Climate Change Threat to Health

Discussions about the effects of climate change and climate change adaptation often center on changes in crop yields and subsequent changes in food security and incomes . In addition to these immediate impacts, however, climate change can have important secondary effects on a range of other development indicators. These secondary effects have not received much attention, but a new article in Ecological Indicators tries to fill that gap by examining to what extent climate change impacts food consumption, nutrition, health expenditures, education, recreation, and human development potential among smallholder farmers in Zimbabwe, Cameroon, South Africa, and Ethiopia by 2050.

The study finds that steady shifts in climate patterns, and their associated income reductions, have a moderate to high impact on these populations. Namely, smallholders face increased vulnerability to diseases and nutritional disorders, a significant lack of educational opportunities, and an ultimate reduction in the potential for human and societal development.

According to the paper, there are several uncertainties underlying estimations of climatic changes, income changes, and their secondary consequences, including uncertainties regarding estimates of regression relations, the climate model used to estimate temperature and rainfall, and expected trajectories of greenhouse gas emissions.  The authors use a weighting scheme to take these uncertainties into account and to provide a set of estimates that policymakers can use when setting climate change adaptation and development policies.

In terms of food consumption, the study finds that climate change and climate change-driven income reductions will lead to sizeable impacts on overall food consumption, although the extent of those impacts vary throughout the region. Consumption of cereals will be less affected than other food categories, largely because of comparatively lower elasticity levels of cereal consumption in the study countries. Among the four countries studied, Zimbabwe may face the largest decline in cereal consumption. Any decline in cereal consumption in these countries could lead to an important decline in overall caloric consumption, however, because cereals make up a significant portion of rural diets. Since caloric consumption is already lower than recommended levels for many farming households in these countries, this could have serious impacts on hunger, nutrition, and human health.

Meat consumption is also already at low levels in the study countries, and the predicted fall  in meat consumption in Zimbabwe, South Africa, and Cameroon due to climate change-driven income reductions could increase the incidence of anemia. Finally, climate change and subsequent reduced incomes will also reduce consumption of oils, fats, and fruits; this could lead to important micronutrient deficiencies, increasing chronic malnutrition, child stunting, and susceptibility to diseases like HIV. The authors also suggest that these effects could be proportionally higher for girls, women, and the elderly, as these populations often forego their own consumption to ensure food for male household members.

The study also finds that climate change and subsequent reduced agricultural incomes may lead to an disproportionate reduction in money spent on medical and health services, compared to other study categories, due to the high elasticity of consumption of these services. The use of medical care is already quite low in the study countries, according to the authors, and a further reduction could make smallholders even more vulnerable to diseases like malaria and tuberculosis. These illnesses often cause further losses in productivity as sick farm laborers are unable to work, leading to a vicious cycle. Women, again, are expected to be disproportionally affected by these reductions in medical expenditures, particularly during pregnancy, delivery, and lactation.

Children’s education is also likely to suffer as a result of climate change and reduced farm incomes, with secondary and tertiary school enrollment falling significantly as families allocate declining financial resources to more immediate needs like food and housing. Girls will be disproportionately affected, as many households in the study countries disproportionally support the education of male children over female children. For example, the gender parity index for upper secondary level education was 0.61 in Cameroon, 0.58 in Ethiopia, 0.86 in Zimbabwe in 2005, according to UNESCO.

Overall, these reductions in food consumption, medical expenditures, and education will have a significant negative impact on human development in the region. For example, life expectancy may fall as a result of increased malnutrition and susceptibility to disease combined with reduced ability to pay for healthcare.

Understanding these secondary effects of climate change can help policymakers establish appropriate safety net and adaptation programs to protect rural populations, particularly smallholders and women. First, the authors recommend ways to sustain rural income levels, such as providing increased irrigation services, encouraging the use of heat-tolerant crop varieties, increasing funding and support for agricultural research and development and extension services, and generating off-farm employment opportunities.

In addition, social safety net programs, such as supplementary feeding programs or Ethiopia’s Productive Safety Net Programme (PSNP), should be established or expanded to help ensure food and/or cash income for food-insecure households. In addition, policymakers should focus on reducing educational costs or providing financial assistance for students from areas negatively affected by climate change, and low-cost rural health centers and health insurance schemes should be established or expanded.

By: Sara Gustafson, IFPRI