Climate Change, Crop Yields, and Undernutrition: Development of a Model to Quantify the Impact of Climate Scenarios on Child Undernutrition

Abstract

Background: Global climate change is anticipated to reduce future cereal yields and threaten food security, thus potentially increasing the risk of undernutrition. The causation of undernutrition is complex, and there is a need to develop models that better quantify the potential impacts of climate change on population health.Objectives: We developed a model for estimating future undernutrition that accounts for food and nonfood (socioeconomic) causes and can be linked to available regional scenario data. We estimated child stunting attributable to climate change in five regions in South Asia and sub-Saharan Africa (SSA) in 2050.Methods: We used current national food availability and undernutrition data to parameterize and validate a global model, using a process-driven approach based on estimations of the physiological relationship between a lack of food and stunting. We estimated stunting in 2050 using published modeled national calorie availability under two climate scenarios and a reference scenario (no climate change).Results: We estimated that climate change will lead to a relative increase in moderate stunting of 1–29% in 2050 compared with a future without climate change. Climate change will have a greater impact on rates of severe stunting, which we estimated will increase by 23% (central SSA) to 62% (South Asia).Conclusions: Climate change is likely to impair future efforts to reduce child malnutrition in South Asia and SSA, even when economic growth is taken into account. Our model suggests that to reduce and prevent future undernutrition, it is necessary to both increase food access and improve socioeconomic conditions, as well as reduce greenhouse gas emissions.

Systematic review of current efforts to quantify the impacts of climate change on undernutrition

“…However, a majority of the previous studies make only partial assessments. We found only two models that covered agroclimatic analysis to evaluate effects on childhood malnutrition (9,26) and one review assessing the impacts of climate change on pregnancy outcomes (27). Earlier reviews have investigated the impact of agricultural interventions or food production and agricultural strategies for improving outcomes in children's nutrition and health (28)(29)(30), the impact of climate change on disability-adjusted life years (31), the impacts of temperature on children's health (32), the health effects of drought (33), and the effects of climate change on crops yields (34).…”

“…In Africa more than 36% of the children under age 5 y are stunted (7). Lloyd et al predict relative increases in severe stunting of 31-55% in West sub-Saharan Africa and 61% in South Asia, making it an impending epidemic and therefore a critical research priority (8,9).…”

Food Security in a Changing Climate: A Plea for Ambitious Action and Inclusive Development

“…According to Springmann et al (2016), the reduced availability of fruits and vegetables will contribute to an additional 534,000 deaths per year in 2050, due to subsequent deficiencies in vitamins. Lloyd et al (2011) also shows the increase in carbon dioxide air concentration will reduce the iron, zinc and protein content in grains. In addition, warmer or wetter conditions in certain areas will increase the concentration of aflatoxins in stored staple foods, which represents an additional health risk.…”

“…Estimates of its impact show that severe stunting in children could increase by 23 percent in central subSaharan Africa and 62 percent in South Asia by 2050 compared to a future without climate change (Lloyd et al 2011). Indeed climate change impacts every pillar of food security (availability, access, quality and stability) along with the components of nutrition security.…”

Impact of Climate Change, Weather Extremes, and Price Risk on Global Food Supply

“…The other big challenge for food insecurity stems from changes in climate and weather extremes. Under a business as usual scenario, climate change may increase child stunting by about a quarter in Sub-Saharan Africa and by nearly two-thirds in South Asia by 2050 (Lloyd et al 2011). Climate change has manifested itself with increasing global mean surface temperature, higher rates of temperature and precipitation extremes, and more frequent droughts in some regions (IPCC 2007).…”