MicroCarb aims to compile a global map of sources and sinks of carbon dioxide (CO2), the main greenhouse gas. The microsatellite is planned for launch in 2020.
The mission intends to map our planet’s oceans and forests to ascertain how they function as carbon sinks. At the same time, it will measure how much CO2 is emitted by cities, vegetation and oceans.
Due to the sparse coverage of terrestrial measuring stations in certain regions of the globe, we don’t know what amounts of CO2 are being absorbed and emitted, or how they vary with the seasons.
Such information is nevertheless crucial to understand the origins and impacts of climate change, since CO2 is the main greenhouse gas produced by anthropogenic activities.
To fill this data gap, Japan launched GOSAT in 2009 and NASA OCO-2 in 2014. In 2020, CNES could take over with MicroCarb, which will be carrying a dispersive grating spectrometer designed to measure the CO2 content of the entire atmospheric column with an accuracy on the order of 1 ppm and on the scale of a rectangular pixel 5 km by 6 km.
This spectrometer developed in partnership with French laboratories—the LSCE climate and environmental science laboratory and the Institut Pierre Simon Laplace (IPSL)—will be mounted on a CNES Myriade spacecraft bus.
The new instrument is more compact, almost three times lighter than the OCO-2 spectrometer. The objective is for MicroCarb to detect very local CO2 emissions and combine its measurements with meteorological models.
MicroCarb will fly in a low orbit over the poles and will be solar-powered. Data collected will be shared with the broader scientific community.
The French government is contributing €25 million in funding to the first phase of this project through budgets allocated to the energy transition in its PIA future investment programme.
Other scientific satellite projects to monitor greenhouse gases are already underway. CNES is working on the MERLIN project with the German space agency DLR to measure methane (CH4). MERLIN will use a lidar to fire laser pulses towards the Earth's surface and then analyse the reflected signal to estimate the amount of methane in the atmospheric column. To meet the needs of the Copernicus programme, the European Space Agency (ESA) will also launch the Sentinel-4 and Sentinel-5 satellites no later than 2020 to deliver additional data on the composition of the atmosphere.
On the website of the Ministry of Ecology, Sustainable Development and Energy