Could meltwater pulses have been sneaked unnoticed into the deep ocean during the last glacial?

• Published in: Geophysical Research Letters
• Main Authors: Roche, Didier M., Renssen, Hans, Weber, Susanne, Goosse, Hugues, Roche, Didier
• Other Authors: Vrije Universiteit Amsterdam Amsterdam (VU)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2007
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Arctic; Arctic Ocean; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-03446795; https://hal.archives-ouvertes.fr/hal-03446795/document; https://hal.archives-ouvertes.fr/hal-03446795/file/2007GL032064.pdf; https://doi.org/10.1029/2007gl032064

International audience The lack of climatic imprint left by the Meltwater Pulse-1A ('14.5 ka BP), equivalent to a sea-level rise of 14 to 20 meters, is puzzling. Recent studies suggest the event might have occurred as a hyperpycnal flow in the Gulf of Mexico, preventing its detection in oceanic records throughout the North Atlantic. We present a suite of simulations with the LOVECLIM climate model, which mimic the effect of hyperpycnal flow under LGM conditions, in a first attempt to constrain its climatic effects. Analysing the ocean dynamics associated with the anomalous freshwater input, we show that the proposed mechanism is capable of sneaking a significant proportion of the MWP into the ocean ('6 meters equivalent sea-level rise using our model under LGM boundary conditions). We also demonstrate that, in our model, the meridional circulation is more sensitive to such inputs in the Arctic Ocean than in the Gulf of Mexico.