# **1 Introduction**

There is now abundant evidence from rich counties that heat reduces the formation and utilization of human capital in academic settings.<sup>1</sup> This evidence demonstrates that heat has acute negative impacts, reducing performance on exams on hot days, and longer-term negative effects, reducing the amount that students learn during hotter years. However, how these impacts translate to developing country contexts remains under-investigated. This is especially crucial in low income countries where introducing adaptation measures may be challenging due to generally lower average incomes. The lack of evidence for SubSaharan Africa is particularly acute. In this study, we examine the relationship between high temperatures and learning outcomes in Ethiopia in a high stakes exam setting.

While there exists a large literature documenting the negative impacts of extreme ambient temperatures on human capital formation, there remain gaps. Park et al. (2021) find that heat exposure is associated with reduced rate of skill formation or cumulative learning in both the U.S. and internationally. But their sample includes almost no Sub-Saharan African countries. Graff Zivin et al. (2018) find that short-run changes in temperatures in the US beyond 26 degrees Celsius are associated with lower cognitive performance on math, but not on reading. Cho (2017) and Garg, Jagnani, and Taraz (2020) find similar results in the contexts of the Republic of Korea and India, respectively. Park et al. (2020) use data on students who retook the Practice Scholastic Assessment Test (PSAT) in the US to find that high temperatures during school days inhibit learning and thereby reduce test scores. Further, their findings suggest that air conditioning in classrooms can mitigate the adverse effects of high temperatures.

In the developing country context, there is an evidence gap for high-stakes academic settings among older students. Garg et al. (2020) identify that hot days during the agricultural growing season are associated with both lower agricultural yields as well as lower test scores for younger students in rural India. They provide suggestive evidence of the introduction of a workfare program weakening the effects of high temperatures on test scores. Zhang, Chen, and Zhang (in press) find that the prevalence of high temperatures at the time of a low stakes cognitive test evaluated during household surveys in China is associated with reduced cognitive performance, especially for older and less educated respondents. In high stakes settings, evidence from China suggests that that high temperatures during the day of the exam are negatively associated with test performance (Graff Zivin, Song, Tang, & Zhang, 2020).

Existing studies either provide evidence on the impacts of heat on cognitive performance in high-stakes settings in rich countries or in lower-stakes settings in middle income countries.<sup>2</sup> Our paper fills a gap in the literature examining the direct impact of heat

> 1See, for example, Graff Zivin, Hsiang, and Neidell (2018); Park, Behrer, and Goodman (2021); Park, Goodman, Hurwitz, and Smith (2020). For a broad overview of this literature see Park and Heal (2016).

> 2On the separate, but related, question of school attendance, Randell and Gray (2019) study 29 tropical countries, which include 11 African countries (excluding Ethiopia), and find negative impacts of prenatal exposure to higher-than-average temperatures on years of schooling completed. Furthermore, they find that these effects are pervasive across all income groups; especially in the case of West and Central Africa. They

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