Outdoor Universal Thermal Comfort Index Climatology for Alaska

Abstract

Data from 456 surface meteorological sites in Alaska, eastern Russia and northwest Canada for 1979-2017 were used to model hourly universal thermal comfort indices (UTCIs) under consideration of Alaska-appropriate clothing. The results served to determine a high-resolution climatology of thermal comfort levels for Alaska at various temporal and spatial scales as well as the frequency of thermal stress levels. On 1979-2017 average, various degrees of cold stress occurred with highest percentage on the Alaska West Coast and along the Arctic Ocean. In the continental and Inside Passage region, no thermal stress had the highest percentage of occurrence. In Interior Alaska, both strong heat and extreme cold stress occurred occasionally. At most sites and in all Alaska Köppen-Geiger bio-climate regions, the absolute range between monthly means of daily minimum and maximum UTCIs was larger than that of monthly means of daily minimum and maximum air temperatures. Major contributors to thermal discomfort (shortwave radiation, air temperature, moisture, wind speed) varied among bio-climate regions and in the diurnal and annual courses.

Summer UTCI variability in Poland in the twenty-first century

“…It was proven that UTCI better reflects temporal thermal variability, especially with hot conditions, than indices like Heat Index, Wet-bulb globe temperature, humidex and slightly better from apparent temperature and effective temperature, and it corresponds the best with other indexes based on human health balance models, like Physiological Equivalent Temperature, perceived temperature and standard effective temperature (Blazejczyk et al 2012 ; Zare et al 2018 ). Also, because UTCI is very sensitive to changes in ambient stimuli (like human body), it better represents different climate, weather and location conditions than other indices, which are reasonable only under specific meteorological situations (Blazejczyk et al 2012 ; Mölders 2019 ). Also, evaluated clothing model is implemented in UTCI which considers human behaviour (Havenith et al 2012 ).…”

Spatiotemporal characteristics of human thermal comfort across southern Africa: An analysis of the Universal Thermal Climate Index for 1971–2021

“…In 2009, following 10 years of development, the Universal Thermal Climate Index (UTCI) was presented to the scientific community to address these shortfalls (Błażejczyk, 2021). In the 13 years since its finalization, the UTCI has been applied extensively across the global north (Di Napoli et al ., 2018; Mölders, 2019; Varentsov et al ., 2020; Antonescu et al ., 2021; Krüger, 2021), yet little work has been undertaken to use this index to consider thermal stress in African or southern African contexts (Di Napoli et al ., 2022; Shukla et al ., 2022). Since anthropogenically induced climate change has heightened the probability of extreme temperature events (ETEs), and the incidence of thermal stress (Masson‐Delmotte et al ., 2021), it is important to assess changes in thermal comfort at a regional scale over recent decades, using a comprehensive multifactoral index such as the UTCI.…”

Evaluation and Prediction Model for Ice–Snow Tourism Suitability under Climate Warming

“…At present, the most common models for climate comfort evaluations can be divided into two major categories: empirical models and mechanistic models [4,5]. The mechanistic models are based on the human heat balance equation, and they have become the mainstream direction of "theoretical research" on climate comfort models in the past 50 years [6,7]. However, the calculation of the human thermal balance equation involves the estimation of many variables, such as the clothing surface average temperature, the skin average temperature, and the human body's sweating rate [8].…”