Validation of the TM5 chemistry transport model with MIPAS COS measurements

TM5 COS distributions at 250 hPa for the months June to August 2008 to 2010, from model runs with a priori fluxes (upper left panel), and the model runs S_u (upper right panel) and S1 (lower left panel).  In model run S_u, the spatial distribution of the missing emissions of 432 Gg a^-1 of S equivalents was optimized. In model run S1, biosphere and ocean fluxes were optimized. The lower right panel shows the COS distribution observed by MIPAS at 250 hPa in the months June to August 2002-2011. These comparisons are published in Atmos. Chem. Phys. in the framework of inverse modelling of the global COS distribution within the 4-D variational data-assimilation system of the TM5 chemistry transport model.

There is still considerable lack of information on the sources of the atmospheric constituent carbonyl sulfide (COS). MA et al. for the first time have tackled this problem with an inverse modelling approach, using the 4-Dimensional variational data-assimilation system of the TM5 chemistry transport model (TM5-4DVAR).They found that the missing sources are likely located in the tropical regions. However they can not rule out an overestimated biospheric sink in the tropics as well as extra COS uptake or reduced emissions at high northern latitudes. Among other satellite data, MIPAS COS was used to validate the model results.

For more information see: https://doi.org/10.5194/acp-21-3507-2021