Talitha Neesham-McTiernan
Ph.D. Student
Global Change GIDP
Research Location
Boulder, Colorado
On Site Research Dates
June 15-21, 2025
Title of Research Project:
Protecting Those Who Feed Us: Examining Heat Exposure Mitigation Under Agrivoltaic Systems
Agriculture in the United States depends critically on farmworker labor (1,2), yet these essential workers face heat related risks 20-35 times deadlier than indoor workers (3,4), and projected climate impacts further intensify these dangers (5–8). Despite the crucial role farmworkers play in our $164.7 billion agricultural system9, solutions for protecting them from extreme heat remain limited (10,11).
My PhD dissertation investigates agrivoltaics - the integration of solar panels above crops (12,13) - as a promising approach to heat protection for farmworkers. Research has shown these systems can reduce plant thermal stress, improve crop yields, and conserve water by creating a shaded growing environment (14–20). However, their potential to similarly mitigate farmworker heat stress remains unexplored. Understanding this potential is crucial for developing sustainable solutions that protect both agricultural productivity and farmworker wellbeing.
My research addresses four key questions:
1. To what extent do agrivoltaic systems protect farmworkers from heat exposure?
2. How will agrivoltaic heat exposure mitigation change under future climate conditions?
3. How do farmworkers experience heat exposure in agrivoltaic versus traditional open field settings?
4. How do farmworkers' lived experiences of heat exposure in agrivoltaic settings align with quantitative measurements?
As a central component of my dissertation, I have already analyzed four years of microclimate data from adjacent traditional open field (control) and agrivoltaic research sites in Arizona and Colorado. Using this data, I have calculated wet bulb globe temperature (WBGT) values (21), a comprehensive heat stress metric that captures key environmental factors affecting farmworkers' heat stress, including solar radiation, humidity, air temperature, and wind speed (22,23). By integrating these factors, WBGT provides a more nuanced assessment of thermal comfort than temperature alone (24). From these calculated WBGT values I have developed a predictive model of heat stress conditions in agrivoltaic systems across the southwest under current and future climate conditions. Validating this model through direct WBGT measurements is now the critical next step in my research. Without these validation measurements, the predictive power and broader applicability of my model would remain untested, significantly limiting its scientific value and potential impact on farmworker protection policies.
Beyond physical measurements, understanding heat protection requires investigating how farmworkers themselves experience these environments. Through interviews with farmworkers (n=15), I will explore their thermal comfort, adaptation strategies, and overall working experiences in both agrivoltaic and traditional open field settings. These interviews provide crucial insights that cannot be captured through instrumentation alone and are essential for understanding the human dimension of heat exposure and protection under agrivoltaic systems.
I have secured funding from the Western Center for Agricultural Health and Safety to conduct both the validation measurements and interviews at our Arizona research site. However, completing a robust, geographically diverse study requires parallel data collection at our Colorado site. The Gruener Research Travel Award would support a week-long research trip to our Boulder, Colorado agrivoltaic research site during June 2025.
Travel to the Colorado site during peak summer heat in June is critical for three key reasons. First, geographic diversity is essential for model validation. While our Arizona sites represent extreme heat conditions typical of the lower desert Southwest, the Colorado site offers different temperature ranges, humidity levels, and solar radiation patterns characteristic of higher elevation environments. This climatic gradient is necessary to validate my statistical model's applicability across diverse agricultural landscapes in the Southwest. Second, summer timing coincides with maximum heat risk to farmworkers, making it the optimal period to capture both quantitative measurements and farmworker experiences of heat stress. Missing this summer window would delay my dissertation completion by a full year. Third, my physical presence at the Colorado site enables methodological consistency between the two research locations. The interviews and direct measurements must occur simultaneously to allow farmworkers to provide immediate feedback about their thermal comfort while I record the corresponding environmental conditions.
This research trip would catalyze my career by enabling me to publish the first comprehensive assessment of agrivoltaics as a heat mitigation strategy for agricultural workers. The interdisciplinary nature of this work aligns perfectly with my career goal of developing practical climate adaptation strategies that protect vulnerable populations while advancing sustainable agriculture. Additionally, completing this geographically diverse study will strengthen my profile for future research opportunities and funding in climate-resilient agricultural systems. This innovative approach bridges multiple disciplines - agricultural science, renewable energy, occupational health, and climate adaptation - positioning me to make unique contributions at this critical intersection.
By supporting this research trip, the Gruener Research Travel Award would enable the completion of two essential chapters of my PhD dissertation while advancing our understanding of agrivoltaics as a heat mitigation strategy. This work has direct implications for farmworker safety throughout the Southwest, potentially improving health outcomes for thousands of vulnerable workers through the identification of effective heat protection measures.
References
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