Overview and Conclusions

Abstract

Sustainable cultures and economies in the East Sahel need to evolve with a strong base at the local community level. In a region where water is such a determining asset, this requires a fundamental adaptation to the constraints that nature itself places on the resource. The greatest, most fundamental, and most immediate threat to the local population is the unpredictable variability of rainfall—the dimensions of which can only be appreciated by understanding the historical record on monthly, annual, and multidecadal time scales. However, due to the specific nature of the dominant type of storm systems in the region, certain essential aspects of rain storm patterns cannot be captured without daily coverage. While most of the rain days have low intensity, most of the annual rainfall total is contributed by the fewer, high-intensity events associated with deep convection into the troposphere. Although the most extreme storms often leave little to no imprint on monthly or annual totals, these are the events that most significantly impact the local landscape and communities. An overarching concern by many is a pessimistic view that climate—namely rainfall—in the East Sahel has degraded significantly over the last decades and is expected to continue to do so into the coming century. In fact, there is little evidence to support such claims. Climate change is occurring in the East Sahel, but is largely dominated by relatively incoherent fluctuations, not regionally coherent monotonic trends of significant magnitude. Mitigating the risks from the type of extreme climate variability that is evident in the historic rainfall record underscores the imperative to adapt water policies to the local scale. If local communities can be empowered to deal with the type of present-day natural behaviors described here, they should be well-prepared to deal with the pending uncertainties of the future.