Author ORCID Identifier:
Date of Graduation
7-2026
Document Type
Thesis
Degree Name
Master of Science in Agricultural Economics (MS)
Degree Level
Graduate
Department
Crop, Soil & Environmental Sciences
Advisor/Mentor
Nalley, Lawton
Committee Member
Elli, Elivis
Second Committee Member
Steur, Hans De
Third Committee Member
Ala-Kokko, Kristina
Keywords
climate change; extreme heat; food security; maize; south africa
Abstract
As agricultural researchers, policymakers, and producers strive to identify methods to increase global food security, a continually shifting climate poses a persistent challenge. In South Africa, maize (Zea mays) plays a pivotal role in the agricultural economy and food security of the country, but climate change threatens the agricultural productivity of this crop. This study aims to estimate the change in maize yield associated with a 1°C and 2°C temperature increase in South Africa and subsequently frames this change in terms of welfare, rations, and land use. Using a robust dataset of 38,742 dryland maize yield observations from 1986 to 2018 at 92 trial locations across South Africa, we employ a fixed effects modeling approach to estimate the change in yield. Results suggest that a 1°C increase in temperature is associated with a 7.86% decrease in maize yield, and a 2°C increase is associated with a 17.31% decrease. This estimated loss in maize yield results in a $39.7 million (2018 USD) annual decrease in net surplus under the 1°C warming scenario, and an $86.8 million (2018 USD) annual decrease under the 2°C warming scenario. Furthermore, this equates to a reduction in maize rations of 4.6 million people annually and would require 196,205 additional hectares of land to backfill these losses under the 1°C warming scenario. Under the 2°C warming scenario, ration losses increase to 10.1 million people annually, and additional land necessary to keep supply constant is 481,606 hectares. These findings will inform the direction of adaptation and research efforts in South Africa as they continue to increase food security in Southern Africa. The robustness of these results reinforces the necessity for focused policy and research on climate change alleviation in agriculture.
Citation
O'Neill, C. (2026). The Effects of Extreme Heat on South African Maize Yields. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/6321
