Hot Months Research Articles

Using satellite-derived land surface temperatures to clarify the spatiotemporal warming trends of the Alborz Mountains in northern Iran

The Alborz Mountains are some of the highest in Iran, and they play an important role in controlling the climate of the country’s northern regions. The land surface temperature (LST) is an important variable that affects the ecosystem of this area. This study investigated the spatiotemporal changes and trends of the nighttime LST in the western region of the Central Alborz Mountains at elevations of 1500–4000 m above sea level. MODIS data were extracted for the period of 2000–2021, and the Mann–Kendall nonparametric test was applied to evaluating the changes in the LST. The results indicated a significant increasing trend for the monthly average LST in May–August along the southern aspect. Both the northern and southern aspects showed decreasing trends for the monthly average LST in October, November, and March and an increasing trend in other months. At all elevations, the average decadal change in the monthly average LST was more severe along the southern aspect (0.60°C) than along the northern aspect (0.37°C). The LST difference between the northern and southern aspects decreased in the cold months but increased in the hot months. At the same elevation, the difference in the lapse rate between the northern and southern aspects was greater in the hot months than in the cold months. With increasing elevation, the lapse rate between the northern and southern aspects disappeared. Climate change was concluded to greatly decrease the difference in LST at different elevations for April–July.

Aleksandry Czechówny dwie wyprawy „do wód” – do Iwonicza (1875 r.) i Szczawnicy (1880 r.). Wybór z „Dziennika”

Aleksandra Czechówna’s two trips “To the waters”– to Iwonicz (1875) and Szczawnica (1880) (Selected Works) Aleksandra Apolonia Czechówna (1839–1923) was the daughter of Tomasz Czech and Aleksandra nee Zielińska. The journal she was writing for her entire life – almost un interruptedly for 68 years (1856–1923) is kept in the National Archive in Krakow under file no. 29/1582/1–29/1582/44 (former file no. IT 428/1–428/44). It is a great source pre senting cultural and social life of Krakow during the second half of 19th century and first two decades of the 20th century. During hot summer months people were willing to leave the city. They would often go to the countryside but also the “the waters” – spa towns, which offered not only a ther apeutic activity but also leisure and entertainment. Numerous doctors were more and more often promoting spa treatment. Aleksandra Czechówna, living in Krakow, was also trying to spend the dog days of summer away from the city. She would often visit her family in the countryside or go for trips around Krakow. But to help her health or just accompanying her parents, several times she had also a chance to visit spa towns, mostly Polish ones but also abroad. The presented two accounts from Aleksandra Czechówna’s trips to “the baths” – to Iwonicz in 1875 and to Szczawnica 1880, create an interesting contributory studies of the daily life of that times when the habit of holiday trips and spa treatment was emerging and developing dynamically. The text comes from two volumes of Aleksandra Czechówna’s “Journal”: vol. 14 file no. 29/1582/14 (former file no. IT 428/14) and vol. 18, file no. 29/1582/18 (former file no. IT 428/18).

Exploring future trends of precipitation and runoff in arid regions under different scenarios based on a bias-corrected CMIP6 model

Precipitation and runoff changes play a very important role in ecosystems and human well-being. Predicting its changes is critical for water resource management and coping with climate change. However, corresponding studies in arid regions are limited by lack of data and poor spatial distribution of meteorological stations. Therefore, this study identified the applicability of multi-source meteorological data in a typical arid region, the Shiyang River Basin, by comparing its variability with measured precipitation. Then, the best applicable precipitation product was selected to correct the data of CMIP6, and to predict the change of precipitation and runoff under the scenarios of SSP126/245/585 by 2100. The results showed that the CMADS dataset was more consistent with the measured data than TRMM and CFSR. Through Taylor diagram analysis and equidistant cumulative distribution functions matching (EDCDF) method bias correction, the GFDL-ESM4 model was more suitable for arid regions in terms of precipitation and temperature. During 2015–2100, the annual precipitation and average annual temperature under each scenario all showed an increasing trend. However, the monthly precipitation from May to October showed a decreasing trend, indicating an increase in precipitation during spring and winter, and a decrease during summer and autumn. The average temperature for all months from January to December showed an increasing trend. However, in arid regions, the temperature increase is more pronounced during colder months (1–3) compared to hotter months (6–9). The average annual runoff of SSP126 scenario showed an increasing trend from 2015 to 2100 (SSP126: 0.004/yr), while the runoff from the SSP245 and SSP585 scenarios showed a decreasing trend (SSP245: −0.031/yr; SSPSSP585: −0.084/yr). This is primarily attributed to a small increment of precipitation and a larger increment of temperature, an early melting of glacial snow and an increasing of evapotranspiration, which in turn leads to a reduction in annual runoff. The research can help achieving sustainable development, effective management of water resources in arid regions, and provide a reference and example for related research in high-resolution.

Foliar application of diethyl aminoethyl hexanoate (DA‐6) alleviated summer bentgrass decline and heat damage to creeping bentgrass

AbstractCreeping bentgrass (Agrostis stolonifera) is sensitive to supra‐optimal temperature, which makes summer bentgrass decline (SBD) a main conundrum troubling turf manager. Diethyl aminoethyl hexanoate (DA‐6) is an artificial and bioactive plant growth regulator affecting tolerance to various abiotic stresses. It is commercially available for field application due to multiple advantages such as low cost, environmentally friendly compound, and sustainable effect. However, the positive effect and mechanism of DA‐6‐mediated heat tolerance in cool‐season grass species and SBD are not yet been explored. Objectives of the study were to screen the optimal dose of DA‐6 for improvement in thermotolerance and to investigate roles of DA‐6 in regulating photosynthesis, osmotic balance, and antioxidant homeostasis in two creeping bentgrass cultivars (heat‐tolerant 13 M and heat‐sensitive Seaside II) in controlled heat condition. Summer heat tolerance induced by the DA‐6 was further evaluated for 2 years under field conditions in a subtropical zone. Results demonstrated that the optimal dose of DA‐6 was screened as 0.1 mM based on analyses of chlorophyll content, photochemical efficiency, and cell membrane stability under heat stress. Foliar application of DA‐6 significantly alleviated heat‐induced leaf senescence by improving photosynthetic performance, accumulation of sugars (sucrose, fructose, and glucose) for osmotic homeostasis, and total antioxidant capacity for reactive oxygen species scavenging in the two cultivars. A 2‐year field test was further carried out to demonstrate that turf quality of the two cultivars was significantly improved after being treated by foliar DA‐6 during hot summer months in 2020 and 2021. Current findings suggested that DA‐6‐mediated thermo‐resistant mechanism was associated with photosynthesis, osmotic adjustment, and antioxidant in cool‐season grass species. Foliar application of DA‐6 could be a cheap, effective, and environmentally friendly strategy to alleviate SBD.

The Impact of Climate Change on Aeromedical Retrieval Services in Remote Northern Australia: Planning for a Hotter Future.

It is known that environmental heat is associated with increased morbidity manifesting as increasing demand on acute care health services including pre-hospital transport and emergency departments. These services play a vital role in emergency care, and in rural and remote locations, where resource capacity is limited, aeromedical and other retrieval services are a vital part of healthcare delivery. There is no research examining how heat impacts remote retrieval service delivery. The Northern Territory (NT) of Australia is characterised by very remote communities with limited acute healthcare capacities and is a region subject to regular extreme tropical heat. In this study, we examine the relationship between aeromedical retrievals and hot weather for all NT retrievals between February 2018 and December 2019. A regression analysis was performed on the number of retrievals by clinical reason for retrieval matched to the temperature on the day of retrieval. There was a statistically significant exposure response relationship with increasing retrievals of obstetric emergencies in hotter weather in the humid climate zone and surgical retrievals in the arid zone. Retrieval services appeared to be at capacity at all times of the year. Given that there are no obstetric services in remote communities and that obstetric emergencies are a higher triage category than other emergencies (i.e., more urgent), such an increase will impede overall retrieval service delivery in hot weather. Increasing surgical retrievals in the arid zone may reflect an increase in soft tissue infections occurring in overcrowded houses in the hotter months of the year. Given that retrieval services are at capacity throughout the year, any increase in demand caused by increasing environmental heat will have broad implications for service delivery as the climate warms. Planning for a hotter future must include building resilient communities by optimising local healthcare capacity and addressing housing and other socioeconomic inequities that amplify heat-related illness.

Effect of breeding season and age on follicular dynamics and hemodynamics in embryo donor mares subjected to luteolysis after embryo flushing.

Mares are the only companion animals simulating women in the large diameter of their follicles. Horses start reproduction at the age of three years, and some of them live for >30 years, so aging influences their reproductive capacity. Mares are sensitive to summer heat stress as they can sweat like humans. The current work aimed to study the effects of age (young versus senile), season (cold versus hot), and the hormonal treatments during embryo collection on the dominant and subordinate follicular dynamics and hemodynamics and circulating ovarian hormones in embryo donor mares ovulated twice spontaneously before inducing ovulation for flushing embryos. Spontaneous oestrous cycles were studied for young mares (<10 years; N = 6) or senile (>20 years; N = 5) during months of the cold season (November to April) and hot season (May to August). In young embryo donor mares, oestrous cycles after inducing ovulation and luteolysis were studied using Doppler ultrasound. Estradiol (E2), progesterone (P4), nitric oxide (NO), total cholesterol, and lactate dehydrogenase (LDH) were measured in blood serum. A decrease in the dominant follicle antrum diameter (p > 0.05) and LDH (p = 0.016) was observed after inducing luteolysis in young embryo donor mares. Both human chorionic gonadotropin (hCG) and PGF2α treatments increased dominant follicle area (p = 0.0001), antrum area (p = 0.001), perimeter (p = 0.001), granulosa area (p = 0.0001), cholesterol (p = 0.0001), NO (p = 0.0001), and E2 (p = 0.0001). The dominant follicle area, antrum area, perimeter, color area, granulosa area, LDH, cholesterol, NO, and E2 increased (p = 0.0001) during the oestrous cycles of the hot season, but the circulatory % (p = 0.0001) declined. Senile mares had lower dominant follicle area (p = 0.002), antrum area (p = 0.0001), granulosa area (p > 0.05), LDH (p = 0.001), cholesterol (p = 0.0001), NO (p = 0.0001), and E2 (p = 0.0001) but higher circulatory % (p = 0.0001) and color area % (p = 0.023). The dominant follicle possesses the largest diameter, area, perimeter, granulosa area, and color area but the lowest circulatory % during spontaneous oestrous cycles, after inducing ovulation, or luteolysis with significant effects of the day of the spontaneous oestrous cycles on their dynamics and hemodynamics. During hot months, mares treated with hCG ovulated 24 hours later and prostaglandin-induced luteolysis was followed by new ovulation five days later. Follicles ovulated during the hot months were larger than those ovulated during the cold months and both had nearly the same color area %. Senile mares ovulated follicles with a lower area and antrum area but a higher color area %, so senile mares can be used as embryo or oocyte donors during the hot season.

Driving sustainability: IoT sensor integration for efficient car AC control

The Car AC Control Using IoT Sensor. The interior temperature of the car rapidly increases mostly during the hot summer months. This paper aims to address the challenge of maintaining a comfortable interior temperature in car, especially during hot summer months. To overcome this problem a mobile application is developed which helps to monitor the temperature in the car by using the Internet of Things (IoT). With this application the AC can be switched ON before getting into the car as the AC controller is linked to the mobile application. To power the system, a lithium-ion battery is used, which is recharged by the conversion of kinetic energy generated by the vehicle's movement, particularly from the wingtips. The intelligent design of air conditioners will ensures the efficient energy consumption with which the battery life can be prolonged. The proposed method will monitor the temperature inside the car.

Nitrogen and carbon cycling and relationships to radium behavior in porewater and surface water: Insight from a dry year sampling in a hypersaline estuary

Biogeochemical transformations within highly saline subterranean estuaries (STE) dramatically affect solute cycling, resulting in submarine groundwater discharge (SGD) with distinct chemical signatures. The study hypothesizes that biogeochemical processes within hypersaline bay porewaters (PW) simultaneously affect nitrogen, carbon, and radium cycling. We measured radium isotopes (226Ra, 224Ra, and 223Ra), nutrients (dissolved inorganic nitrogen [DIN: NH4+ + NO2− + NO3−], HPO42− [DIP], HSiO3− [DSi], dissolved organic carbon [DOC]), total alkalinity (TA), dissolved inorganic carbon (DIC), stable isotopes, and major cations in PW and surface water (SW) of Baffin Bay, a well-mixed, semi-enclosed estuary along the semiarid northwestern Gulf of Mexico coast, over three seasons in a characteristically dry year. This study's findings show a concurrent increase in NH4+, DIP, DSi, and TA/DIC with reduced metal species (e.g., Mn and Fe) and Ra during the hot and dry seasons, particularly in PW, under increasingly reducing conditions. Principal component analyses (PCA) suggest these increases are primarily driven by dissimilatory nitrate/nitrite reduction to ammonium (DNRA) and dissolution of lithogenic particles and biogenic CaCO3, modulated by organic matter degradation or remineralization. While more significant terrestrial groundwater inputs may contribute to solutes and Ra supply in the STE, the biogeochemically induced variability in solute concentrations in PW primarily drives larger SGD-derived fluxes, particularly notable in hot months. During a typically dry year, these fluxes, estimated as the average of 226Ra and 223Ra mass balance models (e.g., July/November fluxes in Mmol∙d−1: 0.093/0.092 of NO3−; 0.2/0.02 of NO2−; 72/16 of NH4+; 72.2/18 of DIN; 1.5/0.2 of HPO42−; 20/9 of HSiO3−; 42/37 of DOC; 503/399 of TA; 582/431 of DIC) are orders of magnitude (∼4 for DIN and DIC, ∼3 for DIP, DSi, and DOC, and ∼2 for TA) greater than surface runoff inputs. These substantial SGD inputs likely sustain phytoplankton growth and potentially fuel harmful algal blooms while countering estuarine acidification.

A numerical study of cucurbit cultivation in a greenhouse under direct solar radiation and equipped with a direct evaporative cooler in summer season

The performance of direct evaporative cooler to meet cooling demand of a greenhouse in Tehran in the hottest months of the year as well as water and electricity consumption were numerically studied. The suitable values of air change per hour (ACH) was also obtained for cultivation of tomato, cucumber, eggplant and bell peppers. The k-Ԑ Realizable Turbulence and Discrete Ordinates (DO) models was used for simulating the airflow and estimating radiative heat transfer, respectively. The results showed that an ACH of 10 is proper for tomato cultivation. When the ambient temperature is maximal, an ACH of 15 can be used for cucumber cultivation. However, ACH cannot be kept constant, and ACHs of ≤10 should be utilized when the ambient temperature decreases. For eggplants, it is better to use an ACH 20 at hot hours and an ACH of 10 when the temperature declines. For the bell pepper plant, 20 and 10 ACHs are suitable for day and night hours, respectively. Moreover, the maximum daily water consumed in the greenhouse happens in August and equals 222 lit/day for 20 Air Changes per Hour (ACH). The minimum daily water is consumed in July, equaling 106 lit/day for an ACH of 10. In the present study, the electricity rate consumed in the greenhouse equals 127W when ACH = 20, i.e., the consumed electric energy is 3 kWh for the entire system in a 24-h interval.

Effect of hCG and prostaglandin on ovarian, luteal development, and hormonal changes in embryo donor mares during the hot summer months in subtropics.

Commercial embryo flushing of horses has required hormonal management of both the donor and recipient mares throughout the breeding season. This study aimed to find out the effect of using human chorionic gonadotropin (hCG) and prostaglandin F2α (PG) on the ovarian and uterine dynamics and hemodynamics, estradiol (E2), progesterone, oxidants-antioxidants, and blood biochemicals in embryo donor mares during the hottest months of the year in a subtropical climate. Three Control estrous cycles of native mares (10-20 years; N = 10) followed by two treated cycles with hCG and PGF2α were examined daily from May to August using Doppler ultrasound with blood sampling. Circulating, progesterone (P4), total cholesterol, total proteins, albumin, haptoglobin, nitric oxide (NO), catalase, alkaline phosphatase, lactate dehydrogenase (LDH), and myeloperoxidase were measured in blood serum. Days during the control estrous cycle impacted the dominant follicle (DF) diameter ( p < 0.0001), antrum diameter ( p < 0.0001), area ( p < 0.0001), antral area ( p < 0.0001), and color area % (p > 0.05), and corpus luteum (CL) diameter ( p < 0.0001). PG tended to impact DF diameter (p > 0.05) but influenced its antrum diameter (p < 0.05), color area (p < 0.05), CL diameter (p < 0.01), and area (p = 0.013). Days after hCG tended to impact DF antrum diameter (p > 0.05) and the antrum area (p > 0.05), but influenced CL diameter ( p < 0.0001). PGF2α and hCG increased uterine horn area (p = 0.016) and color area (p = 0.023), total cholesterol ( p < 0.0001), and NO ( p < 0.0001) levels but hCG increased the levels of myeloperoxidase (p < 0.005), total proteins (p < 0.001), and albumin ( p < 0.0001). Globulins achieved the highest level (p = 0.054) but the Albumin/globulin ratio reached a minimum value on Day 0 of the control mares ( p < 0.0001). PGF2α increased LDH ( p < 0.0001) and sharply declined (p = 0.028) progesterone. In conclusion, the treatment protocols of hCG and PGF2α showed minimal effects on the produced ovulating follicles and can be used during the summer season to manage embryo donor mares.

Saving Walker Lake: A Pleistocene Terminal Lake in the Anthropocene

Abstract: Just to the east of the Sierra Nevada mountain range a series of Pleistocene terminal lakes are present in the Great Basin of the intermountain West between the Rockies and the Sierra. Among them is Walker Lake, fed by the branches of the Walker River that flow eastward from their snow-melt sources in the Sierra. The terminal lakes have no natural outlets. Water is lost from the lakes' surfaces by evaporation during the hot summer months in the high desert. Since the arrival of Euro-Americans in the nineteenth century, the diversion of water for agricultural, industrial, and domestic uses from the Walker River has reduced the level of the lake to a point where it no longer supports a once-thriving fishery of native cutthroat trout. In the past, western Nevada Paiute peoples relied on the lake's fish as a food source. In the twentieth century the inland anadromous trout drew sports fishing enthusiasts. Climate change has caused additional strains on the water supply for the lake to the point where many have declared Walker Lake a dead lake with only shrinking shorelines and increased salinization in its future. In response, Nevada's U.S. senator Harry Reid, members of the Walker River Indian Reservation, sport fishing organizations, as well as environmental organizations pushed for legislation from Congress to promote efforts to save the lake in the 1990s. These efforts have produced some promising results.

Assessment of the temperature and humidity index (THI) to facilitate the establishment of a ruminant rearing system in Bangladesh

The objective of this study was to assess the temperature-humidity index (THI) values in the selected regions of Bangladesh for the suitability of ruminant rearing. Data on monthly temperatures and relative humidity were collected from the Bangladesh Meteorological Department (BMD) for a 27-year time period (1995–2022). The study region’s data indicated that the hottest area was west central region and hottest month was June. In comparison, the coolest area was northwest region and coolest month was January. The northwest region had no heat stress from November to February, mild heat stress from March to May and October, as well as moderate heat stress from June to September. In the northeast region, mild heat stress occurred from March to May, October, and November, and moderate heat stress from June to September. December to February were comfortable, March, October, and November were mild heat stress, and April through September were moderate heat stress in the west central region. In the east central region, mild heat stress occurred in March to April, October, and November, and severe heat stress in May to September. In contrast to the west central region, which showed moderate heat stress during the rainy season, most other seasons showed mild heat stress. Thus, heat stress periods might vary depending on regional meteorological scenarios. Animals faced heat stress (THI &gt; 72) or a warning signal due to a progressive increase in temperature and humidity indices over months and years of investigation. When THI levels are high, especially in July and August, livestock farmers must emphasize various herd management techniques to limit the risk of milk production and quality concerns, disease prevalence, and reproductive performance. The findings of the present investigation suggest heat stress mitigation measures for Bangladeshi ruminant farmers. Ann. Bangladesh Agric. 27 (2): 161-174

Effect of GnRH on the day of Insemination on Ovulatory Response in Crossbred Cows

The effect of gonadotropin releasing hormone (GnRH) analogue on the ovulatory response of oestrual follicle during cold and hotter months of the year was studied. A total of 120 crossbred cows brought for insemination with oestrus signs during colder months (December 2022 –January 2023; n=52) and hotter months (April – May 2023; n=68) to the Gynaecology Unit of Veterinary Clinical Complex, Veterinary College and Research Institute, Orathanadu were utilized for the study. Oestrus (Day 0) was confirmed by gynaeco-clinical and ultrasound examination and animals were inseminated with (n =33) or without (n = 87) GnRH (Buserelin acetate 10 mcg; im). The biometry of oestrual follicle (OF) and regressing corpus luteum (RCL) were measured ultrasonographically on Day 0 and the OF was observed every 24 hours until ovulation. The diameter of the OF on Day 0 was non-significantly (P &gt; 0.05) larger during hotter months (12.19 ± 0.21 mm) than colder months (11.58 ± 0.32 mm). There were no significant (P &gt; 0.05) differences in the diameter of RCL between the two periods (9.63 ± 0.21 and 9.56 ± 0.22 mm respectively). OFs were observed majorly in the right ovary during the hotter (60.76%) and colder (54.17%) months. Ovulations occurred on the mean days of 1.00 and 1.37 ± 0.18 in GnRH group during hotter (H-Gn) and colder months (C-Gn) respectively. The respective mean days in non-GnRH group were 1.14 ± 0.05 and 1.33 ± 0.08 during hotter (H-O) and colder months (C-O). In H-Gn group all the animals (100%) ovulated on Day 1, when compared to C-Gn animals (62.50%). On perusing the possible effect of RCL on ovulation, significantly increased percentages of ovulations were observed in OFs on the contralateral ovary to the ovary having the RCL in GnRH group and viceversa in non-GnRH group. It could be assumed that GnRH administration on the day of insemination may be beneficial during the hotter months of the year.

A DIVERSE LIFE IS A BETTER LIFE? THE ASSOCIATION BETWEEN ACTIVITY DIVERSITY AND PSYCHOLOGICAL WELL-BEING IN HONG KONG

Abstract The debate between the devotedness and evenness of activity participation has long existed. On the one hand, the theory of selective optimization with compensation (Baltes &amp; Baltes, 1990) argues that successful aging depends on concentrating one’s participation on fewer domains of activities. On the other hand, the social integration perspective (Rosow, 1967) posits that diversity indicates extensive knowledge and a sense of purpose, which contributes to well-being. A previous study found a positive relationship between activity diversity and older adults’ psychological well-being in a U.S. sample (Lee et al., 2018). However, it might not be the case for people living in extremely hot weather as diverse activities might increase the risk of exposure to the heat. The current study examines their relationship in the hot summer months in Hong Kong, a tropical Asian city. Community-dwelling participants aged 60 years or above (N = 344, Mage = 67.15, SDage = 5.26) completed surveys 3 times each day over 10 days, reporting their activities, positive and negative affect, meaning and engagement of each activity, and loneliness. The regional heat-risk index was acquired from Hua et al. (2021). Results showed that activity diversity negatively correlated with positive affect, meaningfulness and engagement of daily activities, and positively correlated with loneliness. Heat risk did not moderate the relationship, but it correlated with less positive and more negative affect. Our findings suggest that Hong Kong older adults benefit from focused rather than broad participation in activities.

Seasonal soil moisture thresholds inhibit bacterial activity and decomposition during drought in a tallgrass prairie

Soil moisture reductions during drought often inhibit soil microbial activity and inhibit decomposition rates by reducing microbial biomass or by altering microbial communities. Evidence suggests that soil water must drop below a critical threshold to inhibit microbial activity. Thus, it is likely that the seasonal timing of drought will determine the extent to which belowground processes are adversely impacted by drought. Specifically, the effects of drought might be minimal during cool, wet periods typical of late spring but dramatic during hot summer months with high evapotranspiration rates that lower soil moisture levels below the critical threshold. Here, we present results from a study designed to quantify the effect of drought on soil microbial abundance, community composition, and soil water diffusion across four months, and to then assess how drought impacts the microbial decomposition of leaf matter. We imposed a season‐long drought in a Wisconsin tallgrass prairie and measured soil moisture, bacterial composition and abundance, microbial respiration, and decomposition rates throughout the growing season. Bacterial communities varied considerably among dates, but drought did not affect either bacterial abundance or community composition. Microbial respiration declined significantly during periods of drought when soil pores likely became hydrologically isolated, ultimately reducing cumulative microbial respiration by 10%. The reduction in microbial activity in drought treatments caused a 50% decline in the decomposition of refractory material. Our study highlights that sublethal effects of drought on microbial communities, occurring only when soil moisture declined below a tolerance threshold, can have large impacts on microbial carbon release or decomposition, highlighting the need to incorporate such measures into future studies.

Impact of a small-scale solar park on temperature and vegetation parameters obtained from Landsat 8

The effects of photovoltaic solar parks on the local environment are a growing topic of interest, as more solar parks are installed worldwide. Most studies focus on large solar parks, as these usually have more availability for both in situ and remote sensing data. Here, remote sensing data of surface temperature and vegetation were used to assess the impact of a relatively small utility-scale solar park (46 MW) in Portugal, in a region with a Mediterranean climate. Results show that the impact translates into a seasonal pattern, with positive surface temperature anomalies during the colder months and negative ones during the summer, which overall reduces the amplitude of the seasonal cycle. Comparing the operational period of the solar park with the one before its installation yields an increase in surface temperature for the control area of 1.74 °C contrasting with a decrease of 0.23 °C in the solar park area, during summertime (JJA). For the winter months (DJF), surface temperature increased for the solar park and control areas, by 0.4 °C and 1.44 °C, respectively. The effect is similar but less pronounced for anomalies in the inferred air temperature. For vegetation, negative anomalies in winter and little to no change during hotter months are observed.

Resurfacing heat stress phenomena in Indian cities during the post‐COVID‐19 lockdown period

This study investigates heat stress in 17 Indian cities during the post‐COVID‐19 lockdown period. The study compares thermal comfort experienced during the COVID‐19 lockdown against that experienced during post‐lockdown, which has not been previously studied. The analysis utilizes daily and monthly climate data from 1991 to 2022 obtained from the Langley Research Centre's official website. The net effective temperature (NET) and thermo‐hygrometric index (THI) were employed to assess heat stress in cities. The findings indicate a sudden increase in heat stress levels during the post‐lockdown period, particularly in cities like Lucknow, Chandigarh, Patna, Kolkata, Ahmadabad, Jodhpur, Guwahati, and Delhi. Moreover, there is a noticeable decline in the number of comfortable days for both THI and NET in certain cities, such as Delhi, Chandigarh, Bhopal, Ahmadabad, and Jodhpur, in 2021 and 2022. This analysis also reveals an overall rise in the number of torrid and very hot days, with significant increases recorded in 2022 compared to 2020. With a few exceptions, most cities show rising trends in THI and NET, causing Indian cities to experience more torrid and very hot months. This study clarifies the effect of the COVID‐19 lockdown on bioclimatic comfort and offers important guidance for future studies in this field.

Heat Island dynamics and heat stress implications on the population of El-Mansourah conurbation, Egypt: temporal and proposed solutions using MODIS imagery and ENVI-met simulation

In Egypt, El-Mansourah Conurbation (EMC) is the second largest urban complex after Cairo Conurbation. This study focuses on identifying seasonal trends in land surface temperature during the daytime/nighttime in both urban and rural areas (RA), as well as the corresponding urban heat island (UHI) intensity 2001 to 2021. A time series of the Moderate Resolution Imaging Spectroradiometer (Terra MODIS) images was analyzed using the statistical methods of Mann-Kendall test (MKT) and Theil-Sen estimator (TSE). The findings showed that the diurnal cooling in ranged from −0.66 to −0.58 °C (p < .01) across all seasons. In contrast, the nocturnal UHI exhibited a warming trend in all seasons (except for spring) ranging from 0.08 to 0.16 °C (p > .1). Calculations of the Temperature-Humidity Index showed a decline in the population comfort over time, especially in the hot months, while there was a noticeable amelioration in the cool ones. To explore potential mitigation strategies, the simulation capabilities of ENVI-met were utilized. Based on a simple scenario, the ambient temperature of Salah Salem Street (SST) decreased by more than 2 °C. One suggestion put forth by the research is to implement mitigation measures to address the adverse consequences that naturally arise from the unavoidable dynamics of urban areas.

Shift work duration and heatstroke risk among healthcare workers during hot summer months: A modelling study across 34 Chinese cities

Heat stress issues in healthcare workers (HCWs) have been widely recognized but no published guidelines have clearly specified healthy shift work hours and the time to experience heatstroke while performing healthcare tasks in outdoor settings. Using a rational biophysical model and hourly meteorological data collected during sixty hot summer months (June–August 2002–2021) in 34 major Chinese cities, this study determined healthy shift work hours and heatstroke risks in HCWs with three levels of body mass index (BMI = 18.0, 23.0, and 27.0 kg/m2) while performing healthcare tasks. Our simulation results found that HCWs should switch shifts every 2 h. HCWs with a higher BMI could see their shifts extended by 10–28 min. HCWs with 18.0 kg/m2 BMI should finish shifts 10–23 min earlier than their counterparts. Heatstroke can strike HCWs in 143 min. HCWs should not wear impermeable PPE suits outdoors for >2 h in cities other than Guiyang, Qingdao, Kunming, Xining, and Lhasa for safety reasons. To ensure 8 h of healthy labor, HCWs are advised to wear personal cooling systems with a cooling power of ≥194.8 W/m2 or to work in testing booths, where HVAC setpoint temperature for PPE-clad HCWs is 25.0 °C, with RH = 50–65 % and a fanning speed of 2.5 m/s.

Hygrothermal Performance of simple intensive Green Roofs with Different Irrigation Schemes

Urban mesoclimate is formed by a multitude of factors enhancing climate change characteristics like increasing temperature levels, reduced air moisture content, atmospheric pollution or extreme rain events. All of these factors could be attenuated by green roof structures. Unfortunately, this potential is not being tapped in current building practice. The majority of erected green roofs are built as extensive, i.e. non-irrigated, types. This results in a poor mesoclimatic impact as the water contents of these roof substrate layers are meagre, and vegetation layers are more or less inactive during the dry, hot summer months. Intensive green roofs, on the other hand, require higher load-bearing capacities and costs, both often not eligible for refurbishments. A promising approach is a combination of simple intensive green roof structures featuring a thin substrate layer with reduced irrigation techniques, especially under the usage of grey water. The hygrothermal performance of these structures in comparison between different irrigation schemes and solar radiation levels is shown in this article. Measurements were performed over a period of about two years. Hygrothermal performance shows the importance of an optimised relationship between irrigation scheme, substrate type and thickness in order to achieve a sufficient evapotranspiration and temperature balancing effect.