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Global and regional importance of the direct dust-climate feedback.

ABSTRACT: Feedbacks between the global dust cycle and the climate system might have amplified past climate changes. Yet, it remains unclear what role the dust-climate feedback will play in future anthropogenic climate change. Here, we estimate the direct dust-climate feedback, arising from changes in the dust direct radiative effect (DRE), using a simple theoretical framework that combines constraints on the dust DRE with a series of climate model results. We find that the direct dust-climate feedback is likely in the range of -0.04 to +0.02?Wm?-2?K-1, such that it could account for a substantial fraction of the total aerosol feedbacks in the climate system. On a regional scale, the direct dust-climate feedback is enhanced by approximately an order of magnitude close to major source regions. This suggests that it could play an important role in shaping the future climates of Northern Africa, the Sahel, the Mediterranean region, the Middle East, and Central Asia.

SUBMITTER: Kok JF

PROVIDER: S-EPMC5770443 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Global and regional importance of the direct dust-climate feedback.

Kok Jasper F JF Ward Daniel S DS Mahowald Natalie M NM Evan Amato T AT

Nature communications 20180116 1

Feedbacks between the global dust cycle and the climate system might have amplified past climate changes. Yet, it remains unclear what role the dust-climate feedback will play in future anthropogenic climate change. Here, we estimate the direct dust-climate feedback, arising from changes in the dust direct radiative effect (DRE), using a simple theoretical framework that combines constraints on the dust DRE with a series of climate model results. We find that the direct dust-climate feedback is ...[more]

PMID: 29339783

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