to quantify in economic terms. The efficiency and efficacy of overlapping systems of governance and management structures to address trade-offs and determine management strategies is also a critical area of research.
Assess vulnerabilities of ecosystems and the benefits society derives from them to climate change. Ecosystems on land and in the ocean, and the services they provide, are key components of the maintenance of environmental functions and human well-being. Climate change affects this maintenance, with potentially significant societal consequences. Identifying critical linkages and feedbacks among changing ecosystems, their services, and human outcomes (e.g., crop yields, water supply) is essential. To do this requires analytical frameworks and methods for assessing vulnerability of coupled human-environment systems, and the ability of the social and environmental components of such systems to adapt to change. Complicating these assessments is the need to address climate change in the context of other changes, such as land use, acid rain, and nitrogen deposition.
Improve observations and modeling. There is a great need for global-scale, long-term, and continuous observations of land and ocean ecosystems and ongoing changes within them. Such observations will enable measures of ecological processes at relatively fine spatial and temporal scales, which are needed both to provide critical inputs to Earth system models and to track gradual and abrupt change in Earth system processes. The development of indicators of ecosystem health and ecosystem vulnerability is also needed as part of an early warning system (see NRC, 2009i). As mentioned earlier, new Earth system models that address multiple drivers and feedbacks from climate-ecosystem interactions are needed, and they will be most effective if linked to climate models that function at regional scales.