AMTD Atmospheric Measurement Techniques Discussions AMTD Atmos. Meas. Tech. Discuss. 1867-8610 Göttingen, Germany 10.5194/amtd-4-7597-2011 Aerosol optical depth retrieval in the Arctic region using MODIS based on prior knowledge Mei L. 1 8 Xue Y. 1 2 de Leeuw G. 3 4 5 Hou T. 6 8 Guang J. 1 Yang L. 7 Li Y. 1 8 Xu H. 1 8 He X. 1 8 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijin Faculty of Computing, London Metropolitan University, 166-220 Holloway Road, London N7 8DB, UK Department of Physics, University of Helsinki, Helsinki, Finland Finnish Meteorological Institute, Climate Change Unit, Helsinki, Finland Netherlands Organisation for Applied Scientific Research TNO, Utrecht, The Netherlands Center for Earth Observation and Digital Earth of the Chinese Academy of Sciences, Beijing 100094, China School of Geography, Beijing Normal University, Beijing 100875, China Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 19 12 2011 4 6 7597 7622 Copyright: © 2011 L. Mei et al. 2011 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/preprints/4/7597/2011/amtd-4-7597-2011.html The full text article is available as a PDF file from https://amt.copernicus.org/preprints/4/7597/2011/amtd-4-7597-2011.pdf

The Arctic is especially vulnerable to the long-term transport of aerosols and other pollutants because aerosols can affect the albedo of the surface by deposition on snow and ice. However, aerosol observations for this area are sparse and hence there is considerable uncertainty in the knowledge on the properties of the Arctic aerosol. Arctic aerosol observations are needed to fill this gap because these are among the basic and most important parameters for researching the Arctic environment. Atmospheric remote sensing using satellites offers us an opportunity to describe the aerosol distribution in terms of both local, regional and global coverage. However, AOD retrieval over a bright surface remains a difficult task because it is hard to separate and explicitly describe the contribution of the observed signal reflected by the variable surface and back scattering by the semi-transparent aerosols, especially with a large solar or sensor zenith angle. In this paper, an approach using a synergetic approach with Moderate Resolution Imaging Spectroradiometer (MODIS) data based on prior knowledge is presented. The detailed analysis of the model demonstrates that it is suitable for Arctic region AOD retrieval. Six AERONET stations at high latitude (Andenes, Barrow, Ittoqqortoormiit, OPAL, Thule, and Tiksi) were used for validation, and the correlation coefficient between retrieved AODs and AERONET AODs was 0.75 and the retrieval absolute error is approximately 0.1, while the relative error is 20% (at some stations with clear skies as low as 10% was found). Furthermore, the Russian wildfires that occurred in late July of 2010 and their effect on the Arctic environment is presented; Satellite retrieved AODs in the Arctic increased to 1.0 during 1 August and 15 August 2010, even 2.0, during the burning phase, and subsequently returned to normal values (lower than 0.1), which was fully in line with the AERONET observations. This indicates that the fire plumes were transported to the Arctic region.

 References Ackerman,&nbsp;T.&nbsp;P., Stemback,&nbsp;J.&nbsp;N., and Valero,&nbsp;F.&nbsp;P.&nbsp;J.: The importance of Arctic haze for the energy budget of the Arctic, in: Arctic Air Pollution, Cambridge University Press, Cambridge, 151–158, 1986. Ångström,&nbsp;A.: On the atmospheric transmission of sun radiation and on dust in the air, Geograf. Ann., 11, 156–169, 1929. Damoah,&nbsp;R., Spichtinger,&nbsp;N., Forster,&nbsp;C., James,&nbsp;P., Mattis,&nbsp;I., Wandinger,&nbsp;U., Beirle,&nbsp;S., Wagner,&nbsp;T., and Stohl,&nbsp;A.: Around the world in 17 days – hemispheric-scale transport of forest fire smoke from Russia in May 2003, Atmos. Chem. Phys., 4, 1311-1321, <a href="http://dx.doi.org/10.5194/acp-4-1311-2004">https://doi.org/10.5194/acp-4-1311-2004</a>, 2004. Deuze,&nbsp;J.&nbsp;L., Breon,&nbsp;F.&nbsp;M., Devaux,&nbsp;C., Goloub,&nbsp;P., Herman,&nbsp;M., Lafrance,&nbsp;B., Maignan,&nbsp;F., Marchand,&nbsp;A., Nadal,&nbsp;F., Perry,&nbsp;G., and Tanre,&nbsp;D.: Remote sensing of aerosols over land surfaces from POLDER-ADEOS-1 polarized measurements, J. Geophys. Res., 106, 4913–4926, 2001. De Abreu,&nbsp;R.&nbsp;A., Key,&nbsp;J., Maslanik,&nbsp;J.&nbsp;A., Serreze,&nbsp;M.&nbsp;C., and LeDrew,&nbsp;E.&nbsp;F.: Comparison of in situ and AVHRR-Derived Broadband Albedo over Arctic Sea Ice, Arctic, 47, 288–297, 1994. Diner,&nbsp;D.&nbsp;J., Martonchik,&nbsp;J.&nbsp;V., Kahn,&nbsp;R.&nbsp;A., Pinty,&nbsp;B., Gobron,&nbsp;N., Nelson,&nbsp;D.&nbsp;L., and Holben,&nbsp;B.&nbsp;N.: Using angular and spectral shape similarity constraints to improve MISR aerosol and surface retrievals over land, Remote Sens. Environ., 94, 155–171, 2005. Flowerdew,&nbsp;R.&nbsp;J. and Haigh,&nbsp;J.&nbsp;D.: An approximation to improve accuracy in the derivation of surface reflectances from multi-look satellite radiometers, Geophys. Res. Lett., 22, 1693–1696, 1995. Gatebe,&nbsp;C.&nbsp;K., King,&nbsp;M.&nbsp;D., Tsay,&nbsp;S.&nbsp;C., Ji,&nbsp;Q., Thomas,&nbsp;A.&nbsp;G., and Li,&nbsp;J.&nbsp;Y.: Sensitivity of off-nadir zenith angles to correlation between visible and near-infrared reflectance for use in remote sensing of aerosol over land, IEEE T. Geosci. Remote Sens., 39, 805–819, 2001. Grey,&nbsp;W.&nbsp;M.&nbsp;F., North,&nbsp;P.&nbsp;R.&nbsp;J., Los,&nbsp;S.&nbsp;O., and Mitchell,&nbsp;R.&nbsp;M.: Aerosol optical depth and land surface reflectance from multi-angle AATSR measurements: global validation and inter-sensor comparisons, IEEE T. Geosci. Remote Sens., 44, 2184–2197, 2006. Govaerts,&nbsp;Y.&nbsp;M., Wagner,&nbsp;S., Lattanzio,&nbsp;A., and Watts,&nbsp;P.: Joint retrieval of surface reflectance and aerosol optical depth from MSG/SEVIRI observations with an optimal estimation approach: 1. Theory, J. Geophys. Res., 115, D02203, <a href="http://dx.doi.org/10.1029/2009JD011779">https://doi.org/10.1029/2009JD011779</a>, 2010. Herber,&nbsp;A., Thomason,&nbsp;L.&nbsp;W., Dethloff,&nbsp;K., Viterbo,&nbsp;P., Radionov,&nbsp;V.&nbsp;F., and Leiterer,&nbsp;U.: Volcanic perturbation of the atmosphere in both polar regions: 1991–1994, J. Geophys. Res., 101, 3921–3928, <a href="http://dx.doi.org/10.1029/95JD02462">https://doi.org/10.1029/95JD02462</a>, 1996. Holzer-Popp,&nbsp;T., Schroedter,&nbsp;M., and Gesell,&nbsp;G.: Retrieving aerosol optical depth and type in the boundary layer over land and ocean from simultaneous GOME spectrometer and ATSR-2 radiometer measurements, 1, Method description, J. Geophys. Res., 107, AAC16-1–AAC16-17, <a href="http://dx.doi.org/10.1029/2001JD002013">https://doi.org/10.1029/2001JD002013</a>, 2002. Hsu,&nbsp;N.&nbsp;C., Tsay,&nbsp;S.&nbsp;C., King,&nbsp;M.&nbsp;D., and Herman,&nbsp;J.&nbsp;R.: Aerosol properties over bright reflecting source regions, IEEE T. Geosci. Remote Sens., 42, 557–569, 2004. Ichoku,&nbsp;C., Chu,&nbsp;D.&nbsp;A., Mattoo,&nbsp;S., Kaufman,&nbsp;Y.&nbsp;J., Remer,&nbsp;L.&nbsp;A., Tanre,&nbsp;D., Slutsker,&nbsp;I., and Holben,&nbsp;B.&nbsp;N.: A&nbsp;spatio-temporal approach for global validation and analysis of MODIS aerosol products, Geophys. Res. Lett., 29, MOD1-1-MOD1-4, <a href="http://dx.doi.org/10.1029/2001GL013206">https://doi.org/10.1029/2001GL013206</a>, 2002. Istomina,&nbsp;L.&nbsp;G., von&nbsp;Hoyningen-Huene,&nbsp;W., Kokhanovsky,&nbsp;A.&nbsp;A., Schultz,&nbsp;E., and Burrows,&nbsp;J.&nbsp;P.: Remote sensing of aerosols over snow using infrared AATSR observations, Atmos. Meas. Tech., 4, 1133–1145, <a href="http://dx.doi.org/10.5194/amt-4-1133-2011">https://doi.org/10.5194/amt-4-1133-2011</a>, 2011. Kaufman,&nbsp;Y.&nbsp;J., Tanre,&nbsp;D., Remer,&nbsp;L.&nbsp;A., Vermote,&nbsp;E.&nbsp;F., Chu,&nbsp;A., and Holben,&nbsp;B.&nbsp;N.: Operational remote sensing of tropospheric aerosol over land from EOS moderate resolution imaging spectroradiometer, J. Geophys. Res., 102, 17051–17067, <a href="http://dx.doi.org/10.1029/96JD03988">https://doi.org/10.1029/96JD03988</a>, 1997. Key,&nbsp;J.&nbsp;R., Santek,&nbsp;D., Velden,&nbsp;C.&nbsp;S., Bormann,&nbsp;N., Thépaut,&nbsp;J.-N., Riishojgaard,&nbsp;L.&nbsp;P., Zhu,&nbsp;Y.&nbsp;Q., and Menzel,&nbsp;W.&nbsp;P.: Cloud-drift and water vapor winds in the polar regions from MODIS, IEEE T. Geosci. Remote Sens., 41, 482–492, 2003. Kim,&nbsp;Y., Hatsushika,&nbsp;H., Muskett,&nbsp;R.&nbsp;R., and Yamazaki,&nbsp;K.: Possible effect of boreal wildfire soot on Arctic sea ice and Alaska glaciers, Atmos. Environ., 39, 3513–3520, 2005. Kondratyev.&nbsp;K.&nbsp;Y.: Radiation in the Atmosphere, Academic Press, New York, London, 1969. Kuznetzov,&nbsp;E.&nbsp;S.: On the problem of approximate transfer equations in a&nbsp;scattering and absorbing medium, Rep. Acad. Sci. USSR, 37, Nos 7 and 8, 1942. Levy,&nbsp;R.&nbsp;C., Remer,&nbsp;L., Mattoo,&nbsp;S., Vermote,&nbsp;E.&nbsp;F., and Kaufman,&nbsp;Y.&nbsp;J.: Second-generation algorithm for retrieving aerosol properties over land from MODIS spectral reflectance, J. Geophys. Res., 112, D13211, <a href="http://dx.doi.org/10.1029/2006JD007811">https://doi.org/10.1029/2006JD007811</a>, 2007. Martonchik,&nbsp;J.&nbsp;V., Kahn,&nbsp;R.&nbsp;A., and Diner,&nbsp;D.&nbsp;J.: Retrieval of aerosol properties over land using MISR observations, in: Satellite Aerosol Remote Sensing Over Land, published in association with Praxis Publishing, Chichester, 267–268, 2009. Mei, L., Xue, Y., de Leeuw, G., Guang, J., Wang, Y., Li, Y., Xu, H., Yang, L., Hou, T., He, X., Wu, C., Dong, J., and Chen, Z.: Integration of remote sensing data and surface observations to estimate the impact of the russian wildfires over Europe and Asia during August 2010, Biogeosciences Discuss., 8, 7741–7790, <a href="http://dx.doi.org/10.5194/bgd-8-7741-2011">https://doi.org/10.5194/bgd-8-7741-2011</a>, 2011. Remer,&nbsp;L.&nbsp;A., Wald,&nbsp;A.&nbsp;E., and Kaufman,&nbsp;Y.&nbsp;J.: Angular and seasonal variation of spectral surface reflectance rations: implications for the remote sensing of aerosol over land, IEEE T. Geosci. Remote Sens, 39, 275–283, 2001. Remer,&nbsp;L.&nbsp;A., Kaufman,&nbsp;Y.&nbsp;J., Tanre,&nbsp;D., Mattoo,&nbsp;S., Chu,&nbsp;D.&nbsp;A., Martins,&nbsp;J.&nbsp;V., Li,&nbsp;R.&nbsp;R., Ichoku,&nbsp;C., Levy,&nbsp;R.&nbsp;C., Kleidman,&nbsp;R.&nbsp;G., Eck,&nbsp;T.&nbsp;F., Vermote,&nbsp;E., and Holben,&nbsp;B.&nbsp;N.: The MODIS aerosol algorithm, products, and validation, J. Atmos. Sci., 62, 947–973, 2005. Remer,&nbsp;L.&nbsp;A., Tanré&nbsp;D., and Kaufman&nbsp;Y.&nbsp;J.: Algorithm for Remote Sensing of Tropospheric Aerosol from MODIS: Collection 5, ATBD_MOD_02.pdf, 1&nbsp;November&nbsp;2006, <a href="http://modis.gsfc.nasa.gov/data/atbd/atmos_atbd.php">http://modis.gsfc.nasa.gov/data/atbd/atmos_atbd.php</a>, last access:&nbsp;10&nbsp;October&nbsp;2011, 2006. Shaw,&nbsp;G.&nbsp;E.: The Arctic haze phenomenon, B. Am. Meteorol. Soc., 2403–2413, 1995. Santer,&nbsp;R., Carrere,&nbsp;V., Dubuisson,&nbsp;P., and Roger,&nbsp;J.&nbsp;C.: Atmospheric corrections over land for MERIS, Int. J. Remote Sens., 20, 1819–1840, 1999. Tang,&nbsp;J., Xue,&nbsp;Y., Yu,&nbsp;T., and Guan,&nbsp;Y.: Aerosol optical thickness determination by exploiting the synergy of TERRA and AQUA MODIS, Remote Sens. Environ., 94, 327–334, 2005. Veefkind,&nbsp;J.&nbsp;P., de Leeuw,&nbsp;G., and Durkee,&nbsp;P.&nbsp;A.: Retrieval of aerosol optical depth over land using two-angle view satellite radiometry during TARFOX, Geophys. Res. Lett., 25, 3135–3138, 1998. Wang&nbsp;Y., Xue,&nbsp;Y., Li,&nbsp;Y.&nbsp;J., Guang,&nbsp;J., Mei,&nbsp;L.&nbsp;L., Xu,&nbsp;H., and Ai,&nbsp;J.&nbsp;W.: Prior knowledge supported aerosol optical depth retrieval over land surface at 500 m spatial resolution with MODIS data, Int. J. Remote Sens., 33, 674–691, 2012. Warren,&nbsp;S.&nbsp;G.: Optical properties of snow, Rev. Geophys. Space Phys., 20, 67–89, <a href="http://dx.doi.org/10.1029/RG020i001p00067">https://doi.org/10.1029/RG020i001p00067</a>, 1982. Wagner,&nbsp;S.&nbsp;C., Govaerts,&nbsp;Y.&nbsp;M., and Lattanzio,&nbsp;A.: Joint retrieval of surface reflectance and aerosol optical depth from MSG/SEVIRI observations with an optimal estimation approach: 2. Implementation and evaluation, J. Geophys. Res., 115, D02204, <a href="http://dx.doi.org/10.1029/2009JD011780">https://doi.org/10.1029/2009JD011780</a>, 2010. Xue,&nbsp;Y. and Cracknell,&nbsp;A.&nbsp;P.: Operational bi-angle approach to retrieve the Earth surface albedo from AVHRR data in the visible band, Int. J. Remote Sens., 16, 417–429, 1995.