Winter Region Research Articles

Thermal performance of an active casing pipe macro-encapsulated PCM wall for space cooling and heating of residential building in hot summer and cold winter region in China

Phase change material (PCM) wall is expected to match the building type and its climate region effectively. In order to meet the space cooling and heating of residential buildings in hot summer and cold winter regions in China, a new active casing pipe macro-encapsulated PCM wall is proposed, in which the cold storage and heat storage PCMs are sealed between the inner pipe and outer pipe with no leakage. To obtain the optimal structure parameters and better thermal performance of the PCM wall, the mathematical model of the PCM wall is established and validated by experiment, and the effects of PCM filling pattern, structural parameter of casing pipe, water temperature in inner pipe and indoor setting temperature are simulated and analyzed. The results show that the optimal PCM filling pattern is to fill the cold storage PCM and heat storage PCM in the gap between the inner pipe and outer pipe separately; the optimal PCM filling thickness is 13 mm; the optimal structural parameters are inner pipe diameter of 20 mm and casing pipe centre spacing of 61 mm. The water temperature in the inner pipe and PCM energy storage/release time reasonably match the indoor setting temperature. Under the optimal operating conditions, the average PCM wall surface temperatures of 20.5 and 26.8 ℃ and the PCM wall surface heat fluxes of 45.9 and 57.2 W/m2 can be obtained in summer and winter conditions, respectively. The research provides an optimized casing pipe macro-encapsulated PCM wall system that can reliably and efficiently meet both the space heating and cooling demands of residential buildings in hot summer and cold winter regions in China.

Superficial skin temperature recovery of distal limbs of thoroughbred racehorses after training in a racetrack in different seasons.

In the present study we aimed to investigate superficial skin temperature of racehorses' distal limbs after training in a racetrack. Male and female Thoroughbred racehorses were investigated in summer, after light training, and in the winter, after light and intense training. Horses were exercised (Exercise group, EG) under trainers' protocol while others were maintained inside their stalls (Control group, CG). Thermographic images were obtained from the front (fetlock, cannon, and carpus) and hindlimbs (fetlock, cannon, and tarsus), before exercise and 45, 60, 120 and 180min after exercising. Images were analyzed using the Flir Tools® program. Temperatures of different moments of each group were compared using Anova for repeated measures and each moment of EG versus CG using Student t test. Horses of the CG maintained steady temperature in the winter, but in summer temperature increased at M45 until M180 (P < 0,01). EG increased temperatures after exercises that remained higher than M0 even at 180min post-exercise (P < 0,0001), for most of the regions in winter and summer. EG temperatures were higher than CG at most of the time points after exercise. There was positive correlation between all regions' temperature and the atmospheric temperature for the CG during the summer (P = 0,003, r2 = 0,9622), observed for the front fetlock and carpal regions for the EG (P = 0.035, r2 = 0,8166). This pilot study demonstrates that, after race exercising under natural conditions skin temperature might take more than 180min to return to basal values.

Causal oceanic feedbacks onto the winter NAO

Of the climate variability patterns that influence the weather in the North Atlantic region in winter, the North Atlantic Oscillation (NAO) is the most dominant. The effects of the NAO span from cold air outbreaks to unseasonably warm conditions and unusual precipitation, with significant impacts on human activities and ecosystems. While a connection between the NAO and antecedent sea surface temperature (SST) conditions has been recognised for decades, the precise causal interaction between the ocean and the atmosphere remains enigmatic. In this study we uncover a robust statistical relationship between North Atlantic SSTs in November and the NAO throughout the subsequent winter in the extended ERA5 reanalysis back to 1940. We apply a well-established causal inference technique called mediation analysis, commonly used in social science and now adopted in climate research. This analysis highlights the roles of low-level baroclinicity, latent heat fluxes, and latent heat release in mediating the effect of November SSTs on the NAO in January and February. It is important to recognise that these mediators are interrelated. Moreover, our analysis reveals bidirectional relationships, where the NAO reciprocally mediates the effects of the November SSTs on these variables. This is evidence of a complex web of feedback mechanisms which collectively contribute to the response of the winter NAO to late autumn/early winter SSTs.

Impact of climate change on persistent cold-air pools in an alpine valley during the 21st century

Abstract. When anticyclonic conditions persist over mountainous regions in winter, cold-air pools (i.e. thermal inversions) develop in valleys and persist from a few days to a few weeks. During these persistent cold-air pool (PCAP) episodes the atmosphere inside the valley is stable and vertical mixing is prevented, promoting the accumulation of pollutants close to the valley bottom and worsening air quality. The purpose of this paper is to address the impact of climate change on PCAPs until the end of this century for the alpine Grenoble valleys. The long-term projections produced with the general circulation model MPI (from the Max Planck Institute) downscaled over the Alps with the regional climate model MAR (Modèle Atmosphérique Régional) are used to perform a statistical study of PCAPs over the period 1981–2100. The trends of the main characteristics of PCAPs, namely their intensity, duration, and frequency, are investigated for two future scenarios, SSP2–4.5 and SSP5–8.5. We find that the intensity of PCAPs displays a statistically significant decreasing trend for the SSP5–8.5 scenario only. This decay is explained by the fact that air temperature over the century increases more at 2 m above the valley bottom than in the free air at mid-altitudes in the valley; this might be due to the increase of specific humidity near the ground. The vertical structure of two PCAPs, one in the past and one around 2050, is next investigated in detail. For this purpose, the WRF (Weather Research and Forecasting) model, forced by MAR for the worst-case scenario (SSP5–8.5), is used at a high resolution (111 m). The PCAP episodes are carefully selected from the MAR data so that a meaningful comparison can be performed. The future episode is warmer at all altitudes than the past episode (by at least 4 ∘C) and displays a similar inversion height, which are very likely generic features of future PCAPs. The selected episodes also have similar along-valley wind but different stability, with the future episode being more stable than the past episode. Overall, this study shows that the atmosphere in the Grenoble valleys during PCAP episodes tends to be slightly less stable in the future under the SSP5–8.5 scenario, and statistically unchanged under the SSP2–4.5 scenario, but that very stable PCAPs can still form.

An empirical study of indoor air quality in badminton stadiums in hot summer and cold winter regions of China during spring and fall seasons

The indoor air quality has a direct impact on human health. In order to obtain the current status of indoor air quality in typical sports buildings in hot summer and cold winter climate zones in China, indoor badminton courts in 10 cities in Hubei Province in this climate zone were selected as research objects for field testing of indoor environmental parameters in spring and autumn, and predict air quality parameters for non-testing times. All the tested stadiums are naturally ventilated in non-event conditions, and the average daily indoor CO2 concentration was 526.78 ppm in spring and 527.63 ppm in autumn, and the average daily PM2.5 concentration was 0.035 mg/m3 in spring and 0.024 mg/m3 in autumn, all of which met the requirements of GB/T 18883-2022, the average concentration of CO2 ≤ 1000 ppm and PM2.5 ≤ 0.05 mg/m3. The indoor CO2 concentration and PM2.5 concentration of the tested badminton halls under natural ventilation gradually increased with the accumulation of exercise time, making the indoor air quality of the badminton halls decrease, which would negatively affect the health of the people exercising in this environment.

Connecting Global Modes of Variability to Climate in High Mountain Asia

Oscillations in global modes of variability (MoVs) form global teleconnections that affect regional climate variability and modify the potential for severe and damaging weather conditions. Understanding the link between certain MoVs and regional climate can improve the ability to more accurately predict environmental conditions that impact human life and health. In this study, we explore the connection between different MoVs, including the Arctic oscillation (AO), Eurasian teleconnection, Indian Ocean dipole (IOD), North Atlantic oscillation (NAO), and El Niño southern oscillation (Nino34), with winter and summer climates in the High Mountain Asia (HMA) region, including geopotential height at 250 hPa (z250), 2 m air temperature (T2M), total precipitation (PRECTOT), and fractional snow cover area (fSCA). Relationships are explored for the same monthly period between the MoVs and the climate variables, and a lagged correlation analysis is used to investigate whether any relationship exists at different time lags. We find that T2M has a negative correlation with the Eurasian teleconnection in the Inner Tibetan Plateau and central China in both winter and summer and a positive correlation in western China in summer. PRECTOT has a positive correlation with all MoVs in most regions in winter, especially with the IOD, and a negative correlation in summer, especially with the Eurasian teleconnection. Snow cover in winter is positively correlated with most indices throughout many regions in HMA, likely due to wintertime precipitation also being positively correlated with most indices. Generally, the AO and NAO show similar correlation patterns with all climate variables, especially in the winter, possibly due to their oscillations being so similar. Furthermore, the AO and NAO are shown to be less significant in explaining the variation in HMA climate compared to other MoVs such as the Eurasian teleconnection. Overall, our results identify different time windows and specific regions within HMA that exhibit high correlations between climate and MoVs, which might offer additional predictability of the MoVs as well as of climate and weather patterns in HMA and throughout the globe.

Investigation on Mechanical Properties and Temperature Control Efficiency of Novel Load-Bearing and Heat-Storing Metastructure Walls in Hot Summer-Cold Winter Regions

Investigation on Mechanical Properties and Temperature Control Efficiency of Novel Load-Bearing and Heat-Storing Metastructure Walls in Hot Summer-Cold Winter Regions

Forage Pea Pure Lines: Winter Hardiness, High Seed and Biological Yield

Winter forage pea is a plant that grows in cold climates and is a valuable source of protein for animal feed. In this study, 13 pure forage pea lines (PS3057M1, PS3057M2, PS3073G1, PS3073G2, PS3073G3, PS4028H1, PS4028H2, PS4028H3, PS4028H4, PS4053M1, PS4053M2, PS4053M3 and PS4053M4) and Emirbey and Şahin varieties were used as material. The research was conducted at Selçuk University Prof. Dr. Abdülkadir AKCİN Research and Application Station in the trial fields during the 2020-21 and 2021-22 plant growth periods without irrigation. The trials were established in both years according to randomized block design with 3 replications. Meteorological data indicated that despite variations in the lowest temperatures between the two years, all pea lines remained undamaged. This highlighted the adaptability of forage pea lines to the region's winter conditions, which is consistent with previous studies. Statistically significant differences were determined between the two years of the study in terms of all traits analyzed in the research. Higher values were recorded in the second year for all traits. The main reason for these differences is the precipitation and temperatures in the spring months, which is the period when the plants grow actively. Again, significant statistical differences were determined between the lines in all the traits analyzed in the study. This shows us that genetic traits and environmental conditions are important in determining the traits analyzed in this study. The forage pea lines used in the study performed better than the standard varieties in terms of seed and biological yield. In conclusion, this research shows that newly developed winter forage pea lines can be successfully grown in the Konya region and these lines have important genetic and environmental effects on various yield parameters.

Classification of synoptic processes in the territory of Ukraine using a modified Jenkinson and Collison method

During the year, the territory of Ukraine is under the influence of various synoptic processes, which have a certain evolution in the surface conditions of the region and sometimes lead to the formation of unfavorable and dangerous weather conditions. The classification of synoptic processes makes it possible to create a set of daily synoptic situations taking into account the characteristics of a certain region, both for their use in weather forecasting and for studying the dynamics of regional synoptic processes under climate change. In this study, the modified version of Jenkinson and Collison method is used to classify synoptic processes on the territory of Ukraine, which is based on pressure data at the sea surface level and the geopotential heights at the level 500 hPa. The analysis of the obtained set of daily types of atmospheric circulation for the period 1948-2021 and the composite pressure fields built for each circulation type showed that all synoptic situations are clearly defined according to the classification and have seasonal features of frequency. During the year, advective processes of the western circulation group prevail, eastern advection is also often observed, and this type of circulation dominates in the spring months. The processes of the southern group are most relevant on the cold period of the year. Anticyclones occur more often over the region in winter and autumn, and cyclones are observed in summer and spring. The inclusion of 500 hPa level data in the classification makes it possible to take into account the three-dimensional structure of synoptic objects and distinguish such types of circulation as low cyclones and cold anticyclones, as well as troughs and cut-off lows at heights. It was found that low (thermal) cyclones and anticyclones make up a small proportionof synoptic situations, so the feasibility of their further inclusion in the typification for the territory of Ukraine is being discussed. The processes associated with the cut-off lows at the upper levels turned out to quite rare, but due to the possibility of the formation of dangerous weather conditions, this type of circulation is necessary in the classification of regional synoptic processes.

Moisture sources for precipitation over the Pamirs Plateau in winter and spring

AbstractThe abundant precipitation over Pamirs Plateau (PP) in spring and winter plays a vital role in the water resources over the arid areas of Central Asia. Understanding the moisture sources and water vapour transportation associated with precipitation are very important, but there were few studies investigating the moisture sources of PP. We used a Lagrangian model driven with the Weather Research and Forecasting output to analyse the moisture sources at Northern Pamirs Plateau (NPP) and Southern Pamirs Plateau (SPP) in spring 2016, 2009 and 2001, and in winter 2016, 2010 and 2017, as the seasonal precipitation in PP was the largest, median and lowest during 2001 to 2018, and the precipitation in spring and winter was much higher than that in summer and autumn. The moisture sources from four regions were quantified: Atlantic‐Europe‐Africa, Arctic‐Northern Asia, Indian Ocean, and moisture recycling from the PP. Atlantic‐Europe‐Africa and Indian Ocean are the dominant moisture source regions in spring and winter, which contribute more than 70% to the total moisture affecting the precipitation at PP. The contributions of Indian Ocean are higher at SPP than those at NPP in spring and winter. The contributions from Arctic‐Northern Asia and PP are generally low, except that the moisture from PP region contributed 19% to the spring precipitation at NPP, indicating the importance of a local moisture source in enhancing the spring precipitation at NPP. The moisture contributions originating from the different source regions show great differences between winter and spring. The moisture transportation is affected by westerlies, and the zonal winds in spring affect the moisture transportation, while the meridional winds over the Arabian Peninsula mainly affect the moisture transportation in winter.

Experimental and numerical study of adaptive ventilation and sunlight regulation building envelope combining variable transparency shape-stabilized phase change material

The development of adaptive building envelopes with advanced PCM to reduce building energy consumption is a promising topic. This study proposed an adaptive ventilation and sunlight regulation wall (AVSRW) by combining the variable transparency shape-stabilized PCM (VTSS-PCM), reflective film, and ventilation cavity. The combination of VTSS-PCM and reflective film could passively regulate the solar absorptivity (SA) of AVSRW. The ventilation cavity with airflow control enhanced the heat storage and release efficiency of VTSS-PCM. A dynamic photo-thermal coupling model of the AVSRW was presented and validated by a full-scale experiment in summer and winter conditions. Then, based on the weather data of the typical meteorological year of Changsha, China, the performances of AVSRW on days, months, and a year were evaluated. The impact of three influential factors and their combined effects on the performance of AVSRW were analyzed. Ultimately, a global optimization was conducted to improve the performance of AVSRW, and compared with the massive wall. The results showed that the AVSRW passively decreased its SA on summer days and increased its SA on winter days. The total annual undesired heat exchange (TAHE) of AVSRW first decreased and then increased with the increase of melting temperature (Tm) and thickness (L) of VTSS-PCM. The reflective film had an opposite effect on the annual heat gain (AHG) and annual heat loss (AHL) of AVSRW, resulting in the TAHE remaining unchanged with the increase of reflectivity (R) of the reflective film. The greater the L, the smaller effect of the Tm and R on the AHG and AHL, and the greater the R, the greater effect of the Tm and L on the AHG and AHL. After optimization, the values of the Tm, L, and R corresponding to the optimal solution were 24.60 °C, 0.17 m, and 0.63, respectively. Compared with the reference wall, the AVSRW with the best performance had lower AHG and AHL, and the annual energy-saving rate of the AVSRW reached 43.49%. This study guides the application and parameter optimization of AVSRW in hot summer and cold winter regions.

Bioclimatic Design Strategy in Hot Summer and Cold Winter Region of China

Abstract: The building of ecological harmony with the environment is not only concern in the field of architecture, when we do architectural design, we must respect nature promote the process of natural humanization, and obtain good natural, economic, and ecological comprehensive benefits. The bioclimatic design method can provide the basic direction for the development of building technology. To a certain extent, it is helpful for Chinese architects to objectively analyze the environment of a particular area in the light of their own economic and technological level, the purpose of this study is to provide architects with a macro concept of climate and to summarize practical, experienced and technical methods for the bioclimatic design of buildings and urban spaces. Analyzing domestic and foreign research trends, we can see that the following problems exist in the development of bioclimatic design theory in China.

Performance analyses of a novel free-cooling assisted air conditioning system applied to electrical vehicles

Air conditioning system of electrical vehicles7 consumes much electricity for cooling. Using natural cooling source could effectively reduce energy consumption and extend mileage. In this paper, cooling load characteristics of electric vehicles were analyzed considering influences of climate conditions, and energy saving potential of using natural cooling sources were investigated to provide guidelines for the design of efficient air conditioning systems. First, a typical electrical vehicle was designed as the studying object, and a numerical model was established to calculate vehicle’s cooling load. Utilization ratio of natural cooling in severe cold regions, cold regions, and mild regions ranged from 36.7 % to 47.8 %, while the value was only 2.5 % in hot summer and warm winter areas. Then, a novel natural cooling assisted air conditioning system was proposed, and parametric studies were carried out to study energy-saving ratio and improvement of traveling hours. Average coefficient of performance of the novel system ranged from 4.47 to 6.08 with the air flow rate being 700 m3/h, and ranged from 5.78 to 7.71 with the air flow rate being 2000 m3/h. The values are 7.3 % to 65.8 % higher than the traditional air conditioning system. The electric consumption during cooling period could be reduced by up to 83.7 % in mild regions and by 24.9 % to 57.4 % in severe cold regions, cold regions, and hot summer and cold winter regions. Increasing setting temperature and enlarging air flow rate of the air conditioning system could effectively improve the energy-saving ratio. Traveling hours could be extended by 2.0 % to 15.8 %.

Energetic, economic and environmental analyses of frost-free air-source heat pump in multi-type buildings and different locations

Frost-free air-source heat pumps (FFASHPs) have gained increasing attention as an alternative to conventional air-source heat pumps (ASHPs), chillers and boilers (CBs), in the context of low-carbon space heating and cooling. Conducting energetic, economic, and environmental (3E) analyses on these systems in various building types and locations is crucial for system selection, yet relevant research is scarce. To address this issue, this paper presents a comprehensive framework for 3E analyses, including location selection, building assessment, load calculation, system sizing and modeling, annual simulations, and subsequent data visualization. The study includes seven building types and 353 locations with specific climate conditions. The results indicate that FFASHPs outperform ASHPs in terms of energy efficiency, lifecycle costs, and carbon emissions. Compared to CBs, FFASHPs exhibit superior energy efficiency across most regions and building types, except for severe cold, hot summer and warm winter regions. In central and coastal areas, the advantages are more prominent due to higher natural gas prices, making FFASHPs commercially viable. In hot summer and cold winter region with electricity carbon emission factors ranging from 0.3574 to 0.6829 kgCO2/kW, the FFASHP exhibits significant potential for decarbonization due to its high efficiency. In renewable energy-rich areas with low emission factors (0.1031–0.2602 kgCO2/kWh), FFASHPs can achieve significant carbon reductions, up to 90 %. This paper, for the first time, achieves a comprehensive 3E analyses of FFASHPs, ASHPs, and CBs. It offers a general methodology, extensive datasets, and visualized graphs for system selection, promoting low-carbon space heating and cooling.

Influence of geographical location and outdoor meteorological parameters on indoor humidity environment in rural residential buildings during the Plum Rains Season in the hot summer and cold winter region.

Plum Rains Season (PRS) has the typical characteristics of outdoor air temperature dramatic changes and high air humidity in the hot summer and cold winter region in China. When the outdoor temperature rises rapidly during PRS, the building envelope surface temperature is probably lower than the indoor air dew point temperature, resulting in moisture condensation. This paper evaluates the influence of geographical location and outdoor meteorological parameters on the indoor humidity environment. The effects of critical parameters such as altitude, average temperature, relative humidity, total precipitation, total precipitation days, atmospheric pressure, and wind speed on the building envelope moisture condensation in nine typical cities in the hot summer and cold winter region were simulated and analyzed. The results show that the Condensation Frequency (CFn) in the western, central, and eastern regions reached the highest in April, May, and June, respectively. Among the nine typical cities, Changsha has the highest Condensation Risk (CR). In addition, the altitude, total precipitation, and atmospheric pressure have little effect on the indoor humidity environment, and it is not directly related to CR; The average temperature and total precipitation days were not related to CR in the western and eastern regions and positively correlated with CR in the central region; The wind speed was positively correlated with CR in the western and central regions and negatively correlated in the eastern region; The relative humidity can affect the indoor humidity environment and moisture condensation on the inner surface of walls, when the relative humidity increases, the CR increases.

Comprehensive assessment of building energy consumption in hot summer and cold winter areas based on carbon tax considerations

With the rapid development of economy and urbanization in China, cities are expanding rapidly and more constructions are being built, then lead to the fast-growing part in urban residential energy consumption. In China’s hot summer and cold winter regions, many buildings are not centrally heated and commonly rely on electrical equipment such as air conditioners which are all energy-inefficient thermoregulation devices. In order to analyze the relationship between building energy consumption and the energy efficiency ratio (EER) of air conditioning and the area of photovoltaic (PV) on the roof, the influence of the building envelope on building energy consumption in hot summer and cold winter regions in China is clarified. This paper uses energy plus software to analyze the impact of different EER and PV area on building energy consumption using a typical case study of a public health upgrading project in the eastern part of the Wuxing district, Huzhou, Zhejiang province in China. The simulation results show that the factor that has a greater impact on the energy consumption of the health center in summer is the PV area parameter of the building compared to the performance parameters of the air conditioning equipment. The PV area parameter settings and air conditioning equipment performance adjustments are dependent on the actual situation and the comprehensive energy saving rate of the outpatient building for public health in the eastern part of Tai Wu Xing District can exceed 50%. Finally, an economic analysis of the carbon tax and input costs is carried out, and the best combination is of which 60% of the area covered by Longi Green PV panels and an air conditioning efficiency ratio of 4.87. The research result combines renewable energy and efficient equipment to achieve dual optimization of environmental and economic aspects of building energy consumption, while providing reference opinions on the comprehensive evaluation method of building energy consumption from the perspective of carbon tax.

Multi-objective optimization design of residential area based on microenvironment simulation

In current research on old communities, less attention is given to the comfort and greenhouse gas emissions of the indoor and outdoor physical environment. Only a few studies focus on optimization strategies for these environments in old communities. Thus, the absence of suitable theoretical guidance in specific engineering practices can lead to issues. Renovated old communities still face challenges such as overheating in summer, overcooling in winter, and high energy consumption. In this article, based on the optimization of low- and medium-rise old communities in five typical cities in China, corresponding strategies such as geometric and envelope design parameters are proposed in terms of building greenhouse gas emission and indoor and outdoor thermal environment comfort. Several methods are employed in this study, including parametric simulation using Grasshopper with the Ladybug and Honeybee plugins for data collection. This research conduct sensitivity analysis using Random Forest Regressor (RFR), Gradient Boosting Regressor (GBR) and Decision Tree Regressor (DTR) to explore the relationship between design variables and environmental objectives. Predictive modeling with ensemble models and multi-objective optimization using the NSGA-2 algorithm help identify optimal design parameters for varied urban climates. The results demonstrated indoor and outdoor comfort of communities can be improved to a greater extent while reducing carbon emissions. Quantitatively, compared to the baseline model, all cities except Wuhan can improve the year-round comfort time of the outdoor thermal environment by more than 50%. Besides, communities in hot summer and warm winter regions (e.g. Shenzhen and Nanning) can reduce their annual carbon emissions by more than 300t, and communities in hot summer and cold winter regions (e.g. Hangzhou, Chengdu and Wuhan) can reduce their annual carbon emissions by more than 100t. The research results will serve as a scientific basis for energy saving and emission reduction and provide decision-making methods for the development of old communities.

Adaptability law of central heating environment under the effect of thermal history: A continuous field survey

Creating an optimal indoor thermal environment that meets the needs of diverse populations is a crucial aspect of building design. Given the escalating frequency of population migration and the widespread adoption of centralized heating systems, it is important to establish the effects of various prior thermal histories on human adaptability to centralized heating environments. In this study, 15 subjects with no prior experience of heating in hot summer and cold winter regions (HSCW) and 13 subjects with prior experience of heating in cold regions (C) were selected for a 40-day follow-up study at a university in Qingdao. In total, 992 valid responses were obtained from the questionnaires. The results indicated that prior thermal history had a notable influence on thermal perception in centrally heated environments, with those lacking heating experience reflecting a better initial perception of heat. Specifically, in a classroom environment, the differences between the two groups, in terms of thermal sensation, thermal acceptability (percentage of acceptance), and thermal expectation (percentage of desiring “warmer”) decreased from 0.26, 12%, and 19% in the first cycle to 0.03, 2%, and 3% in the fourth cycle (25–32 days), respectively. The difference in thermal comfort also reduced from 0.23 in the second cycle (9–16 days) to 0.04. Similar trends were observed in the dormitory environment, indicating that the duration of the impact of heat experience on adaptation to the centrally heated environment was 32 days. The results of this study are useful for describing the dynamic thermal acclimatization of different populations in unfamiliar thermal environments and for providing indoor thermal environments that match the thermal preferences of residents with different thermal experiences.

Impacts of Thermal Drainage on Bacterial Diversity and Community Construction in Tianwan Nuclear Power Plant.

As one of the low-carbon and high-efficient energy sources, nuclear power is developing vigorously to alleviate the crisis of global climate warming and realize carbon neutrality goals. Meanwhile, the ecological effect of thermal drainage in the nuclear power plant is significantly remarkable, which environmental assessment system has not yet referred to microorganisms. The rapid response of microbial diversity and community structure to environmental changes is crucial for ecosystem stability. This study investigated the bacterial diversity, community construction, and the co-occurrence patterns by 16S rRNA gene amplicon sequencing among gradient warming regions in Tianwan Nuclear Power Plant. The alpha diversity of the high warming region was the lowest in summer, which was dominated by Proteobacteria, whereas the highest bacterial diversity presented in high warming regions in winter, which harbored higher proportions of Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. The spatial distribution of bacterial communities showed clear separation especially in summer. Strong correlations were between community compositions and environmental factors, such as salinity, DO, TN, and temperature in summer. Furthermore, remarkable seasonality in bacterial co-occurrence patterns was discovered: the robustness of the bacterial co-occurrence network was promoted in winter, while the complexity and robustness were decreased in summer due to the warming of thermal drainage. These findings reveal the potential factors underpinning the influence of thermal drainage on bacterial community structure, which make it possible to predict the ecological effect of the nuclear power plants by exploring how the microbial assembly is likely to respond to the temperature and other environmental changes.

The impact of bedroom environment on sleep quality in winter and summer in the Qinghai-Tibetan plateau

The special climatic environment at high-altitude results in common sleep problems for the local inhabitants. Analyzing the relationship between bedroom environment and sleep at high-altitude is one way to improve sleep quality. This study investigated the bedroom environment and sleep quality of plateau dwellers in the Tibetan Plateau region in winter and summer respectively. One hundred and ninety-seven healthy local residents participated in a 1-week bedroom environment and sleep monitoring, resulting in a total of 690 person nights of valid data. The results showed that high-altitude environment caused more wakefulness after sleep onset compared to the NSF recommendation. Sleep of high-altitude residents in summer was associated with more environmental parameters in the bedroom. High Ta, high RH and high CO2 in summer exacerbated the decrease in sleep efficiency and deep sleep duration, with CO2 being the more dominant environmental factor. In winter, the dry environment reduced the length of light sleep for the highlanders, leaving them more sleep deprived when indoor heating was available.