Consistency of the MODIS-Derived Climatology of the Aerosol OConsistency of the MODIS-derived climatology of the aerosol over oceansver Oceans
Abstract
The MODIS (MODerate resolution Imaging Spectroradiometer) instrument on board both the Terra and Aqua satellites has been successfully retrieving aerosol characteristics over the ocean for the past 7 years. With its wide spectral range (0.47 to 2.13 μm) MODIS is able to derive spectral aerosol optical depth and information on the size of the aerosol particles. Far from land-based sources, we expect the long-term statistics of the aerosol optical thickness over the oceans to have negligible diurnal signal. Therefore, comparing large-scale regional and global mean aerosol optical thickness derived independently from Terra and Aqua MODIS data will provide a measure of the precision of the overall product. We analyze the three years of overlapping record of quality and pixel weighted Level 3 statistics. These data show that the instruments' measurement of the long-term global annual mean agree to within 1% or 0.0014 in optical thickness calculated from global monthly means. Two-thirds of the regions have long-term annual regional means that agree to within 2.5%. The highest regional difference is 5%, found over the southern circumpolar ocean. Other aerosol parameters such as particle size will show larger differences. Data sets such as Giovanni that are not quality- and pixel- weighted may also show larger differences.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2006
- Bibcode:
- 2006AGUFM.A53C0205K
- Keywords:
-
- 0305 Aerosols and particles (0345;
- 4801;
- 4906)