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<p>West Africa (WA) is prone to food insecurity due to climate-, economic-, conflict-related shocks, as well as high population growth and lack of proper adaptation strategies. As per the USAID’s Famine Early Warning Systems Network, which uses Integrated Phase Classification to classify acute food insecurity (AFI), between 2011 and early 2020, several parts of WA reported the “Stressed” phase of AFI >30% of the time. Food security and livelihood in the region relies substantially on rainfed farming and small-scale water holes. Droughts lead to water deficits resulting in adverse impacts on food production, human and livestock health and agricultural labor opportunities, leading to or worsening of food insecurity. Thus far, the focus of climate, drought outlooks and their impacts, to support food insecurity early warning in this region has mainly been on the seasonal scale (i.e., 3-6 months in future) forecasts whereas use of subseasonal scale (2-4 weeks in future) forecasts has been negligible. Recent advances in routine production (i.e. weekly) and open access to subseasonal forecasts provide an unprecedented opportunity to improve the existing climate services in the region by focusing on the impacts of subseasonal climate characteristics on food insecurity in the region. Here we report on an ongoing project with the AGRiculture HYdrology and METeorology Regional Centre (SERVIR’s WA Hub) that aims to develop a subseasonal water deficit forecasting system to support food insecurity early warning in the region. The presentation will describe  (i) the results of an ongoing analysis examining the influence of subseasonal climate characteristics (e.g. monthly climate variability, length of dry or wet spell) on food insecurity, as measures by different food insecurity indicators (such as vegetation index, food insecurity reports and household level health and malnutrition reports) and (ii) the major accomplishments towards implementation of the water deficit forecasting system, including development and evaluation of prototype products, (iii) capacity building and stakeholder engagement activities with National Meteorological and Hydrological Services across the region. </p>

<p>Early warning of drought is crucial for mitigation of the most adverse impacts of water and food insecurity to lives and livelihoods. Recent advances in routine production (i.e., weekly) and open access to NMME SubX—subseasonal climate forecasts—provide an unprecedented opportunity to improve drought early warning near the onset and middle of the crop-growing season. Near the onset of a season, subseasonal precipitation forecasts have the potential to provide early indication of delay in rain onset, which, as shown in a recent study (Shukla et al., 2021, PLOS ONE), can be a reliable indicator of agricultural drought development. This is particularly relevant for some of the most food-insecure regions in East Africa. Additionally, subseasonal forecasts have the potential to improve drought forecasting during the middle of the season—several months before the harvests—when they are used in combination with to-date observations. Integration of near-real-time observations with subseasonal climate forecasts can enhance drought detection capabilities by leveraging the skill that is derived from initial conditions (as of middle of the season) and complementing it with the skill of subseasonal climate forecasts. Here, we first describe how onset of the rainy season is a reliable indicator of agricultural droughts. The results indicate that in the administrative units in sub-Saharan Africa, which  have the highest risk of acute food insecurity, a delay of about 20 days in the rainy season onset can double the probability of agricultural droughts. We then describe the results of an analysis examining the performance of subseasonal climate forecasts in identifying the timing of the onset of the rainy season in those administrative units. Next, we describe a SERVIR-AST-supported project, which uses subseasonal climate forecasts to develop a West Africa-focused water-deficit forecasting system in collaboration with AGRHYMET, primarily  for agropastoral usage. Here, we make  use of a widely used crop water balance model, the Water Requirement Satisfaction Index (WRSI), to generate improved forecasts of crop water stress, and hence, crop production outcomes, during the middle of the rainy season in West Africa (June through September). We compare the performance of these forecasts with the forecasts generated using climatology only. Finally, we briefly describe how these subseasonal climate forecasting products are being disseminated, communicated, and used in the focus regions.</p>