Rainfall trends in the African Sahel: Characteristics, processes, and causes

Michela Biasutti

doi:10.1002/wcc.591

journal article Open Access Jun 04, 2019

Rainfall trends in the African Sahel: Characteristics, processes, and causes

Michela Biasutti

WIREs Climate Change Vol. 10 No. 4 · Wiley

View at Publisher Save 10.1002/wcc.591

Abstract

AbstractSahel rainfall is dynamically linked to the global Hadley cell and to the regional monsoon circulation. It is therefore susceptible to forcings from remote oceans and regional land alike. Warming of the oceans enhances the stability of the tropical atmosphere and weakens deep ascent in the Hadley circulation. Warming of the Sahara and of the nearby oceans changes the structure and position of the regional shallow circulation and allows more of the intense convective systems that determine seasonal rain accumulation. These processes can explain the observed interannual to multidecadal variability. Sea surface temperature anomalies were the dominant forcing of the drought of the 1970s and 1980s. In most recent decades, seasonal rainfall amounts have partially recovered, but rainy season characteristics have changed: rainfall is more intense and intermittent and wetting is concentrated in the late rainy season and away from the west coast. Similar subseasonal and subregional differences in rainfall trends characterize the simulated response to increased greenhouse gases, suggesting an anthropogenic influence. While uncertainty in future projections remains, confidence in them is encouraged by the recognition that seasonal mean rainfall depends on large‐scale drivers of atmospheric circulations that are well resolved by current climate models. Nevertheless, observational and modeling efforts are needed to provide more refined projections of rainfall changes, expanding beyond total accumulation to metrics of intraseasonal characteristics and risk of extreme events, and coordination between climate scientists and stakeholders is needed to generate relevant information that is useful even under deep uncertainty.This article is categorized under:
Paleoclimates and Current Trends > Modern Climate Change

Topics

No keywords indexed for this article. Browse by subject →

References

159

[1]

10.1175/jcli-d-11-00019.1

[2]

10.1002/joc.1832

[3]

10.1007/s00382-014-2056-1

[4]

10.1029/2003gl018426

[5]

10.1175/jcli4020.1

[6]

10.1002/2017gl073851

[7]

10.1007/s40641-018-0095-0

[8]

10.1002/2016gl071921

[9]

10.1002/2017wr020970

[10]

10.1038/nclimate1151

[11]

10.1002/jgrd.50206

[12]

10.1029/2006gl026067

[13]

10.1175/2007jcli1896.1

[14]

10.1029/2009gl041303

[15]

10.1175/2009jcli2969.1

[16]

10.1038/s41561-018-0137-1

[17]

10.1175/jcli-d-13-00650.1

[18]

10.1007/s00382-016-3252-y

[19]

10.1038/nature10946

[20]

10.1038/s41559-017-0081

[21]

10.1175/1520-0442(2004)017<1517:rbwvpa>2.0.co;2

[22]

10.1175/1520-0442(1993)006<1077:eocpr>2.0.co;2

[23]

10.1038/nclimate2805

[24]

10.1002/qj.49710142802

[25]

10.1029/2003pa000916

[26]

10.1175/1520-0442(2004)017<2688:mogwio>2.0.co;2

[27]

10.1126/science.aab3980

[28]

10.1002/2017gl074622

[29]

10.1038/s41558-017-0059-8

[30]

10.1002/qj.414

[31]

10.1175/jcli-d-15-0664.1

[32]

10.1007/s00382-014-2120-x

[33]

The recent Sahel drought is real

Aiguo Dai, Peter J. Lamb, Kevin E. Trenberth et al.

International Journal of Climatology 10.1002/joc.1083

[34]

10.1016/j.rse.2013.09.011

[35]

10.1080/17565529.2017.1405784

[36]

10.1175/jcli-d-12-00467.1

[37]

10.1175/jcli-d-14-00039.1

[38]

10.1029/2007jd008470

[39]

FCFA. (2017). Future climate For Africa. Retrieved fromfutureclimateafrica.org.

[40]

10.1029/2002jd002816

[41]

10.1175/mwr3182.1

[42]

10.1002/2014jd022365

[43]

10.1038/320602a0

[44]

10.1007/s00382-016-3146-z

[45]

GFDRR. (2015).Strengthening climate and disaster resilience in Sub‐Saharan Africa. Retrieved fromgfdrr.org

[46]

10.1175/2009jcli3123.1

[47]

10.1007/s10584-008-9396-y

[48]

10.1088/1748-9326/8/2/024010

[49]

10.1126/science.1089357

[50]

10.1029/2007jd008972

Showing 50 of 159 references

Cited By

221

The Saharan Desert: Climate, Terrain and Contemporary Perspectives

P. C. Moharana · 2026

Annals of Arid Zone

Influence of Barents Sea Ice in May on the West African Summer Monsoon and its possible mechanisms

Aminu Dalhatu Datti, Gang Zeng · 2026

Atmospheric Research

Trend and Variability Analysis of Rainfall and Temperature in the Dagona Wetland, Nigeria (1993-2023)

Yusuf Ibrahim, Abubakar Sani Bawale · 2026

UMYU Scientifica

Physiological, metabolomic, morphological and root system architecture acclimation responses to drought in the African orphan millet white fonio (Digitaria exilis)

Roshan Pudasaini, Joy Amyotte · 2025

Plant and Soil

Notable shifts beyond pre-industrial streamflow and soil moisture conditions transgress the planetary boundary for freshwater change

Miina Porkka, Vili Virkki · 2024

Nature Water

Mechanisms and Impacts of Earth System Tipping Elements

Seaver Wang, Adrianna Foster · 2023

Reviews of Geophysics

Spatially explicit risk mapping reveals direct anthropogenic impacts on migratory birds

Claire Buchan, Aldina M. A. Franco · 2022

Global Ecology and Biogeography

Evidence of anthropogenic impacts on global drought frequency, duration, and intensity

Felicia Chiang, Omid Mazdiyasni · 2021

Nature Communications

Rainfall Variability and Trend Analysis of Rainfall in West Africa (Senegal, Mauritania, Burkina Faso)

Zeineddine Nouaceur, Ovidiu Murarescu · 2020

Water

Spatial and Temporal Changes in the Normalized Difference Vegetation Index and Their Driving Factors in the Desert/Grassland Biome Transition Zone of the Sahel Region of Africa

Shupu Wu, Xin Gao · 2020

Remote Sensing

Metrics

221

Citations

159

References

Details

Published: Jun 04, 2019
Vol/Issue: 10(4)
License: View

Authors

M

Michela Biasutti

Lamont‐Doherty Earth Observatory Columbia University Palisades New York

Funding

National Aeronautics and Space Administration Award: NNX16AN29G

Division of Atmospheric and Geospace Sciences Award: 1612904

U.S. Department of Energy Award: DE‐SC0014423

Cite This Article

Michela Biasutti (2019). Rainfall trends in the African Sahel: Characteristics, processes, and causes. WIREs Climate Change, 10(4). https://doi.org/10.1002/wcc.591

Rainfall trends in the African Sahel: Characteristics, processes, and causes

You May Also Like