Ocean Circulation and Climate Dynamics

Tectonics and ocean-land interactions

Paleogeographic changes in the geological past have led to fundamental shifts in ocean circulation as well as regional and global climate. Variations in ocean currents caused massive changes in the transport of warmth and moisture and influenced the distribution of precipitation and weathering intensity on land. This led to, for example, a much warmer, and likely ice-free, climate during the Cretaceous. The most important tectonic changes that impacted the climate during the past 60 million years were the opening of the Tasman Sea and the Drake Passage 30-40 million years ago, the opening of the Fram Strait 17.5 million years ago and the progressive closure of the Indonesian Throughflow and the Tethys Sea, as well as the closure of the Central American Seaway around 3 million years ago.

Research at GEOMAR investigates the global climate and the interaction between land and ocean under different tectonic and climatic conditions. At the forefront are marine proxy records that are produced at different time scales to determine the exact timing and sequence of tectonic processes and their impacts on ocean circulation and climate.

Late Miocene to Pliocene narrowing of the Indonesian ocean passage
The closure of the Central American Seaway