QUANTIFY model evaluation of global chemistry models: carbon monoxide

In the EU Integrated project QUANTIFY, Atmospheric Chemistry Models (ACMs) are one of the major tools to improve the understanding of key processes relevant for the effects of different transportation modes, and their representation in global models. The performance of the ACMs has been tested through comparisons with the ETH model evaluation global database for the upper troposphere and lower stratosphere (ETHmeg). The ETHmeg database contains data from numerous measurement campaigns making use of both scientific and commercial aircraft as observation platforms, ozone soundings, and surface data. These data have been processed to support an easy and direct comparison with model output. Since model evaluation focuses on the year 2003, observational data to compare model data with are the SPURT campaign, as well as the commercial aircraft program MOZAIC. The model evaluation indicates a particular problem in the simulation of carbon monoxide. If QUANTIFY emissions inventories are used, models significantly underestimate its tropospheric abundance at middle and subtropical latitudes of the northern hemi-sphere. The problematic and potential causes will be discussed.