The Fourth Assessment Report (AR4) of the United Nations Intergovernmental Panel on Climate Change (IPCC) is placing specific importance on assessing the integration of adaptation and mitigation in the field of climate change as well as on the cross cutting theme of sustainable development. In actual fact these three subjects form an important part of a triangle which was also referred to briefly in the Third Assessment Report (TAR). It needs to be borne in mind that human induced climate change is in itself the result of unsustainable growth and development. It is in response to this reality that the United Nations Framework Convention on Climate Change (UN FCCC) was developed and brought into existence in 1992, focusing on the stabilization of the earths atmosphere by limiting the buildup of greenhouse gases (GHGs), which have been increasing rapidly in recent decades. At the same time, climate change itself is likely to have adverse effects on prospects for sustainable development globally. In particular, as the TAR clearly brought out, the impacts of climate change will fall disproportionately upon developing countries and the poorer sections of society in all countries and thereby exacerbate inequities in health status and access to adequate food, clean water and other resources, between the developed and the developing as well as between the rich and the poor.

The impacts of climate change extend to effects on health, agriculture, water resources, coastal areas and various species and ecosystems. For each region of the world each one of these sets of impacts needs careful assessment and policy responses that must be anticipatory and proactive. In coastal areas, for instance, it is essential that zonal regulations be followed effectively to ensure that life and property are not threatened by sea level rise, which would cause dangers through storm surges and cyclones even before submergence becomes a reality in some of these locations. In terms of protecting livelihoods and countering the threat to the poor in any country, initiatives in the management of agriculture and water would be paramount. In fact there is a substantial overlap between these two areas, because well over three quarters of the water used in most nations is utilized for agriculture. With growing water scarcity in different parts of the globe, it is essential that agricultural methods use water resources efficiently, and assign importance to technologies that conserve water. Not only may this involve changes in patterns of crops grown but also the development of new varieties that are drought resistant and able to survive through periods of low rainfall, since a large percentage of farming in the poorest countries of the world is in the nature of rainfed agriculture.

Overall, adaptation to climate change would become an important aspect of shielding the poor from its adverse impacts. Measures required to bring this about generally have long gestation periods and may require construction of infrastructure, which in itself has long lags in creation. Assessments of the possible impacts of climate change, therefore, require collaboration across disciplines involving not only those well versed in the geophysical sciences but also in the social sciences relevant to a comprehensive assessment of the socioeconomic impacts of climate change. Also important in this context would be assessment of likely extreme events, such as the occurrence of floods and droughts and rapid melting of glaciers, which records indicate has become a grave reality in the 20th century and a source of concern for the flow of rivers in future. Addressing the threat of climate change, of course, requires the involvement of developing countries not only in devising and implementing adaptation measures, but also doing whatever is rational and viable in terms of mitigation. In the developed world where adaptation measures have generally not received adequate attention, combining mitigation and adaptation would form a basis for sound policies. In most developed countries there is a range of so-called "no regrets" measures in mitigation of GHG emissions. But such options exist in the developing world as well. Two areas where there would be large local benefits from pursuing an enlightened strategy with low intensity of greenhouse gas emissions would be in the area of transport and the provision of energy for rural areas in the developing world. In the case of transport strengthening the system of railway transportation would have substantial benefits at the local level as well. So also would be the provision of appropriate inter- and intra-city public transport, which could substitute part of the intensification of road transport using private vehicles. In the provision of energy for rural areas, decentralized forms of energy production using renewable resources, such as solar, wind and biomass would have both global as well as local benefits. Creating models of success that are innovative in terms of technology as well as infrastructure development and strengthening institutions can help accelerate progress in this direction.

It needs to be emphasized that research on climate change and efforts to understand some of the scientific, technological and socioeconomic issues involved need much greater attention and higher allocation of resources worldwide and particularly in developing countries. Even though climate change is a global problem, the characterization of impacts at the local level would define solutions and measures that could be adopted for meeting the challenge ahead. Research, development and demonstration of solutions with merit, therefore, require efforts to be stepped up in every nation. Governments at every level, research organizations and academia and civil society need to be informed of the likely causes of neglect in this critical area, and the need for early action on a coordinated basis. A rational approach can be evolved only on the basis of combined treatment of adaptation and mitigation within the framework of strategies for sustainable development. I welcome this special issue as a contribution to the global effort to address various interconnected issues that define a long-term view of the diverse aspects of climate change.

R. K. Pachauri
(The Energy and Resources Institute, Teri, Darbari Seth Block, IHC Complex, Lodhi Road, New Delhi 110003, India
e-mail: pachauri@teri.res.in
R. K. Pachauri
Intergovernmental Panel on Climate Change (IPCC), Geneva, Switzerland

Mitig Adapt Strat Glob Change (2007) 12:643-644 DOI 10.1007/s11027-007-9090-9