Solar and skylight measurements were made in southern Thailand from late February to early April of 1969. The aerosol optical density (basis 10) was rather large, ranging from 0.07 to 0.28 at λ0.5 µm and varied with about λ-2 in the range 0.5 < λ < 1.6 µm. The skylight scattering phase function was relatively flat and showed little spectral dependence. The log aerosol size distribution seems close to r-4. The origin of the turbid low level air from the South China Sea and Philippine Sea poses the question of the nature of the aerosol.
F. Volz and L. Sheehan, "Skylight and Aerosol in Thailand During the Dry Winter Season," Appl. Opt. 10, 363-366 (1971)