Ignatov, A, Minnis, P, Miller, WF, Wielicki, BA, Remer, L (2006). Consistency of global MODIS aerosol optical depths over ocean on Terra and Aqua CERES SSF data sets. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 111(D14), D14202.
 Aerosol retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Terra and Aqua platforms are available from the Clouds and the Earth's Radiant Energy System (CERES) Single Scanner Footprint (SSF) data sets. Over ocean, two aerosol products are reported side by side. The primary M product is generated by subsetting and remapping the multispectral (from 0.47 to 2.1 mu m) MOD04/MYD04 oceanic aerosol data onto CERES footprints. M*D04 processing uses cloud screening and aerosol algorithms developed by the MODIS science team. The secondary AVHRR-like A product is generated in only two MODIS bands. The A processing uses the CERES cloud-screening algorithm and NOAA/NESDIS glint identification and single-channel aerosol retrieval algorithms. The M and A products have been documented elsewhere and preliminarily compared using 2 weeks of global Terra CERES SSF edition 1A data, in which the M product was based on MOD04 collection 3. In this study, the comparisons between the M and A aerosol optical depths (AOD) in MODIS band 1 (0.64 mu m), tau(1M) and tau(1A), are reexamined using 9 days of global CERES SSF Terra edition 2A and Aqua edition 1B data from 13 to 21 October 2002 and extended to include cross-platform comparisons. The M and A products on the new CERES SSF release are generated using the same aerosol algorithms as before but with different preprocessing and sampling procedures, thus lending themselves to a simple sensitivity check to nonaerosol factors. Both tau(1M) and tau(1A) generally compare well across platforms. However, the M product shows larger differences, which increase with ambient cloud amount and toward the solar side of the orbit. The cross-platform, cross-product, and cross-release comparisons conducted in this study confirm an earlier observation that the major area for improvement in the current aerosol processing lies in a more formalized and standardized sampling (most importantly, cloud screening), whereas optimization of the aerosol algorithm is deemed to be an important yet less critical element.