Daily Variation in the Radiation Extinction Coefficient due to Midges and Its Dependence on Meteorological Parameters of the Atmosphere in Background Summer Conditions of Western Siberia

Resumo

It is shown that the daily variation in the radiation extinction coefficient due to midges (RECM) has a statistically significant morning maximum at 09:00. This maximum is not connected with extremes of the air temperature or relative humidity. RECM maxima are observed at air temperatures of 12–17°C and relative air humidity of 60–80%. Correlations between RECM, air temperature, and relative humidity are statistically significant. The slope coefficient of the straight line in dependences of the midges-caused radiation extinction on the air temperature and relative humidity are –0.04 km^–1/5°C and +0.04 km^–1/20%, respectively. It is revealed that the RECM maxima are observed at winds of 2–4 m/s, directed from boggy forest areas, and minima, at winds of 1–4 m/s, directed from Ob River and dry, mixed, and boreal coniferous forests.