Carbon currency – the credits and debits of carbon emissions tradingThe Kyoto Protocol is the first step towards stabilising global emissions of carbon dioxide. But what is carbon emissions trading and will it limit the enhanced greenhouse effect?
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Key textImagine you are a farmer in the Australian wheat belt. You need to plant trees to arrest salinity, erosion and soil acidification, but you can’t afford to – trees usually don’t earn you money for many years, if ever. Then, along comes a carbon broker. He offers to pay you money up-front to plant trees. In return, he wants a credit for the carbon such trees will store. You plant the trees and pocket the cash. As more and more farmers switch to trees, the wheat belt becomes more like a belt of living carbon.That is the dream of some Australian farmers, foresters and entrepreneurs. They believe that a system of carbon emissions trading that allows the buying and selling of carbon 'credits' will simultaneously help prevent global warming and promote the planting of trees on degraded land. The greenhouse effect We owe our presence on Earth to carbon dioxide (CO2) and other greenhouse gases. Spewed out from below the Earth’s crust before life began, CO2 helped stabilise temperatures to levels suitable for organic life. It did this – and continues to do it – by what is known as the greenhouse effect. This occurs when heat energy from the sun passes unimpeded through the atmosphere and warms up the Earth. In turn, the Earth radiates this energy back towards space. The greenhouse gases – water vapour (the main greenhouse gas), methane, ozone, carbon monoxide, nitrous oxide and CO2 – absorb some of this energy and emit it in all directions, including back towards Earth. The Earth's surface is about 34ºC warmer as a result. Over millions of years, the Earth has managed to regulate concentrations of greenhouse gases through a system of sources and sinks. Carbon (in the form of CO2 and methane) is emitted by volcanoes and by rotting vegetation and other organic matter. But CO2 is sequestered, or absorbed, by trees (their roots, branches, trunks and leaves are about 50 per cent carbon), plankton, soils and water bodies. Indeed, scientists have become aware that increased concentrations of CO2 actually stimulate the growth of many different types of plant, including trees – this is called the CO2 fertilisation effect. For example, a doubling of atmospheric CO2 has been shown to stimulate leaf photosynthesis rate by up to 50 per cent depending on temperature. Although some of this CO2 will be released back into the atmosphere by increased respiration, more carbon should be sequestered. So, if a series of volcanic eruptions or burning of fossil fuels emitted excess CO2, in time it would be partly ‘mopped up’ by the increased growth of forests, and partly dissolved in the oceans. Enhanced greenhouse effect In modern times the burning of fossil fuels like coal, oil and natural gas – in which carbon has been stored for millions of years – combined with accelerated land clearance has led to unprecedented levels of greenhouse gas emissions. Carbon sinks can’t keep up, and concentrations of greenhouse gases in the atmosphere have risen dramatically leading to an enhanced greenhouse effect. Most scientists say that as concentrations of these gases continue to rise, there will be a general and very rapid warming of the world’s climate. No one is sure what effect this warming will have on the details of regional climate, but predictions include widespread ecological changes in agricultural production, and rising sea levels. While not all model predictions are so dire, the possibility of costly disruption from rapid climate change calls for greater attention and precautionary measures to be put in place. Waking up to warming – slowly People have become increasingly concerned about the possible effects of global warming. Although the annual rate of emissions has been decreasing, the CO2 concentration in the atmosphere is still increasing. In 1992, most developed countries in the world agreed to the United Nations Framework Convention on Climate Change (UNFCCC), which is designed to impose limits on greenhouse gas emissions and thus minimise the adverse effects of climate change (Box 1: International deliberations). But experience has shown that reducing the use of fossil fuels is a slow process. In Australia, which relies heavily on coal for its power supplies, only 9 per cent of our energy comes from renewable and non-greenhouse sources; the government hopes to increase this to 11 per cent by 2010 (Box 2: Australia's policy response). Scientists predict that we need to decrease global CO2 emissions by at least 50 per cent of current levels by 2050 to stabilise global carbon dioxide levels and prevent further climate change. Are there alternatives to cutting back on fossil fuels? For example, what if we were to grow more forests, or not cut down trees that we might otherwise have, thereby removing carbon from the atmosphere? While recognising that it is only a partial solution, negotiations conducted by all the countries that have signed the UNFCCC are paving the way for this possibility. Some people hail it as a way of simultaneously cutting concentrations of atmospheric greenhouse gases and promoting reforestation. Others see it as a tactic to delay the time when countries have to deal with the issue of burning fossil fuels – by which time the problem may be much worse. A formula to limit emissions Under the Kyoto Protocol, developed countries such as Australia are required to limit their greenhouse gas emissions according to the following formula: actual emissions must be less than or equal to the assigned amount +/- carbon sinks and Kyoto emissions. We won’t attempt to decode this fully here; what concerns us most is the ‘carbon sinks’ part of the formula. It means that Australia can emit more than its assigned amount (which, incidentally, is 8 per cent above its emissions in 1990) if it can simultaneously sequester the equivalent amount in sinks. Allowable carbon sinks Under the Kyoto Protocol, allowable carbon sinks include afforestation and reforestation activities undertaken since 1990. Agricultural soils and some other sources and sinks may also be included, although these are yet to be agreed to. Part of the difficulty with including these is scientific – measuring changes in soil carbon on agricultural land, for example, remains extremely problematic – demonstrating that compliance will be a problem. Geosequestration is another option being investigated as a possible sink for carbon in Australia and other countries with suitable geology. Carbon emissions trading What does this all have to do with carbon emissions trading? Under the UNFCCC, countries are permitted to use a trading system to help meet their emissions targets. In principle, a country may allocate permits to individual companies for the emission of a certain quantity of greenhouse gases. If permits are only issued to a level equal to or below the assigned amount, then a country should meet its Kyoto commitment (assuming that the measures of its emissions are accurate). If a country is incapable of meeting its target, it can buy permits from countries that are under their targets. Similarly, companies within a country that prove more able to reduce their emissions are allowed to ‘trade’ excess permits to other, more polluting, enterprises. Where carbon credits come in The trading system involves the issuing of carbon credits for afforestation and reforestation activities. It requires an assessment to answer questions such as: Was the forest established after 1990? How quickly is it growing? How much carbon is it sequestering? Credits are issued to the individual or company growing the forests. These credits can be sold to a carbon emitter such as a power company, using them to ‘offset’ its excessive carbon emissions. The scientific questions Part of the reason for global warming is excessive land clearing, so is restoring vegetation cover part of the solution? Vegetation, largely forest, is already absorbing about one-third of human-induced emissions, planting more forests could increase absorption. Some caution is required because accounting for the carbon contained in forests is difficult. The amount of carbon in forest soils, forest litter and the trees themselves needs to be measured. Different types of trees store different amounts of carbon when growing on different types of soils in different climates. In addition, we might expect natural year-to-year variations in carbon stored, related to climate variations. And there is the added difficulty of monitoring the long-term fate of carbon – will the sink become a source? Consider what happens in a plantation harvested for pulp. Much of the carbon stored in the roots, leaves, bark and branches of trees is released into the atmosphere as the dead vegetation rots. The stems are turned into pulp, which is manufactured into a range of paper and wood fibre products. Many of these are used once and then discarded – they will also rot or be incinerated, returning their carbon to the atmosphere. Even trees harvested for long-term uses such as furniture and house frames will lose a large proportion of their stored carbon to the atmosphere through waste during processing. Planting trees for conservation purposes – where they are unlikely to ever be harvested – will be of more long-term benefit to the global carbon cycle than will plantings for some commercial harvesting (eg, trees for pulping). But even trees for conservation purposes may be lost in a forest fire – and most of the stored carbon would return to the atmosphere. Furthermore, a new forest acts as a sink only until it reaches maturity, at which time new growth is compensated by death and decay. To help account for carbon flow, the Australian Greenhouse Office, the CSIRO and the Australian National University have developed methods to reliably measure greenhouse gas emissions. The methods calculate emissions resulting from variables such as soil cultivation, fire management, fertiliser application, climate, different plant species and land management systems. Methods for measuring emissions are evolving and improving as a result of new research. Carbon accounting in Australia Australia is dealing with issues of carbon accounting. Many research institutions – including the Cooperative Research Centre for Greenhouse Accounting, the Cooperative Research Centre for Greenhouse Gas Technologies and the Australian Greenhouse Office – are developing knowledge to underpin an acceptable approach by Australia. One area of investigation is to determine the degree to which the CO2 fertilisation effect can help to sequester Australia's CO2 emissions. To explain the fertilisation effect, we need to take a quick look at photosynthesis. Photosynthesis and the CO2 fertilisation effect The basic ingredients for photosynthesis are CO2, water and energy (in the form of sunlight). In addition, several nutrients such as nitrogen and phosphorus are required for the manufacture of essential proteins. Photosynthesis will increase if the availability of these ingredients increases. This explains the CO2 fertilisation effect – as more CO2 becomes available, more growth can take place and more carbon is sequestered. But basic plant physiology and ecosystem experiments show that the fertilisation effect of increasing concentrations of CO2 eventually reaches a saturation point. This means that other vital ingredients such as water and nutrients become limiting. Clearly, when reafforestation is used as a method for storing carbon, it can only occur when sufficient water and nutrients are available. The same applies for the CO2 fertilisation sink, except that elevated CO2 increases the efficiency of use of water and nutrients in fostering carbon sequestration. The next phase The pros and cons of carbon credits continue to be debated by the international community. The Sydney Futures Exchange has established a carbon credits trading market and many carbon emitters are buying credits from forest growers. While forests are an important carbon sink, there is a limit to the amount of carbon that they can store. The largest carbon sink is in the fossil fuels in the ground, but we are currently using them as a major source of energy and emitting CO2 into the atmosphere as a result. A number of changes are needed to achieve a substantial decrease in emissions. It will require reduced energy demand, increased energy efficiency, using less fossil fuels and more renewable energy sources. It will also require research and development of sustainable technologies that reduce carbon emissions. If carbon emissions trading becomes a widespread phenomenon, we will probably see big changes in the Australian countryside. For 200 years we have worked hard to get rid of our trees because they hindered agriculture. Now we know that they deserve a bit more credit than that.
The prospect of an enhanced greenhouse effect has generated plenty of heat between national governments. The development of international policies to address greenhouse – and the responses of governments to these policies – is a fascinating subject in its own right. In the 1980s the World Meteorological Organization and the United Nations Environment Programme established an international panel of government representatives and scientists to review the science of climate change. Known as the Intergovernmental Panel on Climate Change (IPCC), it has published numerous extensive reports that have become the source for much of the material used in discussions and decision-making about the enhanced greenhouse effect. At the 1992 Earth Summit in Rio de Janeiro, Australia and about 150 other countries signed the UN Framework Convention on Climate Change. Australia ratified the convention in December 1992. As a party to the convention, Australia must report its greenhouse gas emissions and the strategies and measures it has adopted to reduce them. The stated objective of the Framework Convention is to achieve The countries party to the UN Framework Convention on Climate Change met in Berlin in early 1995 in what is known as the first meeting of the Conference of the Parties (COP1). They agreed to continue cooperating internationally on the enhanced greenhouse effect. But there was little agreement on what measures could be implemented. After much negotiation, delegates started work on a protocol. COP2 was held in July 1996 in Geneva. There, the countries agreed that talks on reducing greenhouse gas emissions should be accelerated. Earth Summit II in New York in June 1997 reviewed how successfully Earth Summit I commitments had been implemented in the 5 years since they were agreed to. Australia’s opposition to legally binding, uniform targets on greenhouse gas emissions received international criticism. The Australian Government argued that all nations start at a different base with respect to greenhouse gases. For example, some countries have copious supplies of hydroelectricity, others depend on inputs of energy-intensive methods, still others have economies that are less energy dependent. Within the European Union differential targets were allowed for these and other reasons. Thus, in this regard, Australia's approach was not that different. COP3 took place in Kyoto, Japan in December 1997, resulting in the Kyoto Protocol. This agreement sets the collective global target of reducing greenhouse gas emissions by about 5 per cent of 1990 levels by 2012. Australia, which argued that it was a special case because of increasing population, dependence on fossil fuels and a decentralised economy, had its target set at 8 per cent above 1990 levels. COP4 took place in Buenos Aires, Argentina in November 1998, where a 2-year plan of action was adopted to reduce the risk of global climate change. COP5 was held in Bonn, Germany in October/November 1999. Progress was made on the following issues: accelerating the negotiation process; Kyoto mechanisms; land-use, land use change and forestry; and compliance. In November 2000, negotiations were suspended at COP6 when no agreement was reached on rules to make the Kyoto Protocol operational. COP6 resumed in July 2001 in Bonn, Germany. Although the United States was not part of the talks, other industrialised nations reached partial agreement about how to begin addressing the problem of climate change. At COP7, held in Marrakesh, Morocco in November 2001, extended discussions produced a rule book for the Kyoto Protocol, clearing the way for ratification. COP 8 was held in Delhi, India in October 2002, where participants urged that the Kyoto Protocol be brought into force as quickly as possible, and agreed on procedural rules related to documentation and reporting of emissions. Discussions on the obligations of developing countries to meet emissions targets were heated. At COP 9, held in Milan, Italy in December 2003, there was a call for Russia to ratify the protocol, discussion about technicalities relating to carbon sinks and the formation of two funds to assist developing countries. COP 10 was held in Buenos Aires, Argentina in December 2004, and focused on preparation for the implementation of the Kyoto Protocol, after Russia agreed to ratify the protocol. There was discussion about bringing existing policies into force and the next phase of negotiations, without any new commitments being made beyond 2012. The Kyoto Protocol came into force on 16 February 2005. The attention of advocates of the protocol has now turned to strengthening the agreement for the years following the initial commitment period of 2008 to 2012. One of the challenges is to include all of the major emitting countries, both developed and developing. Another is to begin significant long term reductions in carbon emissions to prevent further climate change. Related site
The National Greenhouse Response Strategy was replaced in late 1996 by the National Greenhouse Strategy. It is the primary mechanism through which our international commitments will be met. Under this strategy, a number of programs have been launched or continued. For example, the Greenhouse Challenge Plus, launched in March 2005, is a cooperative effort between Australian industry and the Commonwealth Government to reduce greenhouse emissions through voluntary industry action. Around 780 Australian companies are part of the program. Another scheme allows carbon 'pooling' so that growers of small forests can group together to participate in abatement programs. Australia signed the Kyoto Protocol in 1998, but the agreement was not ratified until December 2007. In 2004 and 2005, the National Greenhouse Gas Inventory – the annual statistical report on greenhouse gas emissions – stated that Australia had achieved 101 per cent increase in emissions and is on course to meet the target emissions. While this is an increase in emissions, if business had continued 'as usual' the emissions would be 125 per cent of 1990 levels by 2008-2012. The difference between what has been achieved and what would have occurred without change in policy is equivalent to removing every car in Australia from the road. The response of the New South Wales and Australian Capital Territory governments About half of Australia's carbon emissions come from coal-fired electricity generating stations. Unlike many countries, we do not have nuclear power stations or large hydro schemes to produce electricity. In Australia, NSW and the ACT are the only states to have mandatory Greenhouse Gas Abatement Schemes. The NSW scheme was introduced in January 2003 and the ACT scheme in January 2005. Both schemes are interlinked and involve cooperation between the states. Electricity retailers must now meet mandatory targets for reducing the emission of greenhouse gases from the production of the electricity they supply or use. The NSW and ACT targets for emissions are 7.27 and 7.97 tonnes of carbon dioxide equivalent per capita by 2007. This target is 5 per cent below the level determined in the Kyoto Protocol baseline year of 1990. The target levels will be maintained until at least 2012. If participants fail to meet targets, they will pay a penalty per tonne of emissions above their targets. Abatement certificates are issued by accredited organisations for low-emission generation of electricity, reduced consumption of electricity and capture of carbon from the atmosphere by forests. Each certificate is equivalent to 1 tonne of CO2 equivalent associated with the consumption of electricity. Related sites
Australasian Science September 2007, pages 37-38 The great carbon trading swindle (by Simon Grose) Discusses the exercise of carbon trading.
July 2007, page 15 Success for carbon storage Explores the use of a slow pyrolysis process to generate charcoal for compost applications.
March 2006, page 6 Does methane sink forests as carbon sinks? Looks at the finding that trees produce a substantial amount of methane.
May 2005, pages 34-36 How to reduce CO2 emissions by 50% (by Mark Diesendorf) Argues that efficient energy use and existing renewable energy technologies could replace most of Australia’s coal-fired power stations.
March 2004, pages 36-37 Greenhouse gases fuel photosynthesis too (by Derek Eamus) Outlines the ecological and economic consequences of climate change on plant growth.
Ecos Issue 134, 2007 pages 12-15 The economic impacts of deep cuts to Australia's greenhouse emissions Suggests that emissions can be cut with minimal economic and social impact.
No. 132, 2006, page 5 AFL goes carbon neutral Describes the Australian Football League's 'AFL Green' program to neutralise an estimated 120 000 tonnes of greenhouse emissions generated from AFL events over the next three years.
No. 132, 2006, page 5 Emission reducing technology pays off Says that PLASCONTM technology, developed in Australia by CSIRO and SRL Plasma Ltd, is reducing greenhouse emissions and providing a handsome pay back.
No. 132, 2006, pages 34-35 Vegetation carbon stock has doubled since 1788 (by Steve Davidson) Researchers have found that the total carbon stock in the living vegetation may have doubled since European settlement in Australia.
No. 131, 2006, page 5 Centrelink's fleet car forest Describes the efforts of Centrelink to offset the emissions of its fleet vehicles.
No. 130, 2006, page 7 Trialing a 90% capture of coal power's CO2 Describes the trial of new technology to capture and liquefy CO2 emitted from coal-fired power stations.
No. 130, 2006, page 34 Cooperation on capturing China's mine methane emissions Describes a project to develop technology to burn methane emitted by coal mines in China.
No. 128, 2006, page 5 HSBC on track with carbon credits in Australia and New Zealand Looks at the efforts of a bank to become carbon neutral by 2006.
No. 128, 2006, pages 8-11 The first cut must be the deepest (by Michael Smith and Karlson Hargroves) Argues that radical cuts in greenhouse emissions can be economically achieved by 2050.
No. 124, 2005, pages 4-5 Greenhouse gas levels in reach with action and new technology Suggests that Australia can stabilize its emissions within ten years using current technologies.
No. 123, 2005, pages 15-17 Air transport impacts take off (by Steve Davidson) Discusses the growth of the aviation industry and the need for controls on emissions.
Issues September 2004 Taming transport (by Paul Mees) Discusses how to reduce greenhouse emissions from transport.
September 2004 How to replace the worst greenhouse gas of all Describes new Australian technology that will cut the production of sulfur hexafluoride, the most powerful warming gas of all.
Issues in Science and Technology Fall 2005 The case for carbon capture and storage (by Jennie Stephens and Bob Van Der Zwaan) Presents arguments in favour of carbon capture and storage by the USA.
New Scientist April 2008, page 11 Digital diet (by David Biello) Investigates energy conservation in the computing industry.
21 July 2007, page 6 Australia announces 'cap and trade' CO2 scheme Reports on announcement of a national greenhouse gas emissions scheme.
25 April 2007 China's emissions may surpass the US in 2007 (by Catherine Brahic) Looks at China’s growing greenhouse gas emissions and negotiations for a post Kyoto climate treaty.
10 March 2007, pages 38-41 Look, no footprint (by Fred Pearce) Ask whether you can really cleanse your carbon sins by paying for a few faraway trees and solar panels.
20 February 2007 EU agrees to cut greenhouse emissions by 20% (by Catherine Brahic and Reuters) Discusses an EU decision to have an agreement in place beyond 2012 when the Kyoto protocol expires.
14 February 2007 China to promise cuts in greenhouse gases (by Catherine Brahic) Looks at China’s first program to cut its emissions.
10 February 2007, pages 6-9 But here’s what they didn’t tell us (by Fred Pearce) Discusses some of the information that was not included in the 2006 IPCC report.
7 February 2007 Limits on vehicle emissions proposed by Europe (by Catherine Brahic) Looks at a proposal to enforce limits on vehicle CO2 emissions in Europe.
9 December 2006, page 10 Africa ‘barred from carbon trading’ (by Fred Pearce) Looks at ways in which farmers in developing countries can gain credit by planting trees.
2 December 2006, page 18 Carry on polluting (by Larry Lohmann) Argues that carbon trading is a licence for big polluters to continue with business as usual.
25 November 2006, page 14 174 countries, and no idea what to do after Kyoto (by Fred Pearce) Comments on the lack of certainty after the Kyoto protocol expires in 2012.
12 August 2006, page 14 Bang bang and the world warms (by Fred Pearce) Looks at the impact of burning the moors to boost grouse habitat on the release of CO2.
24 June 2006, pages 10-11 Kyoto promises are nothing but hot air (by Fred Pearce) Describes an alternative method of estimating greenhouse gas emissions, which suggests that some countries have under reported their emissions.
20 May 2006, page 8-9 Keeping the green dream alive (by Fred Pearce) Suggests that the future of the European Union carbon trading scheme depends on the response of its members.
15 April 2006, page 24 The value of trees (by William Laurance) Presents arguments in favour of paying countries in the tropics not to cut down trees to tackle global warming.
21 January 2006, pages 40-43 Something in the air (by Rowan Hooper) Looks at the problems caused by anthropogenic nitrogen in the environment and calls for a Kyoto-style agreement to control nitrogen levels.
3 December 2005, page 30 Energy diary helps correct bad habits (by Michael Fitzpatrick) Describes a personal monitor to help people become more aware of their energy use, and to cut their emissions and bills.
3 September 2005, page 30 The big clean-up (by Ben Crystall) Describes the Asia-Pacific Partnership on Clean Development and Climate which relies on technology to reduce greenhouse emissions.
17 May 2005 Post Kyoto talks start in tough climate (by Fred Pearce) Discusses how to limit greenhouse gas emissions after 2012 when the Kyoto Protocol ends.
6 January 2005 European trading in carbon-emission permits begins (by Fred Pearce) Asks if a carbon trading scheme is the way to cut greenhouse gas emissions and global warming.
Options Winter 2006, pages 20-21 Helping to understand a changing world Looks at the Siberian taiga forests as a sink for CO2.
RTD info November 2003, pages 30-34 A dead end in 30 years Comments on our continuing dependence on fossil fuels for years to come, despite concerns over energy and climate problems.
Scientific American December 2007 Making carbon markets work (by David Victor and Danny Cullenward) Looks at ways to regulate carbon dioxide emissions.
10 April 2007 More trees, less global warming, right? – Not exactly (by Nikhil Swaminathan) Reports on the findings of a 150-year simulation of worldwide deforestation.
November 2006, pages 10-11 Keeping CO2 down (by Rebecca Renner) Reports on the results of the first US project for carbon dioxide burial.
28 November 2005 Ice core extends climate record back 650,000 years (by David Biello) Analysis of a two mile long cylinder of ice representing 650,000 years of greenhouse gas emissions confirms man’s role in current atmospheric CO2 levels.
September 2005, pages 52-61 More profit with less carbon (by Amory B. Lovins) Argues that using energy efficiently can save companies money.
July 2005, pages 39-45 Can we bury global warming? (by Robert Socolow) Argues that pumping carbon dioxide underground to avoid warming the atmosphere is feasible, but only if several key challenges can be met.
February 2005 Capturing carbon dioxide (by Don Monroe) Describes how signatory nations to the Kyoto protocol will strive to curb their emissions of carbon dioxide and other heat-trapping gases.
State Forests of New South Wales (Australia)
eCarbon news (Cooperative Centre for Greenhouse Accounting, Australia)
Provides links to the latest stories on climate change, energy, emissions and sequestration from Australia and around the world.
International climate efforts beyond 2012: A survey of approaches (Pew Center on Global Climate Change, USA)
Discusses alternative approaches to mitigating climate change beyond 2012.
The United Nations Framework Convention on Climate Change
Climate and atmosphere: Country profiles (Earthtrends, World Resources Institute)
This site provides a map of the world to access climate related information (includes Australia).
Vital climate graphics (United Nations Environment Programme)
Provides links to background information on climate change, observed climate trends and the potential impacts of climate change.
Australian Broadcasting Corporation
Timeline of milestones (American Institute of Physics, USA)
Provides a timeline of important dates in the discovery of global warming.
anthropogenic. Caused or induced by humans; of human origin. Conference of the Parties (COP). Comprises all countries that have ratified the United Nations Framework Convention on Climate Change. COP is responsible for implementing the objectives of the Convention and has been meeting regularly since 1995. More information on outcomes from Conference of the Parties (COP) meetings is available at the United Nations Framework Convention on Climate Change. enhanced greenhouse effect. An increase in the natural process of the greenhouse effect, brought about by human activities, whereby greenhouse gases such as carbon dioxide, methane, chlorofluorocarbons and nitrous oxide are being released into the atmosphere at a far greater rate than would occur through natural processes and thus their concentrations are increasing. Also called anthropogenic greenhouse effect or climate change. geosequestration. Involves the capture and long-term underground storage of carbon dioxide. Carbon dioxide produced by coal-fired electricity stations and other industrial sources is compressed to form a liquid and injected into deep underground geological formations Possible storage sites include saline aquifers, coal seams, and used oil and gas reservoirs. For more information about geosequestration see What is geosequestration? (CO2 Cooperative Research Centre for Greenhouse Gas Technologies). greenhouse effect. The trapping and build-up of heat in the lower atmosphere near a planet's surface. Some of the heat flowing back towards space from the Earth's surface is absorbed by water vapour, carbon dioxide, methane and other gases in the atmosphere. If the atmospheric concentrations of these gases rises, then theory predicts that the average temperature of the lower atmosphere will gradually increase. The greenhouse effect in part explains the temperature differences of Mars, Venus and Earth. Kyoto Protocol. The third session of the Conference of the Parties to the UN Framework Convention on Climate Change took place in Kyoto, Japan in December 1997, resulting in the Kyoto Protocol. This working agreement of the signatories commits developed countries to reduce their collective emissions of six greenhouse gases by at least 5 per cent of 1990 levels by 2012. The Kyoto agreement became legally binding on 16 February 2005 when 132 signatory countries agreed to strive to decrease carbon dioxide emissions. More information can be found at the official The Kyoto Protocol site. photosynthesis. The biochemical process in which green plants (and some microorganisms) use energy from light to synthesise carbohydrates from carbon dioxide and water. Photosynthesis can be shown as:
CO2 + H2O + energy® [CH2O] + O2 plankton. Free-floating, mostly microscopic, aquatic organisms. Plankton can be divided into phytoplankton (plants) and zooplankton (animals). For more information see What is plankton? (Australian Museum Online). respiration. Cellular respiration is the process by which organisms release energy from complex organic molecules, typically sugars. All living things, including plants, respire. Most use oxygen (aerobic respiration) and release carbon dioxide. The balanced chemical equation for aerobic respiration is sources and sinks. A source is the place or compartment from which a substance comes while a sink is the place or process that takes the substance out of circulation. For example, young growing forests are a carbon sink, while the burning of fossil fuels is a carbon source.
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