ИСТИНА

Abstract: We obtained a temporal variability of UV erythemal radiation (UVery) and UV resources over Northern Eurasia for the 1979-2015 period on the basis of the ERA-INTERIM reanalysis, TOMS and OMI satellite data with new aerosol correction, and the results of numerical experiments using a chemistry climate INM-RSHU model. Implementing the aerosol correction for satellite measurements was carried out according to the updated Macv2 aerosol dataset (Kinne et al., 2013). A statistically significant positive UVery trend up to 2.5% per decade due to the reduction of ozone in the spring and summer periods was obtained for European territory and 3% per decade - for the regions of Central Siberia (the Baikal region) according to both satellite data and ERA-INTERIM datasets. In addition, for several regions a statistically significant positive UVery trend in cloud transmittance of up to 6-8% per decade was revealed. The account for both ozone and cloud factors provides positive UVery trend of about 6-9% per decade over Eastern Europe, some regions of Siberia and the Far East in the spring and summer and negative trend in July over some Arctic area. These temporal changes agree well with the estimated UVery trend over Moscow. Model experiments with INM-RSHU chemical-climate model has revealed that the anthropogenic emissions of ozone-depleting substances have the greatest impact on the variability of ozone and, hence, UVery. Among the natural factors, volcanic aerosol as well as sea surface temperature and sea ice coverage play also an important role. We observe a noticeable UV growth which is mainly translated in increase of occurrence of the extreme category of UV resources except Arctic regions where during summer time there is a slight increase of the zone with UV-optimum conditions for the 2 and 3 skin types.