Climatology of dust aerosol size distribution and optical properties derived from remotely sensed data in the solar spectrum Academic Article uri icon

abstract

  • Simultaneous spectral remote observations of dust properties from space and from the ground create a powerful tool for the determination of ambient dust properties integrated on the entire atmospheric column. The two measurement methods have a complementary sensitivity to variety of dust properties. The methodology is demonstrated using spectral measurements (0.47-2.21 mm) from Landsat TM over the bright Senegalian coast and dark ocean, and Aerosol Robotic Network (AERONET) radiances measured in several locations. We derive (1) the dust size distribution, showing a dominant coarse mode at 1-5 mm and a secondary mode around 0.5 mm effective radius; (2) dust absorption, which is found to be substantially smaller than reported from previous measurements; (3) the real part of the refractive index which varies within the range 1.53- 1.46; and we show that (4) the effect of the dust nonspherical shape on its optical properties is not significant for scattering angles ,1208.

publication date

  • January 1, 2001