Deutsch
 
Benutzerhandbuch Datenschutzhinweis Impressum Kontakt
  DetailsucheBrowse

Datensatz

DATENSATZ AKTIONENEXPORT

Freigegeben

Zeitschriftenartikel

Heinrich events show two-stage climate response in transient glacial simulations

MPG-Autoren
/persons/resource/persons104729

Ziemen,  Florian
Ocean Physics, The Ocean in the Earth System, MPI for Meteorology, Max Planck Society;

/persons/resource/persons216563

Kapsch,  Marie-Luise
Ocean Physics, The Ocean in the Earth System, MPI for Meteorology, Max Planck Society;

/persons/resource/persons216561

Klockmann,  Marlene
Ocean Physics, The Ocean in the Earth System, MPI for Meteorology, Max Planck Society;

/persons/resource/persons37265

Mikolajewicz,  Uwe
Ocean Physics, The Ocean in the Earth System, MPI for Meteorology, Max Planck Society;

Externe Ressourcen
Es sind keine Externen Ressourcen verfügbar
Volltexte (frei zugänglich)

cp-15-153-2019.pdf
(Verlagsversion), 10MB

Ergänzendes Material (frei zugänglich)

cp-15-153-2019-supplement.pdf
(Ergänzendes Material), 6MB

Zitation

Ziemen, F., Kapsch, M.-L., Klockmann, M., & Mikolajewicz, U. (2019). Heinrich events show two-stage climate response in transient glacial simulations. Climate of the Past, 15, 153-168. doi:10.5194/cp-15-153-2019.


Zitierlink: http://hdl.handle.net/21.11116/0000-0000-AFB5-F
Zusammenfassung
Heinrich events are among the dominant modes of glacial climate variability. During these events, massive iceberg armadas were released by the Laurentide Ice Sheet and sailed across the Atlantic where they melted and released freshwater, as well as detritus, that formed characteristic layers on the seafloor. Heinrich events are known for cold climates in the North Atlantic region and global climate changes. We study these events in a fully coupled complex ice sheet–climate model with synchronous coupling between ice sheets and oceans. The ice discharges occur as an internal variability of the model with a recurrence period of 5kyr, an event duration of 1–1.5kyr, and a peak discharge rate of about 50mSv, roughly consistent with reconstructions. The climate response shows a two-stage behavior, with freshwater release effects dominating the surge phase and ice sheet elevation effects dominating the post-surge phase. As a direct response to the freshwater discharge during the surge phase, deepwater formation in the North Atlantic decreases and the North Atlantic deepwater cell weakens by 3.5Sv. With the reduced oceanic heat transport, the surface temperatures across the North Atlantic decrease, and the associated reduction in evaporation causes a drying in Europe. The ice discharge lowers the surface elevation in the Hudson Bay area and thus leads to increased precipitation and accelerated ice sheet regrowth in the post-surge phase. Furthermore, the jet stream widens to the north, which contributes to a weakening of the subpolar gyre and a continued cooling over Europe even after the ice discharge. This two-stage behavior can explain previously contradicting model results and understandings of Heinrich events.