UN agrees on options to mitigate global warming[fr][de] 

The most important findings to emerge from the 4th Assessment Report published on 4 May are found in the Working Group III report entitled 'Mitigation of Climate Change'.  

A number of climate-change response options are presented in the report, along with an assessment of the economic and social impact of mitigation efforts. The reports of the other two Working Groups deal with the scientific basis used to assess climate change, and with the likely impact of climate change on human populations and ecosystems.

• Technologies

The role of technologies in mitigating climate change is mentioned several times in connection with various sectors, including buildings, waste and agriculture. "Deployment of a portfolio of technologies that are currently available and those that are expected to be commercialised in coming decades," so the report, would lead to the most favourable results. Initial investments in technologies may produce significant costs, but these decrease over time through efficiency gains.

• Economic potential and costs

There is "substantial economic potential" that can result from GHG mitigation efforts. Costs resulting from mitigation can be offset if, for example, "revenues from carbon taxes or auctioned permits under an emission trading system are used to promote low-carbon technologies or reform of existing taxes". 
The report states that mitigation will have a negative effect on countries' GDP if it is not accompanied by appropriate investments in infrastructure and technologies, in addition to reforms in tax and market structures.

If done correctly, the report claims that keeping the rise in global temperatures to beneath 2 degree centigrade would cost a mere 0.12% of global annual GDP.

• Transport

On a somewhat less encouraging note, the report states that despite a number of options for reducing emissions in the transport sector, "their effect may be counteracted by growth in the sector". Growth in the air transport and vehicle sectors, in other words, may outpace advances in vehicle and airplane fuel efficiency, and the potential of biofuels is still largely dependant production methods. 
The report goes on to say that mitigation in the transport sector must be linked with other measures since a reduction of vehicle emissions "is often a co-benefit of addressing traffic congestion, air quality and energy security".

• Investments in energy infrastructure

Upgrades in energy and other infrastructure are generally seen as a significant GHG mitigating factor, yet the effects of certain upgrades may require decades to take effect. In this light, the report notes that 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".

The use of renewable energies is of course encouraged in the report, but alongside other energy sources including nuclear power.

• Policy instruments

The report presents a mixed picture on the benefits of policy instruments, stating that there are advantages and disadvantages to all systems. Standards and regulations, for example, may provide certainty on allowed emissions levels, but they "may not induce innovations and more advanced technologies". 

• Lifestyle changes

Adjustments in individual lifestyles is also mentioned in the report as a significant GHG mitigating factor.

Environment Commissioner Stavros Dimas praised the IPCC's conclusions for fully supporting "the EU’s view that developed countries must reduce emissions to 30% below 1990 levels by 2020," a reflection of the EU's independent commitment made in January 2007.

Catherine Pearce, climate campaigner for Friends of the Earth (FOE), believes the IPCC report presents "further clear evidence that should compel governments to immediate action". FOE also argues that, beyond technological innovations, a "range of mitigation efforts are required, including changes in lifestyle and unsustainable consumption patterns in the rich, developed countries".

The report was also praised by Europe's nuclear energy industry. FORATOM, the trade association that represents the industry. FORATOM welcomed the inclusion of nuclear energy as part of the energy mix recommended for mitigating GHG emissions.

A more critical view of the report was taken by the Greens in the European Parliament, who charged that the report is "unfortunately very conservative in its findings," and that it does not take into account the "necessary lifestyle changes" required to tackle climate change.

Strong criticism also came from several environmental groups, including Biofuelwatch and the Global Forest Coalition, for the report's "recommendation for large-scale expansion of biofuels from monocultures, including from GM crops, even though monoculture expansion is a driving force behind the destruction of rainforests and other carbon sinks and reservoirs, thus accelerating climate change. "