sequestration targets) has raised questions about the human implications and feasibility of reaching these targets.
Discussions at the workshop generated a series of research suggestions (see Box 1) in response to the interests of participants associated with the CCSP. Among the recurring themes in these suggestions were three substantive research needs linking human activities and the carbon cycle:
Need to analyze, test, and improve social assumptions in emissions models and scenarios. Existing models and scenarios are built on unrealistic social assumptions and are not well supported by relevant theory or data. They do not include intelligent agents or represent feedbacks among model elements (e.g., response of human fertility to changing economic conditions and age distributions; response of consumption and income distribution to changes in trade). Analyses of the models could rule out some scenarios as socially impossible or at least allow for estimates of differential likelihood among scenarios. They could also lead to future scenarios based on more realistic assumptions about social processes. Regional-level studies and models can help strengthen understanding of human dimensions of the carbon cycle.
Need for better process understanding of how social and economic forces drive the carbon cycle. Topics mentioned included the driving forces of energy use in developing countries, the sources of “endogenous” technological change, the intended and unintended effects of past policies, and the causes of rapid changes in human activity and lifestyles (e.g., recent worldwide fertility decline; patterns of increasingly consumptive living). Understanding of these processes would be facilitated by good historical records. It may also require developing new indicators—for example, indicators of energy services, distinct from energy consumption, that can facilitate analysis of development paths that decrease the carbon intensity of economic development.
Need for better analyses working backward from policy objectives. These analyses identify the policy and behavioral changes required to achieve a given environmental outcome rather than identifying the environmental outcomes likely to arise as a result of given policy and behavioral changes. They can be used to assess the feasibility of policy targets, including sequestration policies.