Tropical Pacific climate impacts of a collapsed Atlantic Meridional Overturning Circulation
Abstract
Past climatic states have been characterized by a collapsed Atlantic Meridional Overturning Circulation (AMOC), and there is evidence of an AMOC slowdown in todays climate. Future climate projections suggest further weakening and potential collapse of the AMOC under global warming even when contemporary climate models neglect meltwater input from Greenland. These AMOC changes could have significant ramifications for Atlantic heat transport, Arctic sea-ice coverage and regional climate. However, it remains unclear how an AMOC shutdown might impact other regions of the globe. Here we use a global climate model to show how an AMOC collapse can modify the Pacific trade winds and accelerate the Walker circulation by virtue of the altered heat transport and an Atlantic-Pacific teleconnection. These changes have consequences for the tropical Pacific mean state which are found to alter the governing El Nino Southern Oscillation (ENSO) feedbacks, damping its growth rate and decreasing its variability.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFMOS41B..01O