Since the pre-industrial era, atmospheric concentration of carbon dioxide (CO2) has increased by 40 % and that of methane (CH4) by 150 % and, since 1980, nitrous oxide (N2O) levels have leapt by 20 %. These greenhouse gases (GHG) are the cause of rapid climate change, the harmful consequences of which are becoming every day more apparent.
Many stakeholders – companies, regions or States – are committed to reducing their GHG emissions in order to combat global warming. To assess the scale of their efforts, precise estimates of these emissions are needed, at various geographical scales and over various time-frames. These must be based on transparent and traceable methods compliant with international standards.
Climate expertise at CEA-LSCE
The Climate Science and Environment Laboratory (LSCE), a joint CEA, CNRS and UVSQ laboratory, is coordinating the VERIFY project as a whole. Its researchers, comprising carbon cycle experts, will provide not only statistical models for combining a range of satellite and in-situ observations to estimate GHG flows, but also the scientific expertise needed to enable VERIFY products to be used for national GHG mitigation policies.
Measurement station for greenhouse gases installed on the CEA Saclay campus, as part of the Icos network. © F.Rhodes/CEA
Drawing up more accurate inventories
The European Union addresses the need of precise GHG estimate with the VERIFY project, a wide-ranging international collaboration (38 partners) via the VERIFY project. Using independent observations, it aims to quantify the carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes as accurately as possible, along with carbon stocks in the atmosphere and terrestrial ecosystems.
A key point is to separate the natural from the man-made components of these flows. VERIFY develops statistical optimisation methods for estimating man-made and natural flows:
- by combining atmospheric transport models with GHG concentration observations obtained by ground-based stations and satellite measurements;
- and by using models and observations of how terrestrial ecosystems work.
“Thanks to a clearer understanding of GHG balances, VERIFY will provide independent national carbon inventories that could be more accurate than those today estimated from statistical sources alone” explains Philippe Peylin (CNRS), the project coordinator. “The mitigation policies defined within the European Union to achieve the objectives of the Paris climate agreement could then be coordinated using a reliable, operational tool”.
At the heart of a web of initiatives
1 The ‘Intergovernmental Panel on Climate Change’, to which CEA also contributes extensively, via the LSCE.
The European VERIFY collaboration interacts closely with the research institutes and the IPCC1 on scientific matters, as well as with the GHG measurement infrastructures. At a European level, it uses the data it receives from the ICOS (Integrated Carbon Observation System) infrastructure and will eventually use data from the Microcarb satellite, scheduled for launch in 2020. It will share its results with the European CHE (CO2 Human Emissions) project, a topic very close to its own, and to which the LSCE researchers contribute.
The “pre-operational” system and basic scientific knowledge developed by VERIFY will naturally be transferred to an operational centre (for example the European Centre for Medium-Range Weather Forecasts in Great Britain). VERIFY will also make its advances available to a range of international projects measuring and monitoring GHG (such as the Global Carbon Project) resulting from the United Nations Future Earth programme, and the World Meteorological Organisation.
About VERIFY
Launched in February 2018, VERIFY is bringing together 38 different partners from 12 European countries over a two-year period. Having received EU funding of 10 million euros, the project will contribute to deliver policy-relevant information to track progress of the EU mitigation efforts to meet the targets of the Paris Agreement on Climate.