Heidelberg 2015 – wissenschaftliches Programm
UP 13.1: Poster
Donnerstag, 26. März 2015, 10:45–19:45, G/Foyer
Evaluation of GOME2 tandem observations of NO2 — •Andreas Richter, Andreas Hilboll, Lisa K. Behrens, and John P. Burrows — Institute of Environmental Physics, University of Bremen, Bremen, Germany
Observations of atmospheric NO2 columns from satellite have proven to provide useful information for both tropospheric and stratospheric atmospheric chemistry studies.
Since the launch of the second GOME2 instrument on MetOp-B in September 2012, two nearly identical instruments observe atmospheric NO2 with just half an orbit (45 min) separation. After an initial phase of operation with the same swath width (1920 km) and some test configurations, the GOME2 instrument on MetOp-A was switched to a narrower swath in July 2013. This resulted in smaller ground pixels (40× 40 km2 instead of 80 × 40 km2) while still conserving some spatial overlap with the measurements of GOME2 on MetOp-B.
This unique data set of parallel measurements provides an opportunity to investigate different aspects of the NO2 retrieval from satellite data: The consistency between observations from two instruments, the impact of viewing geometry, the importance of spatial resolution, and the influence of clouds and their retrieval from the two data sets.
The overall result of the comparisons shows very good consistency between the two data sets with higher local values at better spatial resolution as expected, an important result for combined use of the two data sets. However, the analysis also reveals systematic differences which will be discussed in detail.