Why CarbonSat? Carbon dioxide (CO2) and methane (CH4) are the two most important anthropogenic ("man-made") greenhouse gases responsible for global warming. Despite their importance our knowledge abour their variable natural and anthropogenic sources and sinks has large gaps. An appropriate knowledge about their sources and sinks is a pre-requisite for reliable climate prediction. Satellites can add important missing global information. Currently two satellite instruments are in orbit measuring CO2 and CH4 with high sensitivity down to the Earth's surface where the regional source/sink signal is largest: SCIAMACHY onboard the European ENVISAT satellite and TANSO aboard the Japanese GOSAT satellite. In order to continue the satellite CO2 and CH4 global timeseries after SCIAMACHY and GOSAT, i.e., after 2014, and to deliver important additional information on CO2 and CH4, we propose a new satellite mission: Carbon Monitoring Satellite - CarbonSat.
CarbonSat will measure globally the atmospheric concentrations ("dry-air column-averaged mixing ratios") of CO2 and CH4 with high spatial resolution (2 x 2 km2) and very good spatial coverage (500 km swath width). These atmospheric measurements can be used for inverse modelling of CO2 and CH4 surface fluxes (emissions and uptake, i.e., sources and sinks).
CarbonSat will map - for the first time - the detailed spatial pattern of the CO2 emissions of moderate to strong localized emission sources such as coal-fired power plants (Bovensmann et al., 2010). CarbonSat also has the capability to monitor CO2 emissions of major cities and from strong geological sources such as volcanoes. Similar capabilities exist also for methane which has strong localized emission sources such as large waste disposal sites or fugitive emission from large single oil and gas industrial facilities or clusters. CarbonSat glint observation mode over oceans/water will allow to track for the first time from space not well-characterized strong marine geological CH4 emission sources including large seeps, mud volcanoes or methane releases from the destabilization of shallow marine arctic gas hydrates.
CarbonSat can therefore play an important role in a future monitoring and verification system for anthropogenic greenhouse gas emissions which is needed in the context of international "post-Kyoto/post-Kopenhagen" climate agreements (see, e.g., this National Research Council Report).
The need for CarbonSat type of measurements is underlined in the GEO Carbon Strategy report prepared by the Group on Earth Observations (GEO). GEO has also generated a GEO: Carbon Monitoring Showcase video nicely illustrating the need for global observations of CO2 and CH4. In case of problems to see the video: Goto to youtube and search for "GEO: Carbon Monitoring Showcase" or use this link: http://www.youtube.com/watch?v=cmS3RergtP4 or try this link: carbon_final_Low.mov.
One CarbonSat will significantly advance our understanding of the sources and sinks of CO2 and CH4. There are however limitations. Especially for sources with significant time-dependent emissions it would be advantageous to overfly them more frequently than possible with a single satellite. To improve on this we also think about a "CarbonSat Constellation", i.e., a series of CarbonSats from, for example, several nations.
In this context it is also very important to point out that there are also a number of other activities on-going with the goal to measure greenhouse gases from space in the future. An activity of high relevance in this context are the activities in the US aiming at a rebuild and relaunch of OCO.
If you would like to know more about CarbonSat, please have a look at the CarbonSat Mission Overview (pdf, 0.6 MB) and the additional information given on this web site.
If you would like to know what we have achieved with SCIAMACHY, here the link to our SCIAMACHY carbon gases website.
If you like "movies", here a link to our From SCIAMACHY to CarbonSat animation (wmv, 13.5 MB).