This paper estimates ENSO’s association with child nutrition at a global scale by combining variation in ENSO intensity from 1986–2018 with children’s height and weight from 186 surveys conducted in 51 teleconnected countries, containing 48% of the world’s under-5 population. Warmer El Niño conditions predict worse child undernutrition in most of the developing world, but better outcomes in areas where precipitation is positively affected by warmer ENSO. ENSO’s effects on child weight loss are detectable years later as decreases in height. This relationship is similar at both global and regional scales and has not weakened over the last four decades. Results imply that almost 6 million additional children were underweight during the 2015 El Niño compared to a counterfactual of neutral ENSO conditions in 2015.

Jesse K. Anttila-Hughes, Amir S. Jina, Gordon C. McCord