References

AMT

Atmospheric Measurement Techniques

AMT

Atmos. Meas. Tech.

1867-8548

Copernicus Publications

Göttingen, Germany

10.5194/amt-5-631-2012

1D-Var retrieval of daytime total columnar water vapour from MERIS measurements

Lindstrot

¹ Preusker

¹ Diedrich

¹ Doppler

¹ Bennartz

² Fischer

Institut für Weltraumwissenschaften, Freie Universität Berlin, Carl-Heinrich-Becker-Weg 6–10, 12165 Berlin, Germany

Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison, 1225 W. Dayton Street, Madison, WI, USA

27 03 2012

5 3 631 646

2012

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://amt.copernicus.org/articles/5/631/2012/amt-5-631-2012.html

The full text article is available as a PDF file from https://amt.copernicus.org/articles/5/631/2012/amt-5-631-2012.pdf

A new scheme for the retrieval of total columnar water vapour from measurements of MERIS (Medium Resolution Imaging Spectrometer) on ENVISAT (ENVIronmental SATellite) is presented. The algorithm is based on a fast forward model of the water vapour transmittance around 900nm, including a correction for atmospheric scattering and the influence of the temperature- and pressure-profile on the water vapour absorption lines. It provides the water vapour column amount for cloud-free scenes above land and ocean at a spatial resolution of 0.25 km × 0.3 km and 1 km × 1.2 km, depending on whether applied to the "full resolution" or the operational "reduced resolution" mode of MERIS. Uncertainties are provided on a pixel-by-pixel basis, taking into account all relevant sources of error. An extensive validation against various sources of ground-based reference data reveals a high accuracy of MERIS water vapour above land (root mean square deviations between 1.4 mm and 3.7 mm), apart from a wet bias of MERIS between 5 and 10% that is found in all comparison studies. This wet bias might be caused by spectroscopic uncertainties, such as the description of the water vapour continuum. Above ocean the accuracy is reduced, due to the uncertainty introduced by the unknown atmospheric scattering. Consequently, an increased root mean square deviation of ≥5 mm was found by comparing MERIS total columnar water vapour above ocean against SSM/I and ENVISAT MWR data. An increased wet bias of 2–3 mm is found over ocean, potentially due to a not properly working atmospheric correction scheme.

References 1

Albert, P., Bennartz, R., Preusker, R., Leinweber, R., and Fischer, J.: Remote Sensing of Atmospheric Water Vapor Using the Moderate Resolution Imaging Spectroradiometer (MODIS), J. Atmos. Ocean. Tech., 22, 309–314, 2005.

Bender, M. and Raabe, A.: Preconditions to ground based GPS water vapour tomography, Ann. Geophys., 25, 1727–1734, <a href="http://dx.doi.org/10.5194/angeo-25-1727-2007">https://doi.org/10.5194/angeo-25-1727-2007</a>, 2007.

Bennartz, R. and Fischer, J.: A modified <i>k</i>-distribution approach applied to narrow band water vapour and oxygen absorption estimates in the near infrared, J. Quant. Spectrosc. Ra., 66, 539–553, 2000.

Bennartz, R. and Fischer, J.: Retrieval of columnar water vapour over land from back-scattered solar radiation using the Medium Resolution Imaging Spectrometer (MERIS), Remote Sens. Environ., 78, 271–280, 2001.

Clough, S. A., Shephard, M. W., Mlawer, E. J., Delamere, J. S., Iacono, M. J., Cady-Pereira, K., Boukabara, S., and Brown, P. D.: Atmospheric radiative transfer modeling: a summary of the AER codes, Short Communication, J. Quant. Spectrosc. Ra., 91, 233–244, 2005.

Cox, C. and Munk, W.: Measurement of the Roughness of the Sea Surface from Photographs of the Sun`s Glitter, J. Opt. Soc. Am., 44, 838–850, 1954.

Deblonde, G.: NWP SAF User`s Guide: Standalone 1D-var scheme for the SSM/I, SSMIS and AMSU, NWPSAF-MO-UD-001 Version 1.0, 2001.

Delwart, S., Preusker, R., Bourg, L., Santer, R., Ramon, D., and Fischer, J.: MERIS inflight spectral calibration, Int. J. Remote Sens., 28, 479–496, 2007.

Fell, F. and Fischer, J.: Numerical simulation of the light field in the atmosphere-ocean system using the matrix-operator method, J. Quant. Spectrosc. Ra., 3, 351–388, 2001.

Fischer, J.: High-resolution spectroscopy for remote sensing of physical cloud properties and water vapour, in: Current problems in atmospheric radiation, edited by: Lenoble, J. and Geleyn, J.-F., Deepak Publishing, Hampton, Virginia, USA, 151–156, 1988.

Fischer, J. and Grassl, H.: Radiative transfer in an atmosphere-ocean system: an azimuthally dependent matrix-operator approach, Appl. Optics, 23, 1035–1039, 1984.

Fischer, J., Leinweber, R., and Preusker, R.: ATBD 2.4 Retrieval of Total Water Vapour Content from MERIS Measurements, Algorithm Theoretical Basis Document, European Space Agency, <a href="http://envisat.esa.int/instruments/meris/atbd/atbd_2.4.pdf">http://envisat.esa.int/instruments/meris/atbd/atbd_2.4.pdf</a> (last access: 20 March 2012), 2010.

Gao, B.-C. and Kaufman, Y. J.: Water vapor retrievals using Moderate Resolution Imaging Spectroradiometer (MODIS) near-infrared channels, J. Geophys. Res., 108, 4389, <a href="http://dx.doi.org/10.1029/2002JD003023">https://doi.org/10.1029/2002JD003023</a>, 2003.

Gendt, G., Dick, G., and Stihne, W.: GFZ Analysis Center of IGS – Annual Report 1998, IGS 1998 Technical Reports, edited by: Gowey, K., Neilan, R., and Moore, A., Tech. rep., Jet Propulsion Laboratory, Pasadena, 1999.

Gendt, G., Dick, G., Reigber, C., Tomassini, M. Y. L., and Ramatschi, M.: Near Real Time GPS Water Vapor Monitoring for Numerical Weather Prediction in Germany, J. Meteorol. Soc. Jpn., 82, 361–370, 2004.

Guanter, L., Gómez-Chova, L., and Moreno, J.: Coupled retrieval of aerosol optical thickness, columnar water vapor and surface reflectance maps from ENVISAT/MERIS data over land, Remote Sens. Environ., 112, 2898–2913, <a href="http://dx.doi.org/10.1016/j.rse.2008.02.001">https://doi.org/10.1016/j.rse.2008.02.001</a>, 2008.

Heise, S., Wickert, J., Beyerle, G., Schmidt, T., and Reigber, C.: Global monitoring of tropospheric water vapor with GPS radio occultation aboard CHAMP, Adv. Space Res., 37, 2222–2227, <a href="http://dx.doi.org/10.1016/j.asr.2005.06.066">https://doi.org/10.1016/j.asr.2005.06.066</a>, 2006.

Hollstein, A. and Fischer, J.: Radiative transfer solutions for coupled atmosphere ocean systems using the matrix operator technique, J. Quant. Spectrosc. Ra., 113, 536–548, <a href="http://dx.doi.org/10.1016/j.jqsrt.2012.01.010">https://doi.org/10.1016/j.jqsrt.2012.01.010</a>, 2012.

Koepke, P.: Effective reflectance of oceanic whitecaps, Appl. Optics, 23, 1816–1824, 1984.

Lindstrot, R., Preusker, R., and Fischer, J.: The empirical correction of stray light in the MERIS oxygen A band channel, J. Atmos. Ocean. Tech., 27, 1185–1194, 2010.

McClatchey, R., Fenn, R., Selby, J., Volz, F., and Garing, J.: Optical Properties of the Atmosphere, 3rd Edn., Air Force Cambridge Research Laboratories, 1972.

Michalsky, J. J., Liljegren, J. C., and Harrison, L. C.: A comparison of Sun photometer derivations of total column water vapor and ozone to standard measures of same at the Southern Great Plains Atmospheric Radiation Measurement site, J. Geophys. Res., 100, 25995–26003, <a href="http://dx.doi.org/10.1029/95JD02706">https://doi.org/10.1029/95JD02706</a>, 1995.

Miloshevich, L. M., Paukkunen, A., Vömel, H., and Oltmans, S. J.: Development and Validation of a Time-Lag Correction for Vaisala Radiosonde Humidity Measurements, J. Atmos. Ocean. Tech., 21, 1305–1327, 2004.

Muller, J.-P., Preusker, R., Fischer, J., Zuhlke, M., Brockmann, C., and Regner, P.: ALBEDOMAP: MERIS land surface albedo retrieval using data fusion with MODIS BRDF and its validation using contemporaneous EO and in situ data products, in: IGARSS International Geoscience and Remote Sensing Symposium 2007, 2404–2407, <a href="http://dx.doi.org/10.1109/IGARSS.2007.4423326">https://doi.org/10.1109/IGARSS.2007.4423326</a>, 2007.

Noël, S., Buchwitz, M., Bovensmann, H., and Burrows, J. P.: Retrieval of total water vapour column amounts from GOME/ERS-2 data, Adv. Space Res., 29, 1697–1702, 2002.

Noël, S., Buchwitz, M., and Burrows, J. P.: First retrieval of global water vapour column amounts from SCIAMACHY measurements, Atmos. Chem. Phys., 4, 111–125, <a href="http://dx.doi.org/10.5194/acp-4-111-2004">https://doi.org/10.5194/acp-4-111-2004</a>, 2004.

Obligis, E., Eymard, L., Tran, N., Labroue, S., and Femenias, P.: First three years of the microwave radiometer aboard ENVISAT: In-fight calibration, processing, and validation of the geophysical products, J. Atmos. Ocean. Tech., 23, 802–814, 2006.

Phalippou, L.: Variational retrieval of humidity profile, wind speed and cloud liquid-water path with the SSM/I: Potential for numerical weather prediction, Q. J. Roy. Meteorol. Soc., 122, 327–355, 1996.

Pougatchev, N., August, T., Calbet, X., Hultberg, T., Oduleye, O., Schlüssel, P., Stiller, B., Germain, K. St., and Bingham, G.: IASI temperature and water vapor retrievals – error assessment and validation, Atmos. Chem. Phys., 9, 6453–6458, <a href="http://dx.doi.org/10.5194/acp-9-6453-2009">https://doi.org/10.5194/acp-9-6453-2009</a>, 2009.

Ptashnik, I. V., Shine, K. P., and Vigasin, A. A.: Water vapour self-continuum and water dimers: 1. Analysis of recent work, J. Quant. Spectrosc. Ra., 112, 1286–1303, 2011.

Rast, M., Bezy, J. L., and Bruzzi, S.: The ESA Medium Resolution Imaging Spectrometer MERIS – A review of the instrument and its mission, Int. J. Remote Sens., 20, 1681–1702, 1999.

Reagan, J. A., Thome, K., Herman, B., and Gali, R.: Water vapor measurements in the 0.94 m absorption band: Calibration, measurements, and data applications, in: Proceedings: International Geoscience and Remote Sensing Symposium, '87 Symposium, Ann Arbor, Michigan, IEEE, 63–67, 1987.

Rodgers, C.: Inverse Methods for Atmospheric Sounding: Theory and Practice, World Scientific, London, 2000.

Rothman, L., Gordon, I., Barbe, A., Benner, D., Bernath, P., Birk, M., Boudon, V., Brown, L., Campargue, A., Champion, J.-P., Chance, K., Coudert, L., Dana, V., Devi, V., Fally, S., Flaud, J.-M., Gamache, R., Goldman, A., Jacquemart, D., Kleiner, I., Lacome, N., Lafferty, W., Mandin, J.-Y., Massie, S., Mikhailenko, S., Miller, C., Moazzen-Ahmadi, N., Naumenko, O., Nikitin, A., Orphal, J., Perevalov, V., Perrin, A., Predoi-Cross, A., Rinsland, C., Rotger, M., Simeckova, M., Smith, M., Sung, K., Tashkun, S., Tennyson, J., Toth, R., Vandaele, A., and Auwera, J. V.: The {HITRAN} 2008 molecular spectroscopic database, J. Quant. Spectrosc. Ra., 110, 533–572, <a href="http://dx.doi.org/10.1016/j.jqsrt.2009.02.013">https://doi.org/10.1016/j.jqsrt.2009.02.013</a>, 2009.

Schlüssel, P. and Emery, W. J.: Atmospheric water vapour over oceans from SSM/I measurements, Int. J. Remote Sens., 11, 753–766, <a href="http://dx.doi.org/10.1080/01431169008955055">https://doi.org/10.1080/01431169008955055</a>, 1990.

Schmid, B., Thome, K., Demoulin, P., Peter, R., Matzler, C., and Sekler, J.: Comparison of modeled and empirical approaches for retrieving columnar water vapor from solar transmittance measurements in the 0.94 micron region, J. Geophys. Res., 101, 9345–9358, 1996.

Susskind, J., Barnet, C. D., and Blaisdell, J. M.: Retrieval of atmospheric and surface parameters from AIRS/AMSU/HSB data in the presence of clouds, IEEE T. Geosci. Remote, 41, 390–409, 2003.

Thuillier, G., Hersé, M., Labs, D., Foujols, T., Peetermans, W., Gillotay, D., Simon, P. C., and Mandel, H.: The solar spectral irradiance from 200 to 2400 nm as measured by the SOLSPEC spectrometer from the ATLAS and EURECA missions, Sol. Phys., 224, 1–22, 2003.

Turner, D. D., Lesht, B. M., Clough, S., Liljegren, J., Revercomb, H. E., and Tobin, D. C.: Dry bias and variability in VAISALA RS80-H radiosondes: The ARM experience, J. Atmos. Ocean. Tech., 20, 117–132, 2003.

Turner, D. D., Clough, S. A., Liljegren, J. C., Clothiaux, E. E., Cady-Pereira, K., and Gaustad, K. L.: Retrieving liquid water path and precipitable water vapor from Atmospheric Radiation Measurement (ARM) microwave radiometers, IEEE T. Geosci. Remote, 45, 3680–3690, <a href="http://dx.doi.org/10.1109/TGRS.2007.903703">https://doi.org/10.1109/TGRS.2007.903703</a>, 2007.

US GeologicalSurvey: Global 30 Arc-Second Elevation Data Set, <a href="http://www1.gsi.go.jp/geowww/globalmap-gsi/gtopo30/README.html">http://www1.gsi.go.jp/geowww/globalmap-gsi/gtopo30/README.html</a> (last access: 20 March 2012), 1996.