Current systematic carbon-cycle observations and the need for implementing a policy-relevant carbon observing system

• Published in: Biogeosciences
• Main Authors: Ciais, P., Dolman, A., Bombelli, A., Duren, R., Peregon, A., Rayner, P., Miller, C., Gobron, N., Kinderman, G., Marland, G., Gruber, N., Chevallier, F., Andres, R., Balsamo, G., Bopp, L., Br´eon, F., Broquet, G., Dargaville, R., Battin, T., Borges, A., Bovensmann, H., Buchwitz, M., Butler, J., Canadell, J., Cook, R., DeFries, R., Engelen, R., Gurney, K., Heinze, C., Heimann, M., Held, A., Henry, M., Law, B., Luyssaert, S., Miller, J., Moriyama, T., Moulin, C., Myneni, R., Nussli, C., Obersteiner, M., Ojima, D., Pan, Y., Paris, J., Piao, S., Poulter, B., Plummer, S., Quegan, S., Raymond, P., Reichstein, M., Rivier, L., Sabine, C., Schimel, D., Tarasova, O., Valentini, R., Wang, R., van der Werf, G., Wickland, D., Williams, M., Zehner, C.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2014
• Subjects: Arctic
• Online Access: http://hdl.handle.net/11858/00-001M-0000-0014-4CA4-0; http://hdl.handle.net/11858/00-001M-0000-0014-4CA6-C; http://hdl.handle.net/11858/00-001M-0000-0019-DAEF-1

A globally integrated carbon observation and analysis system is needed to improve the fundamental understanding of the global carbon cycle, to improve our ability to project future changes, and to verify the effectiveness of policies aiming to reduce greenhouse gas emissions and increase carbon sequestration. Building an integrated carbon observation system requires transformational advances from the existing sparse, exploratory framework towards a dense, robust, and sustained system in all components: anthropogenic emissions, the atmosphere, the ocean, and the terrestrial biosphere. The goal of this study is to identify the current state of carbon observations and needs for a global integrated carbon observation system that can be built in the next decade. A key conclusion is the substantial expansion (by several orders of magnitude) of the ground-based observation networks required to reach the high spatial resolution for CO2 and CH4 fluxes, and for carbon stocks for addressing policy relevant objectives, and attributing flux changes to underlying processes in each region. In order to establish flux and stock diagnostics over remote areas such as the southern oceans, tropical forests and the Arctic, in situ observations will have to be complemented with remote- sensing measurements. Remote sensing offers the advantage of dense spatial coverage and frequent revisit. A key challenge is to bring remote sensing measurements to a level of long-term consistency and accuracy so that they can be efficiently combined in models to reduce uncertainties, in synergy with ground-based data. Bringing tight observational constraints on fossil fuel and land use change emissions will be the biggest challenge for deployment of a policy-relevant integrated carbon observation system. This will require in-situ and remotely sensed data at much higher resolution and density than currently achieved for natural fluxes, although over a small land area (cities, industrial sites, power plants), as well as the inclusion of fossil fuel CO2 ...