CLIMATE AND SOCIETAL CHANGES IN THE MEDITERRANEAN FROM THE LATE GLACIAL TO THE MIDDLE HOLOCENE

Climatic stress often pushed societies to develop new technologies or to move to a new location. Additionally, people are often pulled towards more attractive sites where resources may be more widely available. It has been hypothesized that the development and spread of agriculture in the Levant may have been related to abrupt climate change at the end of the late Glacial. Before this theory can be tested, the extent and duration of the climatic events must be determined. With this in mind, cores collected from the Mediterranean Basin and stored at the Lamont Doherty Earth Observatory core repository were selected and sampled at high resolution. Samples were analyzed to precisely assess the duration, magnitude, and extent of the Younger Dryas, the 8,200 cal yr event, and other sharp climatic events in the late Glacial and early Holocene.

The top of the two cores analyzed so far (RC9-185 from the Eastern Ionian Sea and RC9-195 from the Tyrrhenian Sea) are warmer than the base of the cores as indicated by an increase in warm water species and a decrease in cold water species (e.g. N. pachyderma). Species assemblages from these cores indicate a general warming pattern throughout the Holocene. In addition, preliminary results of oxygen isotope analysis on single specimens of G. ruber, G. bulloides, and G. inflata indicate 3-4 abrupt climatic shifts. Although AMS dating has not yet been performed on these cores, the data indicate that the cores cover the late Glacial to mid-Holocene interval as suggested during sampling by the presence of known tephra layers. Faunal and isotopic analyses are supplemented by the analysis of clay mineral assemblages from the cores.