MEDiterranean surface HYdrology during abrupt climatic events (MEDHY)
Temperature anomalies associated with abrupt climatic events are well described in Northern Atlantic records during the last glacial. However, there is a crucial need of reliable quantitative reconstitution of temperature from all other the world, since the spread of this temperature signal is not well documented, especially on continents and/or at mid-latitudes. A first step towards a better understanding of the physical mechanisms that tightly link high and low latitudes is the gain of sufficiently resolved continental temperature and precipitation records.
However, temperature reconstructions in the continental realm remain a challenging issue. Recently, a new group of membrane lipids, the GDGTs, produced by an as yet unknown group of anaerobic soil bacteria was proposed as a composite proxy of Mean Annual Temperature (MAT) and soil pH. Revisiting sedimentary archives, in the Mediterranean area, that have proven their reliability using a set of paleoclimatic markers of surface hydrology could improve the present knowledge of thermal evolution on continents. We therefore plan to couple recently developed continental temperature proxies based on organic biomarkers with more classical proxies of continental temperature and runoff. The “MEDHY” project addresses issues covered by « WP1. Understanding and evaluating Mediterranean climatic changes and natural hazards ».
The project is divided into three axes and three locations along a west-east and a continental/marine gradients :
Axe 1: Abrupt continental temperature changes during the last glacial: new results from “old” lacustrine sequences, lakes du Bouchet and Les Echets (France) - independently developed and co-funded via the ECCOREV call for project.
Axe 2: Reconstruction of the continental temperatures and precipitation on the last glacial cycle from a continental margin: new results from PROMESS drilling
Axe 3: Reconstruction of surface hydrology from the Eastern boundary of the Mediterranean basin: case of the MD042722