Methane retrieved from TROPOMI: improvement of the data product and validation of the first 2 years of measurements
-
Published:2021-01-28
Issue:1
Volume:14
Page:665-684
-
ISSN:1867-8548
-
Container-title:Atmospheric Measurement Techniques
-
language:en
-
Short-container-title:Atmos. Meas. Tech.
Author:
Lorente AlbaORCID, Borsdorff TobiasORCID, Butz AndreORCID, Hasekamp Otto, aan de Brugh Joost, Schneider Andreas, Wu LianghaiORCID, Hase Frank, Kivi RigelORCID, Wunch DebraORCID, Pollard David F.ORCID, Shiomi Kei, Deutscher Nicholas M.ORCID, Velazco Voltaire A.ORCID, Roehl Coleen M., Wennberg Paul O.ORCID, Warneke Thorsten, Landgraf Jochen
Abstract
Abstract. The TROPOspheric Monitoring Instrument (TROPOMI) on board the Sentinel 5 Precursor (S5-P) satellite provides methane (CH4) measurements with high accuracy and exceptional temporal and spatial resolution and sampling. TROPOMI CH4 measurements are highly valuable to constrain emissions inventories and for trend analysis, with strict requirements on the data quality. This study describes the improvements that we have implemented to retrieve CH4 from TROPOMI using the RemoTeC full-physics algorithm. The updated retrieval algorithm features a constant regularization scheme of the inversion that stabilizes the retrieval and yields less scatter in the data and includes a higher resolution surface altitude database. We have tested the impact of three state-of-the-art molecular spectroscopic databases (HITRAN 2008, HITRAN 2016 and Scientific Exploitation of Operational Missions – Improved Atmospheric Spectroscopy Databases SEOM-IAS) and found that SEOM-IAS provides the best fitting results. The most relevant update in the TROPOMI XCH4 data product is the implementation of an a posteriori correction fully independent of any reference data that is more accurate and corrects for the underestimation at low surface albedo scenes and the overestimation at high surface albedo scenes. After applying the correction, the albedo dependence is removed to a large extent in the TROPOMI versus satellite (Greenhouse gases Observing SATellite – GOSAT) and TROPOMI versus ground-based observations (Total Carbon Column Observing Network – TCCON) comparison, which is an independent verification of the correction scheme. We validate 2 years of TROPOMI CH4 data that show the good agreement of the updated TROPOMI CH4 with TCCON (−3.4 ± 5.6 ppb) and GOSAT (−10.3 ± 16.8 ppb) (mean bias and standard deviation). Low- and high-albedo scenes as well as snow-covered scenes are the most challenging for the CH4 retrieval algorithm, and although the a posteriori correction accounts for most of the bias, there is a need to further investigate the underlying cause.
Funder
Australian Research Council
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference52 articles.
1. Aben, I., Hasekamp, O., and Hartmann, W.: Uncertainties in the space-based
measurements of CO2 columns due to scattering in the Earth's atmosphere,
J. Quant. Spectrosc. Ra., 104, 450–459,
https://doi.org/10.1016/j.jqsrt.2006.09.013, 2007. a, b 2. Barré, J., Aben, I., Agustí-Panareda, A., Balsamo, G., Bousserez, N., Dueben, P., Engelen, R., Inness, A., Lorente, A., McNorton, J., Peuch, V.-H., Radnoti, G., and Ribas, R.: Systematic detection of local CH4 emissions anomalies combining satellite measurements and high-resolution forecasts, Atmos. Chem. Phys. Discuss. [preprint], https://doi.org/10.5194/acp-2020-550, in review, 2020. a 3. Birk, M., Wagner, G., Loos, J., Wilzewski, J., Mondelain, D., Campargue, A.,
Hase, F., Orphal, J., Perrin, A., Tran, H., Daumont, L., Rotger-Languereau,
M., Bigazzi, A., and Zehner, C.: Methane and water spectroscopic database for
TROPOMI Sentinel 5 Precursor in the 2.3 µm region, vol. 19, p.
4652, EGU General Assembly, 2017. a 4. Borsdorff, T., aan de Brugh, J., Schneider, A., Lorente, A., Birk, M., Wagner, G., Kivi, R., Hase, F., Feist, D. G., Sussmann, R., Rettinger, M., Wunch, D., Warneke, T., and Landgraf, J.: Improving the TROPOMI CO data product: update of the spectroscopic database and destriping of single orbits, Atmos. Meas. Tech., 12, 5443–5455, https://doi.org/10.5194/amt-12-5443-2019, 2019. a 5. Buchwitz, M., Reuter, M., Schneising, O., Hewson, W., Detmers, R. G., Boesch,
H., Hasekamp, O., Aben, I., Bovensmann, H., Burrows, J., Butz, A.,
Chevallier, F., Dils, B., Frankenberg, C., Heymann, J., Lichtenberg, G.,
De Mazière, M., Notholt, J., Parker, R., Warneke, T., Zehner, C., Griffith,
D. W. T., Deutscher, N., Kuze, A., Suto, H., and Wunch, D.: Global satellite
observations of column-averaged carbon dioxide and methane: The GHG-CCI
XCO2 and XCH4 CRDP3 data set, Remote Sens. Environ., 203, 276–295, https://doi.org/10.1016/j.rse.2016.12.027,
2017. a
Cited by
95 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|