1Institute of Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany
2Karlsruhe Institute of Technology, Institute for Meteorology and Climate Research, Karlsruhe, Germany
3Finnish Meteorological Institute, Helsinki, Finland
4Department of Physics, University of Toronto, Toronto, Canada
5Institute for Space and Atmospheric Studies, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
6Department of Chemistry, University of York, York, UK
7Chalmers University of Technology, Department of Earth and Space Sciences, 41296 Gothenburg, Sweden
8Department of Chemistry & Biochemistry, Old Dominion University, Norfolk, VA, USA
Received: 16 Feb 2015 – Discussion started: 10 Apr 2015
Abstract. As part of European Space Agency's (ESA) climate change initiative, high vertical resolution ozone profiles from three instruments all aboard ESA's Envisat (GOMOS, MIPAS, SCIAMACHY) and ESA's third party missions (OSIRIS, SMR, ACE-FTS) are to be combined in order to create an essential climate variable data record for the last decade. A prerequisite before combining data is the examination of differences and drifts between the data sets. In this paper, we present a detailed analysis of ozone profile differences based on pairwise collocated measurements, including the evolution of the differences with time. Such a diagnosis is helpful to identify strengths and weaknesses of each data set that may vary in time and introduce uncertainties in long-term trend estimates. The analysis reveals that the relative drift between the sensors is not statistically significant for most pairs of instruments. The relative drift values can be used to estimate the added uncertainty in physical trends. The added drift uncertainty is estimated at about 3 % decade−1 (1σ). Larger differences and variability in the differences are found in the lowermost stratosphere (below 20 km) and in the mesosphere.
Revised: 29 Sep 2015 – Accepted: 30 Sep 2015 – Published: 16 Oct 2015
Rahpoe, N., Weber, M., Rozanov, A. V., Weigel, K., Bovensmann, H., Burrows, J. P., Laeng, A., Stiller, G., von Clarmann, T., Kyrölä, E., Sofieva, V. F., Tamminen, J., Walker, K., Degenstein, D., Bourassa, A. E., Hargreaves, R., Bernath, P., Urban, J., and Murtagh, D. P.: Relative drifts and biases between six ozone limb satellite measurements from the last decade, Atmos. Meas. Tech., 8, 4369-4381, doi:10.5194/amt-8-4369-2015, 2015.