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Newsflash
Reading, 10/12/2019

The Copernicus Atmosphere Monitoring Service (CAMS), implemented by the European Centre for Medium-Range Weather Forecasts on behalf of the European Union, has announced exciting new developments for their global carbon dioxide surface flux maps.

The newly released dataset makes use of satellite data to estimate CO2 surface sources and sinks. It benefits from a much more extensive observational coverage and has the capacity of being updated much more rapidly than the fluxes relying on ground-based observations, which corresponds to current state-of-the-art. These new CO2 data are now freely available on the CAMS website, along with the corresponding data obtained from ground-based observations.

CO2 is the main greenhouse gas emitted through human activities and therefore a primary driver for climate change. In 2018, more than 10 billion tonnes of carbon were released into the Earth’s atmosphere by the combustion of fossil fuels and the atmospheric concentration of the greenhouse gas is increasing at an average rate of 0.5% per year*. At the same time, CO2 is naturally exchanged between the Earth’s surface and the atmosphere through CO2 sinks, such as oceans and photosynthesis by plants, and CO2 sources such as the respiration of vegetation. It is now more important than ever before that accurate information about levels of the gas in our atmosphere and the origins of its sources and sinks.

The Laboratory for Sciences of Climate and Environment (LSCE) in France, which provides the CAMS greenhouse-gas fluxes, has worked in partnership with scientists from NASA’s OCO-2 (Orbiting Carbon Observatory 2) science team to carry out much-needed research to use satellite observations for a better understanding of the full carbon cycle.**

Thanks to the quality of observations from the OCO-2 satellite instrument and of the advanced inverse modelling system used, the new system is state-of-the-art. While different in some cases, these new satellite observations-based CO2 maps are for the first time of equal quality to the reference surface observations-based product in comparison with independent data. This breakthrough means that the two datasets provided by CAMS act in a complementary way with one another, giving additional insights into the mechanisms underlying carbon sources and sinks, drivers of climate change. These products will also help governments to closely monitor effective progress towards the objectives set out in the 2015 Paris Climate Agreement.

Jean-Noël Thépaut, Director of ECMWF Copernicus comments: “This achievement is a key stepping stone for the efforts we lead at ECMWF on behalf of the European Commission to support the development of a global monitoring and verification support capacity of the carbon cycle and carbon emissions. I’m pleased that we can now look forward to the prospect of Europe’s capacity in this area, and the commitment made at the recent ESA Ministerial Council was another major step.”

Frédéric Chevallier from the Laboratory for Sciences of Climate and Environment (LSCE), who led the research, comments: “Surface measurements of CO2 tend to sample the lowest part of the atmosphere with high accuracy. However, they are mostly located in easily accessible regions of developed countries. Satellite observations of CO2 are less accurate but cover most of the globe. Higher quality data gained by satellites to match those obtained via surface monitoring will introduce new benefits including enabling us to provide robust carbon flux estimates for large countries to help them monitor their impact on the climate.”

Richard Engelen, Deputy Director of the Copernicus Atmosphere Monitoring Service, adds: “In the coming years it is going to be increasingly important that we can accurately monitor the levels of CO2 in our atmosphere with satellites to monitor and understand the natural carbon cycle as well as human-induced emissions. The team at LSCE in partnership with the OCO-2 science team have worked incredibly hard on our behalf to develop ways to strengthen our carbon dioxide monitoring activities and we are excited about the newly released products.”

* More information on the effect of greenhouse gases including CO2 is available via the Copernicus Climate Change Service (C3S) website.

** The study has just been published: Chevallier, F., Remaud, M., O'Dell, C. W., Baker, D., Peylin, P., and Cozic, A.: Objective evaluation of surface- and satellite-driven carbon dioxide atmospheric inversions, Atmos. Chem. Phys., 19, 14233–14251, https://doi.org/10.5194/acp-19-14233-2019, 2019.