Recent Variations in the Global Carbon Balance Derived with CarbonTracker Europe for 2000-2014

Abstract:

The CarbonTracker Europe data assimilation system (CTE2015) estimates the net biosphere and ocean carbon fluxes using atmospheric observations of CO₂ mole fractions. We will present results from our latest update spanning the 2000-2014 period and discuss the recent variations in the carbon cycle, highlighting especially the first estimates of the carbon fluxes in the year 2014. We will link the sources and sinks of carbon to the observed atmospheric growth rates of CO₂ mole fractions for the different years, with special focus on the year of the highest observed growth rate in the record (2013) and the year with the relatively low growth rate (2014) (www.esrl.noaa.gov/gmd/ccgg/trends/).

The CTE2015 method includes results from the SiBCASA biosphere model, combined with GFED4 burned area estimates to inform on biomass burning carbon emissions. We use estimated fossil fuel emissions based on the recent global total estimates from the Global Carbon Project. Spatial variations are based on a combination of the EDGAR4.2 and IER Stuttgart databases. Atmospheric CO₂ observations are from the recent ObsPack GLOBALVIEWplus product which includes 205 datasets from the global network. The transport model TM5 is used to link the carbon fluxes to the observations. Fluxes are optimized on a gridded horizontal resolution of 1x1 degree for the Northern Hemisphere and on ecoregion scale for the rest of the world.

Our results are an example of an elaborated product (Level 3) of the ICOS Carbon Portal (www.icos-cp.eu). The ICOS Carbon Portal is a platform for data exchange for observational data from the European ICOS in-situ network and associated research data. It is part of the pan-European research infrastructure ICOS.