Mitigation of global warming
From Emissions Wiki
Mitigation of global warming involves taking actions aimed at reducing the extent or likelihood of global warming. This is in contrast to Adaptation to global warming which involves taking action to take advantage of the positive effects of global warming while preventing or minimizing the negative effects of global warming.
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Energy efficiency and conservation
Main article: Energy conservation
Energy which is saved by improvements in efficiency has, in practice, often provided good environmental benefit and provided a net cost saving to the energy user. Building insulation, fluorescent lighting, and public transportation are some of the most effective means of conserving energy, and by extension, the environment. However, Jevons paradox poses a challenge to the goal of reducing overall energy use (and thus environmental impact) by energy conservation methods.
Transport
The development of new technologies, such as electric cars (and hybrids), and hydrogen cars, may reduce the consumption of oil and emissions of carbon dioxide. However, this does depend on the way the required electricity is generated, so these technologies need to be complemented by low-carbon-dioxide sources of electricity.
More mundanely, CO2 emissions standards may be applied to conventional vehicles, and effective urban planning and public transport can also reduce greenhouse gas emissions per passenger kilometer. Biofuels such as biodiesel are also a possibility.
Housing and urban planning
As well as designing buildings which are more energy efficient also suggested for hotter climates is the possibility of using lighter-coloured, more reflective materials in the development of urban areas (e.g. by painting roofs white) and planting trees [1], [2]. This saves energy because it cools buildings and reduces the urban heat island effect thus reducing the use of air conditioning. In cold climates where air conditioning accounts for only a small proportion of energy consumption, the opposite of this approach may be preferable: An increase in average city temperatures by painting roofs black decreases demand for heating fuel.
Urban planning also has an effect on energy use. Approaches such as New Urbanism and Transit-oriented development seek to reduce distances travelled, especially by private vehicles, encourage public transit and make walking and cycling more attractive options. This is achieved through medium-density, mixed-use planning and the concentration of housing within walking distance of town centers and transport nodes.
Alternative energy sources
Renewable energy
Main articles: Renewable energy and Renewable energy development
One means of reducing carbon emissions is the development of new technologies such as renewable energy. Most forms of renewable energy generate no appreciable amounts of greenhouse gases except for biofuels derived from biomass.
Solar Power
Main articles: Solar Power
Advantages
- Solar power is pollution free during use. Production end wastes and emissions are manageable using existing pollution controls. Enhanced decommisioning end recycling technologies are under development. <ref>Environmental Aspects of PV Power Systems</ref>
- Once facilities have been constructed they run with little extra input or maintenance.
Disadvantages
Solar power at the Earth's surface, has a number of disadvantages which must be addressed as engineering problems to make it an effective source of energy supply:
- It is only available in abundance in certain areas of favourable climate and latitude. That is, areas near the tropics and which are relatively cloud free.
- It is not available at night and is reduced when there is cloud cover.
- It must be converted into some other form of energy to be stored for times when it is not available or to drive transport.
Wind power
Main article: Wind power
Wind power is the only renewable form of energy which is a direct mitigation, drawing energy directly from the atmosphere. A wind turbine produces more than fifty times as much energy over its lifetime as is consumed by its construction and installation.[3]
Although commercial wind power was born in California in the 1980s, in 2004 nine of the ten leading wind turbine manufacturers were based in Denmark, Germany and Spain.
Biofuels
Biofuels include organic matter that is continuously produced and renewable (unlike fossil fuels which form much more slowly) such as slurry or plants or their derivatives. Methane can be extracted from animal slurry and used for energy and ethanol can be received from the anaerobic breakdown of certain plants. Both, although they both produce some carbon dioxide, are much more environmentally friendly than traditional fossil fuels and in a market of rising oil prices will soon be much cheaper. Slurry (often from cows and cattle) is used worldwide in generators. Ethanol is very often used as car fuel in South America now, mixed with petrol to make gasohol. This is better for the environment than fossil fuels however less effective than other completely non-polluting energy sources such as wind power.
Biofuels even today are a major energy source in many developing countries (namely in South America).
Renewable Energy in the European Union
The countries of the European Union, taken together, constitute the leading world power in the development and application of renewable energies. Promotion of renewable energies plays an important role both in the reduction of the EU dependence on foreign energy imports and in the measures which it must take to combat climate change. However, Germany is the only member of the EU that is on track to achieve the objectives set by the Kyoto protocol on climate change.
The Maastricht Treaty set an objective of promoting stable growth that is also protective of the environment. The Amsterdam Treaty added the principle of sustainable development to the objectives of the EU. Since 1997, the EU has been working towards a having renewable energies supply 12% of total EU energy consumption in 2010.
Nuclear energy
Main articles: Nuclear energy
In some countries (such as the UK and Australia, the latter of which has no commercial nuclear energy) there are also discussions about the future role of nuclear power as a possible alternative to fossil fuels with low carbon emissions. Different life cycle studies of nuclear power have come to wildly different conclusions about their emissions. According to one study (van Leeuwen and Smith 2001-2005)[4], carbon dioxide emissions from nuclear power per kilowatt hour are around 20-40% of those for natural gas-fired power stations and about 4 or 5 times greater than that produced by some renewables. But several others show similar emissions from nuclear power and renewables [5].
One study argues that certain gas cogeneration plants are 3-4 times more cost effective than nuclear power for abating CO2 emissions, if all the heat produced can be used onsite or in a local heating system. However, nuclear power also produces heat which could be used in similar ways. The study found similar costs for windpower and nuclear power if not including external costs (such as back-up power).[6]
Decentralised generation
A variety of technologies permitting decentralised electricity generation may permit the reduction of electricity transmission losses and in some cases higher efficiency. These include small-scale solar and wind generation, and small-scale combined heat and power plants. UK power company Powergen markets a microCHP plant which it says allows a household to save 20% of its CO2 emissions per year (1.5 tons).[7]
Carbon capture and storage
Main article: Carbon Capture and Storage
Carbon capture and storage (CCS) is a plan to mitigate climate change by capturing carbon dioxide (CO2) from large point sources such as power plants and subsequently storing it away safely instead of releasing it into the atmosphere. Technology for capturing of CO2 is already commercially available for large CO2 emitters, such as power plants. Storage of CO2, on the other hand is a relatively untried concept and as yet (2006) no powerplant operates with a full carbon capture and storage system.
Geoengineering
Main article: Planetary engineering
Chapter 28 of the National Academy of Sciences report Policy Implications of Greenhouse Warming: Mitigation, Adaptation, and the Science Base (1992) defined geoengineering as "options that would involve large-scale engineering of our environment in order to combat or counteract the effects of changes in atmospheric chemistry." They evaluated a range of options to try and give preliminary answers to two questions: can these options work and could they be carried out a reasonable cost. They also sought to encourage discussion of a third question - what adverse side effects might there be. The following types of option were examined: reforestation, increasing ocean absorption of carbon dioxide (Carbon sequestration) and screening out some sunlight. NAS also argued "Engineered countermeasures need to be evaluated but should not be implemented without broad understanding of the direct effects and the potential side effects, the ethical issues, and the risks.".
Carbon sequestration
Main article: Carbon sequestration
Carbon sequestration has been proposed as a method of reducing the amount of radiative forcing, though concerns have been expressed about its long-term effects.
Seeding oceans with chalk
For example, there is the possibility of countering acidification of the oceans by dumping (alkaline) chalk in the oceans. This solution engenders its own problems, however - notably the energy needed for the largescale mining and processing required.[8]
Seeding oceans with iron
The so-called Geritol solution to global warming is a carbon sequestration strategy whimsically named for a tonic advertised to treat the effects of iron-poor blood. It is motivated by evidence that seeding the oceans with iron will increase phytoplankton populations, and thereby draw more carbon dioxide from the atmosphere. A report in Nature, 10 October 1996, by K. H. Coale et al, measured the effects of seeding equatorial Pacific waters with iron, finding that 700 grams of CO2 were fixed by the resulting phytoplankton bloom per 1 gram of iron seeded[9]. Given the US EPA's current estimate of 1.2×1013 kg of annual atmospheric CO2 surplus, and the current 2006 market asking price of US$ 35/tonne for 65% iron ore fines, less than US$ 800 million worth of iron ore distributed in the equatorial Pacific annually would suffice to entirely offset surplus carbon emissions.
Opponents of this approach argue that fertilizing the ocean is a dangerous proposition. They argue that it would not be possible to control the areas that are fertilized because the ocean is turbulent. They express concern that this approach would upset the current balance of the entire oceanic food chain. They point out that, considering the immense damage caused by adding nutrients to lakes and ponds, it would be a logical conclusion that adding nutrients to the ocean would also cause environmental damage. They suggest that there is even the possibility that blooms would release more greenhouse gas in the form of methane than it would sequester.Template:Ref
Screening out sunlight
Another class of geoengineering approaches to attempt mitigation involves changing the Earth's albedo (reflectivity), to reflect more heat back out into space: a 0.5% albedo increase would roughly halve the effect of CO2 doubling [10]. Methods which have been proposed could include: releasing dust, sulfuric acid or reflecting micro-balloons into the stratosphere; enhancing low-level clouds [11]; creating a Saturn-like ring of small particles [12], or putting a very large mirror or wire mesh in space (perhaps at the L1 point between the Earth and the Sun)[13]. The cooling effect that volcanic eruptions often have on the climate due to ash particles in the upper atmosphere can be seen as an analogy of how these methods might work.
Governmental and Intergovernmental Action
Kyoto Protocol
Main article: Kyoto Protocol
The primary international agreement on combating climate change is the Kyoto Protocol, which came into force on 16 February 2005. The Kyoto Protocol is an amendment to the United Nations Framework Convention on Climate Change (UNFCCC). Countries that have ratified this protocol have committed to reduce their emissions of carbon dioxide and five other greenhouse gases, or engage in emissions trading if they maintain or increase emissions of these gases.
Encouraging use changes
Carbon emissions trading
Main article: Carbon emissions trading
The European Union Emission Trading Scheme (EU ETS) [14] is the largest multi-national, greenhouse gas emissions trading scheme in the world. It commenced operation on 1 January 2005, and all 25 member states of the European Union participate in the scheme. The scheme has created a new market in carbon dioxide allowances estimated at some Euro 35 billion (US$43 billion) per year.[15] The Chicago Climate Exchange was the first (voluntary) emissions market, and is soon to be followed by Asia's first market (Asia Carbon Exchange). A total of 107 million metric tonnes of carbon dioxide equivalent (tCO2e) have been exchanged through projects in 2004, a 38% increase relative to 2003 (78 Mt CO2e).[16]
Carbon tax
Main Article: Carbon tax
In 1991, Sweden introduced the world's first carbon tax. The UK has had a Climate Change Levy on fossil-fuel-based electricity generation since 2001. Plans for a carbon tax in New Zealand were abandoned after the 2005 elections.
Non-governmental approaches
Legal action
In some countries, those affected by climate change may be able to sue major producers, in a parallel to the lawsuits against tobacco companies.[17] Although proving that particular weather events are due specifically to global warming may never be possible (Edward Lorenz (1982): "Climate is what you expect, weather is what you get"), methodologies have been developed to show the increased risk of such events caused by global warming (Stott et al. 2004).
For a legal action for negligence (or similar) to succeed, "Plaintiffs … must show that, more probably than not, their individual injuries were caused by the risk factor in question, as opposed to any other cause. This has sometimes been translated to a requirement of a relative risk of at least two." (Grossman, Columbia J. of Env. Law, 2003) Another route (though with little legal bite) is the World Heritage Convention, if it can be shown that climate change is affecting World Heritage Sites like Mount Everest.[18]
Legal action has also been taken to try to force the U.S. Environmental Protection Agency to regulate greenhouse gas emissions under the Clean Air Act,[19] and against the Export-Import Bank and OPIC for failing to assess environmental impacts (including global warming impacts) under NEPA.[20]
According to a 2004 study commissioned by Friends of the Earth, ExxonMobil and its predecessors caused 4.7 to 5.3 percent of the world's man-made carbon dioxide emissions between 1882 and 2002. The group suggested that such studies could form the basis for eventual legal action.[21]
Personal choices
While many of the proposed methods of mitigating global warming require governmental funding, legislation and regulatory action, individuals and businesses can also play a part in the mitigation effort. Some environmentalist groups encourage individual action against global warming, often aimed at the consumer. Common recommendations include turning off unused devices, using a fuel efiicient car, supporting carbon-free energy sources, and various others. A list of some common recommendations is available here.
Business Opportunities and Risks
In addition to government action and the personal choices individuals can make, the threat posed by global warming provides business opportunities to be exploited and risks to be mitigated.
There has also been business action on climate change.
On 9 May 2005 Jeff Immelt, the chief executive of General Electric (GE), announced plans to reduce GE's global warming related emissions by one percent by 2012. "GE said that given its projected growth, those emissions would have risen by 40 percent without such action." [22]
On 21 June 2005 a group of leading airlines, airports and aerospace manufacturers pledged to work together to reduce the negative environmental impact of the aviation industry, including limiting the impact of air travel on climate change by improving fuel efficiency and reducing carbon dioxide emissions of new aircraft by fifty percent per seat kilometre by 2020 from 2000 levels. The group aims to develop a common reporting system for carbon dioxide emissions per aircraft by the end of 2005, and pressed for the early inclusion of aviation in the European Union's carbon emission trading scheme.[23]
Mitigation in developing countries
Traditionally, economic growth tends to increase pollution as well as greenhouse gas emissions. In order to reconcile economic development with mitigating carbon emissions, developing countries need particular support, both financial and technical. One of the means of achieving this is the Kyoto Protocol's Clean Development Mechanism (CDM). The World Bank's Prototype Carbon Fund is a public private partnership that operates within the CDM.
In July 2005 the U.S., China, India, Australia, as well as Japan and South Korea, agreed the Asia-Pacific Partnership for Clean Development and Climate. The pact aims to encourage technological development that may mitigate global warming, without coordinated emissions targets. The highest goal of the pact is to find and promote new technology that aid both growth and a cleaner environment simultaneously. An example is the Methane to Markets initiative which reduces methane emissions into the atmosphere by capturing the gas and using it for growth enhancing clean energy generation.[24] Critics have raised concerns that the pact undermines the Kyoto Protocol. [25]
However, none of these initiative suggest quantitative cap on the emission from developing countries. This is considered as particularly difficult policy proposal as the economic growth of developing countries are proportionally reflected in the growth of greenhouse emission. Critics of mitigation often argue that, the developing coutries' drive to attain comparable living standard to the developed countries would doom the attempt at mitigation of global warming. Critics also argue that holding down emissions would shift the human cost of global warming from a general one to one that was borne most heavily by the poorest populations on the planet.
July 2006: United States Congress, hitherto a staunch defender of the Nuclear Non-Proliferation Treaty and all it stands for, is poised to allow America's laws to be amended to accommodate civilian nuclear trade with India, despite that country's bomb-building. The Bush administration defends its India deal as good for combating Global warming, good for friendship with the world's biggest democracy and good for jobs in America.
