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Title: The role of carbonaceous aerosols on short-term variations of precipitation over North Africa

Abstract

Northern Africa has been subject to extensive droughts in the late 20th century, which are frequently linked to changes in the Sea Surface Temperature (SST) in both the Atlantic and Indian Oceans. However, climate models forced by observed Sea Surface Temperatures have been unable to reproduce the magnitude of rainfall reduction over the last several decades. In this study, we propose that aerosol indirect effects (AIE) may be an important feedback mechanism to contribute this recent reduction. The climate model used here has a fully predictive aerosol life cycle. Results are presented for a set of sensitivity experiments designed to distinguish the role of aerosol direct/semi-­direct and indirect effects on regional precipitation. Changes in cloud lifetime due to the presence of carbonaceous aerosols are proposed as a key mechanism to explain the reduced rainfall over the tropical and North Africa.

Authors:
ORCiD logo [1];  [2];  [2];  [3];  [4]
  1. Gwangju Institute of Science and Technology, Gwangju (South Korea)
  2. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  3. Indian Institute of Technology Bhubaneswar, Odisha (India)
  4. Indian Institute of Technology Delhi, New Delhi (India)
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1324911
Report Number(s):
PNNL-SA-88624
Journal ID: ISSN 1530-261X; KP1703020
Grant/Contract Number:
AC05-76RL01830
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Atmospheric Science Letters
Additional Journal Information:
Journal Volume: 17; Journal Issue: 7; Journal ID: ISSN 1530-261X
Publisher:
Royal Meteorological Society
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 58 GEOSCIENCES; role; carbonaceous; aerosols; short-term; variations; precipitation; North Africa; Sahel rainfall; aerosol indirect effect; cloud lifetime effect

Citation Formats

Yoon, Jin -Ho, Rasch, Philip J., Wang, Hailong, Vinoj, V., and Ganguly, Dilip. The role of carbonaceous aerosols on short-term variations of precipitation over North Africa. United States: N. p., 2016. Web. doi:10.1002/asl.672.
Yoon, Jin -Ho, Rasch, Philip J., Wang, Hailong, Vinoj, V., & Ganguly, Dilip. The role of carbonaceous aerosols on short-term variations of precipitation over North Africa. United States. doi:10.1002/asl.672.
Yoon, Jin -Ho, Rasch, Philip J., Wang, Hailong, Vinoj, V., and Ganguly, Dilip. 2016. "The role of carbonaceous aerosols on short-term variations of precipitation over North Africa". United States. doi:10.1002/asl.672. https://www.osti.gov/servlets/purl/1324911.
@article{osti_1324911,
title = {The role of carbonaceous aerosols on short-term variations of precipitation over North Africa},
author = {Yoon, Jin -Ho and Rasch, Philip J. and Wang, Hailong and Vinoj, V. and Ganguly, Dilip},
abstractNote = {Northern Africa has been subject to extensive droughts in the late 20th century, which are frequently linked to changes in the Sea Surface Temperature (SST) in both the Atlantic and Indian Oceans. However, climate models forced by observed Sea Surface Temperatures have been unable to reproduce the magnitude of rainfall reduction over the last several decades. In this study, we propose that aerosol indirect effects (AIE) may be an important feedback mechanism to contribute this recent reduction. The climate model used here has a fully predictive aerosol life cycle. Results are presented for a set of sensitivity experiments designed to distinguish the role of aerosol direct/semi-­direct and indirect effects on regional precipitation. Changes in cloud lifetime due to the presence of carbonaceous aerosols are proposed as a key mechanism to explain the reduced rainfall over the tropical and North Africa.},
doi = {10.1002/asl.672},
journal = {Atmospheric Science Letters},
number = 7,
volume = 17,
place = {United States},
year = 2016,
month = 6
}

Journal Article:
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