Dataset - Frequent but Predictable Droughts in East Africa Driven By A Walker Circulation Intensification

The decline of the eastern East African (EA) March-April-May (MAM) rains poses a life-threatening ‘enigma’, an enigma linked to sequential droughts in the most food insecure region in the world. The MAM 2022 drought was the driest on record, preceded by three poor rainy seasons, and followed by widespread starvation. Connecting these droughts is an interaction between La Niña and climate change, an interaction that provides exciting opportunities for long lead prediction and proactive disaster risk management. Using observations, reanalyses, and climate change simulations, we show here, for the first time, that post-1997 OND La Niña events are robust precursors of: (1) strong MAM ‘Western V Gradients’ in the Pacific, which help produce (2) large increases in moisture convergence and atmospheric heating near Indonesia, which appear associated with (3) regional shifts in moisture transports and vertical velocities, which (4) help explain more frequent dry EA rainy seasons. Understanding t..., This dataset was created to support the paper 'Frequent but Predictable Droughts in East Africa Driven By A Walker Circulation Intensification'. This analysis draws together data from six categories:   1. Observed gridded rainfall values  2. Observed sea surface temperatures (SST)  3. Climate change simulations of SST time series  4. Seasonal predictions of SST time series  5. ERA5 atmospheric reanalysis fields  6. MERRA2 atmospheric reanalysis fields Rainfall comes from the Climate Hazard Center Infrared Precipitation with Stations archive (CHIRPS, https://www.nature.com/articles/sdata201566) and Centennial Trends (https://www.nature.com/articles/sdata201550) archives. The observed SST data are from the NOAA Extended Reconstruction sea surface temperature data set (version 5). The seasonal SST forecasts from the North American Multi-Model Ensemble (NMME). The projected SST and precipitation simulation time-series are from Phase 6 of the Climate Model Intercomparison Proje..., By design, no special software or programming expertise is required to access the spreadsheet containing our results.    Â