Inter-spatial heat vulnerability assessment of Summer - 2018 over Madhya Pradesh using discomfort (wind and thermal) indices

Due to global warming, increase in air temperature is a growing concern at present. This rise in temperature may cause mild to severe thermal discomfort and heat related hazards mostly for the people who are engaged in outside activities throughout the day. The present study shows the inter-spatial monthly distribution of thermal patches over major stations of Madhya Pradesh, viz., Bhopal, Gwalior, Indore, Jabalpur, Hoshangabad, Rewa, Ratlam, Ujjain, Dhar etc. In this study, various Heat Indices applicable for tropical climate including Wet Bulb Globe Temperature (WBGT) are used to estimate the thermal stress by analyzing the meteorological data of Summer-2018 in Madhya Pradesh. Study was carried out for computing indoor, shady and outdoor heat stress separately and heat transfer rates to identify the places vulnerable to severe heat stroke in the month of March, April and May in 2018.It is observed that declaration of heat wave alone at any station is not sufficient for the administration and health organizations to take precautionary actions; also, discomfort indices should be referred for impact based monitoring and making work schedules. It is found that March and April fall in the partial discomfort category for at least half of the districts in Madhya Pradesh. It is interesting to note that several districts fall in discomfort category in outdoor conditions but not in indoor or shady conditions in May month. Severe stresses are observed mainly in the West and Central Madhya Pradesh during April and May months. Comparison of various Heat Indices is too performed along with computing Tropical Summer Index (TSI) and Apparent Temperature (AT) to indicate real feel-like temperatures in Madhya Pradesh during extreme temperature events.

The heat is on: Observations and trends of heat stress metrics during Florida summers

Extreme heat is annually the deadliest weather hazard in the U.S. and is strongly amplified by climate change. In Florida, summer heat waves have increased in frequency and duration, exacerbating negative human health impacts on a state with a substantial older population and industries (e.g., agriculture) that require frequent outdoor work. However, the combined impacts of temperature and humidity (heat stress) have not been previously investigated. For eight Florida cities, this study constructs summer climatologies and trend analyses (1950–2020) of two heat stress metrics: heat index (HI) and wet bulb globe temperature (WBGT). While both incorporate temperature and humidity, WBGT also includes wind and solar radiation, and is a more comprehensive measure of heat stress on the human body. With minor exceptions, results show increases in average summer daily maximum, mean, and minimum HI and WBGT throughout Florida. Daily minimum HI and WBGT exhibit statistically significant increases at all eight stations, emphasizing a hazardous rise in nighttime heat stress. Corresponding to other recent studies, HI and WBGT increases are largest in coastal subtropical locations in Central and South Florida (i.e., Daytona Beach, Tampa, Miami, Key West), but exhibit no conclusive relationship with urbanization changes. Finally, danger (103–124°F) HI and high (> 88°F) WBGT summer days exhibit significant frequency increases across the state. Especially at coastal locations in the Florida Peninsula and Keys, danger HI and high WBGT days now account for > 20% of total summer days, emphasizing a substantial escalation in heat stress, particularly since 2000.

Bioclimatic performance of wet coffee processing facilities: conditions for workers and coffee

This study aimed to evaluate the bioclimatic performance of three wet coffee processing facilities in Colombia, focused on the conditions for workers and coffee parchment, through computer simulation. In addition to temperature and relative humidity, the Wet-Bulb Globe Temperature index (WBGT) was simulated during the highest coffee production month. The proposed simulation model was able to predict hygrothermal behavior within the three coffee processing facilities. Case 3 presented the warmest environment, and case 2 the most humid environment concerning the appropriate conditions for the coffee and the worker. The WBGT index limit was exceeded in case 3. Since this type of facility emits large amounts of heat and steam, constructive modifications are suggested to improve the environmental conditions of workers and coffee. Mainly, the physical separation of the heat exchangers is recommended, which ideally should be outside the post-harvest facility. The steam produced in the drying process should be quickly evacuated with ventilation strategies. Additionally, the use of strategies that reduce the energy gain from solar radiation is suggested.

Trend Analysis and Temporal and Spatial Distribution of Wet Bulb Globe Temperature as a Heat Stress Index in Iran during the Summer Season over a 30-year Period

Introduction: Global warming is one of the most important environmental problems that have raised researchers’ attention. The present study aimed to analyze heat stress trends using the Wet Bulb Globe Temperature (WBGT) index in the country of Iran during the summer over a 30-year period. Materials and Methods: Daily summertime statistical data regarding mean temperature and mean relative humidity, taken from 40 synoptic meteorological stations across Iran during a 30-year period were obtained from the Iranian National Meteorological Department. The De Martonne climate classification system was used to categorize various climate regions of Iran. The WBGT index was calculated using the formula given by the Australian Bureau of Meteorology. The Mann-Kendall statistical test and the Sen's slope estimator were used to analyze the trends of the WBGT index. Results: The WBGT index had an upward trend during the three months of June, July, and August in 71.42%, 57.14%, and 66.66% of all stations and this trend was statistically significant in 53.32%, 50%, and 42.85% of those stations, respectively. Moreover, throughout the summer, 45% of the WBGT index measurements were in the medium range (18-23°C), 37.5% were in the high range (23-28°C), and 17.5% were in the very high range (> 28°C). Conclusion: The WBGT index followed an upward trend during the summer, especially in semi-arid regions of Iran. Considering the phenomenon of global warming, it is essential to monitor, plan ahead, and take necessary precaution measures for sensitive populations who are at high risk areas of the country.

Assessing the Climatological Relationship between Heatstroke Risk and Heat Stress Indices in 47 Prefectures in Japan

This study provides a decade-long link between summer heatstroke incidence and certain heat stress indices in 47 prefectures of Japan. The results for each prefecture were determined from the age-adjusted heatstroke incidence rate (TRadj) with heatstroke patients transported by ambulance, as well as from the daily maximum temperature (TEMPmax), maximum wet-bulb globe temperature (WBGTmax), and maximum universal thermal climate index (UTCImax) recorded from July to September of 2010–2019. The UTCImax relatively increased the vulnerability in many prefectures of northern Japan more distinctly than the other indices. In the following analysis, the ratio of the TRadj of the hottest to coolest months using the UTCImax was defined as the heatstroke risk of the hottest to coolest (HRHC). Overall, the HRHC varied approximately from 20 to 40 in many prefectures in the past decade. In contrast, for the same analysis performed in each month, HRHC ratios in July and August fell within 2–4 in many prefectures, whereas in September, the average and maximum HRHC ratios for all prefectures were 7.0 and 32.4, respectively. This difference can be related to the large difference in UTCImax between the maximum and minimum for a decade.

Identifying the need for locally-observed wet bulb globe temperature across outdoor athletic venues for current and future climates in a desert environment

Exertional heat illness and stroke are serious concerns across youth and college sports programs. While some teams and governing bodies have adopted the wet bulb globe temperature (WBGT), few practitioners use measurements on the field of play; rather, they often rely on regionally modeled or estimated WBGT. However, urban development-induced heat and projected climate change increase exposure to heat. We examined WBGT levels between various athletic surfaces and regional weather stations under current and projected climates and in hot-humid and hot-dry weather regimes in the southwest U.S. in Tempe, Arizona. On-site sun-exposed WBGT data across five days (07:00–19:00 local time) in June (dry) and August (humid) were collected over five athletic surfaces: rubber, artificial turf, clay, grass, and asphalt. Weather stations data were used to estimate regional WBGT (via the Liljegren model) and compared to on-site, observed WBGT. Finally, projected changes to WBGT were modeled under mid-century and late-century conditions. On-field WBGT observations were, on average, significantly higher than WBGT estimated from regional weather stations by 2.4°C–2.5°C, with mean on-field WBGT across both months of 28.52.76°C (versus 25.83.21°C regionally). However, between-athletic surface WBGT differences were largely insignificant. Significantly higher mean WBGTs occurred in August (30.12.35°C) versus June (26.92.19°C) across all venues; August conditions reached ‘limit activity’ or ‘cancellation’ thresholds for 6–8 hours and 2–4 hours of the day, respectively, for all sports venues. Climate projections show increased WBGTs across measurement locations, dependent on projection and period, with average August WBGT under the highest representative concentration pathway causing all-day activity cancellations. Practitioners are encouraged to use WBGT devices within the vicinity of the fields of play, yet should not rely on weather station estimations without corrections used. Heat concerns are expected to increase in the future, underlining the need for athlete monitoring, local cooling design strategies, and heat adaptation for safety.

Performances of Limited Area Models for the WORKLIMATE Heat–Health Warning System to Protect Worker’s Health and Productivity in Italy

Outdoor workers are particularly exposed to climate conditions, and in particular, the increase of environmental temperature directly affects their health and productivity. For these reasons, in recent years, heat-health warning systems have been developed for workers generally using heat stress indicators obtained by the combination of meteorological parameters to describe the thermal stress induced by the outdoor environment on the human body. There are several studies on the verification of the parameters predicted by meteorological models, but very few relating to the validation of heat stress indicators. This study aims to verify the performance of two limited area models, with different spatial resolution, potentially applicable in the occupational heat health warning system developed within the WORKLIMATE project for the Italian territory. A comparison between the Wet Bulb Globe Temperature predicted by the models and that obtained by data from 28 weather stations was carried out over about three summer seasons in different daily time slots, using the most common skill of performance. The two meteorological models were overall comparable for much of the Italian explored territory, while major limits have emerged in areas with complex topography. This study demonstrated the applicability of limited area models in occupational heat health warning systems.

Selecting Thresholds of Heat-Warning Systems with Substantial Enhancement of Essential Population Health Outcomes for Facilitating Implementation

Most heat-health studies identified thresholds just outside human comfort zones, which are often too low to be used in heat-warning systems for reducing climate-related health risks. We refined a generalized additive model for selecting thresholds with substantial health risk enhancement, based on Taiwan population records of 2000–2017, considering lag effects and different spatial scales. Reference-adjusted risk ratio (RaRR) is proposed, defined as the ratio between the relative risk of an essential health outcome for a threshold candidate against that for a reference; the threshold with the highest RaRR is potentially the optimal one. It was found that the wet-bulb globe temperature (WBGT) is a more sensitive heat-health indicator than temperature. At lag 0, the highest RaRR (1.66) with WBGT occurred in emergency visits of children, while that in hospital visits occurred for the working-age group (1.19), presumably due to high exposure while engaging in outdoor activities. For most sex, age, and sub-region categories, the RaRRs of emergency visits were higher than those of hospital visits and all-cause mortality; thus, emergency visits should be employed (if available) to select heat-warning thresholds. This work demonstrates the applicability of this method to facilitate the establishment of heat-warning systems at city or country scales by authorities worldwide.