Quantification of greenhouse gas emissions in Thessaloniki

Large cities and urban areas are major contributors to methane and carbon-dioxide emissions. Official emission inventories are mostly based on a bottom-up approach where the emissions are derived from activity data, e.g. fossil fuel burning. Differences in the reporting processes in different countries lead to high uncertainties in the official inventories.
The COllaborative Carbon Column Network (COCCON) measures greenhouse gases using ground-based remote sensing. In particular, portable Fourier transform infrared spectrometers EM27/SUN are used, which were developed at KIT in cooperation with Bruker. Both stationary measurements over longer periods of time as well as time-limited measurement campaigns with several instruments are performed. In the measurement campaigns, the emissions of selected cities in Europe have been determined in a top-down approach in order to compare them with the results of the official inventories.
In the presented project, results of a preliminary campaign in Thessaloniki in October 2021 are shown, which will be complemented by a campaign lasting several months in the same location planned for summer 2022.
In order to be able to draw more precise conclusions on emissions from the measured volume mixing ratio data, the distribution and dispersion of greenhouse gases will be simulated with the state-of-the-art weather forecast model ICON and the ART extension for aerosols and reactive trace gases developed at KIT. The aim of the project presented here is to improve the evaluation of the measurement campaigns by linking them more directly with simulations of emissions and transport.