Date of Award


Degree Type


Degree Name

Master of Science (MS)


Earth, Atmospheric, and Planetary Sciences

Committee Chair

Ernie Agee

Committee Member 1

Matthew Huber

Committee Member 2

H. Jay Melosh


Earth system models simulate the dynamics of the most complex systems on our planet with some success. Despite the overwhelming sophistication of these models, which include dynamical interactions of ocean, atmosphere, vegetation, ice, and land-surface properties, they fail to include the most important element. People. Humans are also a complex physical-biological system and coupling of human physiology within an Earth Systems Modeling framework is challenging. This thesis presents results that tackle one particular component of human physiological climate interaction--a representation of heat stress on human physiology. Twelve different metrics were implemented and analyzed. These metrics represent a variety of philosophical approaches to characterizing heat stress: thermal comfort, physiological responses, and first principle physics. We implemented these 12 metrics into the Community Land Model (CLM4.5). All of the metrics implemented measure the covariance of near surface atmospheric variables: temperature, pressure, and humidity. Results show that heat stress may be broken into two regimes; arid and non-arid regions (i.e. the rest of the land surface). Additionally, results show that the highest heat stress zones are a robust feature with low variability. Temperatures vary by ±3°C as compared to ±1°C wet bulb temperatures, and is consistent over a vast area of Earth.