Seasonal and daily variations in the optical radiation extinction coefficient due to midges in the surface air in Western Siberia in summer-autumn 2018
N.N. Shchelkanov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: atmosphere, attenuation coefficient, midges, seasonal behavior, daily variation, Western Siberia
Abstract
The seasonal and daily variations in the radiation extinction coefficient due to midges (RECM) in Western Siberia are calculated for June, July, August, and September 2018. The average RECM values in the visible and infrared spectral regions were ~ 0.06 km-1 in June, ~ 0.05 km-1 in July, ~ 0.04 km-1 in August, and ~ 0.02 km-1 in September. There are two maxima in the daily variations in June, July, August, and September. The first maximum falls at 9 a.m. The second maximum is more pronounced and is observed at 17 p.m. The RECM is minimal in nighttime and at noon. In addition, a different daily behavior is characteristic for certain days of September, with a maximum in daytime and a minimum in nighttime.
|
