An Agenda for Climate Impacts Science

The report Global Change Impacts in the United States released by the US Global Change Research Program in June 2009 identifies a number of areas in which inadequate information or understanding hampers our ability to estimate likely future climate change and its impacts. In this section of the report, the focus is on those areas of climate science that could contribute most towards advancing our knowledge of climate change impacts and those aspects of climate change responsible for these impacts in order to continue to guide decision making.

The Report identifies the six most important gaps in knowledge and offers some thoughts on how to address those gaps:

1. Expand our understanding of climate change impacts. There is a clear need to increase understanding of how ecosystems, social and economic systems, human health, and the built environment will be affected by climate change in the context of other stresses.

2. Refine ability to project climate change, including extreme events, at local scales. While climate change is a global issue, it has a great deal of regional variability. There is an indisputable need to improve understanding of climate system effects at these smaller scales, because these are often the scales of decision-making in society. This includes advances in modeling capability and observations needed to address local scales and high-impact extreme events.

3. Expand capacity to provide decision makers and the public with relevant information on climate change and its impacts. Significant potential exists in the US to create more comprehensive measurement, archive, and data-access systems that could provide great benefit to society, which requires defining needed information, gathering it, expanding capacity to deliver it, and improving tools by which decision makers use it to best advantage.

4. Improve understanding of thresholds likely to lead to abrupt changes in climate or ecosystems. Potential areas of research include thresholds that could lead to rapid changes in ice-sheet dynamics that could impact future sea-level rise and tipping points in biological systems (including those that may be associated with ocean acidification).

5. Improve understanding of the most effective ways to reduce the rate and magnitude of climate change, as well as unintended consequences of such actions. Research will help to identify the desired mix of mitigation options necessary to control the rate and magnitude of climate change, and to examine possible unintended consequences of mitigation options.

6. Enhance understanding of how society can adapt to climate change. There is currently limited knowledge about the ability of communities, regions, and sectors to adapt to future climate change. It is important to improve understanding of how to enhance society's capacity to adapt to a changing climate in the context of other environmental stresses.