scholarly journals Verification of Heat Stress Thresholds for a Health-Based Heat-Wave Definition

2019 ◽  
Vol 58 (6) ◽  
pp. 1177-1194 ◽  
Author(s):  
Claudia Di Napoli ◽  
Florian Pappenberger ◽  
Hannah L. Cloke

AbstractHeat waves represent a threat to human health and excess mortality is one of the associated negative effects. A health-based definition for heat waves is therefore relevant, especially for early warning purposes, and it is here investigated via the universal thermal climate index (UTCI). The UTCI is a bioclimate index elaborated via an advanced model of human thermoregulation that estimates the thermal stress induced by air temperature, wind speed, moisture, and radiation on the human physiology. Using France as a test bed, the UTCI was computed from meteorological reanalysis data to assess the thermal stress conditions associated with heat-attributable excess mortality in five cities. UTCI values at different climatological percentiles were defined and evaluated in their ability to identify periods of excess mortality (PEMs) over 24 years. Using verification metrics such as the probability of detection (POD), the false alarm ratio (FAR), and the frequency bias (FB), daily minimum and maximum heat stress levels equal to or above corresponding UTCI 95th percentiles (15° ± 2°C and 34.5° ± 1.5°C, respectively) for 3 consecutive days are demonstrated to correlate to PEMs with the highest sensitivity and specificity (0.69 ≤ POD ≤ 1, 0.19 ≤ FAR ≤ 0.46, 1 ≤ FB ≤ 1.48) than minimum, maximum, and mean heat stress level singularly and other bioclimatological percentiles. This finding confirms the detrimental effect of prolonged, unusually high heat stress at day- and nighttime and suggests the UTCI 95th percentile as a health-meaningful threshold for a potential heat-health watch warning system.

2021 ◽  
Author(s):  
Chloe Brimicombe ◽  
Claudia Di Napoli ◽  
Rosalind Cornforth ◽  
Florian Pappenberger ◽  
Celia Petty ◽  
...  

<p>Heatwaves have been increasing in frequency, duration, and intensity. They have been the deadliest hydro-meteorology hazard globally for the last 5 years according to the world meteorological organisation. In addition, they are not constrained by geography in the same sense as many other hazards and as such they are borderless. They however receive less attention, research, and funding internationally than other hazards such as floods and storms, effecting how we perceive their risk and their reporting. Here we consider the impact of heatwaves by making use of the Universal Thermal Climate Index (UTCI) for indicating heat stress. The UTCI is a biometeorological index that computes thermal stress using the parameters of 2m temperature, wind speed, mean radiant temperature and relative humidity and a body model, making it a human-centric approach to assessing thermal stress and is skilful for both indicating and forecasting heat hazards. Further a comparison to how heat impacts are reported in EM-DAT (an international disasters database) and international meteorological organisation reports, supplemented by English news media reports is made to assess whether heat impacts are sufficiently reported. In addition, we refer to specific case studies of the United Kingdom, Ghana, and Uganda to further explore impacts, risk perception and policy at a country level, because although heat is borderless impacts occur on a local scale. All this together, will provide the evidence for the development a potentially global early warning system and the implementation of climate change adaptation on a local level to build adaptive capacity and resilience to the growing risk of heat stress internationally. </p>


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mahamat Abdelkerim Issa ◽  
Fateh Chebana ◽  
Pierre Masselot ◽  
Céline Campagna ◽  
Éric Lavigne ◽  
...  

Abstract Background Many countries have developed heat-health watch and warning systems (HHWWS) or early-warning systems to mitigate the health consequences of extreme heat events. HHWWS usually focuses on the four hottest months of the year and imposes the same threshold over these months. However, according to climate projections, the warm season is expected to extend and/or shift. Some studies demonstrated that health impacts of heat waves are more severe when the human body is not acclimatized to the heat. In order to adapt those systems to potential heat waves occurring outside the hottest months of the season, this study proposes specific health-based monthly heat indicators and thresholds over an extended season from April to October in the northern hemisphere. Methods The proposed approach, an adoption and extension of the HHWWS methodology currently implemented in Quebec (Canada). The latter is developed and applied to the Greater Montreal area (current population 4.3 million) based on historical health and meteorological data over the years. This approach consists of determining excess mortality episodes and then choosing monthly indicators and thresholds that may involve excess mortality. Results We obtain thresholds for the maximum and minimum temperature couple (in °C) that range from (respectively, 23 and 12) in April, to (32 and 21) in July and back to (25 and 13) in October. The resulting HHWWS is flexible, with health-related thresholds taking into account the seasonality and the monthly variability of temperatures over an extended summer season. Conclusions This adaptive and more realistic system has the potential to prevent, by data-driven health alerts, heat-related mortality outside the typical July–August months of heat waves. The proposed methodology is general and can be applied to other regions and situations based on their characteristics.


2019 ◽  
Vol 76 (Suppl 1) ◽  
pp. A73.2-A73
Author(s):  
Matthias Otto ◽  
Tord Kjellstrom ◽  
Bruno Lemke

Exposure to extreme heat negatively affects occupational health. Heat stress indices like Wet Bulb Globe Temperature (WBGT) combine temperature and humidity and allow quantifying the climatic impact on human physiology and clinical health. Multi-day periods of high heat stress (aka. heat waves) affect occupational health and productivity independently from the absolute temperature levels; e.g. well-documented heat-waves in Europe caused disruption, hospitalisations and deaths (2003 French heat wave: more than 1000 extra deaths, 15–65 years, mainly men) even though the temperatures were within the normal range of hotter countries.Climate change is likely to increase frequency and severity of periods of high heat stress. However, current global grid-cell based climate models are not designed to predict heat waves, neither in terms of severity or frequency.By analysing 37 years of historic daily heat index data from almost 5000 global weather stations and comparing them to widely used grid-cell based climate model outputs over the same period, our research explores methods to assess the frequency and intensity of heat waves as well as the associated occupational health effects at any location around the world in the future.Weather station temperature extreme values (WBGT) for the 3 hottest days in 30 years exceed the mean WBGT of the hottest month calculated from climate models in the same grid-cell by about 2 degrees in the tropics but by 10 degrees at higher latitudes in temperate climate regions.Our model based on the relationship between actual recorded periods of elevated heat-stress and grid-cell based climate projections, in combination with population and employment projections, can quantify national and regional productivity loss and health effects with greater certainty than is currently the case.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Hanna Leona Lokys ◽  
Jürgen Junk ◽  
Andreas Krein

Projected climate change will cause increasing air temperatures affecting human thermal comfort. In the highly populated areas of Western-Central Europe a large population will be exposed to these changes. In particular Luxembourg—with its dense population and the large cross-border commuter flows—is vulnerable to changing thermal stress. Based on climate change projections we assessed the impact of climate change on human thermal comfort over the next century using two common human-biometeorological indices, the Physiological Equivalent Temperature and the Universal Thermal Climate Index. To account for uncertainties, we used a multimodel ensemble of 12 transient simulations (1971–2098) with a spatial resolution of 25 km. In addition, the regional differences were analysed by a single regional climate model run with a spatial resolution of 1.3 km. For the future, trends in air temperature, vapour pressure, and both human-biometeorological indices could be determined. Cold stress levels will decrease significantly in the near future up to 2050, while the increase in heat stress turns statistically significant in the far future up to 2100. This results in a temporarily reduced overall thermal stress level but further increasing air temperatures will shift the thermal comfort towards heat stress.


2020 ◽  
Author(s):  
Mahamat Abdelkerim Issa ◽  
Fateh Chebana ◽  
Pierre Masselot ◽  
Celine Campagna ◽  
Éric Lavigne ◽  
...  

Abstract BackgroundMany countries have developed heat-health watch and warning systems (HHWWS) or early-warning systems in an attempt to mitigate the health consequences of extreme heat events. HHWWS usually focus on the four hottest months of the year and impose the same threshold over these months. However, according to climate projections, hot season is expected to extend and/or shift. Some studies demonstrated that health impacts of heat waves are more severe when the human body is not acclimatized to heat. In order to adapt those systems to potential heat waves occurring outside the hottest months of the season, this study proposes specific health-based monthly heat indicators and thresholds over an extended season from April to October in the northern hemisphere. MethodsThe proposed approach, an extension of the HHWWS methodology currently adopted in the province of Quebec, Canada, was developed in the Greater Montreal area (current population 4.3 million) based on historical health and meteorological data over the years. This approach consists of determining excess mortality episodes and then choosing indicators and thresholds that may involve excess mortality.ResultsWe obtain thresholds for the maximum and minimum temperature couple (in °C) that range from (23 and 12, respectively) in April, to (32 and 21) in July and back to (25 and 13) in October. The resulting HHWWS is flexible, with health-related thresholds taking into account the seasonality as well as the monthly variability of temperatures in the threshold definition process for an extended summer season. ConclusionsThis adaptive system has the potential to prevent, by data-driven health alerts, heat-related mortality outside the typical July-August months of heat waves. The proposed methodology is general and can be applied or adapted to other regions and situations.


Author(s):  
Marco Morabito ◽  
Alessandro Messeri ◽  
Pascal Noti ◽  
Ana Casanueva ◽  
Alfonso Crisci ◽  
...  

Existing heat–health warning systems focus on warning vulnerable groups in order to reduce mortality. However, human health and performance are affected at much lower environmental heat strain levels than those directly associated with higher mortality. Moreover, workers are at elevated health risks when exposed to prolonged heat. This study describes the multilingual “HEAT-SHIELD occupational warning system” platform (https://heatshield.zonalab.it/) operating for Europe and developed within the framework of the HEAT-SHIELD project. This system is based on probabilistic medium-range forecasts calibrated on approximately 1800 meteorological stations in Europe and provides the ensemble forecast of the daily maximum heat stress. The platform provides a non-customized output represented by a map showing the weekly maximum probability of exceeding a specific heat stress condition, for each of the four upcoming weeks. Customized output allows the forecast of the personalized local heat-stress-risk based on workers’ physical, clothing and behavioral characteristics and the work environment (outdoors in the sun or shade), also taking into account heat acclimatization. Personal daily heat stress risk levels and behavioral suggestions (hydration and work breaks recommended) to be taken into consideration in the short term (5 days) are provided together with long-term heat risk forecasts (up to 46 days), all which are useful for planning work activities. The HEAT-SHIELD platform provides adaptation strategies for “managing” the impact of global warming.


Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 163
Author(s):  
Bartłomiej Miszuk

Heat stress is one of the most critical factors affecting human life. In Central Europe, its influence is noticeable, especially in the Polish–Saxon region, which is a very popular tourist region also inhabited by a high number of elders. The main goal of this paper was to assess multi-annual changes in heat stress occurring in the region, considering the frequency of heat days, the UTCI (Universal Thermal Climate Index), and circulation conditions. The research showed that all the thermal and biothermal indices in this region significantly increased during 1971–2019 in the lowlands, the mountain foreland, and the lower mountain zone. In terms of the UTCI, a negative trend for cold stress frequency was noticed in the entire region in favor of an increase in a tendency toward thermoneutral conditions and heat stress. This concerns especially strong and very strong heat stress (UTCI > 32 °C), in which positive trends were observed for most of the stations located in the lower hypsometric zones. The results also showed that heat stress mainly occurs on days with anticyclonic circulation. Analysis of selected cases of heat waves in the 21st century indicated that the lower hypsometric zones are characterized by a very high UTCI, while the summit zone is free from heat stress occurrence.


Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 707
Author(s):  
Jacinta Collado-González ◽  
Maria Carmen Piñero ◽  
Ginés Otálora ◽  
Josefa López-Marín ◽  
Francisco M. del Amor

This work has been focused on the study of how we can affect the short heat stress on the bioactive compounds content. Some recent investigations have observed that management of nitrogen fertilization can alleviate short-term heat effects on plants. Additionally, the short-term heat stress can be also ameliorated by using putrescine, a polyamine, due to its crucial role in the adaptation of plants to heat stress Therefore, different NO3−/NH4+ ratios and a foliar putrescine treatment have been used in order to increase tolerance to thermal stress in order to take advantage of the more frequent and intense heat waves and make this crop more sustainable. So, other objective of this work is to make the cauliflower waste more attractive for nutraceutical and pharmaceutical preparations. Thus, the effect of a thermal stress combined with a 50:50 NO3−/NH4+ ratio in the nutrient solution, and the foliar application of 2.5 mM putrescine increased in the content of various sugars (inositol, glucose, and fructose), total phenolic compounds and polyamines, as well as in the antioxidant activity. The greatest accumulation of these compounds was observed in young leaves. Our results show from a physiological and agronomic point of view, that the foliar application of putrescine and the 50:50 NO3−/NH4+ treatment managed to alleviate the negative effects of the abiotic stress suffered at high temperature, yielding plants with higher antioxidant compounds content.


2020 ◽  
Vol 92 (3) ◽  
pp. 361-376
Author(s):  
Monika Okoniewska

This article seeks to analyse the universal thermal climate index (UTCI, °C), in order to characterise hazards associated with high air temperature that may possibly occur in Poland around noon on very hot days. Values for the index (calculated for UTC by reference to air temperature (°C), relative humidity (%), wind speed (v∙ms-1) and cloudiness (%)) related to from the Polish cities of Kołobrzeg, Poznań and Kraków, and to the period 2001–2018. Mean values with standard deviations were calculated, with minimum and maximum values noted, amplitudes, lower and upper quartiles and the skewness coefficient. One-way analysis of variance was deployed to determine whether UTCI values at midday on very hot days differ significantly from month to month. The frequency of occurrence of different intensities of heat stress was also determined. In each case, analysis related to both the overall period and individual years. Hours around noon on very hot days were mainly associated with “moderate” or “severe” heat stress, though instances “very sever heat stress” may also arise. The greatest threat of thermal heat stress could be noted for July and August, with conditions noticeably more severe in Kraków than the other stations studied. Kołobrzeg faced the most-limited hazard associated with the occurrence of heat stress, and only in July may “very severe heat stress” appear there sporadically. In turn, Poznań – located in a region with bioclimatic conditions typical for Poland – was rather characterised by “moderate” or “severe heat stress”. Equally, on a majority of the very hot days studied, all three stations recoded above-average UTCI values, with this fact making it clear that when a high level of thermal stress arises it may be rather a country-wide phenomenon. The most stable, near-average conditions characterised May, while biothermal differentiation peaked in July and August. Analysis of variance showed that, other than in relation to April in Poznań, levels of thermal stress on hot days did not differ significantly from one month to another. Analyses of the variability to values for the multi-year universal thermal climate index revealed an increase over time for maxima, especially in Kraków. This may point to an intensified risk associated with overheating of the body, in the south of Poland in particular. In addition, calculations confirm both spatial and temporal differentiation of biothermal conditions. Years in which hot days proved particularly burdensome were 2005, 2007, 2010 and 2013.


2021 ◽  
Vol 94 (2) ◽  
pp. 201-222
Author(s):  
Milica Pecelj ◽  
Anna Błażejczyk ◽  
Nemanja Vagić ◽  
Peca Ivanović

The study deals with an assessment and interpretation of the bioclimatic conditions in Vranje (southern Serbia). The study aims at temporal distributions of bioclimatic conditions focussing on extreme thermal stress based on the Universal Thermal Climate Index (UTCI). The meteorological data required for the calculation of UTCI concern hourly (7 and 14 CET) weather data collected for the period 2000-2017. The frequency of very strong heat stress (VSHS), very strong cold stress (VSCS) and extreme cold stress (ECS) for both morning and midday hours. Furthermore, the daily difference of the UTCI hourly values (diurnal UTCI change) are specified, giving the daily variance of heat and cold stress. The results revealed the frequency of days in which thermal stress prevails for the studied period. The obtained results show an increase in extreme heat biothermal conditions, while extreme cold biothermal conditions are in decline, especially in the last 10 years. However, the frequency (the number of days) of very strong heat stress (VSHS) increased since 2007. A spectacular increase in heat stress was observed in the month of September, particularly in 2015.


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