MEDITERRANEAN VEGETATION, LAKE LEVELS AND PALEOCLIMATE AT THE LAST GLACIAL MAXIMUM
Résumé
THE apparent conflict between pollen evidence for widespread Artemisia steppe1-6 (implying semi-arid conditions) and geomorphological evidence for high lake levels4,7-11 has produced controversy about the ice-age palaeoclimate of the Mediterranean region. Here we use a water-balance model12 (to predict catchment runoff ) and a biome model13 (to predict vegetation type) to reconstruct the palaeoenvironment around Lake Ioannina-a type locality for the northern Mediterranean region. We show that both sets of evidence are compatible with a summer-dry, winter-wet regime with seasonal temperature anomalies similar to those predicted by atmospheric model simulations of the Last Glacial Maximum14-18. The drying effect of the cold North Atlantic Ocean may have been counteracted in winter by increased storm frequency under a southward-shifted jet stream, as shown by several atmospheric models16-18.