The focus of our research in this area is on understanding the role of the North Atlantic and global ocean in the climate system, which includes next to the ocean, the atmosphere, the cryosphere and partly the geosphere.
Decadal climate variability
Work is based on data analyses and model calculation, individually and in combination. Investigated are variations of the ocean circulation and interactions with single components of the climate system on seasonal up to decadal time scales. One aim of this work is to achieve an improved prediction of decadal climate oscillations in the North Atlantic area by initializing coupled climate models with climate observations. Such predictions can provide information about upcoming changes in ocean heat transport and hence about changes in temperature over northern Europe. In addition to that, long time series measurements on key positions of the interrelated North Atlantic – Norwegian Sea – Arctic Ocean are conducted on an international scale. Model simulations are improved with these time series, which are needed for a realistic predictability of the coupled climate system. The same applies to the coupling between the Norwegian Sea and the North Atlantic as well as for the coupling between the North Sea and the North Atlantic. Here, a key aspect is the improvement of ocean parameterizations, e.g. of mixing and vorticity fluxes as well as the impact of small-scale circulation oscillations on the biology and biogeochemistry. The enhancement and expanded usage of satellite data for the investigation of the ocean, sea ice and the climate system as well as the joint data syntheses with in-situ measurements, ocean and climate models are central work areas of the Institute of Oceanography.
Achievement of significant, decadal predictions is an overarching goal of the ‚World Climate Research Program’ (WCRP) for the next years. In this context, the institute participates in BMBF-funded cluster projects such as RACE and MiKLIP. It also contributes to programs that investigate the role of the ocean as an ecological system, e.g. SOPRAN. Here, investigations focus on the influence of Sahara dust on the ocean, the estimation of carbon fluxes between ocean and atmosphere, the vertical matter transport of solved and particular matter from the euphotic zone to the deep oceans, the exchange processes with the sea floor and the lateral shelf seas as well as the impact of physical movements on plankton and higher trophic levels, especially on the recruitment of fish. Apart from that, an important issue are interactions between the physical circulation and biosphere and the role of the ocean in the global nutrition and carbon storage.
Observations of sea surface height and sea ice form the thematic priority of climate-related satellite data analyses. Studies of mass shifts in the ocean, analyses of sea surface salinity from satellite measurements and the investigation of oscillations in the polar ice cover and thickness, from e.g. Cryosat measurements, belong to these analyses. All this scientific work serves the analysis of regional and global ocean circulation changes and contributes to the understanding of the global water cycle.
Written by Prof Dr. Detlef Stammer