Joint Seminar: Modeling Mediterranean Ocean Climate for the LGM and the Early Holocene

Recent results from a working group investigating past climates of the Mediterranean are presented.  A regional ocean model of the Mediterranean is used to simulate past climate variations in the Mediterranean. The model is forced with atmospheric forcing derived from steady state simulations with an earth system model.

For the Last Glacial Maximum, the model is essentially able to reproduce the pattern of SST anomalies reconstructed from assemblages of foraminifera. These anomalies are characterized by a strong cooling in the northwestern Mediterranean (strongest in summer) and a moderate cooling in the Levantine. The lower sea level leads to reduced exchange across the sills resulting in an enhanced salinity gradient to the Atlantic in spite of reduced net evaporation.

The early Holocene is characterized by the presence of oxygen depleted deep waters in the eastern Mediterranean. One obvious cause could be the presence of stagnating deep waters. The model is used to assess the effectivity of several potential mechanisms to decrease or entirely suppress deep water formation in the eastern Mediterranean. This includes enhanced run off from the Nile and the onset of a potential outflow from the Black Sea.

A model version with interactive marine biogeochemistry model is used to estimate the effect of enhanced riverine nutrient input and stagnating deep water on the biogeochemistry of the Mediterranean.

Datum

14.06.2011

Uhrzeit

15:15 Uhr

Ort

Bundesstr. 53, room 022/023
Seminar Room 022/023, Ground Floor, Bundesstrasse 53, 20146 Hamburg, Hamburg

ReferentIn

Uwe Mikolajewicz, MPI-M

Chair

Uwe Mikolajewicz

Zur Übersicht