Tropical impacts on Mediterranean climate variability (already finished)

Start date: 01.01.2006
Duration: 2 years
Funded by: Promotionsstipendium der Studienstiftung des deutschen Volkes
Local project leader: Prof. Dr. J. Jacobeit


Analysing tropical impacts on Mediterranean climate variability is the general aim of this recent project. The focus on the Mediterranean region results from its character as a key region in a particular way: regional climate processes not only reflect variability of both, extratropical and tropical circulation, but also the effects of their interactions and particular teleconnections like the impacts of the Asian monsoon or the El-Niño-Southern-Oscillation on Mediterranean climate. The recently started MedCLIVAR (Mediterranen climate variability and predictability) programme under the umbrella of the international research project CLIVAR (Climate Variability and Predictability) shows the increasing efforts for a better understanding of Mediterranean climate and circulation dynamics. In this context requirements for future research are mentioned which induced the scientific development of this project.

First a teleconnection analysis of Mediterranen precipitation fields will provide indications of tropical impacts on Mediterranean precipitation variability. Particularly teleconnections with the Asian and African monsoon systems will be taken into account. For this purpose statistical methods like correlation analysis, multiple regression and canonical correlation analyses will be applied. In a second step the role of tropical-extratropical interactions in affecting Mediterranean precipitation variability in terms of heavy rain events and thunderstorms will be highlighted. For instance, applying Extended PCA on atmospheric pressure fields accompanying extreme precipitation events should give a better insight into circulation dynamics as a reason for their occurrence. The results of both steps have to be compared and evaluated for substantial agreements. Whether teleconnection analyses are able to identify tropical-extratropical interactions will be an interesting aspect concerning methodological discussions.