Climate patterns reveal when food price spikes worsen hunger risks
Climate Variability Modulates the Impact of Price Spikes on Food Insecurity
Machine Learning
Summary
Food prices can suddenly rise and make it harder for people to get enough to eat, but not everywhere in the same way. The authors found that climate patterns, especially the El Niño cycle, affect how much these price jumps lead to food problems in different parts of sub-Saharan Africa. In places where El Niño harms plant growth, food price spikes cause a bigger increase in people facing severe hunger. This means knowing about climate patterns ahead of time could help target aid to places most likely to suffer when prices spike.
What this means in practice
- •For humanitarian aid planners: Use El Niño climate data combined with food price increases to target emergency food aid more precisely in vulnerable African regions months in advance.
- •For agricultural risk analysts: Incorporate vegetation response to El Niño into models assessing crop failure risks linked to market disruptions to improve food security forecasts.
Authors
Jordi Cerdà-Bautista, Vasileios Sitokonstantinou, Homer Durand, Gherardo Varando, Michele Ronco, Gustau Camps-Valls
Abstract
Climate variability influences whether a market disruption escalates into a food crisis, yet broad climate patterns like El Niño, tracked months before they alter hydro-climatic conditions, are still not incorporated as an early-warning component in food-security responses. We address this gap by introducing sensitivity regimes, a stratification of regions by the direction and strength of their vegetation response to the El Niño Southern Oscillation, and using them to estimate how food price spikes affect acute food insecurity across sub-Saharan Africa. Integrating remote sensing, socioeconomic data, and causal machine learning, we find that in regions where ENSO systematically suppresses vegetation, a price spike raises the share of the population at acute risk by 5.4 percentage points in the following month. In regions where vegetation is unaffected by or positively linked to ENSO, the estimated effect is smaller (around 2 percentage points) and statistically insignificant. These results demonstrate that climate context is critical for understanding food security vulnerabilities. Sensitivity regimes can be combined with operational price-spike triggers to stage anticipatory action: the ENSO state flags vulnerable regions months ahead, and a pre-positioned response in those regions to a price spike would avert the largest jump in acute food insecurity.