Winter Environment Research Articles

Evaluating climate change impacts on ecosystem resources through the lens of climate analogs

As disturbances continue to increase in magnitude and severity under climate change, there is an urgency to develop climate-informed management solutions to increase resilience and help sustain the supply of ecosystem services over the long term. Towards this goal, we used climate analog modeling combined with logic-based conditions assessments to quantify the future resource stability (FRS) under mid-century climate. Analog models were developed for nine climate projections for 1 km cells across California. For each model, resource conditions were assessed at each focal cell in comparison to the top 100 climate analog locations using fuzzy logic. Model outputs provided a measure of support for the proposition that a given resource would be stable under future climate change. Raster outputs for six ecosystem resources exhibited a high degree of spatial variability in FRS that was largely driven by biophysical gradients across the State, and cross-correlation among resources suggested similarities in resource responses to climate change. Overall, about one-third of the State exhibited low stability indicating a lack of resilience and potential for resource losses over time. Areas most vulnerable to climate change occurred at lower elevations and/or in warmer winter and summer environments, whereas high stability occurred at higher elevation, or at mid-elevations with warmer summers and cooler winters. The modeling approach offered a replicable methodology to assess future resource stability across large regions and for multiple, diverse resources. Model outputs can be readily integrated into decision support systems to guide strategic management investments.

The effects of genotype-by-environment interactions on body condition score across three winter supplemental feed environments in a composite beef cattle breed in Montana.

Cattle operations in the Northern Great Plains region of the United States face extreme cold weather conditions and require nutritional supplementation over the winter season in order for animals to maintain body condition. In cow-calf operations, body condition scores (BCS) measured at calving and breeding have been shown to be associated with several economically important health and fertility traits, so maintenance of BCS is both an animal welfare and economic concern. A low-to-medium heritability has been found for BCS when measured across various production stages, indicating a large environmental influence but sufficient genetic basis for selection. The present study evaluated BCS measured prior to calving (late winter) and breeding (early summer) under three winter supplementation environments in a multitrait linear mixed model. Traits were discretized by winter supplementation and genetic correlations between environments were considered a reflection of evidence for genotype-by-environment interactions between BCS and diet. Winter supplementation treatments were fed October through April and varied by range access and protein content: 1) feedlot environment with approximately 15% crude protein (CP) corn/silage diet, 2) native rangeland access with 1.8kg of an 18% CP pellet supplement, and 3) native rangeland access with a self-fed 50% CP and mineral supplement. A total of 2,988 and 2,353 records were collected across multiple parities on 1,010 and 800 individuals for prebreeding and precalving BCS, respectively. Heifers and cows came from a composite beef cattle breed developed and maintained by the USDA Fort Keogh Livestock and Range Research Laboratory near Miles City, Montana. Genetic correlations between treatments 1 and 2, 1 and 3, and 2 and 3 were 0.98, 0.78, and 0.65 and 1.00, 0.98, and 0.99 for precalving and prebreeding BCS, respectively. This provides moderate evidence of genotype-by-environment interactions for precalving BCS under treatment 3 relative to treatments 1 and 2, but no evidence for genotype-by-environment interactions for prebreeding BCS. Treatment 3 differed substantially in CP content relative to treatments 1 and 2, indicating that some animals differ in their ability to maintain BCS up to spring calving across a protein gradient. These results indicate the potential for selection of animals with increased resilience under cold weather conditions and high protein, restricted energy diets to maintain BCS.

Multiomics analyses reveal the mechanisms of the responses of subalpine treeline trees to phenology and winter low-temperature stress.

Withstanding extreme cold stress is a prerequisite for alpine treeline trees to persist and survive. However, the underlying mechanism by which treeline trees sense phenological changes and survive hard winters has not been fully elucidated. Here, we investigated the physiology, transcriptome, and metabolome of the subalpine treeline species Larix chinensis to identify the molecular mechanism of phenological and cold resistance. Calcium and antioxidant enzyme activities (e.g., superoxide dismutase and glutathione peroxidase) are essential for coping with winter cold stress in L. chinensis. Transcriptome analysis revealed that circadian rhythm and phytohormone signalling transduction played important roles in regulating L. chinensis phenological changes and cold stress responses. The variations in the transcriptome identified were accompanied by the specific accumulation of flavones, flavonols, and monosaccharides. The flavonoid biosynthesis and phenylpropanoid biosynthesis pathways played important roles in the adaptation of L. chinensis to the extreme winter environment, and flavone and flavonol biosynthesis was an important pathway involved in bud burst. In addition, temperature and photoperiod had synergistic influences on the formation and release of bud dormancy. Thus, our findings provided new insights into the mechanism of subalpine treeline formation.

Evaluation of Compressive Strength of UHPC Cured in A Winter Low-temperature

Deteriorating concrete quality is a typical problem reported in a low-temperature environment in winter. Therefore, efforts to evaluate and secure the quality of concrete are always carried out. In this study, the researchers primarily focused on developing curing methods and improving the quality of mixing materials, including chemical admixture, to secure compressive strength of concrete. The study investigated the compressive strength of concrete according to its age and observed that the compressive strength increases under the experimental conditions without any additional protection measures for the winter season. The compressive strength of the cured concrete was measured at 0 and -15 ℃ for 100 MPa Ultra-high-performance concrete (UHPC). Additionally, the property of compressive strength was compared with that of UHPC, which suffered damage due to the cold, went through a certain recovery period at room temperature. Consequently, it was confirmed that UHPC, damaged from the cold weather, achieved the specific compressive strength after 84 days. The findings from this study can enhance further understanding of the characteristics of UHPC in winter environments and contribute to establishing a construction plan for withstanding the winter seasons.

Highly Antifreezing Thermogalvanic Hydrogels for Human Heat Harvesting in Ultralow Temperature Environments.

Thermogalvanic hydrogels have been quickly developed and are widely used in thermal energy harvesting. However, the freezing behaviors of thermogalvanic hydrogels at subzero temperatures greatly limit their practical applications. Herein, we design an antifreezing thermogalvanic hydrogel based on [Fe(CN)6]3-/4- ions for thermoelectric power generation in ultralow temperature environments. The antifreezing thermogalvanic hydrogels show excellent flexibility at -80 °C owing to the hydrogen bonding between ethylene glycol and water molecules. Even after 500 cyclic tensile strains, the thermogalvanic hydrogels can still maintain excellent mechanical stability, and the Seebeck coefficient is as high as 1.43 mV/K, corresponding to a large retention rate of ∼95%. Moreover, we demonstrate a wearable thermoelectric shoe based on antifreezing thermogalvanic hydrogels for harvesting human thermal energy in a simulated winter environment of -30 °C, and the electricity can drive a green LED. This work provides important guidance for the design and optimization of antifreezing thermogalvanic hydrogels.

Field Study to Compare and Evaluate Summer Thermal Comfort of School Buildings with Different Moderate Thermal Mass in Their Building Elements

Previous studies show that moderate thermal mass in school building elements can positively impact the winter indoor thermal environment in a temperate climate with mild, humid winters. Based on a field study, this research contributes new physical data of the summer indoor thermal environment of Auckland school buildings with different designs of moderate thermal mass in their building elements to add to the previous winter field-study data and demonstrates that a school building with moderate thermal mass is adequate in a temperate climate with mild, humid winters and warm, dry summers. This field study compared and evaluated the summer indoor thermal environment of classrooms with different moderate thermal mass in their building elements during the summer school term and the summer school holidays. This study found that a classroom with thermal mass in its building elements has 19% to 21% more time in summer than a classroom without any thermal mass in its building elements when indoor air temperatures are within the thermal comfort zone, which was solely impacted by the building’s thermal performance. This study established a suitable research method to analyse the field-study data and identify the differences in the indoor thermal environments of the school buildings with different designs of moderate thermal mass in their building elements.

Unclear relationships in interference competition among three sympatric medium-sized carnivores in a heavy snowy environment

Abstract Interference competition, a category of interspecific competition, is a critical aspect of understanding the dynamics of carnivore communities, as it can result in a decline in the health and reduced opportunity for resource acquisition of one or both competing species. Heavy snowfall environments during winter are expected to exacerbate interference competition due to decreased food resources and limited foraging opportunities caused by snow cover. However, knowledge on interference competition in such environments is limited. Using camera traps with baits, we evaluated the interference competition among three sympatric medium-sized carnivores, red foxes, raccoon dogs, and Japanese martens, within a heavy snowfall region of northeastern Japan. As in previous studies, we hypothesized that body weight would serve as a determining factor for superiority in winter snow environments. Diel activity patterns using the visitation time to baits did not reveal any clear differences. Nevertheless, the daytime occurrence frequency of Japanese martens during the snowfall season was higher than that of the other two species, indicating inferiority to the other species. The analysis of time intervals between species visiting baits revealed no clear superiority among the target species. These findings suggest that the interspecific relationships among medium-sized carnivores in winter snowy environments are complex and not easily determined.

Influence of lubricating oil circulation characteristics on the performance of electric vehicle heat pump system under low temperature conditions

Electric vehicles frequently employ heat pump systems for winter heating. In winter low-temperature environments, the viscosity of lubricating oil increases, forming an oil film as the refrigerant enters the heat exchanger, consequently impacting the heat transfer efficiency and overall performance of the heat pump system. This paper presents the design and implementation of an experimental heat pump system tailored for electric vehicles. The experimental setup incorporates a specialized device for lubricating oil sampling and an assessment methodology for evaluating heat pump functionality. Under a range of low-temperature conditions, the system underwent comprehensive testing, enabling a detailed analysis and synthesis of the flow characteristics and the influence of lubricating oil within both the heat pump system and the heat exchanger. The results reveal that the oil circulation rate is directly affected by the compressor oil charge, and maintaining the oil circulation rate within the range of 3 %–4 % results in a peak COP of the system. When the ambient temperature is 0 ℃ and the oil filling volume is 200 g, the oil circulation rate is 3.87 %, and the COP can reach 1.93. In addition, as the oil retention in the evaporator increases by 15.67 g, the COP value decreases by 21 %. Similarly, the increase in oil retention in the condenser from 2.43 g to 6.25 g resulted in a corresponding decrease in heat transfer capacity of 0.07 kW/K, leading to an overall deterioration of the system's performance.

A Survey of Ski Patrols in the United States Comparing Medical Direction, Patroller Training, and Patient Care.

Ski patrols are tasked with substantial challenges: distance from definitive care, complex extrications, and winter environments. Rules for US ski patrols stipulate that ≥1 persons be trained in basic first aid, but no further regulations regarding the specifics of provided medical care exist. This project investigated patroller training, patient care, and medical direction of US ski patrols through a survey of ski patrol directors and medical directors. Participants were contacted via email, phone, and personal contacts. After consultation with known ski patrol directors and medical directors for question guidance, 2 separate institutional review board-approved surveys were designed: 1 for ski patrol directors and 1 for ski patrol medical directors, containing 28 and 15 qualitative questions, respectively. The surveys were distributed with a link to the encrypted Qualtrics survey platform. After 2 reminders and 4 mo, results were downloaded from Qualtrics into an Excel spreadsheet. Twenty-two responses from patrol directors and 15 from medical directors were received. The response rate is unknown. Outdoor emergency care certification was the minimum medical training required by 77% of the study participants. Twenty-seven percent of surveyed patrols belonged to an emergency medical service agency. Fifty percent of 11 surveyed ski patrols had a medical director, 6 of whom were board certified in emergency medicine. All surveyed medical directors stated that they assisted with patroller education, and 93% assisted with protocol development. The surveys demonstrated variability in patroller training, protocols, and medical directorship. The authors questioned whether ski patrols would benefit from increased standardization of care and training, quality improvement programs, and medical directorship.

Effects of high-fiber food on gut microbiology and energy metabolism in Eothenomys miletus at different altitudes.

Intestinal microorganisms assist the host in digesting complex and difficultly decomposed foods; expand the host's dietary ecological niche. In order to investigate the effect of high-fiber food on intestinal microorganisms of Eothenomys miletus at different altitudes, exploring the regional differences of intestinal microorganisms and their roles in body mass regulation, we collected E. miletus from Dali (DL) and Xianggelila (XGLL), which were divided into control group, high-fiber group fed with high-fiber diet for 7 days, and refeeding group fed with standard diet for 14 days after high-fiber diet. Using 16S rRNA gene sequencing technology combined with physiological methods, we analyzed the gut microbial diversity, abundance, community structure and related physiological indicators of each group, and explored the effects of high-fiber foods and regions on the diversity, structure of gut microorganisms and physiological indicators. The results showed that high-fiber food affected the food intake and metabolic rate of E. miletus, which also showed regional differences. The intestinal microorganisms of E. miletus obtained energy through the enrichment of fiber degrading bacteria under the condition of high-fiber food, while producing short-chain fatty acids, which participated in processes such as energy metabolism or immune regulation. Moreover, it also affected the colonization of intestinal microorganisms. High-fiber food promoted the enrichment of probiotics in the intestinal microbiota of E. miletus, but pathogenic bacteria also appeared. Therefore, the changes in the composition and diversity of gut microbiota in E. miletus provided important guarantees for their adaptation to high fiber food environments in winter.

The Impact of Vegetation Canopy on the Outdoor Thermal Environment in Cold Winter and Spring

The current study investigated the impact of vegetation canopy on the outdoor thermal environment in cold winter and spring, a less-explored aspect of its climate effects. Firstly, we conducted on-site observations of meteorology parameters on a campus in a hot summer and cold winter region. Then the ENVI-met microclimate simulation model was utilized to simulate the air temperature, relative humidity, wind speed and direction, and solar radiation of typical winter and spring days. Furthermore, the PET index was calculated to evaluate the thermal conditions. Our findings revealed that during the daytime, the vegetation canopy raised air temperature and relative humidity, reduced wind speed, and mitigated solar radiation. Solar radiation emerged as the primary factor affecting thermal comfort in the cold winter and spring. The presence of deciduous broad-leaved vegetation notably reduced cold discomfort and improved thermal comfort in the cold winter and spring. Finally, we propose replacing evergreen broad-leaved vegetation with deciduous broad-leaved vegetation in hot summer and cold winter regions to ensure year-round thermal comfort, especially in the cold winter and spring.

The role of admixed CaO in a sulphoaluminate cement system under winter environments

Sulfoaluminate cement (CSA) is a low-carbon binder and can be regarded as an ideal cementitious material for winter construction and repair projects. However, the admixed CaO on the performance of CSA and its mechanism is still unclear, as well as the investigations and applications of CSA in negative temperature environments are very limited. Therefore, the impact of CaO on the setting time, compressive strength, cooling curve, and microscopic properties of CSA composite are systematically investigated. The experimental results reveal that the admixed CaO can significantly improve the compressive strength of CSA composite at negative temperatures (e.g., −5 °C, −10 °C, and −20 °C), and the admixed 2% CaO is the most effective in enhancing the compressive strength of CSA paste. At the beginning of hydration, CaO-modified CSA paste shows a significant exothermic peak, thus the freezing process of the liquid phase is retarded and the CSA can sustain hydration at −20 °C. Remarkably, the admixed 2% CaO can reduce the freezing point of the liquid phase of CSA paste to −7.2 °C, accordingly, decreasing the amount of freezable water and the risk of frost damage.

Effects of 36-hour recovery on marksmanship and hormone concentrations during strenuous winter military survival training

ObjectivesSurvival training can provide a unique setting for scientific examination of human stress responses and physical performance in a realistic operational military context. The aim of the present study was to observe effects of a 36-h recovery period on serum hormone concentrations, salivary cortisol, and marksmanship during 10-day winter military survival training in north of the Arctic Circle.Design and methodsSixty-eight male soldiers were randomly divided into two groups; EXP (n = 26) and CON (n = 42). While CON performed the whole exercise phase in the field, EXP had 36-h recovery period between days 6 and 8. Several hormones were measured during the study to investigate recovery.ResultsSubjective physical and mental demand as well as catabolic hormone levels increased and anabolic hormones decreased in CON (p < 0.05), whereas in EXP, recovery period attenuated negative effects of survival training. Prone shooting performance decreased (87.5 ± 6.5 vs. 76.3 ± 8.8, points out of 100, p < 0.05) between days 6 and 8 in CON while EXP was able to maintain shooting performance throughout the study.ConclusionA short recovery during a strenuous training can prevent the degradation in psychophysiological state and shooting performance in soldiers, which can be crucial for survival in demanding operational winter environment. In the present study, 36-h rest period during the field training seems to enhance recovery but the duration of the period was inadequate for full recovery from the accumulated operative stress. In conclusion, appropriate recovery periods should be implemented in order to optimize occupational performance during high operative stress.

Hungarian indigenous Tsigai, a promising breed for excellent heat tolerance and immunity

The adverse effects of climate change on sheep farming have become more noticeable in recent decades. Extensive efforts have been made to untangle the complex relationship between heat tolerance, animal health, and productivity, also to identify a resilient and economically suitable breed for selection that can be resilient to future climate change conditions. Using quantitative real-time polymerase chain reaction (qRT-PCR), we observed the seasonal variations in the expression of several important genes related to heat stress and immunity (HSP70, IL10, TLR2, TLR4, and TLR8) in three of the most widely kept sheep breeds in Hungary: The indigenous Tsigai, Hungarian Merino, and White Dorper. We found that the seasonal stressor affected the relative gene expression of all genes in this study. Notably, The Hungarian indigenous Tsigai was the most robust breed adapted to the Hungarian continental (hot summer, cold winter) environment, with excellent thermotolerance and immunity. Furthermore, despite suffering from heat stress in the summer, Hungarian Merino maintained their robust immune system well throughout the year.

Effect of energy renovation on indoor air quality and thermal environment in winter of a primary school in a highly polluted French alpine valley

Effect of energy renovation on indoor air quality and thermal environment in winter of a primary school in a highly polluted French alpine valley

Physical Environment Study on Social Housing Stock in Italian Western Alps for Healthy and Sustainable Communities

Climate change has reduced the comfort of community environments, and there is an urgent need to improve the health and well-being of low-income residents through design and technical measures. Therefore, this paper conducts research in the context of an ongoing social housing renovation project in Aosta, Italy, in a cold winter and hot summer Alpine environment. The study combined interviews, field measurements, and multiple software simulations to analyze the home of an older adult experiencing energy deprivation. The study found that the indoor acoustic environment quality meets the requirements of various sound-related standards. Still, the lighting and thermal environment must be designed to reduce glare and western sun exposure, and the air quality could improve. Residents’ demand for renovation is low technology, low cost, and high comfort. Therefore, suggestions for combining active and passive transformation measures and maximizing the use of climate and resources are proposed. The lighting and thermal environment are optimized based on the green wisdom of the Haylofts building of the Walser family in the Alps: increase ventilation and reduce indoor air age to improve air quality. Overall, a comprehensive assessment of extreme climatic conditions facilitates the quantitative and qualitative study and control of social housing environments, improves occupant comfort, and decarbonizes such social building stock.

Application of an Architect-Friendly Digital Design Approach to the Wind Environment of Campus Dormitory Buildings

Good natural ventilation can improve the comfort of campus dormitories and effectively avoid pollution caused by particle accumulation. Parametric design can effectively address the feedback and connection between building performance analysis and design. This study employs an architect-friendly digital design method based on the Rhino/Grasshopper parametric platform. It takes campus dormitories in the cold region as a case, using parameterized digital tools, such as the Butterfly plugin to simulate wind performance under three influencing factors: building layout, opening position, and building façade (shape and spoiler). Finally, the optimal design that can simultaneously meet the local winter and summer wind environment requirements is selected and validated. In addition, the reasonable design of external balconies and bathrooms in a dormitory can form buffer spaces to achieve effective wind shelter and insulation effects in cold regions. This article describes how to use digital tools to quickly and easily optimize the design of building forms based on wind simulations to promote campus sustainability.

Numerical study on the influence of floating ice on the water-exit hydrodynamic characteristics of a trans-media vehicle

In low-temperature combat conditions, the strong interference of floating ice on the water-exit process of trans-media weapons must be considered. The evolution of the cavity shape, hydrodynamic and ballistic characteristics during the water-exit process of a high-speed vehicle penetrating water (without floating ice) and ice-water mixture were studied in comparison based on computational fluid dynamics (CFD) and the discrete element method (DEM). The results revealed that the floating ice accelerates the collapse of the attached cavity, delays the collapse time of the tail cavity, and changes the vehicle’s wet degree. The floating ice causes the vehicle to be subjected to a severe fluctuating alternating load and lasts for a longer time, which changes the trajectory characteristics of the vehicle, reducing its motion stability and intensifying trajectory deviation. The findings can provide a reference for the design and development of cross-media weapons in low-temperature environments in winter.

Research on Multiple Energy-Saving Strategies for Existing Coach Stations: A Case of the Xi’an Area, China

In the context of China’s dual-carbon goals, energy efficiency in public buildings has become a focal point of public concern. As large-scale public transportation buildings, the indoor thermal comfort and the current state of energy consumption of coach stations are increasingly being emphasized. This research used existing coach stations in the Xi’an region as the object; through on-site investigations and field tests of indoor thermal environments in winter and summer seasons, it was found that the coach stations had energy waste and high energy consumption; the enclosure structures had poor thermal performance; and the stations lacked effective energy-saving measures. Energy-saving transformation strategies were proposed from two aspects: enclosure structures and renewable energy utilization. Using DeST-C for energy consumption, the external walls, roofs, insulation materials, and glass materials were simulated, and nine different combinations of energy-saving schemes were simulated using orthogonal experiments. The optimal scheme was selected based on the comprehensive energy-saving rate and economic analysis results, which included using 80 mm XPS external insulation for the external walls, low-e hollow glass for the windows (low transmittance type), and an 80 mm PUR board for the roof insulation. The energy-saving rate of this scheme was 26.84%. The use of rooftop solar photovoltaic power generation and fresh air heat recovery devices can effectively reduce building energy consumption, and the investment payback period is less than 5 years. The research applications have practical significance for improving the indoor environment of existing coach stations and saving energy consumption.

Investigation of uterine microbiota in postpartum dairy cows and barn environment by quantitative PCR technique

The objective of this study was to investigate uterine microbiota in postpartum dairy cows and barn environment by quantitative PCR and to evaluate the correlation between the microbiota in the uterus and barn environment. The study was carried out in 2 seasons of the year: summer (June to August 2017) and winter (October 2017 to March 2018) on Holstein dairy cow farm, Okayama Livestock Research Institute, Japan. A total of 116 samples, including 68 uterine and fecal samples, were collected from 9 cows in summer and 8 cows in winter, at 1 and 2 months after calving. Additionally, 48 samples of barn environment including airborne dust, bedding, feed and water samples were collected 6 times throughout each season. The quantative PCR results showed significant differences (P &lt; 0.05) in the uterine and fecal microbiota of dairy cows at 1 and 2 months after calving. In summer, total bacteria at 2 months postpartum were higher than those at 1 month after calving, while total bacteria were the same in winter (P &gt; 0.05). Bacteroidetes and Firmicutes in uterus and feces between 1 and 2 months after calving were not significantly different in both summer and winter (P &gt; 0.05). The populations of Bacteroidetes, Firmicutes, and total bacteria were found to be highest in bedding compared to those in feed, airborne dust, and water from the barn environment (P &lt; 0.05). Bacteroidetes, Firmicutes and total bacteria in uterus were closely related with those in bedding in summer, however they had the negative correlation with the microbiota of barn environment in winter, especially with fecal microbiota.