algorithm; atmospheric chemistry; detection method; FTIR spectroscopy; ground-based measurement; heterogeneity; ozone; ozonesonde; stratosphere; time series analysis; trend analysis; uncertainty analysis
Abstract :
[en] Large uncertainties and variability in individual ground-based instrument records limit the detection of statistically significant ozone trends, particularly in the lower stratosphere. Available merging studies are typically performed by latitude bands on satellite-based data records. This study derives correlation-based regional composites of ground-based timeseries towards reducing trend uncertainties. We address fundamental heterogeneities resulting from grouping individually homogenized ground-based datasets to enable robust merging. Uneven temporal and vertical resolutions of five ozone measurement techniques (Ozonesondes, FTIR, Dobson Umkehr, Lidar and Microwave radiometers) are handled by integrating monthly mean ozone profiles in two sets of four independent partial columns. Spatial heterogeneity is resolved by defining coherent regions using the Copernicus Atmosphere Monitoring Service (CAMS) reanalysis. Regional timeseries are merged by the BAyeSian Integrated and Consolidated (BASIC) algorithm, adapted to consider propagated measurement uncertainties and the agreement between individual timeseries by Principal Component Analysis (PCA). Trends for the 2000–2024 period are then estimated by Multiple Linear Regression using the LOTUS model. We compare BASIC with a conventional weighted mean. While the weighted mean fails to capture variability during periods of low instrument consensus, BASIC produces more representative timeseries by robustly handling outliers. Accordingly, for the selected regions, BASIC reduces average uncertainties of the trend estimates by 9.4 % relative to the weighted-mean approach. Our results support positive trends in the upper stratosphere, predominantly negative trends in the middle stratosphere and non-significant trends in the lower stratosphere. This study establishes a consolidated ground-based reference to be used for comparison with global satellite-based ozone trends.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Mirallie, Louis ; Federal Office of Meteorology and Climatology, MeteoSwiss, Payerne, Switzerland ; Institute of Applied Physics, University of Bern, Bern, Switzerland ; Oeschger Center for Climate Change Research, Microwave Physics, University of Bern, Bern, Switzerland
Barras, Eliane Maillard; Federal Office of Meteorology and Climatology, MeteoSwiss, Payerne, Switzerland
Jonas, Caroline; Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Uccle, Belgium
Vigouroux, Corinne; Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Uccle, Belgium
Van Malderen, Roeland ; Royal Meteorological Institute, Uccle, Belgium
Petropavlovskikh, Irina ; Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, United States ; NOAA Global Monitoring Laboratory, Boulder, United States
Godin-Beekmann, Sophie ; LATMOS/IPSL, Sorbonne Université, UVSQ, CNRS, Paris, France
Leblanc, Thierry; Jet Propulsion Laboratory, California Institute of Technology, Wrightwood, United States
Steinbrecht, Wolfgang ; Deutscher Wetterdienst, Hohenpeißenberg, Germany
Vadès, Antoine; Federal Office of Meteorology and Climatology, MeteoSwiss, Payerne, Switzerland
Ruefenacht, Rolf ; Federal Office of Meteorology and Climatology, MeteoSwiss, Payerne, Switzerland
Haefele, Alexander ; Federal Office of Meteorology and Climatology, MeteoSwiss, Payerne, Switzerland
Stober, Gunter ; Institute of Applied Physics, University of Bern, Bern, Switzerland ; Oeschger Center for Climate Change Research, Microwave Physics, University of Bern, Bern, Switzerland
Effertz, Peter ; Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, United States ; NOAA Global Monitoring Laboratory, Boulder, United States
Gröbner, Julian ; Physikalisch-Meteorologisches Observatorium Davos World Radiation Centre, Davos Dorf, Switzerland
Ancellet, Gerard; LATMOS/IPSL, Sorbonne Université, UVSQ, CNRS, Paris, France
Cazorla, María ; Instituto de Investigaciones Atmosféricas, Universidad San Francisco de Quito USFQ, Quito, Ecuador
Duff, Petra; Department of Physics, University of Toronto, Toronto, Canada
Frey, Matthias M.; Institute for Meteorology and Climate Research Atmospheric Trace Gases and Remote Sensing (IMKASF), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Gill, Michael; Met Éireann Valentia Observatory, Cahersiveen, Ireland
Hannigan, James W. ; National Center for Atmospheric Research, Boulder, United States
Jones, Nicholas; University of Wollongong, Wollongong, Australia
Kivi, Rigel ; Space and Earth Observation Centre, Finnish Meteorological Institute, Sodankylä, Finland
Köhler, Raphael ; Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
Kois, Bogumil; Institute of Meteorology and Water Management, National Research Institute (IMGW-PIB), Poland
Kollonige, Debra E.; Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, United States ; ADNET Systems, Inc., Bethesda, United States
Mahieu, Emmanuel ; Université de Liège - ULiège > Sphères ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO) > Groupe infra-rouge de physique atmosphérique et solaire (GIRPAS)
McConville, Glen; NOAA Global Monitoring Laboratory, Boulder, United States
Mellqvist, Johan ; Space Earth and Environment, Chalmers University of technology, Göteborg, Sweden
Morris, Gary ; NOAA Global Monitoring Laboratory, Boulder, United States
Murata, Isao; Graduate School of Environmental Studies, Tohoku University, Sendai, Japan
Nagahama, Tomoo ; Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
Nedoluha, Gerald E.; Naval Research Laboratory, Washington, United States
Ogino, Shin-Ya; Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Research Institute for Global Change, Yokosuka, Japan
Querel, Richard ; Earth Sciences New Zealand (ESNZ), Lauder, New Zealand
Stauffer, Ryan M. ; Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, United States
Stremme, Wolfgang ; Instituto de Ciencias de la Atmósfera y Cambio Climático, Universidad Nacional Autonoma de Mexico (UNAM), Mexico City, Mexico
Strong, Kimberly; Department of Physics, University of Toronto, Toronto, Canada
Sussmann, Ralf ; Karlsruhe Institute of Technology (KIT), IMKIFU, Garmisch-Partenkirchen, Germany
Thompson, Anne M. ; Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, United States ; University of Maryland – Baltimore County, Baltimore, United States
Virolainen, Yana ; St.Petersburg State University, St.Petersburg, Russian Federation
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