Millennial to orbital-scale variations of drought intensity in the Eastern Mediterranean. (1st February 2016) - Stockhecke, Mona
Abstract: Millennial to orbital-scale rainfall changes in the Mediterranean region and corresponding variations in vegetation patterns were the result of large-scale atmospheric reorganizations. In spite of recent efforts to reconstruct this variability using a range of proxy archives, the underlying physical mechanisms have remained elusive. Through the analysis of a new high-resolution sedimentary section from Lake Van (Turkey) along with climate modeling experiments, we identify massive droughts in the Eastern Mediterranean for the past four glacial cycles, which have a pervasive link with known intervals of enhanced North Atlantic glacial iceberg calving, weaker Atlantic Meridional Overturning Circulation and Dansgaard-Oeschger cold conditions. On orbital timescales, the topographic effect of large Northern Hemisphere ice sheets and periods with minimum insolation seasonality further exacerbated drought intensities by suppressing both summer and winter precipitation. Graphical abstract: Highlights: Eastern Mediterranean climate reconstruction of Dansgaard-Oeschger variability over 360 k. Lake Van multi-proxy hydroclimate index correlates well with transient LOVECLIM simulations. Droughts in the EM for the past three glacial cycles show a pervasive link with DO stadials. North Atlantic stadials generate anticyclonic circulation anomaly over EM. NH ice sheets exacerbated large-scale glacial drying in the EM.