Selection of Appropriate Thermal Indices for Applications in Human Biometeorological Studies

Abstract

Application of thermal indices has become very popular over the last three decades. It is mostly aimed at urban areas and is also used in weather forecasting, especially for heat health warning systems. Recent studies also show the relevance of thermal indices and their justification for thermal perception. Only twelve out of 165 indices of human thermal perception are classified to be principally suitable for the human biometeorological evaluation of climate for urban and regional planning: this requests that the thermal indices provide an equivalent air temperature of an isothermal reference with minor wind velocity. Furthermore, thermal indices must be traceable to complete human energy budget models consisting of both a controlled passive system (heat transfer between body and environment) and a controlling active system, which provides a positive feedback on temperature deviations from neutral conditions of the body core and skin as it is the case in nature. Seven out of the twelve indices are fully suitable, of which three overlap with the others. Accordingly, the following four indices were selected as appropriate: Universal Thermal Climate Index (UTCI), Perceived Temperature (PTJ), Physiologically Equivalent Temperature (PET), and rational Standard Effective Temperature (SET*).

Investigating the Behaviour of Human Thermal Indices under Divergent Atmospheric Conditions: A Sensitivity Analysis Approach

“…In addition, and while critical studies pertaining to climatic indices were disseminated before the turn of the century [1][2][3][4][5][6][7][8][9][10][11][12][13], since the ingress into the twenty-first century (and arguably further instigated by the arrival of the climate change adaptation agenda), the importance and development of climatic indices have increased. In accordance with the rational presented by Potchter et al [14], the associated research complexity intrinsic to climatic models can be seen under two prisms, the: (i) overall review, cataloguing, structuring, and fragmentation of index typologies based upon their equational suitability and methodical pertinence [15][16][17][18][19][20]; and, (ii) the pursuit and testing of the most suitable index to estimate thermal comfort thresholds within a specific outdoor and climatic setting [21][22][23][24][25][26][27][28]. Both of these perspectives indicate the significance and opportunities regarding the correct approach to human thermal comfort thresholds within urban environments.…”

“…It is worth noting that although the new mPET index was not included in the comprehensive list of thermal indices; based upon its close intrinsic revision of the original MEMI model [57], it was upheld within the Energy Balance Model index typology ( Figure 1). As indicated by Staiger et al [20], such a revision can be attributed to the improvement of the heat transfer simulation resultant of a more efficient bio-heat equation, as presented by Pennes [1]. Out of the one hundred and sixty-two thermal indices examined by de Freitas and Grigorieva [16], the six applied in this study fall into the respective categories of 'C' and 'G', representing an Algebraic/Statistical Model and an Energy Balance Model, respectively.…”

“…It is worth noting that although the new mPET index was not included in the comprehensive list of thermal indices; based upon its close intrinsic revision of the original MEMI model [57], it was upheld within the Energy Balance Model index typology. As indicated by Staiger et al [20], such a revision can be attributed to the improvement of the heat transfer simulation resultant of a more efficient bio-heat equation, as presented by Pennes [1].…”

“…Alternatively, the 'G' category accommodates indices which are constructed upon more intricate and multifarious human thermal regulation models as discussed in numerous studies, including other review articles [14,17,18,20,34,81], and research articles [21,25,84,85]. In addition to these disclosed studies, there has also been a promising amount of interdisciplinary investigations which have utilized the indices to bridge urban biometeorology with other disciplines that can directly scrutinize and improve the thermal responsiveness of the urban public realm.…”

A New Approach for Generating Human Biometeorological Information Based on Gridded High-Resolution Data (Basic Data of Test-Reference-Years)

“…However, slightly cold conditions can be used as a positive stimulation effect for climatotherapy [1]. Several approaches exist to capture the complexity of the human body´s heat exchange with the environment, generating an assessment index of thermal perception [4]. Examples of such thermal indices are the Perceived Temperature (PT) from the German Meteorological Service (Deutscher Wetterdienst, DWD) [5][6][7], the Physiologically Equivalent Temperature (PET) [8][9][10][11], and the Universal Thermal Climate Index (UTCI) [12].…”