Average Air Temperature Research Articles

The Scientific Case Against Net Zero: Falsifying the Greenhouse Gas Hypothesis

The UK Net Zero by 2050 Policy was undemocratically adopted by the UK government in 2019. Yet the science of so-called ‘greenhouse gases’ is well known and there is no reason to reduce emissions of carbon dioxide (CO2), methane (CH4), or nitrous oxide (N2O) because absorption of radiation is logarithmic. Adding to or removing these naturally occurring gases from the atmosphere will make little difference to the temperature or the climate. Water vapor (H2O) is claimed to be a much stronger ‘greenhouse gas’ than CO2, CH4 or N2O but cannot be regulated because it occurs naturally in vast quantities. This work explores the established science and recent developments in scientific knowledge around Net Zero with a view to making a rational recommendation for policy makers. There is little scientific evidence to support the case for Net Zero and that greenhouse gases are unlikely to contribute to a ‘climate emergency’ at current or any likely future higher concentrations. There is a case against the adoption of Net Zero given the enormous costs associated with implementing the policy, and the fact it is unlikely to achieve reductions in average near surface global air temperature, regardless of whether Net Zero is fully implemented and adopted worldwide. Therefore, Net Zero does not pass the cost-benefit test. The recommended policy is to abandon Net Zero and do nothing about so-called ‘greenhouse gases’.

Climate Response and Radial Growth Dynamics of Pedunculate Oak (Quercus robur L.) Plus Trees and Their Half-Sib Progeny in Periods of Severe Droughts in the Forest-Steppe Zone of Eastern Europe

The dendrochronological parameters of 97 pedunculate oak (Quercus robur L.) trees including 20 plus trees (142-year-old on average) and four half-sib families for four of them were analyzed considering also specifically years of the most severe droughts that were identified using average monthly air temperature and precipitation data. The tree-ring width (TRW) was mostly affected by air temperature that had the largest cross-dating indices (CDI), up to 78% maximum. However, the 32-year Brückner–Egeson–Lockyer cycle (a climatic cycle of approximately 30–40 years that correlates with sunspot activity) was more reflected in the TRW dynamics in plus trees than precipitation and air temperature. A high-frequency of abnormal TRW was clearly observed during drought periods and in the following 2–3 years. Tree radial-growth reduction due to drought stress varied significantly between families. The resistance to drought based on TRW was higher in the maternal plus oak trees than in progeny. Drought resulted in reduced growth during the subsequent year(s); hence, the minimum growth occurred after the actual climate event. Autumn–winter precipitation and weather conditions were of the greatest importance at the onset of active vegetation in April and May. The influence of air temperature on oak growth was the largest in March (r = 0.39, p < 0.05). The strongest positive correlation between precipitation and growth (with r up to 0.38) was observed in May 2023. Plus trees had a high adaptive potential due to the stability of radial growth during drought with high resistance (Rt = 1.29) and resilience (Rs = 1.09) indexes. The offspring of families 1 (Rt = 0.89, Rs = 0.89) and 2 (Rt = 1.04, Rs = 0.87) had similar resistance and resilience, but the recovery indices (Rc) for offspring in families 1, 2 and 3 exceeded the recovery values for plus trees. For offspring in families 3 and 4, the index values were lower. The revealed responses of wood growth of plus trees to climatic parameters estimated as resistance (Rt), resilience (Rs) and recovery (Rc) indexes and similar responses in their progeny can be used in breeding pedunculate oak for wood growth productivity and drought resistance.

The Brazilian case as a beacon to increase crop production in sub-Saharan Africa

Abstract Maize is one of the major agricultural commodities in the world, and a source of food in Africa, representing more than 40 million ha currently harvested on the continent. Despite sub-Saharan Africa's dependence on grain, the maize actual yield (Ya) of the crop is low when compared to its potential yield. In Brazil, the yield-gap between Ya and water-limited yield (Yw) is approximately 50% of Yw. The objective of this study was to carry out a case study, using upland maize as a reference to identify a set of agricultural areas with similar soil and climate in Brazil and sub-Saharan Africa (SSA). The climatic similarity between Brazil and SSA countries was verified, seeking homogeneous climatic zones that occur in both regions. The Ya was determined including the data of at least the last three years of cultivation and were taken from the database of the national institutes of agricultural statistics. The climatic data showed that the SSA had well-distributed rainfall throughout the crop season, being higher than in Brazil, as well as the average air temperature. The average Yw was 11.3 and 7.4 Mg/ha for Brazil and SSA, respectively. Maize Ya in SSA was 1.4 Mg/ha, while in Brazil Ya was 5.2 Mg/ha. Ya represented approximately 9% of Yw in the SSA. The low Ya shows the large yield-gap found in SSA. With this, it is evident that the technologies used and the crop management are largely responsible for the yield differences between Brazil and SSA.

A new quantitative method for evaluating the impact of garden greening on outdoor thermal environment in summer - A case study of Japanese residential gardens

Garden greening can improve the outdoor thermal environment of buildings, but there is a lack of quantitative research on this aspect. First, this research quantitatively analyzes the effect of garden greening on the outdoor thermal environment by conducting field measurements at various distances from measurement points set up in a traditional Japanese residential garden during the summer, and a TDTE model was established. The results show that the outdoor thermal environment evaluation indices at each measurement point reach the maximum value of 13:00 daily. The outdoor thermal environment evaluation indices such as the average air temperature value at the nearest measurement point to the garden greening were 12 % lower than those at the farthest measurement point. Secondly, the TDTE model was established based on this foundation, and the validation of the measured data showed that the TDTE model had high reliability (the average RMSE value was 1.791, and the average MAPE value was 2.978). Finally, the model can provide ideas as well as the theoretical basis for quantitative research related to greening and outdoor thermal environments. This research provides scientific guidance for planning as well as reconstruction of residential garden greening.

Multiplet relaxation transitions in fluorurethane coating after climate aging

The relaxation transition from a glassy to a highly elastic state (α-transition) of a fluoropolyurethane coating deposited on the surface of VPS-48/778 glass fiber reinforced plastic was studied using the method of dynamic mechanical analysis. It is shown that the relaxation maximum of the dynamic loss modulus in the initial state is a superposition of α1-, α2-, α3-transitions, corresponding, respectively, to transitions from the glassy to highly elastic state of VE-69 enamel and EP-0215 epoxy primer. The transition temperature α1, which is the glass transition temperature of fluoropolyurethane VE-69, after 3 years of exposure decreases in proportion to the average annual air temperature of the region. The transition temperatures α2 and α3 after full-scale exposure due to post-curing increased by 13−15°C and acquired stable values α2 = 99 ± 1°C, α3 = 122.5 ± 0.5°C, regardless of the climatic conditions of the tests.

Impact of Site Conditions on Quercus robur and Quercus petraea Growth and Distribution Under Global Climate Change

Climate change has significant natural and economic implications, but its extent is particularly challenging to assess in forest management, a field which combines both of the previous aspects and requires the evaluation of the impact of climate change on tree species over a 100-year timeframe. Oaks are among the tree species of significant natural and economic value in Europe. Therefore, the aim of this study was to analyze all oak stands in Poland and verify the hypothesis regarding differences between Quercus robur and Quercus petraea stands in terms of soil type, annual total precipitation, average annual air temperature, and the length of the growing season. Additionally, this study aimed to analyze the impact of these differences on the growth rates of both oak species and test whether climate change may affect oak stands. A database containing 195,241 tree stands, including different oak species with varying shares in the stand (from 10% to 100%), was analyzed. A particular emphasis was placed on Q. robur and Q. petraea. The results show that, although both oak species have a wide common range of occurrence, there are clear differences in their habitat preferences. Based on the ordinal regression analysis of selected oak stands, it was concluded that an increase in air temperature of 1 °C could impair the growth of Q. robur and slightly improve the growth of Q. petraea. This may indicate the possibility of expanding the geographic range of sessile oaks towards the east and northeast under warming climatic conditions, provided that appropriate moisture conditions are maintained.

Individual tree mortality: Risks of climate change in the eastern Brazilian Amazon region

The mortality of trees in humid tropical forests plays a fundamental role in understanding forest development, particularly after disturbances such as those caused by logging and extreme weather events. The aim of this study was to evaluate estimates of individual tree mortality following Reduced Impact Logging (RIL) in the Eastern Brazilian Amazon at biennial intervals from 2005 to 2012. RIL is based on operations planning, personnel training, and investments in forest management, and harvesting through RIL must: (a) minimize environmental damage, (b) diminish operation cost by increasing work efficiency, and (c) reduce operational waste. A mortality model was constructed based on the estimation of three distance-independent competition-indices (DII) and five models for predicting the probability of individual tree mortality. The Kolmogorov-Smirnov statistical test was used to determine the most representative model, from which a Neural Network Autoregressive (NNAR) model was constructed to forecast mortality after RIL. Mortality data was correlated with the El Niño–Southern Oscillation (ENSO) and climate (Rainfall, Maximum, Minimum, and Average air temperature). The tested models showed similar and accurate estimates with R2 exceeding 0.90, although underestimation and overestimation trends were observed. The NNAR satisfactorily represented species mortality over the simulated years. The period from 2012 to 2014 was characterized by a Neutral and Weak El Niño event, and exhibited the highest mortality value for a 25 cm DBH (diameter at breast height), the smallest DBH class measured in this study. In the correlation matrix analysis, maximum air temperature showed the highest positive correlation with trees mortality. Despite the challenges in estimating individual tree mortality in tropical forests after selective logging, accurate estimates were achieved using traditional regression techniques and NNAR. These results can support technical and silvicultural decisions regarding forest management in the Eastern Amazon region of Brazil.

Microscale urban heat variability and time-location patterns: Elevated exposure for bikers and rickshaw drivers beyond average city temperatures in megacity

Urban heat island effect creates diverse microclimates, influencing heat exposure and consequent health effects. Study measured heat exposure among delivery riders within their microclimate, comparing it with city's average temperature. We investigated how higher exposure affects work, health, and productivity of riders.For 21 days in winter and summer, we measured heat exposure during peak hours (under sun and shade) in riders' immediate environment, at seven high-traffic routes in Karachi, Pakistan. Recorded temperature were compared with city's ambient air temperature. In-depth interviews were conducted to assess the impacts on riders' health, welfare, and productivity.During winter, temperature was 5.0 °C higher under sun and 1.6 °C higher under shade, as compared to city average recorded temperatures. In summer temperature was 5.5 °C higher under sun and 1.8 °C higher in shade as compare to recorded city's average air temperature. Riders reported exhaustion, reduced productivity, income loss, and negative impacts on social wellbeing during hot days. For mitigation riders relied on strategies like staying hydrated and taking breaks from work under shades. Study demonstrated higher exposure to heat for riders in megacity as compare to city's recorded temperature. This led to reduced productivity and income losses, emphasizing need for urgent initiatives to safeguard riders' well-being.

Simulation Study on Heat and Moisture Transfer in Cross‐Flow Drying Aeration of Bulk Corn in a Cone‐Bottom Silo Using Natural and Low‐Temperature Air

ABSTRACTUsing variable temperature and relative humidity of natural air based on local climatic conditions for natural drying aeration of grain is an energy‐saving and efficient method. The study of heat and moisture transfer within grain piles during natural air and low‐temperature air drying aeration of bulk corn in low‐humidity areas, which can provide theoretical support for selecting efficient and low‐consumption grain drying processes and practical applications. In this study, the mathematical model of the coupled heat and moisture transfer dynamics in the dry silo was verified using experimental datum of grain storage drying aeration experiment, and the relative error was less than 5% between the simulated and the experimental datum. Based on this validated model, the temperature and moisture content variations of in‐silo bulk corn drying were simulated by computational fluid dynamics (CFD) numerical simulation techniques. The simulations included continuous drying aeration with daily average, hourly average temperature and relative humidity of the local natural air, and low‐temperature air drying aeration with heated up to 3°C over the ambient temperature, as well as intermittent drying aeration. Drying effectiveness and economic efficiency were also analyzed and evaluated. The costs for continuous drying aeration with hourly average of natural air and low‐temperature, intermittent drying aeration with hourly average of natural air are 0.032, 0.042, and 0.016 CNY/kg, respectively. Compared to traditional high‐temperature hot air drying, the costs of these methods were reduced by 0.048, 0.038, and 0.064 CNY/kg, respectively.

Thermal performance of a double-layer pipe-embedded phase change wall system in wood structures coupled with solar energy

In this study, we propose a dual-layer, pipe-embedded phase change wall system for wooden structures that integrates sky radiation cooling and solar heat collection for cross-seasonal operation. This system harnesses renewable energy and reduces the operational energy consumption of buildings. The primary focus of this study is the performance improving of the system during winter conditions. In winter, the system captures solar energy for daytime indoor heating and load reduction and stores excess heat in phase-change material (PCM) embedded within the wooden wallboard. The stored heat is then released at night to further reduce building loads. To assess the thermal performance of the proposed wall system under winter conditions, experiments were conducted across four different scenarios and a reference system was established for comparative analysis. The results indicate that the proposed wall system significantly improves the indoor thermal environment. Specifically, this integration increased the average indoor air temperature by 6.0 °C compared to the reference system and substantially increased the temperature of the wallboard. The inclusion of PCM notably enhanced the thermal performance by reducing nighttime heat loss. Consequently, the average indoor temperature in systems equipped with PCM-enhanced wallboards was 3.0 °C higher than that in the reference system.

Analysis of natural and man-made factors of landslide development in the Carpathian region using GIS

Purpose. Determination of the dependencies of spatial relationships between landslides in the Carpathian region of Ukraine and the factors causing them, taking into account the differences in geomorphological, geological, climatic conditions and natural and geographical zoning according to the landscape principle. Methodology. The morphometric analysis of the territory was carried out using QGIS tools to determine the slope angles and exposure; linear characteristics were calculated: distances to the river, road, and houses. Based on the image interpretation data, we calculated the total annual rainfall and average annual air temperature. The impact of the factors considered on landslide formation was assessed using multivariate statistical analysis: factor analysis and linear multiple regression. Findings. Studies on the impact of natural and topographical conditions and anthropogenic activity on the development of landslide processes have been conducted. Orographic and climatic factors play the most important role. Construction of business facilities results in a decrease in the slope stability in 14–19 % of cases. The analysed independed factors showed good consistency between the distribution of existing landslides and the parameters under consideration: the share of the total variance of the factors under consideration is 71–76 %, the coefficient of determination of the regression model is 0.7. Based on the results of geoinformation and statistical analyses, it is proved that differences in geomorphological conditions and human activity (construction of roads, economic facilities) are dominant in the formation of landslides in different landscape zones. Originality. It is established that there is a dynamic coherence between the spatial change in natural conditions and human settlement and activity, which interact with each other to create prerequisites for the development of landslides. Practical value. This study is important from the point of view of understanding and mitigating the cause-and-effect relationship of landslide development for certain territories, and the results obtained can be useful in developing land use planning strategies, infrastructure development, and planning new construction works.

Research on the Green Construction Technology of Stilt Houses Based on the Climate Adaptation of Transitional Seasons

Stilt houses are extremely adaptable to terrain and climate. However, current indoor thermal environment research in transitional seasons is not prominent. Therefore, in this research, a typical stilt house in southwest China was chosen as the research object and analyzed by combining Climate Consultant climate analysis software and field measurement data. The results showed that the indoor thermal stability of a stilt house was excellent during the transition season, and the attic had the most obvious climate regulation, with the maximum temperature difference between indoors and outdoors being 9 °C when the outdoor temperature was the highest. The difference between the mean radiant temperature and the average air temperature was only 0.04 °C, and the radiant effect of the enclosure on the interior was small. The indoor relative humidity ranged from 63.2% to 85.1%, showing high relative humidity, but the fluctuation was relatively stable. Stilt floors did not play a significant role in climate regulation during the transition season, and the semi-open space structure was more prone to moisture accumulation when the outdoor humidity was high. Regarding practical application, the climate adaptation strategies of shading, cooling, and dehumidification were applied in the transition season, but dehumidification was ineffective.

Changes in Water Surplus or Deficit and Possible Drivers in the North China Plain During 1961–2022

ABSTRACTIn the North China Plain (NCP), the assessment of water surplus or deficit (WSD), which is calculated as precipitation minus reference evapotranspiration (ET0), holds significant implications for water resource management and agricultural irrigation decision‐making, given the region's long‐standing severe shortage of water resources. However, the magnitude, trend and climatic drivers of WSD remain poorly understood in the NCP. This study analysed the spatial and temporal characteristics of WSD, and quantified the contribution of climatic factors to WSD based on the sensitivity and contribution rate analysis methods with climatic data from 75 meteorological stations. The result showed that: (1) Annual WSD decreased mainly in northeastern NCP and increased significantly in southern NCP during 1961–2022. Annual WSD increased slightly from 1961 to 2022 at a rate of 1.63 mm a−2 mainly due to the more significant decrease (−1.88 mm a−2) in ET0 compared to precipitation (−0.25 mm a−2). (2) In terms of the sensitivity of WSD to climatic factors, relative humidity had the highest sensitivity, followed by net radiation, wind speed, precipitation and average air temperature. (3) Significant declines of wind speed were the most dominant factor affecting WSD variation in most part of NCP during most of a year, and net radiation of four stations in the western high‐elevation regions played the most important role. This study enhances comprehension of the impact of climate change on WSD in the NCP and provides a reference for improving management of agricultural water resources under NCP's evolving climatic conditions.

Distribution of Najadaceae Species in Trans-Baikal Area Due to Climatic Factors

According to data of the late 20th century in the Trans-Baikal and Baikal areas, the family Najadaceae is represented by four species known in few localities: Caulinia flexilis (4 localities), C. minor (3), and Najas major (3), N. marina (4). All of them are annuals, r-strategists, which are characterized by fluctuations in abundance. Since the 21st century, these species have been found in 20 more localities, mainly situated within the Baikal Depression. In 2015, when performing monitoring studies of aquatic flora, three more new localities of Caulinia flexilis, C. minor, and Najas major were found in the basin of the Amur River. Distribution maps of the Najadaceae species in the region were compiled, and the ecological characteristics of their habitats were given. In Trans-Baikal area, since the middle of the 20th century, warming has occurred due to an increase in the average annual temperature. For the last 70 years, aridization has increased in southern regions, which changes the habitat conditions in waterbodies. Findings of these Najadaceae species in Trans-Baikal area coincided with the periods of increase in mean annual air temperatures and with local minimums of precipitation. An increase in the number of findings of the Najadaceae species since the beginning of the 21st century, both in Trans-Baikal area and in other regions of Russia, has been occurring against the background of an increase in the average annual air temperature. In Trans-Baikal area, the trend of increasing of temperatures in the warm season since the beginning of the 21st century is favorable for these species and may contribute to their further distribution.

Effect of Temperature on Black Carp (Mylopharyngodon piceus) Age at Sexual Maturity

ABSTRACTBlack Carp (Mylopharyngodon piceus) is one of the four invasive Asian Carp species (Bighead Carp, Hypophthalmichthys nobilis; Grass Carp, Ctenopharyngodon idella; and Silver Carp, Hypophthalmichthys molitrix) in North America. As benthic predators, Black Carp poses ecological risks to unionids within the Great Lakes and could bring other changes to local benthic communities. One means of assessing invasion risk and potential impact is to determine how critical life history characteristics depend on environmental conditions in new regions. Age at sexual maturity is negatively correlated to the maximum per capita population growth rate and thus can be used to estimate potential population growth for invasive species. Previous studies have found a significant negative relationship between age at maturity and temperature for all three other Asian Carp species, but not for Black Carp. With a more comprehensive dataset, we demonstrate that the same relationship exists for Black Carp. Winter duration is the best predictor of Black Carp age at maturity, followed by average winter air temperature. This significant relationship between age at maturity and temperature was not altered in artificial growing environments. Our results suggested that for Black Carp, temperatures in the winter months are more important for its energy accumulation and maturation and may determine invasion risk in northern locations, such as tributaries of the Great Lakes.

Xylotrophic Agaricomycetes Monitoring in Some Types of Spruce and Birch Forests (Subzone of the Southern Taiga, Perm Territory, Russia)

We have summarized the results of xylotrophic agaricoid basidiomycetes long-term monitoring in some types of indigenous and derived forests in the southern taiga subzone of Perm Krai. We carried out the research by a stationary method on the test 50×20 m areas, one in each type of forest: spruce forest at the brook, sorrel spruce forest and birch forest. We did the work in three periods: I – 1975–1977, II – 1994–1996, III – 2010–2012. The collection of material was carried out annually: in August 3 times with an interval of 10 days (the species composition, number and air-dry biomass of basidiomes were taken into account), and in September once (only the species composition of fungi was taken into account). To date, we have established that the number of xylotrophic agaricoid fungi in the studied forest types varies from 60 (sorrel spruce forest) to 66 (birch forest). Most of the identified species belong to the Tricholomataceae family (37.7–43.3% of the total number of xylotrophic fungi species in each of the biogeocoenoses). There was an annual accumulation of detectable fungal species, with the largest number of species (67–75%) detected from 2 to 9 times, and 2–3% of them were permanent, occurring annually. There was relative stability of the species composition of higher vascular plants (Jaccard generality coefficient: J = 56–88) over time and more significant changes in the species composition of xylotrophic fungi (J = 36–50). The spruce forests had the most similarity of fungi species composition between the cenoses by periods (J = 44–52), and for the entire observation period, the sorrel spruce forest and birch forest had the maximum Jaccard index between cenoses (J = 56). The yield of xylotrophic agaricoid fungi in the studied cenoses varies by years of observation. The birch forest had the largest number and biomass of basidiomata for all the three periods of the research. A decrease in the number of basidiomes of xylotrophic fungi in the sorrel spruce forest was established with an increase in the average monthly air temperature in August (Spearman correlation coefficient: rs = −0.70). The sorrel spruce forest was the most favorable for the biota of xylotrophic agaricoid basidiomycetes, both in number (Shannon index: H = 1.23) and in biomass (H = 1.20), during all the research, since the biota of xylotrophes of the specified cenosis was more diverse and its components were most aligned.

Application of meta-heuristic hybrid models in estimating the average air temperature of Caspian sea coast of Iran

The rise of industrial societies leads to higher greenhouse gas emissions, profoundly affecting the climate in coastal regions. Consequently, air temperature readings from standard meteorological stations are key indicators of the Earth's environmental condition. Therefore, accurate estimation of daily temperature in each region is one of the important prerequisites for agricultural planning as well as water resources management and drought prevention, which can be done in different ways such as experimental, semi-experimental and intelligent models. In this research, WSVR, AIG-SVR, GWO-SVR and BAT-SVR hybrid models were investigated and evaluated in order to estimate the average daily air temperature on the shores of the Caspian Sea located in the north of Iran. For modeling, weather station data from Babolsar meteorological station located in Mazandaran province were used. During the water year from 2012 to 2022, daily parameters including relative humidity, maximum temperature, minimum temperature, wind speed, and evaporation were selected as network inputs, with the average daily air temperature as the network output. To assess and compare model performances, several criteria were employed including correlation coefficient, root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliffe efficiency (NSE), and percentage bias. Comparative analysis revealed that the WSVR model surpassed other models, demonstrating the highest correlation coefficient (0.992), lowest RMSE (0.096), and lowest MAE (0.042). The highest Nash Sutcliffe criterion (0.996) and bias percentage (0.001) were prioritized in the validation stage.

ПОВТОРЯЕМОСТЬ АДВЕКТИВНО-РАДИАЦИОННЫХ ТУМАНОВ НАД АПШЕРОНСКИМ ПОЛУОСТРОВОМ (АЗЕРБАЙДЖАН)

The article examines the physical and meteorological characteristics of advective-radiation fogs formed on the Apsheron Peninsula and nearby islands, including the dependence of atmospheric elements that influence the formation of fogs on the meteorological visibility range, monthly and long-term fog trends. For this purpose, the initial data of aviation meteorological stations in the water area for 1999...2022 were used. The absence of a large morphometric unit on the Apsheron Peninsula and the archipelago, surroundings by the sea, and air masses affecting the area throughout the year determine its synoptic conditions. With the help of physical-meteorological and mathematical-statistical analyses, it has been established that the bulk of advective-radiation fogs formed in the Apsheron waters are repeated in march...april. With this type of fog, it has been established that the range of meteorological visibility varies depending on wind speed and sky conditions. During the period of advective-radiation fogs, south-eastern winds are most often observed in the water area. Analyzes show that an increase in average monthly and annual air temperatures on the peninsula has recently affected the frequency of advective-radiation fogs. Studying the spatiotemporal distributions of fogs can create conditions for the effective organization of aviation work.

THE IMPACT OF EXTREME WEATHER EVENTS OF PROJECTED CANADIAN REGIONAL CLIMATE MODEL DATA ON FLEXIBLE PAVEMENT

This paper presents findings about the influence of projected data from the Canadian regional climate model on the performance of flexible pavement, building upon the results from previous work where the data was generated and published, in which a general trend of decreasing the design life was observed. Projected temperature is the most important extreme climate impact on flexible roads. Adopting a conservative approach demonstrated that two extreme events of Maximum Mean Annual Air Temperature (MMAAT) and Maximum Summer Average Air Temperature (MSAAT) resulted in significant reduction of 25 years road design life. The observed trend indicates a severity range of 7% to 15% in terms of design service life loss when considering events every year compared to every five years. The findings revealed a reduction in pavement design life by 34%, 50%, 73%, and 90% for historical, short, intermediate, and long-term life cycles in the city of Windsor, respectively.

Experimental and numerical research on the thermal performance of a vertical earth-to-air heat exchanger system

The Earth-to-Air Heat Exchanger (EAHE) system is an efficient and clean geothermal application technology that can be used for pre-cooling in summer and heating in winter. This paper proposes a novel Vertical Earth-to-Air Heat Exchanger (VEAHE) system that uses baffles to divide the vertical duct into two ventilation tunnels with a hollow area at the bottom for air circulation. This system occupies a small land area and has a relatively high geothermal energy utilization efficiency. This study evaluates the thermal performance of the system through experimental tests under various operating conditions. Additionally, a numerical model of the system was established to explore the influence of baffles length, thickness, and duct depth on its thermal performance. The experimental results show that the 2.5-meter deep VEAHE system achieves an average air pre-cooling temperature reduction of 5.42 °C, with a maximum temperature reduction of up to 7.58 °C. Below the 1.2-meter mark of the system, the cooling capacity of the descending pipe is 1.52 times that of the ascending pipe. The simulation showed a Maximum Absolute Relative Error (MARE) of 3.15 % compared to the experimental results. As the length and thickness of the baffles, duct length, and soil thermal conductivity increase, the average outlet air temperature gradually decreases, while the system's heat exchange capacity significantly improves, in contrast to the duct diameter. Among the influencing factors, the duct length has the greatest impact on the system. Under the recommended configuration, the system's maximum pre-cooling potential is 915.90 W, with the outlet air temperature ranging from 12.05 °C to 14.79 °C.