Ice sheet decline and rising atmospheric CO2 control AMOC sensitivity to deglacial meltwater discharge
نویسندگان
چکیده
The last deglaciation was characterized by a sequence of abrupt climate events thought to be linked rapid changes in Atlantic meridional overturning circulation (AMOC). includes weakening the AMOC after Last Glacial Maximum (LGM) during Heinrich Stadial 1 (HS1), which ends with an amplification at transition Bølling/Allerød (B/A). This occurs despite persistent deglacial meltwater fluxes that counteract vigorous North deep-water formation. Using Earth system model COSMOS range boundary conditions and reconstructed fluxes, we show CO2 rise ice sheet decline modulate sensitivity these fluxes. While declining sheets increase sensitivity, increasing atmospheric levels tend this effect. Therefore, occurrence weaker HS1 presence meltwater, might explained effects, as alternative or combination magnitude routing discharge.
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ژورنال
عنوان ژورنال: Global and Planetary Change
سال: 2022
ISSN: ['0921-8181', '1872-6364']
DOI: https://doi.org/10.1016/j.gloplacha.2022.103755