Harmonisation of sixteen tropospheric ozone satellite data records

作者：Arno Keppens, Daan Hubert, J. Granville, Oindrila Nath, Jean‐Christopher Lambert, Catherine Wespes, Pierre‐François Coheur, Cathy Clerbaux, Anne Boynard, Richard Siddans, Barry G. Latter, Brian J. Kerridge, Serena Di Pede, Pepijn Veefkind, Juan Cuesta, G. Dufour, Klaus-Peter Heue, Melanie Coldewey‐Egbers, Diego Loyola, Andrea Orfanoz-Cheuquelaf, Swathi Maratt Satheesan, Kai‐Uwe Eichmann, Alexei Rozanov, Viktoria Sofieva, J. R. Ziemke, Antje Inness, Roeland Van Malderen, Lars Hoffmann · 年份：2025 · DOI：10.5194/egusphere-2024-3746 · 被引用次数：4 · 研究领域：Atmospheric Ozone and Climate、Atmospheric and Environmental Gas Dynamics、Air Quality Monitoring and Forecasting

Abstract. The first Tropospheric Ozone Assessment Report (TOAR, 2014–2019) encountered several observational challenges that limited the confidence in estimates of the burden, short-term variability, and long-term changes of ozone in the free troposphere. One of these challenges is the difficulty to interpret the consistency of satellite measurements obtained with different techniques from multiple sensors, leading to differences in spatiotemporal sampling, vertical smoothing, a-priori information, and uncertainty characterisation. This motivated the Committee on Earth Observation Satellites (CEOS) to initiate a coordinated activity VC-20-01 on improving the assessment and harmonization of tropospheric ozone measured from space. Here, we report on work that contributes to this CEOS activity, as well as to the ongoing second TOAR assessment (TOAR-II, 2020–2025). Our objective is to harmonise the spatiotemporal perspective of (sixteen) satellite ozone data records, thereby accounting as much as possible for differences in vertical smoothing and sampling. Four harmonisation methods are presented to achieve this goal: two for ozone profiles obtained from nadir sounders (UV-visible, IR, and combined UV-IR), and two for tropospheric ozone column products derived by one of the residual methods (Convective Cloud Differential or Limb-Nadir Matching). We discuss to what extent harmonisation may affect assessments of the spatial distribution, seasonal cycle, and long-term changes in fre...