UNIVERSITY PARK, Pa. — Food insecurity is a growing problem in some parts of the world, especially as climate change affects weather conditions around the world. New research led by Penn State found that a lack of rainfall is associated with the highest risk of food insecurity in Tanzania.
Specifically, the researchers found that moving from a year with normal rainfall to a particularly dry year was associated with a 13 percentage point increase in the risk of food insecurity for Tanzanian households, likely due to a reduced impact of rainfall on maize production. .
Heather Randell, assistant professor of rural sociology and demography in the College of Agricultural Sciences, said the findings could have important policy implications focused on helping agricultural households become more resilient against drought conditions.
“Climate change will continue to alter precipitation patterns, so it is essential to find ways to help at-risk communities protect against food insecurity,” said Randell. “Possible interventions could include providing drought-tolerant maize, increasing access to agricultural extension services, increasing agricultural index insurance, increasing uptake of soil and water conservation practices, and providing systems-based cash transfers drought early warning.”
Randell said the findings – recently published in the journal Food Policy – could also be relevant to other low- and middle-income countries, particularly those that rely heavily on maize production.
According to the researchers, food insecurity – the inability to acquire adequate, nutritious, safe and affordable food – affected around 2 billion people, or 26% of the global population, in 2019. This is particularly true in Africa Sub-Saharan, where the number of cases of moderate or severe food insecurity increased from 50% in 2014 to 57% in 2019.
Previous research has found that food insecurity can affect physical and mental health, which in turn can affect household labor productivity, child growth and development, and poverty reduction.
But although the Intergovernmental Panel on Climate Change predicts that climate change will increasingly threaten food and nutrition security — especially in poorer parts of the world that depend on agricultural production — the researchers said that very little research has been done to examine the effects of rainfall and temperature on how and whether households experience food insecurity.
“Most previous studies have focused on other related outcomes, such as children’s nutritional status or food expenditure,” says Randell. “But these do not give a comprehensive picture of how climatic conditions affect the quality, quantity and variety of food that households can obtain.”
For the current study, the research team wanted to examine how varying weather conditions were associated with food security in Tanzania, a country with a high prevalence of food insecurity that is also highly dependent on rainfall to grow its maize crops.
The researchers linked nationally representative, longitudinal household survey data from more than 3,200 households across Tanzania with high-resolution data on rainfall and temperature during the most recent growing season.
The survey data – collected by Tanzania’s National Bureau of Statistics with support from the World Bank’s Living Standards Measurement Study – Integrated Survey on Agriculture – included information on the quantity and quality of foods consumed in the household and how households responding to food shortages. This data was then used to determine whether a household was food insecure or not.
“It is likely that the relationship between low rainfall and food insecurity is primarily driven by weather effects on maize production,” said Randell. “Maize thrives in warm conditions with plenty of rain, as the crop is sensitive to drought and to frost damage and extreme heat.”
In addition, the researchers found that households with fewer members of working age were most at risk of food insecurity after experiencing low rainfall. Randell said this is likely because, during drought conditions, households with only one or two working-age members have fewer opportunities to earn additional income compared to those with three or more working-age members.
The researchers said the findings will continue to be important as the weather changes within the country. Climate projections for Tanzania predict generally warmer temperatures but more variable rainfall across the country, with more annual rainfall predicted in the northern and north-eastern parts of the country but less rainfall predicted in the south.
Clark Gray, University of North Carolina, and Elizabeth H. Shayo, National Institute for Medical Research, also participated in this work.
The Eunice Kennedy Shriver National Institute of Child Health and Human Development helped support this research.