For the 1934–50 period, monthly data come from Chernigovskiy (1961a, b). These works contain monthly totals of all three kinds of solar radiation for each year, as well as their long-term means. All available original data (solar totals) are expressed in cal/cm2/min in the pyrheliometric Ångström scale. For the purposes of comparability in presenting solar conditions they were recalculated to MJ/m2 units in the WRR (World Radiometric Reference) from 1981. Recalculation coefficients for the pyrheliometric scale were taken from the Roshydromet guidance document (Guidance document [GD 52.04.562–96], 1997).
The few gaps in the gathered monthly totals of particular solar radiation components were filled using the following formula:
I’ + D = Q,
where:
I’ – monthly sum of direct solar radiation falling on the horizontal surface,
D – monthly sum of diffuse solar radiation,
Q – monthly sum of global solar radiation.
Contemporary (2001-2019) solar radiation data were taken from: A.I. Voeikov Main Geophysical Observatory, Reference Database Data Bank (RSBD) "ACTINOMETRY". Certificate of State Registration RF BD No. 2011620235.
References:
Chernigovskiy, N.T., 1961a: Compedium of actinometry of the Soviet Arctic, 1931-1956. Trudy AANI, 233(1), p. 271 (in Russian).
Chernigovskiy, N.T., 1961b: Compedium of actinometry of the Soviet Arctic, 1931-1956. Trudy AANI, 233(2), p. 467 (in Russian).
