Analysis of the Universal Thermal Climate Index during heat waves in Serbia

Abstract

Abstract. The objective of this paper is to assess the bioclimatic conditions in Serbia during summer in order to identify biothermal heat hazard. Special emphasis is placed on the bioclimatic index UTCI (Universal Thermal Climate Index), whose purpose is to evaluate the degree of thermal stress that the human body is exposed to. For this research, mean daily and hourly (07:00 and 14:00 CET) meteorological data from three weather stations (Zlatibor, Novi Sad and Niš) have been collected for the period from 1998 to 2017. In order to identify patterns of biothermal heat stress conditions, the thresholds of the daily UTCI (UTCI ≥38 ∘C, referred to as very strong heat stress, VSHS) at 14:00 CET are compared with the thresholds of daily maximum air temperature (tmax⁡≥35 ∘C, referred to as hot days, HDs), which are further termed as heat wave events (HWEs). The findings show that the UTCI heat stress category “very strong heat stress“ at 14:00 CET indicates heat waves. The most extreme heat wave events occurred in 2007, 2012, 2015 and 2017. Moreover, three HWEs at Niš that occurred in July 2007 lasted 3, 10 and 4 d. HWEs and very strong heat stress events (VSHSEs) recorded in July 2007 (lasted 10 d each), 2012 (lasted 9 and 12 d) and 2015 (lasted 7 and 10 d) were of the longest duration and are considered to be the indicators of biothermal heat hazard. The daily UTCI14 h heat stress becomes more extreme in terms of severity and heat wave duration up to very strong heat stress.

Bioclimatic Conditions of June 2019 in Poland on a Multi-Year Background (1966–2019)

“…Krzyżewska et al [46] evidenced that from the beginning of the 21st century, such changes primarily concerned the central, upland, and south-eastern regions, emphasising their potential negative effect on the intensity of tourist traffic in these areas. A similar direction of changes in human-biometeorological conditions was also determined in other regions of Europe [29,47,48].…”

“…[22][23][24][25]. This type of indices has been frequently applied in the general assessment of human-biometeorological conditions or assessment of extreme situations at various spatial scales and in different climatic zones [26][27][28][29][30][31]. In recent years, studies from Poland have involved the analysis of human-biometeorological conditions occurring during selected heat waves [32,33].…”

Temporal Analysis of Urban-Suburban PET, mPET and UTCI Indices in Belgrade (Serbia)

“…The results show a significant increase in values of the UTCI, PET and mPET over the last 46 years. A series of peaks can be observed in the years 1990, 1998, 2000, 2007, 2012, 2015 and 2017 that have been marked as extremely warm according to previous investigation [11][12][13][14][16][17][18]21,22,25]. In addition, there is a growing trend of each index in both stations, i.e., a series of peaks with successively higher values during the investigated period (1976-2018).…”

“…Studies of the Belgrade climate conducted to date have mostly been based on individual meteorological parameters used for the analysis of the urban climate characteristics. These mainly referred to the characteristics of urban heat islands defined by average air temperatures or extreme air temperatures [1][2][3][4][5][6][7], air humidity characteristics in urban and suburban areas [8] and heatwave analysis [9][10][11][12][13][14][15][16][17][18][19]. Regarding the assessment of bioclimatic indices, simple index Steadman apparent temperature [20] was analyzed by Stanojevic et al [21] and Humidex by Lukic [22], while in terms of the heat budget indices, an analysis of heat load (HL) on man derived from Menex model [23,24] and UTCI only for extreme months, January and July [25], were analyzed for Belgrade no more than a ten-year data series.…”

The assessment of human bioclimate of Vranje health resort (Serbia) based on Universal Thermal Climate Index (UTCI) with the focus on extreme biothermal conditions

“…Based on the assessment of UTCI and the interpretation of human bioclimatic conditions in Vranje health resort region, during the period 2000-2017, the most extreme years can be distinguished by several characteristics: • Extreme years in the summer season (2007,2015) • Extreme years for both summer and winter seasons (2000,2003,2012,2017) • Extreme years in the winter season (2001,2002,2004) • Unusually extreme month (September 2015) • Extreme days with increasing heat stress excluding summer (dUTCI > 0) (November 2008(November -2012(November , 2017 However, in recent research, the UTCI has been increasingly helping as a determinant of extreme weather condition (Theoharatos et al, 2010;Urban & Kyselý, 2014;Di Napoli et al, 2018, 2019Pecelj et al, 2020). Furthermore, complete hourly weather data are missing in order to be able to analyse UTCI values in more detail which might be applied for health purposes considering the vicinity of health spa resort Vranjska Banja.…”