TY - JOUR T1 - Sahel Rainfall Projections Constrained by Past Sensitivity to Global Warming AU - Schewe, Jacob AU - Levermann, Anders Y1 - 2022/09/28 PY - 2022 DA - 2022/09/28 N1 - https://doi.org/10.1029/2022GL098286 DO - https://doi.org/10.1029/2022GL098286 T2 - Geophysical Research Letters JF - Geophysical Research Letters JO - Geophysical Research Letters JA - Geophys Res Lett SP - e2022GL098286 VL - 49 IS - 18 PB - John Wiley & Sons, Ltd SN - 0094-8276 M3 - https://doi.org/10.1029/2022GL098286 UR - https://doi.org/10.1029/2022GL098286 Y2 - 2022/09/21 N2 - Abstract Africa's central Sahel region has experienced prolonged drought conditions in the past, while rainfall has recovered more recently. Global climate models project anything from no change to a strong wetting trend under unabated climate change; and they have difficulty reproducing the complex historical record. Here we show that when a period of dominant aerosol forcing is excluded, a consistent wetting response to greenhouse-gas induced warming emerges in observed rainfall. Using the observed response coefficient estimate as a constraint, we find that Coupled Model Intercomparison Project Phase 6 climate models with a realistic past rainfall response show a smaller spread, and higher median, of projected future rainfall change, compared to the full ensemble. In particular, very small or negative rainfall trends are absent from the constrained ensemble. Our results provide further evidence for a robust Sahel rainfall increase in response to greenhouse-gas forcing, consistent with recent observations, and including the possibility of a very strong increase. ER -