CLIMATE DYNAMICS, cilt.47, ss.3011-3027, 2016 (SCI-Expanded, Scopus)
The Caucasus region experiences recurrent droughts that affect natural vegetation and the agriculture-based economies of several countries. Because meteorological records are in general scarce and of short timespan, little is known about the magnitude and frequency of past climate variability. Despite therecent increase of climate reconstructions for parts of Eurasia, no study has focused on past hydroclimate variability in the Caucasus. Here, we use a multispecies network of tree-ring width chronologies from the Lesser Caucasus to develop the first precipitation reconstruction for the region back to 1752 CE. Despite the high annual precipitation in the region, our reconstruction accounted for 51.2 % of the variability in May-June precipitation from 1930 to 2001. Incomparison with reconstructions in the eastern Mediterranean, our new reconstruction revealed important and distinct drought periods and pluvials. Previous winter North Atlantic Oscillation (NAO), and spring East Atlantic/Western Russia (EA/WR) and North Sea Caspian patterns are likely key drivers of May-Juneprecipitation in the Caucasus and Anatolia. NAO appeared to negatively affect rainfall low-frequency variability while effects of EA/WR were more apparent at the interannual timescales. We also show a potential positive effect of Black Sea surface temperatures on May-June precipitation. In the Caucasus, May-June represents the period of major water supply in semi-arid areas and the period with the highest potential of water scarcity in mesic areas. It is also a period of potential catastrophic flood events. Thus, changes to the precipitation regime during this season will be critical to both human and natural systems of the Caucasus region.