Temperature Index Research Articles

Tree planting as a health promotion strategy on cycle paths in a municipality with unfavorable weather conditions for active transport

Improving conditions and encouraging active mobility has become a necessity in the current parameters of urbanization in Brazil. Using active transport, through cycling, provides a sustainable characteristic to the urban environment, integrating environmental, social and economic improvements. The present study aims to analyze the influence of afforestation on cycling structures’ comfort condition in a Brazilian municipality in a region with extreme climate conditions: high temperatures and humidity unfavorable to active transport. Temperature and relative humidity data were collected using an HTR-157 thermo-hygrometer in 7 urban cycling structures in the municipality of Sinop, State of Mato Grosso, Brazil, from March to July 2020. Temperature and humidity were used to determine the Temperature and Humidity Index (THI). The analysis using a dendrogram, carried out using the hierarchical grouping method, for the tree-lined and non-tree-lined cycle paths, showed that cycle path 7, the only one with the presence of continuous and contiguous trees on both sides of the road, showed different behavior from all the others, with more favorable temperature and relative humidity indicators for the entire analyzed period (dry and rainy). It is concluded that afforestation constitutes an important strategy for promoting health in the urban environment, providing better thermal comfort and environmental quality conditions, especially when there are low values of relative air humidity, positively supporting aspects related to afforestation such as aesthetics, safety and microclimate.

Multi-Temporal and Time-Lag Responses of Terrestrial Net Ecosystem Productivity to Extreme Climate from 1981 to 2019 in China

The escalating frequency and severity of extreme climate greatly impact the carbon dynamics of terrestrial ecosystems worldwide. To understand the multi-temporal response of net ecosystem productivity (NEP) to extreme climate, we investigated 11 temperature and precipitation extreme indices across different vegetation types in China. From 1981 to 2019, the results showed that NEP in China increased at a rate of 0.64 g·m−2·a−2. Extreme climate demonstrated a significant warming trend and a non-significant moistening trend; specifically, maximum daily minimum temperature (TNx) exhibited a significant increase at a rate of 0.34 °C/10 a, while maximum 5-day precipitation (Rx5day) showed an insignificant increase at a rate of 1.78 mm/10 a. NEP was significantly impacted by extreme temperature at the annual, seasonal, and monthly scales, but moderately impacted by extreme precipitation. Specifically, extreme temperature had the most significant effect on grassland, with minimal influence on cropland. In contrast, extreme precipitation had the most significant effect on forest, with minimal impact on cropland. Moreover, the lagged time for extreme precipitation was longer than that for extreme temperature. Extreme precipitation exhibited a corresponding lagged time of at least 2 months (p < 0.01), while extreme temperature exhibited a lagged time of at least 1 month (p < 0.01). The maximum lag time observed was 4 months (p < 0.01). Our findings provide valuable insights into the multi-temporal response of NEP to extreme climate in China and inform sustainable development practices in the region.

Long-term forecasting methods of dates of ice break-up and disappearance at the Dnipro Cascade Reservoirs by teleconnection indicators

Long-term forecasting of the ice regime at the Dnipro Cascade Reservoirs is very important, first of all, for the operation of hydroelectric power stations. In addition, such forecasts also ensure the work of other sectors of the economy, namely shipping, fisheries, municipal engineering, etc. At present, the Department for hydrological forecasting of the Ukrainian Hydrometeorological Center uses techniques developedin the middle and in thesecond half of the 20th century to compile long-term forecasts and advices about the ice regimeof water bodies of Ukraine. These techniqueswere developed only for rivers;for reservoirs,they are currently lacking.
 The main objective of our research is to develop methods for long-term forecasting of ice break-up and disappearance at the Dnipro Cascade Reservoirs by teleconnection indicators. The research was based on the recordsfor 35 water gauges located on 6 reservoirs of the Dnipro Cascade, including the destroyed Kakhovka reservoir. The dates of the ice break-up and disappearance were used for the period from the beginning of observations at each water gauge to 2020. Moreover, the teleconnection indicators were used, namely 34 atmospheric indices, sea surface temperature indices, teleconnection indices and patterns determined by the National Weather Service (NWS) of the National Oceanic and Atmospheric Administration of United States of America (NOAA USA).
 Methods of the long-term forecasting of the ice break-up and disappearance at the reservoirs of the Dnipro Cascade have been developed by searching for the best correlation or regression relationship between dates and teleconnection indicators. The probable of accepted errorsof the developed methods are in the range of 62—71 %, which corresponds to satisfactory method quality that makes it possible to recommend them for use.

Investigation of Temporal Trends and Spatial Patterns of Extreme Temperatures and Their Relationship to Climate Circulation Indices in Tanzania

This paper examined the spatial and temporal patterns of selected temperature extreme indices using the Mann-Kendall method (MK), the standard t-test, and the Pearson correlation analysis method. The relationship between extreme temperature events and climate circulation indices was analysed in Tanzania between 1983 and 2016 using data from 1961 to 2018. The results uncover a rise in the frequency and intensity of balmy days and nights across Tanzania. It suggests a significant increase in trends and the frequency of mild temperature index days and warm nights. It also indicates an increase in the trends for warm temperature indices (hottest days (TXx), coldest days (TNx), warm days (TX90p), tropical night (TR20), and Warm Spell Duration Indicator (WSDI); and a decrease in cold temperature indices (cold days (TX10p), cold nights (TN10p), cold days (TXn), and Cold Spell Duration Indicator (CSDI); which imply that the lower temperature was gradually decreasing more than in the past. The results further suggest that warm days and nights are significantly correlated with the Tropical Northern Atlantic Index (TNA), the Interdecadal Pacific Oscillation (IPO), the Atlantic Multidecadal Oscillation (AMO), and the El Nino-Southern Oscillation (ENSO). The circulation indices, which were found to be substantially associated with temperature extreme indices, can aid in forecasting, and may potentially serve as a foundation for future studies, particularly in the dynamics and physical mechanisms related to temperature extremes. The results presented in this paper are also vital for developing proper mitigation and adaptation measures to reduce future risks associated with extremely high-temperature events.

Thermal characterization and ventilation assessment of a battery-caged laying hen housing in the humid tropic climate.

The indoor climate to which livestock are exposed is a critical factor influencing their performance and productivity. Elevated air temperature and relative humidity could result in heat stress for laying hens. This situation results in severe adverse effects such as weight loss and mortality. Egg fertility and hatchability are also impacted. Consequently, a study was carried out in a naturally ventilated battery-caged laying hen house to measure climatic variables (air temperature, relative humidity and air velocity). The degree of heat stress was assessed using the temperature-humidity index (THI), and the index of temperature and air velocity (ITV) was also evaluated. According to the results obtained, birds reared within the study building would spend most of their productive life under stressful thermal conditions, which could significantly hamper their performance. The air velocity was below 1.0 ms-1 for most of the internal part of the housing, meaning natural air movement at the location was insufficient to provide a suitable environment for the birds. A high THI was recorded for nearly the entire study period. This high THI could indicate high relative humidity about air temperature. The observed ITV values (ITV > 25) suggest that birds throughout the building could be perpetually uncomfortable. The thermal and velocity profile within the structure could further be assessed numerically using computational fluid dynamics. This would enable engineers to make modifications to improve living conditions within the building.

Effects of PEMFC cooling channel insulation coating on heat transfer and electrical discharge characteristics of nanofluid coolants

Nanofluids have high thermal conductivity and electrical conductivity, and there is a problem of electrical discharge when used as a coolant in proton exchange membrane fuel cell (PEMFC). In this study, the compact Al2O3 insulating coating was prepared by supersonic plasma spray processing technology and evenly coated in the cooling channel. The electrical discharge effect and heat transfer enhancement ability of three coolants, namely deionized water, Al2O3 nanofluid and graphene nanofluid, were studied when applied in the electrically active atmosphere of PEMFC. The results show that, the graphene nanofluid has the best heat transfer performance before insulation coating integration, but the dispersion of solid nanoparticles in the base fluid leads to a higher pressure drop, with an increase of 6.7%. When the voltage is 200 V, the leakage current of Al2O3 nanofluid and graphene nanofluid is up to 16 mA and 33 mA respectively. After insulation coating integration, the index of uniform temperature (IUT) and maximum temperature of graphene nanofluids further decrease, while the pressure drop increases by 7.0%. The leakage current of all three coolants at different voltages and Re numbers decrease to 0, indicating a significant improvement in the insulation performance of PEMFC cooling channel. In addition, dimensionless evaluation parameter ε for the applicability of heat transfer fluids were proposed from the perspectives of work and energy. Within the pump power range of 0.0065 W ∼ 0.0325 W, the ε of graphene nanofluids with insulating coating is always lower than Al2O3 nanofluid. At the pump power of 0.014 W, the ε of graphene nanofluids with insulating coating is 0.76, which has the best coolant applicability when applied in the electrically active atmosphere of PEMFC.

Identifying heat thresholds for South Africa towards the development of a heat-health warning system.

Exposure to heatwaves may result in adverse human health impacts. Heat alerts in South Africa are currently based on defined temperature-fixed threshold values for large towns and cities. However, heat-health warning systems (HHWS) should incorporate metrics that have been shown to be effective predictors of negative heat-related health outcomes. This study contributes to the development of a HHWS for South Africa that can potentially minimize heat-related mortality. Distributed lag nonlinear models (DLNM) were used to assess the association between maximum and minimum temperature and diurnal temperature range (DTR) and population-adjusted mortality during summer months, and the effects were presented as incidence rate ratios (IRR). District-level thresholds for the best predictor from these three metrics were estimated with threshold regression. The mortality dataset contained records of daily registered deaths (n = 8,476,532) from 1997 to 2013 and data for the temperature indices were for the same period. Maximum temperature appeared to be the most statistically significant predictor of all-cause mortality with strong associations observed in 40 out of 52 districts. Maximum temperature was associated with increased risk of mortality in all but three of the districts. Our results also found that heat-related mortality was influenced by regional climate because the spatial distribution of the thresholds varied according to the climate zones across the country. On average, districts located in the hot, arid interior provinces of the Northern Cape and North West experienced some of the highest thresholds compared to districts located in temperate interior or coastal provinces. As the effects of climate change become more significant, population exposure to heat is increasing. Therefore, evidence-based HHWS are required to reduce heat-related mortality and morbidity. The exceedance of the maximum temperature thresholds provided in this study could be used to issue heat alerts as part of effective heat health action plans.

Laboratory short-term aging of crumb rubber modified asphalt: RTFOT temperature optimization and performance investigation

Improper disposal of substantial scrap tires can result in significant environmental issues, such as air pollution, water resources, and soil contamination. The scrap tires can be turned into valuable materials by preparing tire rubber powder into Crumb rubber modified asphalt (CRMA). This method can effectively reduce environmental pollution and achieve the concept of energy conservation, environmental protection, and low-carbon. However, during the production process of CRMA mixtures, the elevated construction temperature may induce more severe short-term aging of the mixtures. The standard laboratory short-term aging scheme of asphalt binders, the Rolling Thin Film Oven Test (RTFOT), cannot simulate the short-term aging of CRMA due to the increase in construction temperature. Besides, the determination methods and indices of RTFOT aging temperature are still unclear and inconsistent. In this study, three CRMA binders were treated by RTFOT with five temperatures, and the short-term oven aging (STOA) protocol was conducted on CRMA mixtures with three types of gradations. Firstly, the chemical and rheological performance of CRMA binders and mixtures were investigated by conducting Gel permeation chromatography (GPC), Fourier transformation infrared spectroscopy (FTIR), Dynamic shear rheology (DSR) tests, and Bending beam rheometer (BBR) test. Then, the equivalent aging temperatures were determined to optimize RTFOT temperatures by comparing the chemical indicators of binders and mixtures. Finally, the correlations of chemical and rheological indices were established, and the rheological properties of aged asphalt in mixtures were predicted. The analysis results indicate that suitable RTFOT temperature is not only related to the technical routes and viscosity of CRMA binders, but also relevant to the mixture gradations. Binders with higher viscosity need elevated RTFOT temperatures from 173 °C to 193 °C, especially simulating short-term aging of mixtures with higher air voids. The swelling and degradation of crumb rubber contribute to the enhancement of the anti-aging performance. The aging index (AI) can reflect the anti-aging performance of CRMA binders, and the variation of AI can validate the rationality of the optimized RTFOT temperatures.

Effects of Climatic Conditions and Supplementation with Palm Cake on the Thermoregulation of Crossbred Buffaloes Raised in a Rotational Grazing System and with Natural Shade in Humid Tropical Regions.

In ruminants, diet composition has a positive correlation with heat production, which can influence thermoregulation, energy expenditure and, consequently, animal performance. The objective of this work was to evaluate the effects of climatic conditions and supplementation based on palm kernel cake, on the thermoregulation of crossbred buffaloes in the eastern Amazon. The research was carried out at Embrapa Amazônia Oriental (01°26' S and 48°24' W), Belém, Pará, and lasted 12 months (representing the entire year). Twenty-four buffaloes, females, with initial age and an average weight of 54 ± 7 months and 503.1 ± 23 kg, respectively, non-pregnant, non-lactating and clinically healthy were used, divided into four treatments based on the supplementation content of the palm cake (%DM) in relation to their body weight (%): 0, 0.25, 0.50 and 1.0. The animals were kept in paddocks with Brachiaria brizantha (cv. Marandu), in a rotating system, with water to drink and mineral salt ad libitum. Equipment was installed to record environmental data (temperature and relative humidity, dew point temperature, wet bulb and black globe) and physiological data: rectal temperature (RT); respiratory rate (RR); and body surface temperature (BST), recorded twice a day, always in the morning (6:00 a.m. to 7:00 a.m.) and afternoon (12:00 p.m. to 1:00 p.m.) shifts, and were used to calculate the Globe Temperature and Humidity Index (GTHI). Supplementation did not influence the physiological variables of thermoregulation (p > 0.05). However, there were differences in the GTHI between the shifts, with higher means in the afternoon shift, especially in the less rainy period of the year, where the GTHI reached 92.06 ± 2.74 (p < 0.05). In all periods of the year, the mean values of RT, RR and BST were higher in the afternoon shift (p > 0.05). The respiratory rate (RR) is associated with the annual seasonality of the thermal waters, with higher averages in the afternoons of the rainy season. The positive correlation for rectal temperature, respiratory rate and body surface temperature indicated that buffaloes respond to thermal elevations in the atmosphere (afternoon period) and, consequently, reflect on the GTHI. Supplementation does not influence thermoregulation; the changes observed occurred in response to the region's thermal and rainfall conditions (mainly in the afternoon shift), with higher GTHI values.

Comparative aspects on the epoxidation of soybean oil and high oleic soybean oil

AbstractSoybean oil (SO) epoxidation is an extensively studied method to generate a sustainable plasticizer for polyvinyl chloride (PVC). Standard soybean oil is composed of triglycerides whose fatty acids are primarily unsaturated linoleic, oleic, and linolenic acids. High oleic soybean oil (HOSO) is collected from a soybean variety higher in oleic acid than other acids. The present study focused on a preliminary comparison of the epoxidation reaction behavior between SO and HOSO, conducted isoperibolically and without catalysts. The experimental data were modeled by a kinetic model. Considerable differences in the temperature and oxirane index profiles suggest that the epoxidation of HOSO tends to be faster and with a more intense heat release rate than the epoxidation of SO, which was confirmed by the results of estimated kinetic constants. The data collected and shared herein suggest that a first epoxy group generated may cause steric hindrance to slow the epoxidation in the second and third double bonds of the oil.

RGBW LED mixing temperature compensation method with high output consistency

This paper proposes a temperature compensation method for RGBW LED mixing based on fast non-dominated sorting genetic algorithm(NSGA-II). The proposed method can achieve compensation for temperature-induced changes in LED correlated color temperature (CCT), color fidelity (Rf) and color gamut index (Rg) by predicting the spectral power distribution (SPD) at different temperatures. The SPD-temperature model of the RGBW LED light source is established by measuring the spectral power distribution of LEDs at different temperatures. Based on the established model, NSGA-II is used to compensate the mixing temperature of the RGBW LED light source according to the spectral superposition theorem. The experimental results show that the fit of the established temperature-spectral model is R2 > 0.98, and the deviation of the compensated mixing results from the initial state of the light source is less than 10 K in CCT; the deviation value of Rf is less than 4 % in the range of 2000 K-7000 K, and less than 2.15 % in the range of 3000 K-7000 K; and the deviation value of Rg in the range of 2000 K-7000 K is less than 4.46 %.

A systematic review of genotype-by-climate interaction studies in cattle, pigs, and chicken

The genetic progress achieved by animal breeding programs may be affected by genotype-by-climate interactions (GxC). This systematic literature review assesses the scientific evidence for GxC on multiple traits of cattle, pigs, and poultry. Two search engines (Scopus, Web of Science) were queried for original peer-reviewed scientific (English full-text) studies. We included (1) observational studies and designed experiments considering dairy or beef cattle, swine, chicken or turkeys, where (2) at least one production, fertility, or health trait was tested for GxC, (3) the existence of GxC was tested directly based on temperature, relative humidity, or climatic indices for heat or cold stress, and (4) genetic effects within a breed or line were investigated. The search resulted in 46 eligible studies, with a (low) risk that the requirement of full-text English studies may have resulted in some work not included in this review. Our review shows an increase in GxC studies from 2015 onwards. Cattle was the most studied species (n = 36; 78.3%), whereas eligible studies on turkeys were lacking. Climatic parameters used in the studies ranged from well-known parameters (e.g., temperature, temperature-humidity index) to more complex indices combining temperature, relative humidity, wind speed and solar radiation. All observational studies (n = 40; 87.0%) used weather station data. In total, 75 traits were studied, which were predominantly production traits regardless of species. Studies on fertility and health traits have been emerging from 2010 onwards, but their numbers still lag far behind those for production traits. Genotype-by-climate interaction was confirmed in 54.0% of the study outcomes. This systematic review shows that little is known about the role of GxC in health and fertility traits in cattle, and for all traits in pigs and poultry in general. As current evidence shows that genotype-by-climate interaction is common across species and traits, we suggest to collect detailed climatic data and use them to assess the presence of GxC in indoor and outdoor production systems, as well.

Heterogeneity in habitat and microclimate delay butterfly community tracking of climate change over an elevation gradient

Gradients in community diversity and composition rarely track rates of warming, prompting efforts to understand the factors causing non-equilibrium responses to climatic change and their implications for conservation. Here, we test the roles of fine-resolution habitat heterogeneity and microclimate in delaying butterfly community responses to warming over a mountain elevation gradient. We assess species diversity and Community Temperature Index (CTI) in 2004–2005 and 2017 across 120 transect sites in the Sierra de Guadarrama (Spain), modelling temperatures based on topography, and vegetation structure based on LiDAR. A humped elevation gradient in species diversity was maintained over time. However, diversity in the later period was more positively related to vegetation heterogeneity, and sites with reduced rates of warming and greater forest cover maintained or increased their diversity. Site CTI declines with increasing elevation, showing little evidence of systematic change over the gradient between periods, although CTI increased most in locations with the greatest rates of spring microclimatic warming. Our results show that delays in community tracking of climatic conditions could result partly from positive effects of habitat and topographic heterogeneity providing microclimatic buffering against warming to existing communities; although barriers to colonization could also delay diversity increases and community thermophilization at high elevations. We suggest that protecting and managing complex habitats with high community diversity, and identifying localized microclimates that buffer populations against negative effects of warming, are more immediate conservation priorities over elevation gradients than efforts to ensure that communities track prevailing rates of warming.

Evaluation of statistical downscaling techniques and projection of climate extremes in central Texas, USA

This study evaluates statistical downscaling techniques using different metrics and compares climate change signals and extreme precipitation and temperature changes under future climate change scenarios in the Bosque watershed, North-Central Texas. The study utilizes observed gridded Daymet data to assess the effectiveness of statistical downscaling techniques. It involves comparing the mean, the 90th percentile, 10th percentile, wet day frequency, and Cumulative Distribution Function (CDF) of climate model simulations before and after downscaling and the Daymet data during the historical period (1981–2005). Furthermore, the study analyzes changes in climate change signals, extreme precipitation, and temperature values under both near-future (2031–2060) and far-future (2070–2099) climate scenarios. The Ratio Delta method (DeltaSD) and Equi-Distant Quantile Mapping (EDQM) statistical downscaling techniques adjust the mean annual, the wet days frequency, the 90th and 10th percentiles, and the CDF of Global Climate Models (GCMs) simulations of historical precipitation and temperature. The downscaling techniques influenced the climate change signal and changes in extreme values in the future climate. When examining future climate projections produced using the DeltaSD method, we observe a more pronounced reduction in precipitation, while simulations generated through EDQM exhibit a higher frequency of heavy precipitation events (R10mm, R20mm) and consecutive dry days (CDD). It's worth noting that the uncertainties associated with the statistical downscaling techniques are relatively small and not statistically significant (≤0.05). In contrast, substantial and significant uncertainties arise from the choice of emission scenarios and the selection of driving GCMs. Across most climate change scenarios, there is a consistent trend towards increased temperatures and extreme temperature indices. The trend of extreme temperature indices shows variation following the choice of emission scenarios where a significant change in temperature extremes was detected under the RCP8.5 emission scenario.

Geographical verification of Pleuropterus multiflorus thunb. by functional compounds, stable isotope ratios, and multielement combined with machine learning methods

The dry roots of Pleuropterus multiflorus Thunb. (PM) have been traditionally utilized as functional foods and medicines China and various Asian countries. They are extensively cultivated in multiple provinces in China, with variations in prices and qualities. This study aims to investigate the regional characteristics of PM by 4 stable isotope ratios, 40 multielement and 16 functional compounds contents, using a total of 357 samples from 8 different geographical origins. Machine learning methods were developed to authenticating the geographical origins of PM, yielding the accuracy range from 94.44 % to 100 % in the test set. Notably, the protected designation of origin, Deqing PM, exhibited a high accuracy of 100 % in most models, A total of 30 significant prediction variables, encompassing 16 functional compounds, δ2H, 12 rare earth elements, and Cu, were identified. Additionally, the study identified altitude, high temperature, and dry or moisture index as the primary influenced environmental factors.

Setting up the ENVI-met digital tool to evaluate climatic conditions at an urban scale: a case study of Djelfa, Algeria

Urbanization has radically transformed natural landscapes, giving rise to complex urban environments worldwide. This transformation poses unique challenges in terms of climatic conditions. We emphasize the crucial importance of understanding urban microclimates shaped by geographical, architectural and human factors, requiring meticulous management for sustainable urban planning. These multifaceted factors interact to produce spatial variations in solar exposure, temperature and wind conditions, leading to distinct microclimatic pockets within cities. This underlines the imperative need for sustainable urban planning and design that takes account of their impact. Our field survey is located in Djelfa, Algeria, featuring a semi-arid to arid climate with continental influences. This article presents a methodology involving a detailed morphological analysis of the urban fabric, focusing on its structure, vegetation cover and spatial characteristics. It describes the use of ENVI-met, a powerful microclimate simulation tool offering a complete three-dimensional modeling system that integrates various urban elements, including buildings, streets and green spaces. Our spatial considerations guarantee model accuracy, with a rigorous geometry validation process maintaining model fidelity. The tool produces invaluable output data, including air temperature, relative humidity and thermal comfort indices. This paper emphasizes on the application of the model in Djelfa, Algeria, highlighting its potential in evaluating thermal condition in urban environments. The results of our study highlight significant temperature and humidity disparities between urbanized and green areas in the survey area, with temperature differences of up to 6&amp;deg;C during the day. Urbanized areas consistently have higher air temperatures and lower humidity levels, particularly during the day. Conversely, green spaces, including gardens and tree-lined areas, exhibit lower temperatures and higher humidity levels, offering valuable respite from heat stress. The use of the Physiological Equivalent Temperature (PET) index allows us to assess thermal comfort, revealing variations in heat stress levels across the urban landscape. This research highlights the crucial importance of integrating green infrastructure into urban planning to improve thermal comfort and livability in cities. Furthermore, our study reveals the value of advanced tools like ENVI-met in understanding urban microclimates and provides valuable information for sustainable urban development and climate adaptation strategies.

Temperature Index of Antiviral Drugs Used to Combat Viral Diseases

Temperature Index of Antiviral Drugs Used to Combat Viral Diseases

Effects of different heat transfer fluids on thermal distribution and electrochemical performance of PEMFC with a non-isothermal multiphase model

Proton exchange membrane fuel cell (PEMFC) with long service life, low parasitic loss and high-power density is one of the main technologies to achieve zero emission of automobiles. Efficient coolant is crucial for reducing the volume and complexity of thermal management system. In this study, the 3-D non-isothermal multiphase PEMFC model coupled with parallel cooling channels was established by using CFD simulation platform, and then the effects of four heat transfer fluids, namely deionized water, Syltherm800 heat transfer oil, 1.0 vol% Al2O3 nanofluid and K0.78Na0.22 liquid metal, on the heat and mass transfer characteristics and electrochemical performance of PEMFC were investigated. The results show that with the Re number increases, the PEMFC maximum temperature, temperature difference and index of uniform temperature (IUT) of water, nanofluid and liquid metal cooling modes decreased significantly than those of heat transfer oil cooling mode. While the heat transfer oil cooling mode has the lowest IUT and the highest peak temperature because of more oxygen involved in the side reaction. The relatively low temperature in PEMFC with liquid metal cooling mode will increase the water content of the membrane and improve the proton conductivity. In addition, at Tin = 345 K and Re = 900 condition, the net power of PEMFC with liquid metal cooling mode is up to 128.23 W, which is 1.62 % higher than that of water cooling mode. This confirms that the application of liquid metal coolant in thermal management system can effectively improve the performance of PEMFC.

Solar PV technologies selection for the design of photovoltaic installations in Mexico based on the analysis of meteorological satellite data from the region

Mexico’s expansive territory spans diverse climatic conditions, which directly influences the selection of commercial photovoltaic technologies. This study utilizes solar irradiance, temperature, and cloud index data (derived from satellite sources) to generate a suitability map for commercial solar panel technologies through the Analytical Hierarchy Process-Geographical Information Systems methodology. The map illustrates that chalcopyrites and cadmium telluride emerge as the most suitable technologies in 47.12% of the national territory. Following closely behind is amorphous silicon, covering 30.45%, while monocrystalline and polycrystalline silicon account for 22.43%. The primary objective of this paper is to guide the proper selection of solar panel technology types that align optimally with Mexico’s climatic conditions. This strategic approach aims to strengthen the planning and viability of photovoltaic solar energy projects nationwide.

Evaluation of moth community changes and northward shifts in response to climate warming in Korea using both local and global occurrences

Although climate warming arguably induces changes in species distribution, thereby causing poleward shifts in various taxa, comprehensive research on the response of moths to climate warming is lacking. This study compared the distribution of macro-moths between historical (1978–2002) and recent (2011–2016) periods in South Korea using the macro-moth data collected at 18 survey sites to elucidate the changes in community composition. We used the community temperature index (CTI) to quantify the effect of temperature change on moth community changes. The CTI represents the average value of the species temperature index (STI; mid-value of thermal range) calculated using our local observations and global occurrences reported in the online database of the Global Biodiversity Information Facility. Our analysis revealed no significant difference in species richness between historical and recent surveys. However, some taxa, such as Uraniidae, Nolidae, Sphingidae, and Lasiocampidae, exhibited high turnover rates, while the number of sphingid moths with large body sizes greatly decreased. The temperature changes at the survey sites became pronounced with an increase in the survey interval (year) between historical and recent surveys (temperature increase = 0.0465 ℃ /year), while the CTI change exhibited a weak signal for northward shift of moth species. The CTI using the local data indicated 0.09 km/year of northward shift of moths, which is considerably slower than the northward shift (9.6 km/year) of the isothermal bands. However, the CTI using global occurrence data, expected to improve the estimation of species thermal niches, did not show any sign of northward shift. When observed, the northward shifts of moths were primarily identified in the cold-adapted species with low STI values, suggesting that cold-adapted species are more sensitive and vulnerable to climate warming than warm-adapted species. These results indicate that the current distribution changes of species were uneven, and the species adapted to cold regions are the ones primarily responding to the temperature increase by migrating northward and to high elevations.