Can dust drive abrupt climate change?

Monday, 15 December 2014: 10:20 AM
Amy C Clement, Lisa Murphy and Marlos P Goes, University of Miami, Miami, FL, United States
Paleoclimate records from the Atlantic basin have shown that Heinrich events are accompanied by increased dust deposition. We hypothesize that this additional dust in the atmosphere can accelerate the climate changes associated with the Heinrich events. To test this hypothesis, experiments are performed with the Community Earth System Model (CESM) in which we examine the impact of dust, primarily from the African continent, on North Atlantic sea surface temperature, tropical precipitation, and the Atlantic meridional overturning circulation (AMOC). Further sensitivity studies are performed with the UVic earth system climate model to evaluate the mechanisms linking dust radiative forcing and the AMOC. Results show that the additional dust cools the North Atlantic surface and weakens the AMOC. Both of these impacts would accelerate the Heinrich event, implying that, indeed, dust may play a role in driving abrupt climate change in the Atlantic.