Read here. In a new peer-reviewed study, Russian scientists confirmed that floodplain areas were more widely populated during periods of lesser precipitation (snow and rain). These lesser precipitation regimes occurred during warming periods, with the Medieval Warming being the most significant, not the current warming.
"In a study of the Upper Volga and Zapadnaya Dvina Rivers of Russia, Panin and Nefedov documented "the geomorphological and altitudinal positions of [human] occupational layers corresponding to 1224 colonization epochs at 870 archaeological sites in river valleys and lake depressions in southwestern Tver province,".....The two Russian researchers report finding that "low-water epochs coincide with epochs of relative warming, while high-water epochs [coincide] with cooling epochs," because "during the climate warming epochs, a decrease in duration and severity of winters should have resulted in a drop in snow cover water equivalent by the snowmelt period, a decrease in water discharge and flood stage, and a decrease in seasonal peaks in lake levels,".....And this relationship clearly implies that the current level of warmth in the portion of Russia that hosts the Upper Volga and Zapadnaya Dvina Rivers is not yet as great as it was during the AD 1000-1300 portion of the Medieval Warm Period."