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Soil organisms play a key role in carbon and nutrient cycling in forest ecosystems. While soil organisms are strongly influenced by litter chemistry and are highly sensitive to abiotic conditions, little is known about the interactive effects of these two factors. To address this gap in knowledge, we conducted a 10 week microcosm experiment in which we simulated the effects of climate change on soil ecology. More specifically, we studied relationships among litter nutrient concentration, microbial biomass, Collembola demographic parameters, and litter decomposition, exploring the potential impacts of increasing air temperature and decreasing soil moisture. To develop a gradient of nutrient concentrations, we created six tree litter mixtures with materials gathered from Quercus pubescens and its companion species. In contrast to microbes, we observed that Collembola abundance and litter decomposition were interactively affected by soil moisture and air temperature: the negative effect of increasing air temperature on Collembola abundance was amplified by reduced soil moisture, whereas the positive effect of increasing air temperature on litter decomposition disappeared under reduced soil moisture conditions. In contrast to fungi, the response of bacterial biomass and Collembola abundance to litter nutrient concentration was dependent on abiotic conditions. More specifically, the relationships between nutrients, especially calcium and magnesium, and bacterial biomass and Collembola abundance were less robust or disappeared under drier or warmer conditions. In conclusion, our findings underscore that ongoing climate change could affect soil organisms directly as well as indirectly, by altering their responses to litter nutrient concentrations. In addition, we found that nutrient‐rich habitats might be more affected than nutrient‐poor habitats by altered climatic conditions. [ABSTRACT FROM AUTHOR]

The breeding phenology of birds is often timed to coincide with a peak in food availability. However, the shortening of the vegetation period with increasing elevation may force bird species at high elevations to breed earlier in relation to optimal environmental conditions due to time constraints. We investigated differences in fledging dates in five Alpine woodland songbird species along an elevational gradient from 1500 to 2200 m in Switzerland. We estimated fledging dates from a nationwide citizen science bird monitoring dataset and used the date when the proportion of observations of 'fledged young' reached 50% among all observations indicating breeding behaviour. This measure had the advantage that we could estimate average timing of the broods across a wide geographic range and over many years without the need to search for individual nests. We then compared differences in timing of the broods with climatic conditions and larch budburst across different elevational bands. The daily mean air temperature of 10–15°C was reached 34–38 days later at 2200 m compared to 1500 m, which is a similar delay as found in previous reports on snow melt‐out date. The average delay in larch budburst was 19.2 days at 2200 m compared to 1500 m. In comparison, the average timing of the birds' broods was only 5.4 days later in coal tits and 0.5 days later in Alpine tits at 2200 compared to 1500 m (the two species for which we had the narrowest interval estimates). Also, the estimated delay at higher elevations in the broods of song thrushes, mistle thrushes and Eurasian chaffinches was relatively small. Rather than postponing breeding dates to better environmental conditions later in the season that would match the earlier conditions at low elevation, songbirds breeding at higher elevations may thus have evolved adaptations to cope with the harsher conditions. [ABSTRACT FROM AUTHOR]

The usability of polyvinyl chloride-based quaternary triethanol ammonium chloride anionite (PVC-TEAC) as a potential extractant for tungstate was investigated to recover tungstate from Gabal Qash Amir, Egypt, assaying 70.91% WO3. Structure elucidation for PVC-TEAC anionite was successfully carried out using several techniques. Experimental measurements, such as pH, agitation time, initial tungsten concentration, anionite dose, co-ions, temperature, and eluting agents, have been optimized. It was found that PVC-TEAC anionite has a maximum capacity of 63 mg per gram. From the distribution isotherm modeling, Langmuir's model fits the experimental results better than Freundlich's, with a theoretical value of 61.728 mg g-1. According to kinetic modeling, the first- and second-order modeling may be regarded as a mixed modeling for a successful adsorption system. Thermodynamic prospects reveal that the adsorption process was predicted as an exothermic, spontaneous, and preferable adsorption at low temperatures. Tungsten ions can be eluted from the loaded anionite, by 1M H2SO4 with a 97% efficiency rate. It was found that PVC-TEAC anionite reveals good separation factor (S.F.) towards most of co-ions. A successful Alkali fusion with NaOH flux followed by tungstate recovery by PVC-TEAC anionite is used to obtain a high-purity tungsten oxide concentrate (WO3), with a tungsten content of 78.3% and a purity of 98.75%. [ABSTRACT FROM AUTHOR]

The refractive index ${n_D}$ n D for the mixture (1,4-dioxane (1) + water (2)) was measured over the whole composition range at different temperatures and atmospheric pressure. From measured values of the refractive indices, the molar refraction ${R_m}$ R m , reduced molar free volumes ${{{V_m}} \over {{R_m}}}$ V m R m , molecular radii $r$ r and internal pressure, ${P_{int}}$ P int were calculated. On the other hand, some excess parameters were also deduced. The obtained results have been discussed and interpreted in terms of the type and nature of specific intermolecular interactions existed between the components. Furthermore, we have used nine mixing rules for refractive index proposed by different authors to calculate the refractive indices of the present mixture. A comparative study was carried out between the measured and calculated indices. The Redlich–Kister polynomial equation has been used to fit the presented excess parameters to derive the adjustable fitting coefficients and estimate the standard error values. [ABSTRACT FROM AUTHOR]

This article examines the effects of different storage conditions on selected physicochemical properties of three types of agro-biomass pellets: sunflower husks, wheat straw and hemp hurds, and wood pellets. The tests were carried out in a climatic chamber, which allows simulation of real storage conditions, i.e. conditions with high air humidity and variable (±) ambient air temperatures. The results showed higher degradability of agro-biomass pellets compared to woody biomass. The pellets degraded to a less extent at varying ± temperatures than at high humidity (90% RH). After complete moisture saturation, durability decreases for agro-pellets by an average of 9%, while after freezing and defreezing for sunflower husk pellets and woody pellets durability decreases by 2%, and for hemp hurd pellets by 11%. In contrast, strength-by-dropping index for agro-pellets decreased by 20% after being in the environment (30 °C and 90%RH) and 15% under varying temperature conditions. No change in the energy parameters of all pellets in the dry matter was noted. On the other hand, an increase in the moisture content of pellets when they are stored under different environmental conditions results in a decrease in calorific value. [ABSTRACT FROM AUTHOR]

Birds maintain some of the highest body temperatures among endothermic animals. Often deemed a selective advantage for heat tolerance, high body temperatures also limits birds' thermal safety margin before reaching lethal levels. Recent modelling suggests that sustained effort in Arctic birds might be restricted at mild air temperatures, which may require reductions in activity to avoid overheating, with expected negative impacts on reproductive performance. We measured within-individual changes in body temperature in calm birds and then in response to an experimental increase in activity in an outdoor captive population of Arctic, cold-specialised snow buntings (Plectrophenax nivalis), exposed to naturally varying air temperatures (− 15 to 36 °C). Calm buntings exhibited a modal body temperature range from 39.9 to 42.6 °C. However, we detected a significant increase in body temperature within minutes of shifting calm birds to active flight, with strong evidence for a positive effect of air temperature on body temperature (slope = 0.04 °C/ °C). Importantly, by an ambient temperature of 9 °C, flying buntings were already generating body temperatures ≥ 45 °C, approaching the upper thermal limits of organismal performance (45–47 °C). With known limited evaporative heat dissipation capacities in these birds, our results support the recent prediction that free-living buntings operating at maximal sustainable rates will increasingly need to rely on behavioural thermoregulatory strategies to regulate body temperature, to the detriment of nestling growth and survival. [ABSTRACT FROM AUTHOR]

Aim: Despite warming temperatures, some species are found persisting at the trailing edge of their distribution. Microclimates provided by complex topography are considered a key factor in these cases of range stationarity, buffering stress from exposure to warming and enabling persistence. However, for species with trailing‐edges located in human‐modified landscapes, refugial conditions provided by microclimates could be disrupted by human activities. Here, we aimed to understand the determinants of trailing‐edge occupancy for a small lagomorph found in rocky patches harbouring cool microclimates. Location: Hokkaido Island, Japan. Taxon: Northern pika (Ochotona hyperborea). Methods: We surveyed the occupancy of northern pikas across a wide elevational gradient (350–2200 m) for two consecutive summers. Ambient air and microhabitat (i.e. rock interstices) thermal conditions were measured to assess their relationship. We then analysed their effects on occupancy at two nested spatial scales: (1) whole‐distribution, and (2) at identified trailing‐edge sites where we explored the effects of microclimates and surrounding human activities (i.e. distance to nearest road and area of human land use such as plantation forests or agricultural fields). Results: Overall, rock interstices exhibited cooler conditions than ambient air with temperature differences of 1–2°C. The overall distribution of northern pikas was affected by both mean ambient temperature and microhabitat availability, with warmer (lower elevation) sites with less microhabitats corresponding to the trailing edge of its distribution. Interestingly, trailing edge occupancy patterns were best explained by the negative effect of surrounding human land despite the existence of suitable microclimates in the rocky patches. Main Conclusions: Our findings suggest that the local refugial conditions supported by cool microclimates are likely to be disrupted by the effects of human land alterations at the larger landscape scale. This result highlights the importance of considering the effects of human activities and landscape alteration for effective microrefugia conservation. [ABSTRACT FROM AUTHOR]

The present study focuses on characterizing the time–frequency aspects of seasonal temperatures in India by integrating the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) algorithm with the Hilbert–Huang transform (HHT) decomposition method. The investigation also explores the connections between maximum temperature (Tmax) and minimum temperature (Tmin) with global climate oscillations, such as the El Nino Southern Oscillation (ENSO), Sunspot Number (SN), and Pacific Decadal Oscillations (PDO). The findings indicate that intra and inter-decadal modes play a pivotal role in influencing temperature series across various seasons, with notable changes observed in the amplitudes of inter-decadal modes for seasonal Tmin and Tmax. The analysis of intrinsic mode functions (IMFs) reveals that IMF2 closely align to ENSO with a periodicity of 5–7 years, IMF3 to the sunspot cycle with a frequency of approximately 11 years, and IMF5 to PDO with a long periodicity exceeding 60 years. The association between the IMF components of Tmin and Tmax temperature series and the three climate indices is most evident for low-frequency modes, demonstrating a consistent evolution of trend components. [ABSTRACT FROM AUTHOR]

This study introduced the application of concepts and methods from extreme value theory (EVT) to estimate the probability that daily minimum temperatures exceed springtime critical temperature thresholds for Pinot noir buds and young shoots as a function of springtime phenology. The springtime frost risk estimates were computed spatially for Pinot noir throughout the Willamette Valley (WV) American Viticultural Area (AVA) using a gridded dataset of historical daily minimum surface air temperature data. EVT-based springtime frost risk maps can inform vineyard-management operations by identifying those locations throughout a wine region with a low risk for any cold injury where remedial action is likely not necessary when there is a forecasted frost event. Frost risk estimates were computed for 1991–2021 and 1991–2022 to examine a potentially changed risk profile for springtime frost events throughout the WV AVA due to the April 2022 advective frost event. The April 2022 advective frost event influenced the risk profile throughout the AVA such that an event of its magnitude is now modelled to occur more frequently. The EVT-based risk analysis can be readily updated each year as new data become available. While spatially varying budbreak calculations facilitated computation of the spring frost risk estimates, the EVT approach profiled in this study does not necessarily depend on potentially uncertain predetermined budbreak date estimates. Gridded maps of extreme daily minimum temperature exceedances, reclassified relative to the springtime phenology critical temperature thresholds for Pinot noir, were readily combined with a ripening potential map to identify optimal areas for vineyard site selection throughout the WV AVA. When simultaneously evaluating Pinot noir ripening potential with springtime frost risk using historical data, the limiting factor for vineyard site selection throughout the WV AVA was frost risk, not ripening potential. The study approach is also applicable for other winegrape-growing regions, assessments of winter freeze risk and summertime heatwaves, and with non-gridded observed temperature datasets. [ABSTRACT FROM AUTHOR]

Agricultural sustainability is dependent on the ability to predict crop yield, which is vital for farmers, consumers, and researchers. Most of the works used the amount of rainfall, average monthly temperature, relative humidity, etc. as inputs. In this paper, an attempt was made to predict the yield of the citrus crop (Washington Navel orange, Valencia orange, Murcott mandarin, Fremont mandarin, and Bearss Seedless lime) using weather factors and the accumulated heat units. These variables were used as input parameters in an artificial neural network (ANN) model. The necessary information was gathered during the growing seasons between 2010/2011 and 2021/2022 under Egyptian conditions. Weather factors were daily precipitation, yearly average air temperature, and yearly average of air relative humidity. A base air temperature of 13.0 °C was used to determine the accumulated heat units. The heat use efficiency (HUE) for cultivars was determined. The Bearss Seedless lime had the lowest HUE of 9.5 kg/ha °C day, while the Washington Navel orange had the highest HUE of 20.2 kg/ha °C day. The predictive performance of the ANN model with a structure of 9-20-1 with the backpropagation was evaluated using standard statistical measures. The actual and estimated yields from the ANN model were compared using a testing dataset, resulting in a value of RMSE, MAE, and MAPE of 2.80 t/ha, 2.58 t/ha, and 5.41%, respectively. The performance of the ANN model in the training phase was compared to multiple linear regression (MLR) models using values of R2; for MLR models for all cultivars, R2 ranged between 0.151 and 0.844, while the R2 value for the ANN was 0.87. Moreover, the ANN model gave the best performance criteria for evaluation of citrus yield prediction with a high R2, low root mean squared error, and low mean absolute error compared to the performance criteria of data mining algorithms such as K-nearest neighbor (KNN), KStar, and support vector regression. These encouraging outcomes show how the current ANN model can be used to estimate fruit yields, including citrus fruits and other types of fruit. The novelty of the proposed ANN model lies in the combination of weather parameters and accumulated heat units for accurate citrus yield prediction, specifically tailored for Egyptian regional citrus crops. Furthermore, especially in low- to middle-income countries such as Egypt, the findings of this study can greatly enhance the reliance on statistics when making decisions regarding agriculture and climate change. The citrus industry can benefit greatly from these discoveries, which can help with optimization, harvest planning, and postharvest logistics. We recommended furthering proving the robustness and generalization ability of the results in this study by adding more data points. [ABSTRACT FROM AUTHOR]

Large quantities of pumpkins, rich in valuable nutrients, are lost due to superficial imperfections or size variations. This study explores a solution: transforming this unused resource into a highly functional food ingredient-pumpkin powder obtained from dehydration. This study emphasizes the importance of a detailed particle-level mathematical model in dehydrator design and operation, particularly for drying conditions using air at temperatures between 333 K and 353 K. The model investigates the effect of sample geometry on the moisture reduction rate and the product quality. Here, a model considers mass and energy transport, including the shrinkage ratio of the samples. The results effectively demonstrate the deformation, moisture content, and temperature evolution within the samples throughout the drying process. The findings reveal that both the drying temperature and initial sample geometry significantly influence the moisture loss rate, the final product texture, and the powder's absorption capacity. Notably, the nutritional composition (except for lipids) remains largely unaffected by the drying process. Additionally, the bulk and compacted densities of the powders decrease with increasing temperature. These insights not only illuminate the performance of the drying process but also provide valuable knowledge regarding the dehydrated product's technological behavior and potential functionalities within various food applications. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs), including all 209 congeners, are designated as persistent organic pollutants (POPs) due to their high toxicity and bioaccumulation in human bodies and the ecosystem. The need for PCB remediation still remains long after their production ban. In this study, a catalytic hydro-dechlorination (HDC) method was employed to dechlorinate 2,4,4'-trichlorobiphenyl (PCB 28), a congener found ubiquitously in multiple environmental media. The HDC of PCB 28 was experimentally studied at mild temperatures viz. ~20, 50, and ~77°C and atmospheric pressure. Et3N (triethylamine) was added as a co-catalyst. The dechlorination rates increased with temperature as well as Et3N dosage, and the HDC pathway was hypothesized based on the product and intermediates observed. The less chlorinated intermediates suggested that the position of the chlorine strongly impacted HDC rates, and the preference of HDC at para positions can be orders of magnitudes higher than the ortho. The activation energy was estimated in the range of 12.4–13.9 kJ/mole, indicating a diffusion-controlled HDC system. Implications: The remediation need for polychlorinated biphenyls (PCBs) still remains long after their production ban around the world. The development of low-cost methods is highly desirable, especially for developing countries, in response to the Stockholm Convention. In this study, the dechorination of a ubiquitously present PCB congener was studied using a catalytic hydro-dechlorination (HDC) method in low temperatures up to ~77°C and was able to achieve near 100% dechlorination in 6 hr. Results indicated that the HDC process can be performed under mild temperatures and atmospheric conditions and can be a potential solution to real world PCB contamination issues. [ABSTRACT FROM AUTHOR]

Background and Aim: In Central Vietnam, Anopheles dirus and Anopheles minimus are the primary malaria vector species. These Anopheles spp.' distribution and prevalence are determined by environmental, climatic, and socioeconomic conditions. This study aimed to predict the potential distribution of these two Anopheles spp. in this region. Materials and Methods: This study was conducted in 15 Central Vietnamese provinces. From 2014 to 2018, we utilized An. dirus and An. minimus presence records. Proxy data from the Google Earth Engine platform for the study area, encompassing environmental, climatic, and socioeconomic factors. MaxEnt software predicted the potential environmental, climatic, and socioeconomic suitability of these two Anopheles spp. in Central Vietnam. Results: The test area under the curve values for An. dirus and An. minimus MaxEnt models averaged 0.801 and 0.806, respectively, showing excellent performance. Minimum air temperature had the greatest impact on the distribution of both species. A negative correlation between precipitation and normalized difference water index influences the occurrence of An. dirus. In the temperature range of 13-19.5°C, An. minimus is most likely to be present, with nighttime light detrimentally influencing its distribution. The Central Highlands region is inhabited by both species, with some presence in North-Central and South-Central Coastal areas. Conclusion: The importance of temperature in determining the presence of both species is emphasized by our findings, with subtle differences in the temperature-related factors shaping their distributions. The results highlight the need for focused malaria vector control and surveillance initiatives in the study area. [ABSTRACT FROM AUTHOR]

Here, we passivated the interfacial defects of ZnO/CsPbBr3 by inserting a NaSCN layer between the ZnO electron transport layer and the CsPbBr3 layer to improve the photoelectric conversion efficiency of ZnO/CsPbBr3/Carbon structure solar cell. The addition of the NaSCN optimized the morphology of the ZnO surfaces to decrease effectively the roughness. Furthermore, The passivated ZnO electron transport layer improved the deposition quality of CsPbBr3 films, which reduced the defects at the interface between the ZnO electron transport layer and CsPbBr3 layer, suppressing non-radiative recombination to enhance device photovoltaic performance. Synergistic passivation of SCN− and Na+ ions plays an important role in obtaining high-quality CsPbBr3 films for boosting the power conversion efficiency (PCE) of the device. Moreover, the passivated solar cells had longer stability than the pristine ones after being placed for 1000 h in the air and at room temperature. [ABSTRACT FROM AUTHOR]

Here we present a new eastern Baltic Chironomidae training set (TS) containing 35 sites that was collected and merged with neighbouring published Finnish (82 lakes) and northern part of the Polish (nine lakes) TSs. Chironomidae, non‐biting midges, are known to be strongly responsive to the July air temperature and are widely used to infer palaeotemperature. Several modern analogue‐based TSs necessary for calibrating the relationships between mean July air temperature (MJAT) and chironomids are available for Europe. However, none of these is representative of the transitional climate typical for eastern Baltic (Estonia, Latvia, Lithuania). The Finno–Baltic–Polish TS contains 121 sites and covers a geographically continuous 70–50°N latitudinal and 7 °C (12.1–19.2 °C) MJAT gradient. Canonical correspondence analysis revealed that, among the tested environmental variables (pH, water depth, dissolved oxygen, MJAT), the MJAT explains the highest amount of variation, both for the eastern Baltic separately and the Finno–Baltic–Polish TSs. The weighted averaging–partial least squares‐based cross‐validation test reveals that the Finno–Baltic–Polish TS has a low root mean square error of prediction (0.7 °C) confirming the high reliability of the TS. The temperature optima of the taxa included in the new Finno–Baltic–Polish TS and widely used Swiss–Norwegian TS were examined. The observed dissimilarities can be attributed to the differences in the temperature ranges represented by the TS, the taxonomic identification level, the general cosmopolitan taxa distribution patterns and the influence of TS‐specific geographic position, climatic or environmental conditions. The new Finno–Baltic–Polish TS adds to the knowledge on the modern distribution of Chironomidae taxa and widens the geographical area of reliable Chironomid‐based MJAT reconstructions into the eastern European lowland. [ABSTRACT FROM AUTHOR]

Irrigation is becoming increasingly common in agriculture and is essential to meet the growing demand for food. Studies of the impact of irrigated areas on local meteorology reveal a strong influence on near‐surface conditions, although the extent of this influence varies considerably between locations. In addition, though theoretical evidence suggests that irrigation can create breeze‐like atmospheric boundary‐layer circulations, observational evidence is still lacking. This study investigates the effects of irrigation on the surface and atmospheric boundary layer in the Ebro basin, an intensively irrigated area with a semi‐arid climate in northeastern Spain. Observational data from the international field campaign Land Surface Interactions with the Atmosphere over the Iberian Semi‐arid Environment are analysed together with coupled surface–atmosphere model output to better understand and quantify the impact of irrigation on the lower atmosphere. A simple parametrization of irrigation is shown to improve the accuracy of the model. Results demonstrate that irrigation increases the average latent heat flux by over 200 W·$$ \cdotp $$m −2$$ {}^{-2} $$, reduces air temperature by 4.7°C, and increases specific humidity by 50% at 2 m during the day over the irrigated region of the domain. Moreover, irrigation limits convection and strongly stabilizes the atmospheric boundary layer. Notably, the study provides evidence for an irrigation‐induced breeze from the irrigated area to the semi‐arid area. These findings highlight the importance of considering irrigation in numerical models for weather forecasting, climate modelling and sustainable agricultural planning. [ABSTRACT FROM AUTHOR]

The temperature sensitivities of photosynthesis and respiration remain a key uncertainty in predicting how forests will respond to climate warming. We grew seedlings of four temperate tree species, including Betula platyphylla , Fraxinus mandshurica , Juglans mandshurica and Tilia amurensis , at three temperature regimes (ambient, +2 °C, and +4 °C in daytime air temperature). We investigated net photosynthesis (Anet25), maximum rate of RuBP-carboxylation (Vcmax25) and RuBP-regeneration (Jmax25), stomatal conductance (gs25), mesophyll conductance (gm25), and leaf respiration (Rleaf) in dark (Rdark25) and in light (Rlight25) at 25 °C in all species. Additionally, we examined the temperature sensitivities of Anet, Vcmax, Jmax, Rdark and Rlight in F. mandshurica. Our findings showed that the warming-induced decreases in Anet25, Vcmax25 and Jmax25 were more prevalent in the late-successional species T. amurensis. Warming had negative impacts on gs25 in all species. Overall, Anet25 was positively correlated with Vcmax25 and Jmax25 across all growth temperatures. However, a positive correlation between Anet25 and gs25 was observed only under warming conditions, and gs25 was negatively associated with vapor pressure deficit. This implies that the vapor pressure deficit-induced decrease in gs25 was responsible for the decline in Anet25 at higher temperatures. The optimum temperature of Anet in F. mandshurica increased by 0.59 °C per 1.0 °C rise in growth temperature. While +2 °C elevated the thermal optima of Jmax, it did not affect the other temperature sensitivity parameters of Vcmax and Jmax. Rdark25 was not affected by warming in any species, and Rlight25 was stimulated in T. amurensis. The temperature response curves of Rdark and Rlight in F. mandshurica were not altered by warming, implying a lack of thermal acclimation. The ratios of Rdark25 and Rlight25 to Anet25 and Vcmax25 in T. amurensis increased with warming. These results suggest that Anet and Rleaf did not acclimate to warming synchronously in these temperate tree species. [ABSTRACT FROM AUTHOR]

Measuring and modelling manure temperatures are crucial for estimating greenhouse gas emissions from liquid manure storage. The manure temperature was recorded at various depths in two swine slurry storage tanks situated in Vallentuna (VA) and Örsundsbro (OR) in Sweden. These data were used to assess the effectiveness of a revised mechanistic model for estimating manure temperatures, which incorporates the effects of wall shading, snow cover, and manure input mixing. The average manure temperatures were higher than air temperatures in the summer and fall. This indicated that using air temperature would result in an underestimation of methane emissions when applying the 2019 IPCC Refinement methodology. The revised model estimated manure temperatures for spring, summer, fall, and winter as 4.8, 16.1, 7.8, and 2.6 °C at the VA tank and 11.6, 17.1, 9.5, and 3.6 °C at the OR tank. The root mean square errors between daily simulated and observed temperatures in the summer decreased in both tanks due to incorporating shadow effect into the revised model. Fall estimates did not improve, possibly because of uncertainties from slurry removal and higher precipitation inputs. Sensitivity analysis indicated that solar radiative heat input was reduced with higher tank walls and smaller tank diameters when applying the revised model. Wall shading may influence manure temperatures in tanks with small diameters at high-latitude locations. This study offers insights into understanding the relationship between manure temperatures and its thermal balance influenced by latitude, storage design, snow cover and mixing, and its implications for accurately estimating methane emissions. [Display omitted] • Including shading, snow cover and mixing effects improved manure temperature predictions. • Solar radiative input is susceptible to manure storage wall height and diameter. • The revised model improved the accuracy of summer manure temperature estimates. • Fall manure temperature estimates remain unreliable due to uncertainty in slurry volume. [ABSTRACT FROM AUTHOR]

The stable carbon isotope composition of total organic matter (δ13Corg) has been utilized in aeolian sediments, serving as an indicator for reconstructing terrestrial paleoenvironments. The Qinghai Lake (QHL) Basin is a climate-sensitive region of significant importance in paleoclimatic reconstruction. However, the reconstructed climatic variations based on δ13Corg in aeolian sediments in the QHL Basin in the northeastern Qinghai-Tibet Plateau (QTP) are lacking, and their paleoclimatic significance remains poorly understood. By conducting δ13Corg measurements on the Niaodao (ND) aeolian profile near QHL, we reconstructed the paleoclimate changes of 11 ka–present. The variation range of the δ13Corg values in the ND profile indicated the terrestrial ecosystems were not the sole contributor to lacustrine organic matter. The δ13Corg values are an indicator of historical temperature changes in the study area, exhibiting similar trends with the reconstruction of Chinese summer temperatures, East Asian air temperature, global temperature, and Northern Hemisphere summer insolation at 37° N. The temperature increased with high frequency and amplitude oscillations, with strong aeolian activity and low total organic carbon accumulation during the Early Holocene. The temperature was maintained at a high and stable level, with the weakest aeolian activity and intensified pedogenesis during the Middle Holocene. The temperature decreased at a high rate, with renewed aeolian activity and weak pedogenesis during the Late Holocene. [ABSTRACT FROM AUTHOR]

A metrological field intercomparison of thermometer radiation shields in the Arctic was conducted with the aim of obtaining information to increase the worldwide comparability of air temperature measurements. Air temperature measurements are performed by different combinations of thermometers and shields. The response of each system (thermometer + shield) to local meteorological conditions depends on the system itself, limiting the comparability of air temperature measurements. Ten different models of radiation shields were included in the intercomparison, involving two campaigns: (1) the laboratory campaign, where all the instrumentation was calibrated just before and just after the field campaign, and (2) the field campaign that lasted 14 months where 41 thermometers were sampled every 2 min. All the delivered data were subjected to quality control to assure the robustness of the conclusions. A reference shield was defined, and the other shields were compared to the reference one for the conditions where maximum divergences were expected, solar irradiance being the highest impact factor. A maximum divergence value of 1.29 °C was derived for one of the shields and, for all the shields, the difference from the reference one decreases with wind speed. Finally, the uncertainties associated with the shields intercomparison were calculated. [ABSTRACT FROM AUTHOR]

Climate change causes a global rise in mean air temperature and an increased frequency of temperature extremes. Recent studies link sharp temperature changes between consecutive days to increased mortality, reduced economic growth, and negative effects on ecosystems. This study assesses the variability of the daily maximum air temperature between two consecutive days (i.e., temperature volatility) across Germany from 1990 to 2022. Using observation-based raster data of maximum daily temperature at 0.1° × 0.1° spatial resolution, we assess temperature volatility regarding: (1) magnitude, (2) seasonality, (3) directionality (day-to-day warming vs. cooling), and (4) trends. Further, we analyse land cover changes during the period and examine their correlation to extreme temperature volatility (Tve). The results show that Tve mostly occurred during spring and summer. The magnitude of Tve increased with distance to the coast north-west to south during all seasons and was highest during spring and summer (>10 °C). Overall, Tve was particularly associated with day-to-day cooling (in spring, summer, autumn), while in winter, >60% of days were associated with warming in north and central Germany. Less than 12% of Germany showed significant trends in median Tve associated with warming over the period. Significant trends included increases (>0.26 °C/year) and decreases (−0.09 °C/year) in extreme day-to-day warming during autumn and winter in northeastern Germany. In spring, the majority (>60%) of southern areas showed significant positive trends (up to 0.16 °C/year) in Tve associated with day-to-day cooling. During winter, summer, and autumn, trends in extreme day-to-day cooling were insignificant in over 80% of Germany. Within all land cover types, Tve predominantly varied between 6 °C and 9 °C. Changes in land cover, especially transforming coniferous forests for agricultural purposes, were accompanied by increasing Tve up to 0.49 °C. Understanding rapid temperature changes is crucial for climate change mitigation strategies and limiting the impacts on human health and on the environment. [ABSTRACT FROM AUTHOR]

Several configurations of the Canadian Precipitation Analysis system (CaPA) currently produce precipitation analyses at Environment and Climate Change Canada (ECCC). To improve CaPA's performance during the winter season, the impact of assimilating the IMERG V06 product (IMERG: Integrated Multi-satellitE Retrievals for GPM—Global Precipitation Measurement mission) into CaPA is examined in this study. Tests are conducted with CaPA's 10 km deterministic version, evaluated over Canada and the northern part of the United States (USA). Maps from a case study show that IMERG plays a contradictory role in the production of CaPA's precipitation analyses for a synoptic-scale winter storm over North America's eastern coast. While its contribution appears to be physically correct over southern portions of the meteorological system, and early in its intensification phase, IMERG displays unrealistic spatial structures over land later in the system's life cycle when it is located over northern (colder) areas. Objective evaluation of CaPA's analyses when IMERG is assimilated without any restrictions shows an overall decrease in precipitation, which has a mixed effect (positive and negative) on the bias indicators. But IMERG's influence on the Equitable Threat Score (ETS), a measure of CaPA's analyses accuracy, is clearly negative. Using IMERG's quality index (QI) to filter out areas where it is less accurate improves CaPA's objective evaluation, leading to better ETS versus the control experiment in which no IMERG data are assimilated. Several diagnostics provide insight into the nature of IMERG's contribution to CaPA. For the most successful configuration, with a QI threshold of 0.3, IMERG's impact is mostly found in the warmer parts of the domain, i.e., in northern US states and in British Columbia. Spatial means of the temporal sums of absolute differences between CaPA's analyses with and without IMERG indicate that this product also contributes meaningfully over land areas covered by snow, and areas where air temperature is below −2 °C (where precipitation is assumed to be in solid phase). [ABSTRACT FROM AUTHOR]

The commonly used reference atmospheric profiles for the validation of retrieved atmospheric profiles for microwave sounders have bias compared with real atmospheric profile values, which is detrimental to the validation of the retrieval. Microwave sounder observations are the direct measurements of microwave radiation in atmospheric conditions and are a true representation of the status of the atmosphere. This paper proposed a validation method for the retrieved atmospheric temperature and atmospheric humidity profiles of the satellite-based microwave sounder using its own in-orbit observations. The validation experiments are performed both for the retrievals of the microwave temperature sounder-II (Xi'an Branch, China Academy of Space Technology, Xi'an, China. MWTS-II) and the microwave humidity and temperature sounder (National Space Science Center, Chinese Academy of Sciences, Beijing, China. MWHTS). The validation results show that the retrieved temperature profiles of MWTS-II have higher accuracy compared to the temperature profiles of ERA5 in the atmospheric pressure range of 3–30 hPa, and the accuracy of the rest of the pressure range is comparable between the profiles of ERA5 and the retrieved profiles. And the retrieved temperature profiles of MWHTS have higher accuracy compared to the temperature profiles of ERA5 in the atmospheric pressure level around 50 hPa and lower accuracy in the rest of the pressure levels. In addition, the retrieved humidity profiles of MWHTS have higher accuracy compared to the humidity profiles of ERA5 in the atmospheric pressure range of 350–925 hPa. The proposed validation method for the retrieved atmospheric temperature and atmospheric humidity profiles of MWHTS using its own observations is promising for improving the feasibility and reliability of the validation, and can be a good reference for the application of the satellite in-orbit observations and the optimization of the microwave sounders. [ABSTRACT FROM AUTHOR]

Accurate air temperature measurements are essential in eddy covariance systems, not only for determining sensible heat flux but also for applying density effect corrections (DECs) to water vapor and CO2 fluxes. However, the influence of wind-induced vibrations of mounting structures on temperature fluctuations remains a subject of investigation. This study examines 30 min average temperature variances and fluxes using eddy covariance systems, combining Campbell Scientific sonic anemometers with closely co-located fine-wire thermocouples alongside LI-COR CO2 – H2O gas analyzers at multiple heights above a sagebrush ecosystem. The variances of sonic temperature after humidity corrections (Ts) and sensible heat fluxes derived from Ts are underestimated (e.g., by approximately 5 % for temperature variances and 4 % for sensible heat fluxes at 40.2 m , respectively) as compared with those measured by a fine-wire thermocouple (Tc). Spectral analysis illustrates that these underestimated variances and fluxes are caused by the lower energy levels in the Ts spectra than the Tc spectra in the low-frequency range (natural frequency < 0.02 Hz). These underestimated Ts spectra in the low-frequency range become more pronounced with increasing wind speeds, especially when wind speed exceeds 10 ms-1. Moreover, the underestimated temperature variances and fluxes cause overestimated water vapor and CO2 fluxes through DEC. Our analysis suggests that these underestimations when using Ts are likely due to wind-induced vibrations affecting the tower and mounting arms, altering the time of flight of ultrasonic signals along three sonic measurement paths. This study underscores the importance of further investigations to develop corrections for these errors. [ABSTRACT FROM AUTHOR]

Accurate and continuous estimates of the thermodynamic structure of the lower atmosphere are highly beneficial to meteorological process understanding and its applications, such as weather forecasting. In this study, the Tropospheric Remotely Observed Profiling via Optimal Estimation (TROPoe) physical retrieval is used to retrieve temperature and humidity profiles from various combinations of input data collected by passive and active remote sensing instruments, in situ surface platforms, and numerical weather prediction models. Among the employed instruments are microwave radiometers (MWRs), infrared spectrometers (IRSs), radio acoustic sounding systems (RASSs), ceilometers, and surface sensors. TROPoe uses brightness temperatures and/or radiances from MWRs and IRSs, as well as other observational inputs (virtual temperature from the RASS, cloud-base height from the ceilometer, pressure, temperature, and humidity from the surface sensors) in a physical iterative retrieval approach. This starts from a climatologically reasonable profile of temperature and water vapor, with the radiative transfer model iteratively adjusting the assumed temperature and humidity profiles until the derived brightness temperatures and radiances match those observed by the MWR and/or IRS instruments within a specified uncertainty, as well as within the uncertainties of the other observations, if used as input. In this study, due to the uniqueness of the dataset that includes all the abovementioned sensors, TROPoe is tested with different observational input combinations, some of which also include information higher than 4 km above ground level (a.g.l.) from the operational Rapid Refresh numerical weather prediction model. These temperature and humidity retrievals are assessed against independent collocated radiosonde profiles under non-cloudy conditions to assess the sensitivity of the TROPoe retrievals to different input combinations. [ABSTRACT FROM AUTHOR]

We present chironomid-based reconstructions of mean July air temperature changes over the last 2000 years from Lake Latoriței (1530 m a.s.l.) in the Southern Carpathians. A multi-proxy analysis was performed along a 58 cm long sediment core and two training sets were used for quantitative July air temperature reconstructions: the Eastern-European (EE, 212 lakes) and the Finnish-Polish-Carpathian (FPC, 273 lakes). The transfer functions had a coefficient of determination (r 2) 0.88 and 0.91 with a root mean squared error of prediction (RMSEP) 0.88°C and 1.02°C. Despite possible biases resulting from methodological problems and the ecological complexity of the chironomid response to both climatic and environmental changes, the agreement of the temperature reconstruction of Lake Latoriței with other alpine records suggests that the transfer function successfully reconstructed past summer temperatures between 750 and 1830 CE. Biases in the temperature reconstruction in the period before 750 and after 1830 CE were likely caused by increased abundance of rheophilic and semi-terrestrial chironomid species related to increased inflow activity before 750 CE and local land use changes after 1830 CE, which was also indicated by increasing deforestation and increasing lake productivity in the pollen and diatom records. Our results suggest that the region experienced a warm period between 750 and 1360 CE, and a cold period between 1360 and 1600 CE followed by fluctuating summer temperatures until 1830 CE. These events were associated with the so-called 'Mediaeval Warm Period' (MWP) and the 'Little Ice Age' (LIA), respectively. The inference models reconstructed a decrease in July air temperatures by 0.7°C–1.1°C during the LIA relative to the warmer MWP. We also demonstrated that the FPC training set gives better results, supporting that local/continental training sets are efficient to detect weak amplitude summer temperature changes in the Late-Holocene. [ABSTRACT FROM AUTHOR]

Many glaciers on the Antarctic Peninsula have retreated and accelerated in recent decades. Here we show that there has been a widespread, quasi-synchronous, and sustained increase in grounding line discharge from glaciers on the west coast of the Antarctic Peninsula since 2018. Overall, the west Antarctic Peninsula discharge trends increased by over a factor of 3, from 50 Mtyr-2 during 2017 to 2020 up to 160 Mtyr-2 in the years following, leading to a 7.4 % increase in grounding line discharge since 2017. The acceleration in discharge was concentrated at glaciers connected to deep, cross-shelf troughs hosting warm-ocean waters, and the acceleration occurred during a period of anomalously high subsurface water temperatures on the continental shelf. Given that many of the affected glaciers have retreated over the past several decades in response to ocean warming, thereby highlighting their sensitivity to ocean forcing, we argue that the recent period of anomalously warm water was likely a key driver of the observed acceleration. However, the acceleration also occurred during a time of anomalously high atmospheric temperatures and glacier surface runoff, which could have contributed to speed-up by directly increasing basal water pressure and, by invigorating near-glacier ocean circulation, increasing submarine melt rates. The spatial pattern of glacier acceleration therefore provides an indication of glaciers that are exposed to warm-ocean water at depth and/or have active surface-to-bed hydrological connections; however, many stages in the chain of events leading to glacier acceleration, and how that response is affected by glacier-specific factors, remain insufficiently understood. Both atmospheric and ocean temperatures in this region and its surroundings are likely to increase further in the coming decades; therefore, there is a pressing need to improve our understanding of recent changes in Antarctic Peninsula glacier dynamics in response atmospheric and oceanic changes in order to improve projections of their behaviour over the coming century. [ABSTRACT FROM AUTHOR]

This article undertakes both theoretical and experimental investigation on the heat and mass transfer properties of wet air and solution (configured sodium hydroxide solution with the concentration of 2%) on the surface of corrugated packings under reduced ambient pressure conditions. Theoretical analysis reveals that a decreased atmospheric pressure environment is conducive to amplifying mass transfer potential difference. However, it concurrently mitigates the maximum possible mass of water vapor per unit volume of air. Subsequently, experiments were carried out under the following conditions: vacuum degree-0 ~ 40 kPa, inlet air velocity-0.8 ~ 1.6 m/s, inlet air temperature-12.0 ~ 22.0 °C, and inlet air relative humidity-50.0 ~ 95.0%. The experimental outcomes indicate that heat transfer coefficient is predominantly influenced by inlet air velocity and vacuum degree. An enhancement of inlet air velocity or a reduction of vacuum degree leads to a corresponding increase of heat transfer coefficient. Under consistent conditions for other parameters, as vacuum degree ascends, moisture absorption rate and efficiency exhibit a steady growth, albeit with a diminishing rate of increment. Under constant inlet air velocity and relative humidity conditions, mass transfer coefficient initially experiences an upsurge as vacuum degree rises, but eventually undergoes a decline. At a fixed inlet air temperature, mass transfer coefficient behaves differently depending on air temperature. It demonstrates a gradual decrease under cooler air temperatures as vacuum degree rises, whereas under warmer air temperatures, it initially increases and then decreases. The analysis reveals that elevating vacuum degree indeed augments mass transfer capability between wet air and solution. However, there exists an upper limit to this enhancement, dictated by the maximum amount of water vapor that wet air can bear upon reaching saturation. [ABSTRACT FROM AUTHOR]

Winter cold wave adaptation strategies in hot climates due to climate change didn't receive the deserved attention from previous studies. Therefore, this study comprehensively investigates the impact of various windbreak parameters on mitigating winter cold stress in hot steppe-arid climate. A microclimate model for a residential campus was built and validated through on-site measurement on a typical winter day to assess thirty-two scenarios for tree characteristics and spatial configuration windbreak parameters based on PET, wind speed, and Air Temperature (AT). Moreover, four configurations, that had best results on mitigating cold stress in winter, were tested during typical summer conditions to couple the assessment of cold and hot seasons. Additionally, environmental analysis for all scenarios was conducted. The results revealed that the most effective parameters for mitigating cold stress are tree distribution, Leaf Area Density (LAD), row number, spacing, and shape. Double rows of high LAD and medium height trees with small spacing yielded the best cold stress mitigation effect. Furthermore, the windbreak reduced the cold stress in the morning and night by 19.31% and 18.06%, respectively. It reduced AT and wind speed at night by 0.79 °C and 2.56 m/s, respectively. During summer, very hot PET area was reduced by 21.79% and 19.5% at 12:00 and 15:00, respectively. [ABSTRACT FROM AUTHOR]

In Indian cities where streets are the only affordable outdoor public space, pedestrians are always exposed to extreme heat related health risk. However, it's a challenge to reduce heat stress in existing streets characterized by asymmetrical urban configuration. Integrating vegetation without reconstituting the original orientation and geometry is one of the feasible ways to alleviate stress. Therefore, current study focuses to analyse the heat stress reduction potential of urban greenery strategy in asymmetrical urban configuration from spatiotemporal perspective. It initiates with the selection of commercial streets in extreme hot climate with an on-site measurement of its climatic and morphological attributes. Furthermore, it leads to the classification and prioritizing of street's sections linked to hot-spots determined by varied sky view factor and asymmetrical aspect ratio. Finally, an Envi-Met model with iterated scenarios at the building and street levels is developed, incorporating three strategies (trees, grass, green-walls). The impact of heat related health risk is quantified using a thermal index Universal Thermal Climate Index along with air temperature and mean radiant temperature. The results suggested that due to asymmetricity a fixed strategy would not be applicable across the street. The highest reduction was observed by trees in asymmetrical sections while lowest was recorded by green-wall. However, it would be worthwhile to adopt green-wall along with dense tree's (leaf area density, 0.3) in order to reduce the heat stress in deeper sections. The evidence-based integration of Urban greenery can assist planners and designers in mitigating extreme heat stress in similar complex urban environment. [ABSTRACT FROM AUTHOR]

We installed a meteorological recording system at Badwater (elev. −75 m), the lowest point in Death Valley, California and recorded data over the period 1998–2019. A second station (the Outhouse Station) was established nearby from 2014 to 2019. Here, we report on and publicly archive the data from these two stations. Of interest was the comparison between two air temperature measurements at the Badwater Station, the first with an aspirated platinum resistance temperature device and the second with a thermistor probe in a passive sun shield. During the hottest periods of the summer when temperatures were typically between 30°C at night and 50°C daily peak, the passively shielded sensor indicated up to 0.5°C warmer than the aspirated temperature sensor due to radiative effects. The data suggest a correction for radiative heating of (T–35)/30, for T > 35°C, where, T, is the uncorrected temperature reading of a passively shielded sensor subtracted after any calibration at lower temperatures. Our station was the first precision temperature measurements at Badwater. A longer record exists for the reporting station near the visitor's centre at the Furnace Creek. The summer temperature maxima at the Badwater site correlate well with the values the same day from the Furnace Creek site. The daily maximum temperatures in winter at the Badwater site appear to be about 1°C lower than at the Furnace Creek site. The largest differences are in the minimum temperatures for which the Badwater site averages about 2–3°C warmer than the Furnace Creek site. [ABSTRACT FROM AUTHOR]

Taklamakan Desert (TD) has been characterized by numerous heatwaves and dust storms, leading to negative effects on societies and ecosystems at regional and global scales. However, the association between heatwaves and dust storms is poorly known. In this study, we describe the association between heatwaves and dust events and propose a mechanism for such compound events in the TD. The results show that, from 1993 to 2022, the frequency and intensity of heatwaves in the TD have increased at a rate of 0.21 days year−1 and 0.02°C year−1, respectively. More than 40% of heatwaves existed with dust events, which significantly lagged behind heatwaves. Mechanically, the higher the air temperature, the hotter and drier the soil, leading to more dust emissions in the TD. In high-occurrence heatwave years, a large-scale wave train of "cyclone-anticyclone-cyclone" in the northwest-southeast direction was found, with the anticyclone of which hovered over the TD region. The anomalous anticyclones favored the formation and maintenance of heatwaves, and subsequent anomalous cyclones in the wave train triggered strong dust events followed by heatwaves. With climate warming, the compound events of heatwave and dust storm are becoming bigger hazards threatening the socioeconomic and ecological security in the TD, the profound study of which is critical to understanding regional extreme responses. [ABSTRACT FROM AUTHOR]

Drinking water is scarce in many regions of the world despite the omnipresence of water in the form of vapour in large quantities in the atmosphere. Currently, majority of water harvesters use vapour compression refrigeration cycle, which is inefficient. Thus, to reduce electrical energy consumption, the idea proposed in this study is to use a sorption-based atmospheric water generator (AWG) which works on low-grade heat energy. The key component of the proposed AWG is a desiccant-coated fin tube heat exchanger (DCFTHX) which humidifies and heats the air to such an extent that the vapour present in the air can be condensed by simply bringing it in thermal contact with a surface at atmospheric temperature. Thermodynamic modelling of the proposed AWG is first presented, followed by a systematic study under various weather conditions ranging from temperatures of 6 °C to 40 °C and specific humidity from 0.004 to 0.22 kg kg d.a.−1. Results indicate that water can be produced even for specific humidity of 4 kg kg d.a.−1 (near zero dew point temperature) if the ambient temperature is low (10 °C), at regeneration temperatures of 60 and 70 °C. The highest rate of water extraction and the highest yield is 10.9 g s−1 and 62.2 kg kWh−1, respectively, under ambient conditions of 26 °C and 0.02 kg kg d.a.−1. Under the winter (when the absolute humidity is at its lowest) weather conditions of Dubai, as much as 39.3 kg of water can be produced per kWh, which translates to only 0.59 cents per kg water produced. [ABSTRACT FROM AUTHOR]

In this study, the performance potential of oil palm fruit mesocarp fiber (OPFMF) as a natural bio-adsorbent for the adsorptive crude oil bio-sequestration from seawater as well as the effect of four bio-adsorption factors (initial crude oil concentration (A), oil-seawater temperature (B), bio-adsorbent dosage (C), and bio-adsorbent particle size (D) together with the factors and performance optimization were determined using the Taguchi orthogonal array of four factors and three levels (L9(34)) design. Bio-sequestration efficiency (%) and bio-adsorption capacity (g/g) were performance evaluation indices. The adsorptive bio-sequestration mechanism was determined by fitting the adsorptive data to known kinetic and isotherm models. The percentage contributions of the factors that significantly impacted the bio-sequestration efficiency are, D (58.77%), A (37.82%), and C (3.29%) factors, as well as C (73.67%) and A (22.62%) factors for the bio-adsorption capacity. An optimum bio-sequestration efficiency of 97.25 ± 0.27% was obtained at an optimum significant factors' combination of A (7.80 g/L), C (3.00 g), and D (1.18 mm), while an optimum bio-adsorption capacity of 12.66 ± 0.06 g/g was achieved at an optimum significant factors' combination of A (15.6 g/L) and C (1.00 g). The adsorptive bio-sequestration followed the Dubinin-Rudeshkevich isotherm (maximum bio-adsorption capacity ( Q m ) found to be 0.3070 mole/g) and pseudo-second-order kinetics, with the liquid film diffusion being the major rate-controlling step and chemisorption being the predominant adsorptive bio-sequestration mechanism. Conclusively, OPFMF can serve as an effective natural bio-adsorbent for oil spill adsorptive bio-sequestration. [ABSTRACT FROM AUTHOR]

Over Northeast China, the area surrounding the Horqin sandy land (HSL) is an important plantation domain within the "Three north" Area of China. Compound heat waves and droughts can exert exceptionally negative impacts on ecosystems. However, less attention has been paid to the physical causes of the variability of the frequency compound droughts and heatwaves in this peculiar sandy region. In this study, salient climatic factors tied to the variability of the number of compound drought and heatwave day (CDHD) around HSL in late summer (July–August) are identified. Results show that the preceding wintertime El Niño–Southern Oscillation (ENSO)-associated SST mode can exert significant delayed impacts on the interannual CDHD fluctuations around HSL in the following late summer, serving as a precursory oceanic factor. Dynamical and thermodynamical diagnoses associated with the observational evidences and the Community Earth System Model version 2 (CESM2) tropical Pacific pacemaker experiment outputs reveal and confirm that the negative phase of ENSO (i.e. La Niña-associated sea surface temperature mode) in the prior winter can exert cross-season impacts on the enhanced CDHDs around HSL in the subsequent late summer through a critical synchronous atmospheric bridge of the western North Pacific cyclonic anomaly. This system may connect an anticyclonic anomaly prevailing over Northeast Asia via an anomalous meridional overturning circulation, which could act as a salient synchronous atmospheric factor. In this circumstance, favorable in situ meteorological and land surface conditions (e.g., increased 2-m maximum air temperature and suppressed rainfall/soil moisture deficiency) can be established, eventually sparking abnormal heat and drought conditions surrounding HSL and thus producing more late-summer CDHDs around HSL. [ABSTRACT FROM AUTHOR]

During the life cycle of a tropical cyclone from the homogeneous ocean-phase to the heterogeneous land-phase, estimating the catchment-scale evapotranspiration (ET) for agricultural water management is a challenging task. For assessing the catchment-scale ET and the causative weather variables associated with the land–atmosphere interactions during the Tropical Cyclone Phailin (TC Phailin), some popular parameterization scheme combinations in the Weather Research and Forecasting (WRF) model were selected. The suitability of different WRF parameterization scheme combinations (PSCs) were evaluated in the Brahmani River basin in eastern India to reproduce the observed weather variables of surface (2-m) air temperature, precipitation and atmospheric pressure at hourly and daily temporal resolutions during the pre-, at-, and post events of the TC Phailin. This study found that the 'Rapid Update Cycle' (RUC) LSM with 'Purdue Lin' microphysics and 'Arakawa convective' cumulus scheme performed the best. Overall, the PSCs could simulate the surface air temperature better than the precipitation during the short timeframe of the extreme event, whereas the overall regional pressure simulation showed a constant bias. The results reveal that WRF-LSM model that accounts for both local (clothesline) and global (oasis) advection effects could better simulate the ET flux compared to the corresponding MOD16A2 remote sensing product and the Food and Agricultural Organization (FAO)-56 Penmen-Monteith (PM) equation, especially during cloudy days. The local feedback of the TC Phailin over the land-surface ET flux and its climatic and land-surface drivers (soil moisture) during the pre-, at-, post-cyclone events reveal that: (a) the negative Bowen Ratio estimates during the heavy rainfall resulted in a reduced ET flux, (b) the negative sensible heat flux during this period facilitates for flow of heat from surface to atmosphere, cooling the soil of the river basin. Overall, this study aids in a better understanding of the moisture flux and energy transfer dynamics between the land–atmosphere system during the onset of a cyclone. [ABSTRACT FROM AUTHOR]

The analysis of air temperature data from May to September for the period 1966–2022 has revealed the occurrence of extreme phenomena, such as tropical nights and hot days, in the Lake Baikal area. The occurrence, multiyear and intra–annual variability of these extreme phenomena was investigated for the first time. The analysis identified two groups of stations, which are differ in the number and distribution of tropical nights and hot days. The first group, which includes inland and coastal stations, has higher values of the frequency of occurrence of tropical nights (0.21–1.68 days yr –1) and hot days (0.74–8.05 days yr –1). The second group, consisting of coastal, highland and island stations, has predominantly tropical nights (0.19–0.26 days yr –1). After 1990, these extreme events became more frequent. Tropical nights occur between June and September, while hot days are common from May to August, with the highest frequency of both in July. In this month, the proportion of tropical nights and hot days is identical and is 57% of their total number. July is the hottest month in the region. The increase in the frequency of tropical nights and hot days in the Baikal region is mainly due to global warming and changes in global circulation. The occurrence and variability of these extreme phenomena also depend on various factors related to the peculiarities of regional climate warming and local circulation of air masses, as well as on environmental conditions surrounding each station. [ABSTRACT FROM AUTHOR]

The escalating frequency and intensity of extreme climate events pose significant challenges in the context of the climate crisis, leading to substantial human and economic losses. This study aims to assess trends and disruptions in extreme climate indicators, focusing on precipitation and air temperature, within the watersheds of eastern Paraná state. Data from 1976 to 2015 were used, ensuring record failure rates below 5%. Trend analysis employed the extreme climate indicators developed by the Canadian Meteorological Service and the Mann-Kendall test, while discontinuities in the historical series were identified using normality tests (Pettitt, SNHT, and Buishand). Results revealed increasing trends in annual precipitation totals (PRCPTOT), the annual total of rainfall exceeding 95% of percentiles (R95p), and, notably, the index of daily rainfall concentration (SDII). The Upper Ribeira watershed displayed the highest frequency of trends associated with SDII. Moreover, widespread upward trends in air temperature were observed, particularly in Curitiba, where the average annual minimum temperature rose by 1.8 °C. Notably, many discontinuities in the historical climatic series were detected between the late 1980s and early 2000s. This research provides a comprehensive understanding of the modifications in extreme climate indicators in the study area, emphasizing significant trends of more heavy and concentrated rainfall and a robust increase in average air temperature. [ABSTRACT FROM AUTHOR]

Drylands, where the water supplies are scarce relative to the atmospheric moisture demands, occupy approximately half of the area of China. With global warming, the response of atmospheric water cycle is a crucial concern for sustainable development in China's drylands. This study investigates the characteristics of the water cycle in China's drylands during 1980–2019, as well as future projections estimated by the Community Earth System Model (CESM) during 2020–2100. The results show that the air temperature in China's drylands has increased significantly since 1980, especially after 2000, with greater warming in the warm season. Meanwhile, China generally tend to be drier from 1980 to 2019 as a whole, especially in the cold season. Both precipitation (P) and evapotranspiration (E) have increased, but the net effect is that drylands become drier (negative P-E) and wetlands become wetter (positive P-E), respectively. In the future, drylands are projected to become more humid due to increased precipitation, showing a pattern of "western wetter and eastern drier" during 2020–2100. These results could improve understanding of the water cycle and provide some guidance for adapting to climate change in drylands. [ABSTRACT FROM AUTHOR]

The air temperature lapse rate (TLR) is one of the essential parameters for glacio-hydrological studies. However, TLR estimations are limited in the glacierised regions of Himalaya due to a scarcity of long-term observations. Therefore, a dense in-situ monitoring network over a high Himalayan region is needed to estimate the TLR accurately. Here, in-situ air temperature data is obtained from Automatic Weather Stations (AWS) installed over the Chandra basin, western Himalaya, from October 2020 to September 2022. This data is used to estimate the TLR by regressing the air temperature with the corresponding elevations. We estimated the mean annual TLR of 3.8 ± 0.3 °C km-1 for the entire Chandra basin, significantly less than the standard environmental lapse rate (6.5 °C km-1). We found substantial seasonal variability in each TLR time series. The maximum TLR is 5.8 ± 0.2 °C km-1 during the summer, and the minimum is -1.6 ± 0.1 °C km-1 during winter, comparing all the meteorological stations. Further, we observe strong diurnal fluctuations of TLR, which has maximum and minimum values during 10:00 to 18:00 hrs and 20:00 to 09:00 hrs, respectively. The study highlights that the temporal variability of TLR is site-specific and strongly correlated with wind speed, relative humidity, and radiation fluxes. Furthermore, a temperature-index model is used to assess the implications of TLR by estimating glacier mass balance. This study highlights the importance of considering observed TLR to accurately model surface mass balance over the glacierised Himalayan region. [ABSTRACT FROM AUTHOR]

Frost on agricultural products in spring imposes heavy financial losses to agriculture particularly in northwest of Iran's orchards. Frost early warning is an effective way in preventing frost risk in apple orchards. This paper aims to validate frost early warning system in apple orchards of northwestern Iran by predicting flowering date of apple tree and its combination with WRF (Weather Research and Forecasting) model simulations of the 2-m temperature. To this end, stepwise multiple linear regression model was used for predicting flowering date; therefore thermal variables data including mean temperature, mean maximum temperature, mean minimum temperature, last frost date, heat wave duration, heat wave intensity, GDD and maximum standard temperature data larger than 1 (Z > 1) for the period of 2007–2016 (from March 1st until flowering date) in Kahriz agrometeorological station in northwest of Iran were calculated and added to the model. Also, to evaluate the accuracy of WRF model simulations, the 72-h simulations of the 2-m air temperature for internal computational grid in northwestern Iran (West Azerbaijan Province) in 17 synoptic stations were compared to minimum air temperature observed in the stations. Results revealed that the proposed stepwise regression method is a relatively precise model with a mean absolute error of 2.7 days between the predicted and observed flowering dates. Findings were also indicative of an acceptable accuracy of 72-h minimum air temperature simulations of WRF model in the study area. [ABSTRACT FROM AUTHOR]

In this study, high-resolution anthropogenic heat release (AHR) due to energy consumption is considered in Community Earth System Model version 1 (CESM1) to explore possible climatic effects and physical mechanisms due to AHR in eastern China (EC) in boreal summer. The results show that the heating effect of AHR on the lower atmosphere leads to an increase in the temperature difference between land and ocean, causing changes in atmospheric circulation and water vapor transport in EC in boreal summer. AHR affects the lower-troposphere stability and low clouds, impacting the surface energy balance. This will affect the surface temperature and further increase the occurrence of extreme high temperatures. The modeling results show that in the central part of the Beijing-Tianjin-Hebei and Inner Mongolia regions, the relative humidity increases by more than 1% due to AHR, leading to a decrease in low cloud cover. In the Middle-Lower Yangtze region, low clouds decrease by 2–3%, while the net shortwave radiation flux at the surface increases by approximately 5%. AHR leads to an increase of 0.19 K in the 2 m air temperature in the 25°N-35°N regions of EC on average in boreal summer, which will further impact the summer extreme high temperature in the Middle-Lower Yangtze Region. AHR acts as a non-negligible factor for the extreme high temperature in EC in boreal summer. [ABSTRACT FROM AUTHOR]

Scientific interest is increasingly drawn towards regional meteorological extremes, given their impacts on populations, infrastructure, and ecosystems. These extremes are shaped by complex interactions between internal climate variability and long-term trends. The aim of the present work is to evaluate changes in high-frequency variability and the influence of long-term trends on the frequency of occurrences of extremes, with a focus on surface temperatures over the period from 1962 to 2022 in Emilia-Romagna, a region of Northern Italy. Daily data of 2 m air temperatures averaged over the region are retrieved from ERACLITO, a high-resolution climate analysis. The distributions of daily temperature anomalies show a general broadening in 1992–2022 with respect to 1962–1991. This is true for maximum, minimum, and mean daily surface temperatures, especially during the summer and spring seasons. A significant warming trend of 0.37 °C/decade is detected in annual mean surface temperatures over the period considered. The study is completed with a comparison between the observed frequency of record-breaking annual temperature events, a hypothetical stationary climate distribution and a theoretical derivation that accounts for changes in trends and variability. During the last decade, the theoretical count of extreme events is 1.26, which yields a likelihood of 86% that this is owed to the trend rather than interannual variability. Idealized experiments demonstrate that the expected occurrences of record-breaking events in future decades depend on the warming rate rather than the warming level. Finally, an analysis performed at seasonal level shows that the majority (minority) of record events are occurring in the summer (spring) seasons. [ABSTRACT FROM AUTHOR]

Selin Co basin, a representative lake basin situated in the central region of the Tibetan Plateau (TP), is characterized by extensive areas of frozen ground and has undergone a remarkable expansion in its lake area. Evapotranspiration, as an important variable within the lake water cycle, as well as its influencing factors are still under debate at this basin. Actual evapotranspiration (ETa) plays a vital role in influencing land-atmosphere interaction processes and the hydrological cycle. By quantifying the amount of water that is actually transpired by vegetation and evaporated from soil surfaces, ETa provides important information about the mechanisms controlling evapotranspiration. In this study, the advection-aridity (AA) model was employed to estimate ETa in Selin Co basin. The estimated ETa and its influencing factors were investigated between 2001-2018, with an emphasis on examining both spatial and temporal trends. The results demonstrated that the multiyear mean ETa in the basin was 430.3 mm (excluding lakes) with an overall significantly decreasing trend (-5.8 mm/yr). In terms of its seasonal variation, ETa exhibited highest value during summer, while experiencing comparatively lower rates in autumn and spring. Furthermore, the spatial distribution of both the annual and seasonal ETa exhibited a similar decreasing trend from the southeast to the northwest of the basin. The sensitivity of several meteorological variables to modifications in ETa was also examined. Results indicated that specific humidity was the predominant variable, followed by net radiation, air temperature, precipitation, atmospheric pressure, and wind speed. In addition, the area covered by permafrost and seasonally frozen ground was approximately about 1.58 × 104 km2 and 4.22 × 104 km2 in the basin, and permafrost degradation in the northern region of the Selin Co basin resulted in increased average soil moisture content and underground ice melting, leading to a subsequent increase in ETa. [ABSTRACT FROM AUTHOR]

The intensity of Tropical Easterly Jet (TEJ) is profoundly associated with the Indian Summer monsoon rainfall (ISMR). Epochal analysis of the TEJ intensity has been carried out by dividing the period of 1976–2021 into two equal epochs, E1 (1976–1998) and E2 (1999–2021), with a breaking point corresponding to the 1998/99 climate shift. Further, the evolution of the relationship between ISMR and the intensity of TEJ across the two epochs has also been studied using Mann–Kendall (MK) trend analysis and Innovative trend analysis (ITA) techniques. Diabatic heating over the Tibetan anticyclonic and TEJ regions is also analyzed to study epochal variability. The relationship dynamics are further explored using multivariate correlation analysis of ISMR with the TEJ intensity, meridional temperature gradients (at 150 hPa and 200 hPa), air temperature anomaly index, and outgoing longwave radiation (OLR). The study indicates the reversal or stabilizing of the significant declining trend in the meridional upper-level tropospheric temperature gradient in E2, specifically at 150 and 200 hPa. OLR shows a declining trend of 0.12 Wm−2 yr−1 in E2 with a 90% confidence level, whereas with an insignificant decreasing trend of 0.06 Wm−2 yr−1in E1. An increment in diabatic heating (Q1) and a regime shift is observed in the Tibetan anticyclonic (TP) region in E2 compared to E1. TEJ intensity increased with a confidence level above 90% at 150 hPa (0.04 ms−1 yr−1) and 200 hPa (0.06 ms−1 yr−1.). Longitudinal oscillation in the position of the TEJ core is also observed; specifically, regime shift in the longitudinal position of the TEJ core is observed in E2 compared to E1. Multivariate correlation analysis of TEJ intensity at 150 and 200 hPa; meridional temperature gradient between TEJ and TP region at 150 and 200 hPa; OLR with ISMR indicate increased correlation of tropospheric temperature gradients at 150 and 200 hPa with OLR and ISMR. A marginal increase of 0.05 in the correlation coefficient between TEJ intensity and ISMR is also reported at 150 hPa. [ABSTRACT FROM AUTHOR]

Observations show that the warming trends of annual and seasonal surface air temperature (SAT) in China have been about 0.15 ~ 0.31 ℃/10a in China since the 1950s. The warming trend is higher in winter and spring than in summer and fall, and higher in the northern region than in the southern region. Additionally, the warming trend is higher in the western part of China than in the eastern part, except for spring. These variations have been well simulated by the recent CMIP6 models. Using a perfect model method, the all-forcing (ALL) + anthropogenic aerosol forcing only (AER) + natural forcing only (NAT) strategy has been applied to the detection and attribution of SAT trends in China since 1951. It is found that GHG (greenhouse gas forcing only) is detected robustly in all seasons and regions except winter in eastern China, contributing to a warming of 0.21 ~ 0.36 ℃/10a. This indicates that the greenhouse gas from human activities is the primary factor causing the warming in mainland China over the past 70 years. The contribution of the AER has only been detectable in the variations in summer of the whole mainland China and western China with neglectable effect since the late twentieth century. The NAT forcing can also be neglected. [ABSTRACT FROM AUTHOR]

Achieving simultaneous control over temperature and humidity through a single direct expansion air conditioner would be advantageous, especially considering its widespread use in residential buildings. Traditional control strategies fail to achieve satisfactory control performance due to the nature of complexity and cross-decoupling of the system. Therefore, this research paper presents the advancement of a feedforward decoupling control scheme designed for a direct expansion air conditioning unit to effectively control both temperature and humidity. To facilitate the controller design, a dynamic model considering both sensible and latent heat transfers was developed and verified. The thermal responses of the coupled system were analyzed and their correlation coefficients also examined. Through identifying the transfer function model of the coupled system, a feedforward decoupling controller with two compensators was designed. The proposed decoupling control scheme was tested using the developed model as the plant to be controlled. Test results showed that, in comparison to the transitional PID based dual single-input and single-output controller, the proposed decoupling control scheme was capable of eliminating the interactions between indoor air temperature and humidity under variable speed operation, and realizing the simultaneous control over indoor air temperature and humidity with a desirable control performance. [ABSTRACT FROM AUTHOR]

The performance merits of a mobile air conditioning (MAC) system with an orifice tube (OT) were experimentally evaluated for R1234yf relative to R134a. The effect of employing a suction/liquid line internal heat exchanger (HEX) was also investigated for R1234yf. To this end, an experimental unit employing the components of an R134a MAC system was set up, equipped with a coaxial internal HEX, and tested at various compressor speeds for both refrigerants. The air temperatures entering the condenser and evaporator were simultaneously maintained at 30, 35, and 40 °C. The R1234yf unit provided on average 22.5% lower and 6.9% higher cooling capacity than the R134a unit for the inactive and active HEX, respectively. Furthermore, the coefficient of performance (COP) for the R1234yf unit without and with HEX was on average 10.9% and 3.5% lower than that for the R134a unit, respectively. The R1234yf unit without and with HEX yielded on average 41.5% and 8.4% lower exergetic efficiency than the R134a unit, respectively. These results revealed that the use of an internal HEX in an R1234yf MAC unit with an OT compensates for the cooling capacity degradation, and the R1234yf unit has almost as high performance as the R134a unit. [ABSTRACT FROM AUTHOR]

This study assessed the capability of the historical simulations of phase 5 and 6 of the Coupled Model Intercomparison Project (CMIP5/6) in reproducing the temporal and spatial characteristics of the Interdecadal Pacific Oscillation (IPO) and its impact on global surface air temperature (SAT), surface equivalent potential temperature (Thetae_sfc) and precipitation. The IPO index time series simulated by CMIP5/6 models deviated from observations and struggled to capture the phase evolution characteristics of the IPO. Nevertheless, CMIP5/6 models successfully captured the horseshoe‐shaped sea surface temperature anomaly in the Pacific. Additionally, the CMIP5/6 models were able to simulate the IPO's 10–30‐year period. Notably, the simulated IPO index exhibited a statistically significant upward trend, which was absent in observations. Additionally, the IPO‐related global land SAT, Thetae_sfc and precipitation simulated by CMIP5/6 models performed differently in boreal winter and boreal summer. Furthermore, the IPO‐related global land SAT performed better in CMIP5/6 models during boreal winter than that in boreal summer. In CMIP6 models, it improved during both boreal winter and summer compared to CMIP5 models. In terms of the IPO‐related global land Thetae_sfc, CMIP5/6 models also performed better during boreal winter than in boreal summer. However, CMIP5 models outperformed CMIP6 models during the boreal summer. In terms of the IPO‐related global land precipitation, CMIP5/6 models performed better during boreal summer compared to boreal winter. Moreover, the IPO‐related global land precipitation in CMIP6 models improved significantly in boreal winter, but almost the same in boreal summer, compared to CMIP5 models. Further studies showed that the enhancements in simulating IPO's spatial pattern did not correspond to improvements in the model's ability to simulate IPO's global teleconnections. [ABSTRACT FROM AUTHOR]

Vehicle‐based mobile observations are taken across the world every day by operational and research meteorological organizations, public transportation agencies, and private car manufacturers. Whether directly weather‐related (e.g., air temperature) or not (e.g., wiper speed), the coverage and frequency of these observations holds the promise of filling in gaps between fixed observing stations and greatly improving situational awareness and weather forecasting, from road surface condition‐specific applications and winter road maintenance to urban and street‐level numerical weather prediction and beyond. However, in order to take advantage of these observations, the weather, water, and climate enterprise must work together with the transportation enterprise across academic, public, and private sectors to provide a mechanism for obtaining these data, so that the benefits of using these unconventional observations may be realized. [ABSTRACT FROM AUTHOR]