The 8.2 kyr BP event simulated by a global atmosphere-sea-ice-ocean model

• Published in: Geophysical Research Letters
• Main Authors: Renssen, H., Goosse, Hugues, Fichefet, Thierry, Campin, JM.
• Other Authors: UCL - SC/PHYS - Département de physique, UCL - SST/ELI/ELIC - Earth & Climate
• Format: Article in Journal/Newspaper
• Language: English
• Published: Amer Geophysical Union 2001
• Subjects: Labrador Sea; North Atlantic; North atlantic Thermohaline circulation; Sea ice
• Online Access: http://hdl.handle.net/2078.1/42809; https://doi.org/10.1029/2000GL012602

Seven freshwater perturbation experiments were performed with a global atmosphere-sea-ice-ocean model to study the mechanism behind the 8.2 kyr BP Holocene cooling event. These experiments differed in initial state and duration of the applied freshwater pulse, while the amount of freshwater was kept constant (4.67x10(14) m(3)). One of the scenarios, with freshwater added to the Labrador Sea at a rate of 0.75 Sv during 20 years, resulted in weakening of the North Atlantic thermohaline circulation during 320 years and surface cooling varying from 1 to 5 degreesC over adjacent continents. This result is consistent with proxy data, suggesting that a meltwater-induced weakening of the thermohaline circulation caused the event. Moreover, our results indicate that the time-scale of the meltwater release and the initial state are important, as both have a strong effect on the magnitude and duration of the produced model response.