Characterizing the contribution of high temperatures to child undernourishment in Sub-Saharan Africa

Abstract

Despite improvements to global economic conditions, child undernourishment has increased in recent years, with approximately 7.5% of children suffering from wasting. Climate change is expected to worsen food insecurity and increase potential threats to nutrition, particularly in low-income and lower-middle income countries where the majority of undernourished children live. We combine anthropometric data for 192,000 children from 30 countries in Sub-Saharan Africa with historical climate data to directly estimate the effect of temperature on key malnutrition outcomes. We first document a strong negative relationship between child weight and average temperature across regions. We then exploit variation in weather conditions to statistically identify the effects of increased temperatures over multiple time scales on child nutrition. Increased temperatures in the month of survey, year leading up to survey and child lifetime lead to meaningful declines in acute measures of child nutrition. We find that the lifetime-scale effects explain most of the region-level negative relationship between weight and temperature, indicating that high temperatures may be a constraint on child nutrition. We use CMIP5 local temperature projections to project the impact of future warming, and find substantial increases in malnutrition depending on location: western Africa would see a 37% increase in the prevalence of wasting by 2100, and central and eastern Africa 25%.