Potential impact of 1.5 °C and 2 °C global warming on consecutive dry and wet days over West Africa
Environmental Research Letters
The southern African climate under 1.5 °C and 2 °C of global warming as simulated by CORDEX regional climate models G Maúre et al -This content was downloaded from IP address 22.214.171.124 on 05/06/2018 at 09:09 Environ. Res. Lett. 13 (2018) 055013 Abstract We examine the impact of +1.5 • C and +2 • C global warming levels above pre-industrial levels on consecutive dry days (CDD) and consecutive wet days (CWD), two key indicators for extreme precipitation and seasonal drought. This is done
... . This is done using climate projections from a multi-model ensemble of 25 regional climate model (RCM) simulations. The RCMs take boundary conditions from ten global climate models (GCMs) under the RCP8.5 scenario. We define CDD as the maximum number of consecutive days with rainfall amount less than 1 mm and CWD as the maximum number of consecutive days with rainfall amount more than 1 mm. The differences in model representations of the change in CDD and CWD, at 1.5 • C and 2 • C global warming, and based on the control period 1971−2000 are reported. The models agree on a noticeable response to both 1.5 • C and 2 • C warming for each index. Enhanced warming results in a reduction in mean rainfall across the region. More than 80% of ensemble members agree that CDD will increase over the Guinea Coast, in tandem with a projected decrease in CWD at both 1.5 • C and 2 • C global warming levels. These projected changes may influence already fragile ecosystems and agriculture in the region, both of which are strongly affected by mean rainfall and the length of wet and dry periods.