# **6 Mechanisms**

In this section we examine the mechanisms that might be driving our results on the negative relationship between heat exposure and test scores.

## **6.1 Do high temperatures in the agricultural season drive the temperature-test score relationship?**

The existing literature provides evidence of heat exposure impacting cognitive performance through the channel of reduced agricultural income in India (Garg et al., 2020). That is, hot days during the agricultural season reduce agricultural yields which reduce parents’ investments in children’s human capital. To test this mechanism in our data, we construct the temperature bins in our main specification separately for the agricultural growing season and non-growing season. The growing season comprises the main growing season, _meher_ , and a shorter minor season called _belg_ , which we pool in our analysis.<sup>17</sup> We identify the typical months for these seasons for each administrative zone in Ethiopia.

We do not find strong evidence to support the hypothesis that this mechanism is at play in our setting. When we compare the impacts of hot days during the growing seasons with those in the non-growing season we find slightly larger effects in the non-growing season (column 1 of Table 3). This is consistent with the effects of high temperature being driven by consequences in the classroom as the non-growing season largely overlaps with the school year.<sup>18</sup> To further explore this, we construct the same set of temperature bins for the school year (covering the academic year) and non-school year separately. The results show that the impact of hot days is more pronounced during the school year compared to the non-school year (column 2 of Table 3). This supports the thesis that the effects of heat on test scores we find are primarily associated with conditions within the classroom environment.

Further, we also tested the differences in results by dividing the data into two subsamples: urban and rural (Table 4). We find that the effect sizes for urban areas are larger than those for rural areas (although they are not statistically different), helping us rule out the hypothesis that hot days during the agricultural season are driving our results.

## **6.2 Do temperature shocks reduce nutrition?**

To answer this question, we utilized data from rounds 2 and 3 of the LSMS-ISA surveys for Ethiopia. We identified household food shocks at the month-year level and aggregated the number of negative food shocks experienced by a household in a calendar year.<sup>19</sup> We

> 17 _Meher_ is the main growing season and lasts from May to September, while the minor growing season, _belg_ , starts in February and ends in April. Around 90% of crop production occurs during the main growing season ( _meher_ ).

> 18See Figure 4 for results for all temperature bins in our data.

> 19The LSMS-ISA surveys collect detailed information on food security status of households. Households were asked if they faced a situation where they did not have enough food to feed all members of the household in the past 12 months, and in which months they faced this food insecurity. We added the number of months where the household faced food insecurity to construct an aggregate measure of the number of food shocks

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