We would like to thank R. Irish for help with the ACCA algorithm and J. Storey for help on the geolocation algorithm. L. Rocchio is thanked for being very helpful with Landsat data. We are very grateful to Y. Kaufman for the discussion of results, and O. Dubovik, I. Slutsker, and A. Smirnov for extensive AERONET support. The first author thanks M. Mischenko and L. Remer for the opportunity to discuss the results of this work at the seminars at GISS and GSFC. This work was supported by Landsat Program Office Grant 910-80-098, and partially by the IPO NOAA Grant NAO3AANEG0084.
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