Carbon cycle research is often carried out in isolation from research on energy systems and normally focuses only on the biophysical patterns and processes of carbon sources and sinks. The Global Carbon Project represents a significant advance beyond the status quo in several important ways. First, the problem is conceptualised from the outset as one involving fully integrated human and natural components; the emphasis is on the carbon-climate-human system (fossil-fuel based energy systems + biophysical carbon cycle + physical climate system) and not simply on the biophysical carbon cycle alone. Secondly, the development of new methodologies for analysing and modelling the integrated carbon cycle is a central feature of the project. Thirdly, the project provides an internally consistent framework for the coordination and integration of the many national and regional carbon cycle research programmes that are being established around the world. Fourthly, the project addresses questions of direct policy relevance, such as the management strategies and sustainable regional development pathways required to achieve stabilisation of carbon dioxide in the atmosphere. Finally, the Global Carbon Project goes beyond the traditional set of stakeholders for a global change research project by seeking to engage the industrial and energy sectors as well as the economic development and resource management sectors in the developing regions of the world.
The global carbon cycle is of intense interest to policy-makers, the scientific community, and public organizations. As a result, numerous new programmes and projects have been developed over the last few years. TCO and GCP are two such complementary initiatives which share a common goal of advancing the availability of more accurate and mutually consistent estimates of terrestrial carbon sources, sinks and processes, regionally and globally, through syntheses of observations and models. The workshop was intended to advance the availability of more accurate and mutually consistent estimates of the distribution of carbon sources and sinks at a regional and global level. This goal can be achieved by convergence of in situ and satellite observations, experiments and modelling strategies; improvements in data acquisition and sharing; and product generation, distribution and use. The workshop focused on the following questions and associated issues: 1. What carbon cycle data products could be routinely produced from a carbon observation system based on model-data and model-data fusion? 2. What are the main conceptual approaches to assimilating atmospheric carbon content, terrestrial carbon flux and remotely sensed data into coupled atmospheric circulation-carbon cycle models? 3. What is the present and eventual uncertainty regarding the main carbon fluxes at global and regional scale, and how will it be reduced by projects currently underway and about to begin? 4. In what regions, and on what topics, will new data inputs make the largest contribution to reducing the residual uncertainties? What actions should be taken to overcome the gaps and limitations identified?