Space-based climatology of aerosol components

Abstract

At DLR-DFD a synergetic aerosol retrieval method SYNAER was developed which delivers aerosol optical thickness and type from simultaneous measurements of a radiometer (ATSR-2, AATSR, AVHRR) and a spectrometer (GOME, SCIAMACHY, GOME-2). The methodology and a first case study validation and application are described in 2 papers in JGR (T. Holzer-Popp, et al., JGR, 107, 2002). Exploiting measurements of GOME and ATSR-2 (ERS-2) of 3 days per month in the period July 1997 to August 1998 over Europe and Africa, a first climatological dataset was derived. The restriction to 3 days per month is due to the fact that GOME measures small pixels (80x40 km2) only every 4th/5th, 14th/15th, and 24th/25th for 24 hours each month. The climatological dataset thus suffers from a low number of available (cloud fraction below 35%) observations. However, it already shows the distribution of the major components of tropospheric aerosols: sulfate/ nitrate, soot, sea salt, and mineral dust. Equivalent sensor combinations onboard ENVISAT (AATSR, SCIAMACHY) and METOP (AVHRR, GOME-2) will deliver daily measurements with exploitable pixel size and thus provide the potential for a 20 year period of global data collecting for the compilation of an annual aerosol component climatology.