U.S. National climate assessment gaps and research needs: overview, the economy and the international context

A number of knowledge gaps and research priorities emerged during the third US National Climate Assessment (NCA3). Several are also gaps in the latest IPCC WG2 report. These omissions reflect major gaps in the underlying research base from which these assessments draw. These include the challenge of estimating the costs and benefits of climate change impacts and responses to climate change and the need for research on climate impacts on important sectors such as manufacturing and services. Climate impacts also need to be assessed within an international context in an increasingly connected and globalized world. Climate change is being experienced not only through changes within a locality but also through the impacts of climate change in other regions connected through trade, prices, and commodity chains, migratory species, human mobility and networked communications. Also under-researched are the connections and tradeoffs between responses to climate change at or across different scales, especially between adaptation and mitigation or between climate responses and other environmental and social policies. This paper discusses some of these research priorities, illustrating their significance through analysis of economic and international connections and case studies of responses to climate change. It also critically reflects on the process of developing research needs as part of the assessment process.