A New, Zero-Iteration Analytic Implementation of Wet-Bulb Globe Temperature: Development, Validation, and Comparison...

Area of Science:

• Environmental Science
• Occupational Health
• Climate Science

Background:

• Wet-bulb globe temperature (WBGT) is crucial for workplace heat stress regulation.
• Calculating WBGT typically requires iterative methods, limiting its widespread application.
• Existing simplified WBGT approximations often introduce significant bias.

Purpose of the Study:

• To develop a zero-iteration analytic approximation for WBGT.
• To maintain the accuracy and physical basis of the original iterative model.
• To enhance the practical application of WBGT in heat stress assessment.

Main Methods:

• Analysis of self-nonlinearities within Liljegren's WBGT model.
• Development of a novel analytic approximation requiring no iteration.
• Validation against the full iterative WBGT model across diverse global conditions.

Main Results:

• The new approximation shows minimal deviation (<1°C in 99% of cases) from the full model over 93% of global land area.
• Annual mean and high percentiles of WBGT are accurately represented globally.
• The developed approximation is demonstrably more accurate than other common WBGT approximations.

Conclusions:

• A highly accurate, non-iterative analytic approximation for WBGT has been successfully developed.
• This method overcomes limitations of previous approximations, offering improved accuracy and physical interpretability.
• The findings provide a foundation for better understanding and managing heat stress through improved WBGT assessment.