May 14, 2007

Technologies, policies exist to stabilize GHGs, mitigate climate change, says IPCC report

Following up on its report earlier this year discussing the link between human activity and climate change (EcoWeek February 5, 2007), Working Group III of the Intergovernmental Panel on Climate Change (IPCC) has outlined an extensive range of practical and policy options for mitigating the impacts of climate change and for slowing, if not halting, the rise in greenhouse gas (GHG) emissions worldwide.

Although the Kyoto Protocol is forecast to have a limited impact on global GHG emissions during its first commitment period, the IPCC concludes that the United Nations Framework Convention on Climate Change (UNFCCC) and its Protocol have succeeded in establishing a global response to the climate change problem. Its other achievements have included the stimulation of an array of national policies, creation of an international carbon market and the establishment of new institutional mechanisms that may provide the foundation for future mitigation efforts.

Mitigation of Climate Change, the second volume of the IPCC's forthcoming Fourth Assessment Report (AR4) reviews GHG emission trends and discussions mitigation in the short, medium and long term. The report sets out a full range of technological options for various GHG-emitting sectors, along with policies, measures and instruments to mitigate climate change. The working group takes into account the value of efforts by individuals, through lifestyle modifications, and discusses climate change mitigation in the context of sustainable development. Gaps in knowledge are summarized as well.

Worldwide, says the report, GHG emissions rose by 70% between 1970 and 2004. During this period, a 33% drop in global energy intensity (energy consumed per unit of production) was not enough to counter the combined effect of global growth in income and population: these rose by 77% and 69%, respectively, and are both drivers of increasing energy-related carbon dioxide (CO2) emissions. And while policies addressing energy security and sustainable development, as well as climate change, have been effective in reducing GHG emissions in different sectors and many countries, the scale of such measures has not yet been large enough to counteract the global growth in emissions.

CO2, primarily from fossil fuel use, remains the largest contributor to GHG emissions, followed by methane, nitrogen oxides and ozone-depleting substances (ODS). The Montreal Protocol is credited with a significant reduction in ODS emissions since the 1990s. By 2004, these emissions had declined to about 20% of their 1990 level.

Over the next few decades, says the Working Group, current climate change mitigation policies and related sustainable development practices will not be enough to prevent a continued global increase in GHG emissions.

Non-mitigation scenarios developed by the IPCC Special Report on Emission Scenarios (SRES) project a 25 to 90% increase in baseline global GHG emissions between 2000 and 2030 (9.7 to 36.7 gigatonnes of CO2 equivalent [CO2e]). In these scenarios, fossil fuels are projected to maintain their dominant position in the global energy mix to 2030 and beyond. Consequently, CO2 emissions from energy use are projected to increase by 45 to 110% during that period.

Both bottom-up and top-down studies indicate that there is substantial economic potential for the mitigation of global GHG emissions over the coming decades, that could offset the projected growth of global emissions or reduce emissions below current levels.

No single sector or technology can address the entire mitigation challenge. All sectors and regions have the potential to contribute to overall mitigation. The leading sectors with available technologies and practices (as well as those expected to be available by 2030) include energy supply, transportation, buildings, industry, forestry, agriculture and waste. The costs of mitigation should be much lower if a multi-gas approach is adopted and carbon sinks are included, rather than focusing on CO2 emission abatement only, says the report.

In industry, management tools that include staff training, reward systems, regular feedback and documentation of existing practices can help overcome industrial organizational barriers and reduce energy use and GHG emissions. The economic potential in the industrial sector is predominantly located in energy-intensive industries.

Full use of available mitigation options is not being made in either industrialized or developing nations, however, says the report. Many industrial facilities in developing countries are new and include the latest technology with the lowest specific emissions. But many older, inefficient facilities remain in both industrialized and developing countries. Upgrading these facilities can deliver significant emission reductions.

The report lists several other key barriers to the full use of available mitigation options by companies. These include: the slow rate of capital stock turnover, lack of financial and technical resources, and limitations in the ability of firms, particularly small and medium-sized enterprises (SMEs), to access and absorb technological information.

Future energy infrastructure investment decisions, expected to total over $20 trillion (U.S.) between now and 2030, will have long-term impacts on GHG emissions because of the long lifetimes of energy plants and other infrastructure capital stock. The widespread diffusion of low-carbon technologies may take many decades, even if early investments in these technologies are made attractive. Initial estimates show that returning global energy-related CO2 emissions to 2005 levels by 2030 would require a large shift in the pattern of investment, although the net additional investment required ranges from negligible to 5-10%.

It is often more cost-effective to invest in end-use energy efficiency improvement than in increasing energy supply to satisfy demand for energy services. Efficiency improvement has a positive effect on energy security, local and regional air pollution abatement, and employment. Education and training programs can help overcome barriers to the market acceptance of energy efficiency, particularly in combination with other measures.

Renewable energy generally has a positive effect on energy security, employment and on air quality. Given costs relative to other supply options, renewable electricity, which accounted for 18% of the electricity supply in 2005, can have a 30-35% share of the total electricity supply in 2030 at carbon prices of up to $50 (U.S.) per tonne of CO2e.

Nuclear power, which accounted for 16% of the electricity supply in 2005, could have an 18% share of the total electricity supply in 2030 at carbon prices up to $50 (U.S.) per tonne of CO2e, but safety, weapons proliferation and waste remain as constraints.

Carbon capture and storage (CCS) in underground geological formations is a new technology with the potential to make an important contribution to mitigation by 2030. Technical, economic and regulatory developments will affect the actual contribution.

Transportation demand management, which includes urban planning (that can reduce the demand for travel) and provision of information and educational techniques (that can reduce car usage and lead to an efficient driving style) can also support GHG mitigation.

Changes in lifestyle and consumption patterns can contribute to climate change mitigation across all sectors. Changes that emphasize resource conservation can contribute to developing a low-carbon economy that is both equitable and sustainable. Changes in occupant behaviour, cultural patterns and consumer choice and use of technologies can result in considerable reduction in CO2 emissions related to energy use in buildings.

Forest-related mitigation activities can considerably reduce emissions from sources and increase CO2 removals by sinks at low cost. Moreover, these can be designed and implemented to be compatible with adaptation and sustainable development, and can have substantial co-benefits in terms of employment, income generation, biodiversity and watershed conservation, renewable energy supply and poverty alleviation.

About 65% of the total mitigation potential is located in the tropics and about 50% of the total could be achieved by reducing emissions from deforestation. Climate change can affect the mitigation potential of the forest sector (i.e., native and planted forests) and is expected to be different for different regions and sub-regions, both in magnitude and direction.

Regarding mitigation in the long term (i.e. after 2030), the Working Group says that in order to stabilize the concentration of GHGs in the atmosphere, emissions would need to peak and decline thereafter. The lower the stabilization level, the more quickly this peak and decline would need to occur. Stabilization at lower concentrations would advance the date when emissions need to peak and would require greater emissions reductions by 2050. Mitigation efforts over the next two to three decades will have a large impact on opportunities to achieve lower stabilization levels.

The range of stabilization levels assessed can be achieved using technologies that are currently available and those that are expected to be commercialized in coming decades. The contribution of different technologies to emission reductions required for stabilization will vary over time, region and stabilization level.

A review of diverse scenarios indicates that energy efficiency plays a key role for most regions and timescales. For lower stabilization levels, scenarios put more emphasis on the use of low-carbon energy sources, such as renewable energy and nuclear power, and the use of CO2 capture and storage (CCS). In these scenarios improvements of carbon intensity of energy supply and the whole economy need to be much faster than in the past.

Including non-CO2 and CO2 land-use and forestry mitigation options provides greater flexibility and cost-effectiveness for achieving stabilization. Modern bioenergy could contribute substantially to the share of renewable energy in the mitigation portfolio.

Governments have a wide variety of policies and instruments they can draw upon to create the incentives for mitigation action. Each comes with its own advantages and drawbacks, but their applicability depends on national circumstances and an understanding of their interactions, says the report.

In general, integrating climate policies in broader development policies makes implementation and overcoming barriers easier. Regulations and standards generally provide some certainty about emission levels, but they may not induce innovations and more advanced technologies.

Financial incentives (subsidies and tax credits) are frequently used by governments to stimulate the development and diffusion of new technologies. While economic costs are generally higher than for the instruments listed above, they are often critical to overcome barriers.

Taxes and charges can set a price for carbon, but cannot guarantee a particular level of emissions. Tradable permits will establish a carbon price. The volume of allowed emissions determines their environmental effectiveness, while the allocation of permits has distributional consequences. Fluctuation in the price of carbon makes it difficult to estimate the total cost of complying with emission permits.

Voluntary agreements between industry and governments are politically attractive, but most have not achieved significant emissions reductions beyond business as usual. However, some recent agreements, in a few countries, have accelerated the application of best available technology and led to measurable emission reductions.

Addressing climate change can be considered an integral element of sustainable development policies. Making development more sustainable by changing development paths can make a major contribution to climate change mitigation, but implementation may require resources to overcome multiple barriers. There is a growing understanding of the possibility of choosing and implementing mitigation options in several sectors to realize synergies and avoid conflicts with other dimensions of sustainable development

Irrespective of the scale of mitigation measures, however, adaptation measures are still necessary. Synergies between mitigation and adaptation can exist, for example properly designed biomass production, formation of protected areas, land management, energy use in buildings and forestry. In other situations, there may be trade-offs, such as increased GHG emissions due to increased consumption of energy related to adaptive responses.

A summary of the report for policymakers may be viewed on the IPCC Web site,

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