Radiation regime

 

During the year, the number of sunny days averages 322, or about 2,600 hours. The monthly sunshine time is the longest in July (332 hours), and the shortest in December (126 hours). The possible duration of solar radiation is 4,460 hours per year, and the actual mean duration during a long-term period is 2,584 hours per year, i.e. over 60%.

The relative duration of solar radiation 58 % year.  The number of sunless days 42 year.

The actual duration of the day in the city is a little shorter because of the horizon obscurrity by the mountains is 2-3^o in the north and 4-5^o in the south. The longest day (15 hours 18 minutes) is June22, the shortest day (8 hours 58 minutes) is December 22.

 Sunrise and sunset time in Bishkek (hours-minutes)

 With the sun height rising in May-September direct radiation accounts for 60-70% of the total radiation. From December to March the share of diffuse radiation is somewhat bigger than the share of direct radiation and is 52-55% of the total radiation. The largest quantity of the total radiation is observed at noon and its maximum energy emittance is 1.07 kW/m².

            With the increase of the quantity of aerosols in the atmosphere the diffuse radiation flow grows. Diffuse radiation grows strongly when there is snow on the ground and when there are high-level and medium-level clouds lit by the sun.

Sources:   Frunze the Encyclopedia, Frunze. 1984. - 228 p.  The climate of Frunze/ ed. by E.S.Skiba. – Leningrad, Gidrometeoizdat, 1990.- 136 p.