Climate change is more commonly associated only to the enhanced greenhouse effect caused by the increasing concentration of greenhouse gases1. Water vapor (H2O), carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), and ozone (O3) are the primary greenhouse gases in the Earth’s atmosphere. Moreover there are a number of entirely human-made greenhouse gases in the atmosphere, such as the halocarbons and other chlorine- and bromine-containing substances, dealt with under the Montreal Protocol. Besides CO2, N2O, and CH4, the Kyoto Protocol deals with the greenhouse gases sulfur hexafluoride (SF6), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs). in the atmosphere. The ultimate objective of the UNFCCC therefore is to achieve, stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. Such a level should be achieved within a time frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner.

Air pollution links with climate change

The Intergovernmental Panel on Climate Change (IPCC) has also identified air pollution (aerosols) as an important factor affecting the climate system. The Third Assessment Report of the IPCC indicates that the aerosols depending on size and composition may cause either positive (warming effect) or negative (cooling effect) radiative climate forcing. Unlike the greenhouse gases, IPCC recognizes that the level of scientific understanding of the effect of aerosols in the atmosphere is still low.

Currently, however, more and more evidence support the knowledge that air pollution, which is greatly influenced by urbanization, is altering regional atmosphere and also causing regional climate change. Concurrently, knowledge on the impacts of climate change in Asia and the rest of the world is likewise increasing.

Co-benefits approach

CAI-Asia recognizes that both climate change and urban air pollution are two important environmental concerns that need urgent attention. CAI-Asia wants to explore the possibility that solutions are available to address both problems together (co-benefits approach). And since both problems have common drivers such as Energy and Transport, opportunity exists to come up with common potential solutions.

The traditional approach to separately address these two problems have already produced positive results but CAI-Asia believes that more can be achieved if the co-benefits approach to UAQM and CC mitigation will be adopted. The co-benefits approach offers a stronger leverage with policy makers that will hopefully lead towards more substantial policies and subsequent investments addressing both problems.

CAI-Asia and climate change

There already exists a large number of initiatives and websites working on climate change. CAI-Asia does not aim to duplicate these efforts. The CAI-Asia’s webpages and activities on climate change will therefore focus only on its aim to support activities that promote the co-benefits approach to urban air quality management and climate change mitigation in Asia. The website will document the studies that relate to the science of climate change and evidence of its impacts especially in Asia, the linkages between air pollution and climate change, the policies that are relevant to Asia (Kyoto Protocol and CDM) and provide resources on co-benefits approach as well as showcase climate change projects that also impact on the air pollution problem.

(Sources: UNFCCC, 1992; IPCC Glossary, 2001; IPCC Third Assessment Report, 2001.)

Footnote:
1 - Water vapor (H2O), carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), and ozone (O3) are the primary greenhouse gases in the Earth’s atmosphere. Moreover there are a number of entirely human-made greenhouse gases in the atmosphere, such as the halocarbons and other chlorine- and bromine-containing substances, dealt with under the Montreal Protocol. Besides CO2, N2O, and CH4, the Kyoto Protocol deals with the greenhouse gases sulfur hexafluoride (SF6), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs).