East African food security as influenced by future climate change and land use change at local to regional scales

Abstract

Climate change impacts food production systems, particularly in locations with large, vulnerable populations. Elevated greenhouse gases (GHG), as well as land cover/land use change (LCLUC), can influence regional climate dynamics. Biophysical factors such as topography, soil type, and seasonal rainfall can strongly affect crop yields. We used a regional climate model derived from the Regional Atmospheric Modeling System (RAMS) to compare the effects of projected future GHG and future LCLUC on spatial variability of crop yields in East Africa. 824 Climatic Change (2012) 110:823-844 Crop yields were estimated with a process-based simulation model. The results suggest that: (1) GHG-influenced and LCLUC-influenced yield changes are highly heterogeneous across this region; (2) LCLUC effects are significant drivers of yield change; and (3) high spatial variability in yield is indicated for several key agricultural sub-regions of East Africa. Food production risk when considered at the household scale is largely dependent on the occurrence of extremes, so mean yield in some cases may be an incomplete predictor of risk. The broad range of projected crop yields reflects enormous variability in key parameters that underlie regional food security; hence, donor institutions' strategies and investments might benefit from considering the spatial distribution around mean impacts for a given region. Ultimately, global assessments of food security risk would benefit from including regional and local assessments of climate impacts on food production. This may be less of a consideration in other regions. This study supports the concept that LCLUC is a first-order factor in assessing food production risk.

Impacts of Climate Variability and Change on Rainfed Sorghum and Maize: Implications for Food Security Policy in Tanzania

“…The higher range of predictions for maize across GCMs, reflects the uncertainty of climate prediction impacts using GCMs. Similar results were obtained by Moore et al (2012) who reported between 20% and 30 % decrease in maize yields towards mid-century in Morogoro. They attributed the uncertainty to combined effects of greenhouse gas emissions and land cover land use change (LCLUC).…”

“…While results from the current study agree and/or disagree with some large scale studies, their strength emanate from the consideration of local crop specific varieties and management practices and the consideration of relevant weather information. In the central zone, the study showed that the magnitude of maize yield decline at least to mid-century is not likely to exceed 25%, results which are in agreement with Moore et al (2012). In contrast, Mwandosya et al (1998) projected a decline in maize yields of between 80 and 90% towards the end of the century.…”

Assessment of the Impacts of Climate Change on Maize Production in the Southern and Western Highlands Sub-agro Ecological Zones of Tanzania

“…These increases in temperatures influence the decline in maize yields in the southern southwestern sub-ecological zones of Tanzania. The study by Moore et al (2011) suggested that increase in temperatures reduce the length of growing season that can either decrease yields (if currently warm) or increase yields (if currently cool).…”

Climate Change Adaptation Strategies in Sub-Saharan Africa: Foundations for the Future

“…In [24] a regional climate model to compare the effects of projected greenhouse gases concentration and land use land cover change on spatial variation of crop yields in East Africa has been used. In addition, the extent to which projected rainfall and temperature trends are, or are not, yet becoming evident in daily and seasonal weather observations have also been assessed [13,15,14].…”