon dioxide that people have put into the atmosphere has diffused into the ocean through the direct chemical exchange. Dissolving carbon dioxide in the ocean creates carbonic acid, which increases the acidity of the water. Or rather, a slightly alkaline ocean becomes a little less alkaline. Since 1750, the pH of the ocean's surface has dropped by 0.1, a 30 percent change in acidity.

Ocean acidification affects marine organisms in two ways. First, carbonic acid reacts with carbonate ions in the water to form bicarbonate. However, those same carbonate ions are what shell-building animals like coral need to create calcium carbonate shells. With less carbonate available, the animals need to expend more energy to build their shells. As a result, the shells end up being thinner and more fragile.

Second, the more acidic water is, the better it dissolves calcium carbonate. In the long run, this reaction will allow the ocean to soak up excess carbon dioxide because more acidic water will dissolve more rock, release more carbonate ions, and increase the ocean's capacity to absorb carbon dioxide. In the meantime, though, more acidic water will dissolve the carbonate shells of marine organisms, making them pitted and weak.

Warmer oceans-a product of the greenhouse effect-could also decrease the abundance of phytoplankton, which grow better in cool, nutrient-rich waters. This could limit the ocean's ability to take carbon from the atmosphere through the fast carbon cycle.

On the other hand, carbon dioxide is essential for plant and phytoplankton growth. An increase in carbon dioxide could increase growth by fertilizing those few species of phytoplankton and ocean plants (like sea grasses) that take carbon dioxide directly from the water. However, most species are not helped by the increased availability of carbon dioxide.

Land

Plants on land have taken up approximately 25 percent of the carbon dioxide that humans have put into the atmosphere. The amount of carbon that plants take up varies greatly from year to year, but in general, the world's plants have increased the amount of carbon dioxide they absorb since 1960. Only some of this increase occurred as a direct result of fossil fuel emissions.

With more atmospheric carbon dioxide available to convert to plant matter in photosynthesis, plants were able to grow more. This increased growth is referred to as carbon fertilization. Models predict that plants might grow anywhere from 12 to 76 percent more if atmospheric carbon dioxide is doubled, as long as nothing else, like water shortages, limits their growth. However, scientists don't know how much carbon dioxide is increasing plant growth in the real world, because plants need more than carbon dioxide to grow.

Plants also need water, sunlight, and nutrients, especially nitrogen. If a plant doesn't have one of these things, it won't grow regardless of how abundant the other necessities are. There is a limit to how much carbon plants can take out of the atmosphere, and that limit varies from region to region. So far, it appears that carbon dioxide fertilization increases plant growth until the plant reaches a limit in the amount of water or nitrogen available.

Some of the changes in carbon absorption are the result of land use decisions. Agriculture has become much more intensive, so we can grow more food on less land. In high and mid-latitudes, abandoned farmland is reverting to forest, and these forests store much more carbon, both in wood and soil, than crops would. In many places, we prevent plant carbon from entering the atmosphere by extinguishing wildfires. This allows woody material (which stores carbon) to build up. All of these land use decisions are helping plants absorb human-released carbon in the Northern Hemisphere.

In the tropics, however, forests are being removed, often through fire, and this releases carbon dioxide. As of 2008, deforestation accounted for about 12 percent of all human carbon dioxide emissions.

The biggest changes in the land carbon cycle are likely to come because of climate change. Carbon dioxide increases temperatures, extending the growing season and increasing humidity. Both factors have led to some additional plant growth. However, warmer temperatures also stress plants. With a longer, warmer growing season, plants need more water to survive. Scientists are already seeing evidence that plants in the Northern Hemisphere slow their growth in the summer because of warm temperatures and water shortages.

Dry, water-stressed plants are also more susceptible to fire and insects when growing seasons become longer. In the far north, where an increase in temperature has the greatest impact, the forests have already started to burn more, releasing carbon from the plants and the soil into the atmosphere. Tropical forests may also be extremely susceptible to drying. With less water, tropical trees slow their growth and take up less carbon, or die and release their stored carbon to the atmosphere.

The warming caused by rising greenhouse gases may also "bake" the soil, accelerating the rate at which carbon seeps out in some places. This is of particular concern in the far north, where frozen soil-permafrost-is thawing. Permafrost contains rich deposits of carbon from plant matter that has accumulated for thousands of years because the cold slows decay. When the soil warms, the organic matter decays and carbon-in the form of methane and carbon dioxide-seeps into the atmosphere.

Current research estimates that permafrost in the Northern Hemisphere holds 1,672 billion tons (Petagrams) of organic carbon. If just 10 percent of this permafrost were to thaw, it could release enough extra carbon dioxide to the atmosphere to raise temperatures an additional 0.7 degrees Celsius (1.3 degrees Fahrenheit) by 2100.

Studying the Carbon Cycle

Many of the questions scientists still need to answer about the carbon cycle revolve around how it is changing. The atmosphere now contains more carbon than at any time in at least two million years. Each reservoir of the cycle will change as this carbon makes its way through the cycle.

What will those changes look like? What will happen to plants as temperatures increase and climate changes? Will they remove more carbon from the atmosphere than they put back? Will they become less productive? How much extra carbon will melting permafrost put into the atmosphere, and how much will that amplify warming? Will ocean circulation or warming change the rate at which the ocean takes up carbon? Will ocean life become less productive? How much will the ocean acidify, and what effects will that have?

NASA's role in answering these questions is to provide global satellite observations and related field observations. As of early 2011, two types of satellite instruments were collecting information relevant to the carbon cycle.

The Moderate Resolution Imaging Spectroradiometer (MODIS) instruments, flying on NASA's Terra and Aqua satellites, measure the amount of carbon plants and phytoplankton turn into matter as they grow, a measurement called net primary productivity. The MODIS sensors also measure how many fires occur and where they burn.

Two Landsat satellites provide a detailed view of ocean reefs, what is growing on land, and how land cover is changing. It is possible to see the growth of a city or a transformation from forest to farm. This information is crucial because land use accounts for one-third of all human carbon emissions.

Future NASA satellites will continue these observations, and also measure carbon dioxide and methane in the atmosphere and vegetation height and structure.

All of these measurements will help us see how the global carbon cycle is changing through time. They will help us gauge the impact we are having on the carbon cycle by releasing carbon into the atmosphere or finding ways to store it elsewhere. They will show us how our changing climate is altering the carbon cycle, and how the changing carbon cycle is altering our climate.

Most of us, however, will observe changes in the carbon cycle in a more personal way. For us, the carbon cycle is the food we eat, the electricity in our homes, the gas in our cars, and the weather over our heads. We are a part of the carbon cycle, and so our decisions about how we live ripple across the cycle. Likewise, changes in the carbon cycle will impact the way we live. As each of us come to understand our role in the carbon cycle, the knowledge empowers us to control our personal impact and to understand the changes we are seeing in the world around us.

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This page contains archived content and is no longer being updated. At the time of publication, it represented the best available science. By Holli Riebeek Design by Robert Simmon Carbon is the backbone of life on Earth. We are made of carbon, we eat carbon, and our civilizations-our economies, our homes, our means of transport-are built on carbon.

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7A: C02 and Ocean pH - What's the Connection?

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Part A: CO2 and Ocean pH - What's the Connection? Oyster farmers sound the alarm about ocean acidification Oyster farmers have been on the front lines of ocean acidification. In Washington and Oregon, oysters ...

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Episode 5: Global Warming, It's All About Carbon | Krulwich Wonders | NPR

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Infographic: What Do Your Country's Emissions Look Like? (World Resources Institute) | Progressistes pour le climat

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Rheilford Dyffryn Conwy Conwy Valley Railway

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Practical actions in the uplands to benefit people and nature and to reduce problems downstream.

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A project to save a threatened Welsh eco-system which can store more greenhouse gases than the Amazon rainforest is recording impressive results according to scientists.

Miles of ditches dug on a peat bog over the last two centuries have been filled over the past two years, with the aim of storing carbon and reducing flooding in the valley below.

The £300,000 restoration work on the Migneint upland bog between Ffestiniog and Llanrwst on the Gwynedd-Conwy border has been funded by the National Trust and Natural Resources Wales.

Peter Jones, of NRW said: "This is a fantastic project to restore blanket bog in one of the most important areas for it in the UK.

"The work will help restore the bogs to a favourable condition which will maximise the wider environmental benefits associated with healthy peatlands, including carbon storage and locking up the carbon dioxide from the atmosphere."

A 300-kilometre network of ditches crisscrossing the area has been closed and 30,000 dams created to restore the bog and enable it to again function naturally.

The Migneint is Wales' second largest moorland and is also a European-designated special conservation area.

The ditches had been used for drying out the bog for sheep pasture and grouse shooting.

Now the wet and sponge-like nature of the Migneint has been restored.

Andrew Roberts, Lead Ranger for the National Trust in south Snowdonia, has worked in the area for more than 30 years.

"This has been a very important project and we are already seeing results that benefit the environment in a number of ways," he said.

"The bog is giving off less carbon, the water quality has improved, nearby residents have told us they've had less problems with flooding and the area is safer for livestock.

"The manmade drains and ditches were very dangerous to livestock, a number of corpses were found during the project to restore the area.

"Livestock grazing is a very effective way of managing the habitat and we will be working with the farming community to actively encourage this now it is safe to do so."

Like tropical rainforests, peatlands are associated with tackling global warming.

Healthy peatlands can store more carbon than the Amazon, achieving greater environmental benefits by both holding carbon in their peat profiles and locking up atmospheric carbon in the form of new peat.

Damaged peatlands on the other hand give off harmful CO2 emissions.

The Special Area of Conservation section that contains the restoration site covers an area of 20,000 hectares. It is estimated the project has reduced CO2 emissions from the bog by 2.6 tonnes per hectare - the equivalent of running a family car for a year.

Several agencies have been assessing the benefits of retaining a high water table in the peat. Among them is the Bangor-based Centre for Ecology and Hydrology.

Dr Ed Rowe was a part of the original team interested in keeping carbon dioxide, a known greenhouse gas capable of causing climate change, locked in the Migneint soil.

He said: "The thing about Welsh bogs is that they have a great amount of carbon stored in them, something like 70 times the amount that cars and vehicles in Wales use in a year.

"So it's very important we keep that carbon in place. "

Professor Chris Evans, a researcher at the Centre for Ecology and Hydrology in Bangor, said: "From the outset, the National Trust has done everything it can to support our scientific research alongside their restoration work, helping us to better understand what restoring peatlands will achieve for greenhouse gas emissions and water quality.

"Defra has funded a major field experiment on the National Trust's estate, which means the work taking place here should help to improve national policies as well as the local environment."

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The National Trust project to save a threatened Welsh ecosystem

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A project to save a threatened Welsh eco-system which can store more greenhouse gases than the Amazon rainforest is recording impressive results according to scientists. Miles of ditches dug on a peat bog over the last two centuries have been filled over the past two years, with the aim of storing carbon and reducing flooding in the valley below.

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Originally posted on From inside the shell:
By Edward A. D. Mitchell, Laboratory of Soil Biodiversity, University of Neuchâtel, Switzerland With the advent of high throughput sequencing, estimates of global...

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Originally posted on From inside the shell: By Edward A. D. Mitchell, Laboratory of Soil Biodiversity, University of Neuchâtel, Switzerland With the advent of high throughput sequencing, estimates of global...