Atmospheric Physics and Chemistry Group (APCG)


Ongoing Projects

Inverse modelling of COS and implications for sources and sinks

Jin Ma


Carbonyl sulfide (COS) is a low abundant trace gas that is regarded useful to better constrain gross primary production (GPP), which is the global uptake of CO2 by the biosphere. COS also contributes to stratospheric sulfur aerosols, and thus mitigates climate warming. However, the global sources and sinks of COS remain uncertain. In order to better constrain global sources and sinks of COS, we focus on inverse modelling of the global COS budget, constrained by NOAA ground observation network. We used TM5-4DVAR system to perform inverse modelling and assimilate NOAA observational data. We also did validation of the system against independent data such as HIPPO, NOAA airborne profiles and satellite data sets. In the future, this work will be extended to study the COS-CO2 interactions and with COS S-isotopologues. The research project will inform us about where the potential sources or sinks would be and what could be missing emissions for COS. Potentially, both experimentalists and modellers will benefit from the research. For example, experimentalists will better know where to best measure COS globally, and modellers will also apply new measurement data to better constrain the global budget of COS.