KlimaCampus Kolloquium: The Polar Oceans and Atmospheric CO2

Gerald H. Haug, Anja Studer, Alfredo Martinez-Garcia (Mainz), Samuel L. Jaccard (Bern), Ralf Tiedemann (Bremerhaven), and Abby Ren, Daniel M. Sigman (Princeton)

We argue for a pervasive link between cold climates and polar ocean stratification (Haug et al., 1999; Sigman et al., 2004, 2007). In both the Subarctic North Pacific and the Antarctic Zone of the Southern Ocean, ice ages were marked by low productivity (Figs. 1 and 2, Jaccard et al. 2010, 2013). The accumulated evidence from sediment cores points to an increase in density stratification that reduced the supply of nutrients from the ocean interior into the sunlit surface in both of these regions. The last ice age was associated with stratification of the Antarctic and the subarctic North Pacific and it can be argued that the well-known glacial decrease in North Atlantic Deep Water indicates a similar stratification of the North Atlantic. This link also applies to longer time scales, including the onset of extensive northern hemisphere glaciation 2.7 million years ago, which was concurrent with stratification of the Subarctic North Pacific and the Southern Ocean. The generality of the cooling/stratification connection calls for a general mechanism.

Datum

02.02.2017

Uhrzeit

15:15 Uhr

Ort

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

Referent

Gerald Haug, MPI for Chemistry

Chair

Bjorn Stevens
Kay Emeis

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