Comparison of human perceived temperature between in-situ and reanalysis datasets in Denver, Colorado
Urban heat stress can be caused by transitioning from natural, non-urbanized environments to dense urban environments, as this increases the number of buildings, roads, and other infrastructure. A commonly used metric to study heat stress is Wet Bulb Globe Temperature (WBGT), which is a “feels like†temperature that incorporates wind speed, relative humidity, cloud cover, and temperature. Over a three-month field campaign in Denver, Colorado, in the summer of 2025, Kestrel 5400 heat sensors were used to measure WBGT over grass, native grass, wood mulch, gravel, and artificial grass in five parks. To better understand the individual effects of landscapes, a regional WBGT must be calculated from ERA5 climate and weather data. This study uses wind speed, dew point temperature, air temperature, and net solar radiation to determine a regional WBGT value for each park examined. This WBGT can then be compared with the value observed in the field, allowing comparison of values across different parks and days. This work is important for assessing the environmental effects of waterwise landscapes that may be implemented in arid or semi-arid cities to reduce municipal outdoor water use.