Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling
28 May 2020

Projected Changes in the Terrestrial and Oceanic Regulators of Climate Variability Across Sub-Saharan Africa

Projected Changes in the Regulators of Climate Variability Across Sub-Saharan Africa

Science

The present study focuses on projected responses to the enhanced greenhouse effect in (1) the mean state of the atmosphere and land surface; (2) oceanic and terrestrial drivers of sub-Saharan climate variability; and (3) total seasonal climate predictability of sub-Saharan Africa.  Analysis, based on output from 23 Earth System Models in the Coupled Model Intercomparison Project Phase Five for the late 20th and 21st centuries.

Impact

The general model consensus of future projections indicates diminished seasonal predictability of sub-Saharan African regional climate based on key oceanic and terrestrial predictors and an elevated role of the land surface (associated with soil moisture anomalies) compared to oceanic drivers in regulating regional climate variability.

Summary

Future changes in the sign and intensity of ocean-land-atmosphere interactions have been insufficiently studied, despite implications for regional climate change projections, extreme event statistics, and seasonal climate predictability.  The present study focuses on projected responses to the enhanced greenhouse effect in (1) the mean state of the atmosphere and land surface; (2) oceanic and terrestrial drivers of sub-Saharan climate variability; and (3) total seasonal climate predictability of sub-Saharan Africa.  Analysis, using the Stepwise Generalized Equilibrium Feedback Assessment (SGEFA), focuses on output from 23 Earth System Models in the Coupled Model Intercomparison Project Phase Five for the late 20th and 21st centuries.  It is projected that the greatest warming across sub-Saharan Africa will occur over the Sahel, the monsoon season will become more persistent into late summer and autumn, short rains in the Horn of Africa (HOA) will intensify, and leaf area index will increase across the HOA. The models indicate that the study region’s climate variability is dominated by oceanic drivers, with secondary contributions from soil moisture and very modest impacts from vegetation. The general model consensus of future projections indicates diminished seasonal predictability of sub-Saharan African regional climate based on key oceanic and terrestrial predictors and an elevated role of the land surface (associated with soil moisture anomalies) compared to oceanic drivers in regulating regional climate variability.

Contact
Michael Notaro
University of Wisconsin - Madison
Publications
Notaro, M, F Wang, Y Yu, and J Mao.  2020.  "Projected Changes in the Terrestrial and Oceanic Regulators of Climate Variability Across Sub-Saharan Africa."  Climate Dynamics.