Air Temperature Research Articles

Real-time paddy grain drying and monitoring system using long range-internet of things

Grain drying environmental parameters are an important issue throughout the paddy grain production process. A real-time monitoring system requires rapid, online, and accurate measurement results. In the paddy grain drying process, the heated air velocity, temperature, relative humidity, and moisture content have to be carefully monitored and maintained to ensure product quality and safety. This study aimed to propose a real-time paddy grain drying and monitoring system using a long-range internet of things (LoRa-IoT). The real-time monitoring system consisted of sensors, LoRa, and IoT platforms. The LoRa end node and gateway were utilized as a wireless radio communication platform of IoT for long-distance signal transmission. From the experiment, the gateway received data from the end node at a distance of 2 km with a time on air (ToA) of 981 ms. As a result, the proposed monitoring system succeeded in measuring and recording the heated air velocity, temperature, and relative humidity data during the paddy grain drying process from 25% moisture content down to 14%. Regarding moisture content, the accuracy of real-time monitoring information was confirmed with a direct measurement method, resulting in a root mean square error (RMSE) of 6.17%.

Prenatal exposure to heat and humidity and infant birth size in Ghana.

Previous studies - primarily in high income countries - have shown that high prenatal temperatures are associated with adverse birth outcomes. However, these studies are mostly focused on average exposure across the full gestational period or short-term exposure immediately prior to delivery and may miss important sensitive windows of exposure in utero. Further, nearly all use ambient air temperature data, which neglect physiologically important interactions between air temperature and humidity. The Ghana Randomized Air Pollution and Health Study (GRAPHS) recruited pregnant individuals from 2013 to 2015 from communities in the Kintampo North Municipality and Kintampo South District of Ghana. We estimated daily maximum shaded wet bulb globe temperature (WBGTmax) and heat index (HImax) during pregnancy and examined associations with birth weight, birth length, head circumference, and incidence of low birth weight, preterm birth, and small for gestational age. Using linear regression analyses, trimester average models identified that higher WBGTmax in the first trimester was associated with larger head circumference; second trimester was associated with shorter birth length, lower birth weight and higher odds of preterm birth, and third trimester was associated with shorter gestational age and larger head circumference. Time-varying analyses using distributed lag nonlinear models find that, compared to the median, lower WBGTmax and HImax (25th percentile) during the first half of pregnancy was associated with higher birth weight and longer birth length. Compared to the median, lower WBGTmax and HImax (25th percentile) in the second half of pregnancy was associated with smaller head circumference while higher wet bulb globe temperature (75th percentile) was associated with larger head circumference. Overall, our study identified that higher WBGTmax and HImax are associated with pregnancy duration and newborn size. Given the overall trend in our study area of rising temperatures, these data suggest that adaptation strategies are urgently needed to protect child health.

Mangrove flourishing/deterioration under the control of the Indian Summer Monsoon over the past ∼3,195 years in Phang Nga Province, Thailand.

Mangrove wetlands are strategic locations for mitigating climate changes. In order to address the harm of rapid climate change to mangrove ecosystems, it is necessary to scientifically predict the fate of mangrove ecosystems, which can be achieved by reconstructing the development history of mangrove forests. This study analyzes the contribution of mangrove-derived organic matter (CMOM) from sediment core F in Phang Nga Province, Thailand by using the endmember mixing model based on stable organic carbon isotopes (δ13Corg) and C/N (molar) ratio. The variations of CMOM over the past ∼3195calyr BP indicate that mangrove forests underwent three periods of flourishing: ∼3195-2620calyr BP, ∼2030-1130calyr BP, and ∼410-0calyr BP, and two periods of deterioration: ∼2620-2030calyr BP and ∼1130-410calyr BP. Among the potential factors that might affect the development of mangrove forests, relative sea level (RSL), regional hydrodynamics, and human activities do not have notable effects on mangrove flourishment/deteriorating. However, climate factors, particularly air temperature, rainfall, and sea surface salinity are the main factors influencing the flourishing/deterioration of mangrove forests. In the Andaman Sea, these climatic factors are mainly driven by the Indian summer monsoon (ISM).

Potassium Sulfate Supplementation with Elevated Electrical Conductivity Was Unproductive for Hydroponic Strawberry at the Original Yamazaki Nutrient Solution Nitrogen Level

The production of strawberries (Fragaria ×ananassa) in hydroponic systems has been increasing. In hydroponic systems, precise nutrient management is crucial for optimal plant growth and fruit production. Among essential elements, potassium (K) is a key nutrient that affects fruit yield and quality in fruiting crops. The objective of this study was to investigate whether increasing the K concentration in the Yamazaki strawberry nutrient solution could enhance plant growth, fruit yield, and fruit quality in hydroponic strawberries. Bare-root plants of strawberry ‘Monterey’ and ‘San Andreas’ were planted in a deep water culture hydroponic system and grown with initial K concentrations of 117, 194, 271, and 348 mg·L−1 under the same initial nitrogen concentration of 77 mg·L−1. As the K concentration increased from 117 to 348 mg·L−1, the nutrient solution electrical conductivity increased from 1.0 to 1.9 dS·m−1. The experiment was conducted inside an indoor vertical farm at a 23 °C air temperature with an extended photon flux density (400–750 nm) of 350 µmol·m−2·s−1 under an 18-hour photoperiod. Increasing the K concentration from 117 to 348 mg·L−1 had minimal effects on plant growth characteristics of both cultivars, although root dry mass of ‘Monterey’ increased linearly with increasing K. Increasing the K concentration from 117 to 348 mg·L−1 did not affect the total fruit number or total fruit fresh mass of ‘Monterey’, but for ‘San Andreas’, it reduced the total fruit number by 34% and total fruit fresh mass by 45%. Additionally, increasing the K concentration from 117 to 348 mg·L−1 reduced the individual fruit mass, fruit length, and fruit diameter and increased titratable acidity in both cultivars. These results indicate that increasing the K concentration in the Yamazaki strawberry nutrient solution did not benefit plant growth, fruit yield, or fruit quality of the hydroponically grown strawberries ‘Monterey’ or ‘San Andreas’.

Thermal discomfort and adaptation strategies in Brazilian social housing

Living with the harmful effects of climate change is a challenge, especially in relation to the marked thermal discomfort resulting from heat waves that mainly impact economically vulnerable populations. The main objective of this study was to analyze thermal comfort in social housing and the strategies adopted by residents to overcome situations of thermal discomfort in hot and humid climates. The object study is composed of four low-income architectural types, located in the city of João Pessoa, northeast Brazil. The field research included on-site evaluations, measuring the thermal conditions inside 156 housing units and conducting semi-structured interviews. The results showed that the housing units analyzed often present internal conditions of thermal discomfort; this condition is a little more critical in homes that added extensions to their dwellings, as a result of interventions carried out by residents after the unit was occupied. One of the consequences of expanding the housing area is the reduction in the percentage of openness of the unit (openness of the enclosure/building envelope), with a major impact on thermal comfort, as approximately 50.0% of the sample presented this particularity. The worst thermal scenario was recorded in the group of single-story houses. These units, in addition to the high degree of thermal discomfort, face health problems resulting from high humidity and air temperature. The main adaptive strategies observed were using a fan and opening doors and windows. The daily average of fan use is 8.0h, resulting in an increase in energy demand.

Comprehensive industry-relevant black soldier fly bioconversion characterisation by a novel chamber system.

Black soldier fly larvae (BSFL) efficiently convert biowaste into valuable animal feed. Sustainable and reliable bioconversion is desirable to achieve optimal economic and environmental outcomes. Thus, science and industry require an accessible research platform to study complex bioconversion processes under conditions mirroring industrial-scale settings. In this study, industry-relevant respiration chambers were designed, tested, and replicated for BSF feeding trials. Each open-circuit chamber housed three industrial rearing crates. The substrate/frass and air temperature, mass change, NH3 and CO2 emissions, and relative humidity were measured. The design was validated for CO2 recovery, airtightness, airflow homogeneity, and BSFL performance using firstly, a uniform control substrate and secondly, uniform food waste across four parallel chambers. In a third trial, the composition of food waste was varied across parallel chambers to detect differences in metabolic processes. For trials using uniform substrates, low variability across chambers in performance parameters confirmed the reproducibility and comparability of the design (e.g. bioconversion rate: <1%, final larval mass: ≤2 mg, standard deviations, dry matter based). In contrast, the trial with varying food waste compositions showed a strong effect on average substrate/frass temperature (e.g. 31.5 °C vs 41.8 °C) and final dry larval mass (e.g. 67 mg vs 40 mg). This is the first study to systematically assess heat generation directly from heterogeneous food waste, a crucial parameter for efficient BSFL bioconversion. These chambers provide an opportunity for science and industry to thoroughly assess and understand the metabolic bioconversion characteristics. The findings are key for the optimisation of sustainable bioconversion processes.

Exploring building performance evaluation methods to estimate energy savings following field implementation

Research on energy conservation measures and advanced control strategies is becoming increasingly present to improve building energy performance and may reach the stage of field testing in existing buildings. Therefore, it becomes critical to properly assess the benefits following on-site implementation. Different approaches have been conducted in the past to predict building energy performance and evaluate energy savings. However, it remains not clear how the calculation methods and their underlying assumptions eventually influence the savings estimates. This paper aims to compare the energy savings obtained following the implementation of data-driven measures in an existing building and estimated using three different approaches that are commonly found in the literature. The intricacies of these baseline model-free and baseline model-based methods were investigated, and various aspects were explored such as weather normalization, baseline modelling time-step (monthly, daily, hourly, sub-hourly), input sets (including weather, time-index variables, room air temperatures, heating system conditions), and techniques (linear, multi-linear, gaussian process regression). Results show that savings estimates can significantly vary from one performance evaluation method to another, and from one model to another, highlighting the importance of properly selecting both the evaluation method and the baseline model. Baseline model-based approaches were found more appropriate than the other methods, and daily linear regressions against outdoor air temperature and hourly gaussian process regression using weather and time-index variables were found suitable for building performance evaluation.

Effects of Reduced Substrate Volumetric Water Contents on the Morphology and Physiology of Three Landscape Shrubs Grown in a Greenhouse

Reduced precipitation and increasing temperatures caused by climate change have escalated the irrigation requirements for maintaining the aesthetic quality of urban landscape plants. Many cities in the western United States now mandate the incorporation of drought-tolerant plants in new landscapes because of concerns regarding water scarcity. However, a knowledge gap persists regarding the drought tolerance of ornamental plant species commonly used in urban landscapes. The objectives of this study were to determine the effects of decreased volumetric water contents on the morphology, physiology, and plant growth of Rosa ×hybrida ‘Meibenbino’ (Petite Knock Out® rose), Salvia rosmarinus ‘Arp’ (‘Arp’ rosemary), and Vitex agnus-castus ‘SMVACBD’ (Blue Diddley® chaste tree). Twenty-four plants of each species were randomly assigned to an automated irrigation system, and the substrate volumetric water content was maintained at 0.40 or 0.20 m3⋅m−3 for 50 days. As the substrate volumetric water content declined, plants exhibited an increase in the proportion of visibly wilted and damaged leaves as well as chlorosis. Rose, rosemary, and vitex experienced up to a 30% decrease in the plant growth index [(height + width 1 + width 2)/3], whereas leaf dry weights (DWs) decreased by 84%, 66%, and 58%, respectively. Landscape plants in this study acclimated to drought stress by reducing the total leaf area, developing small leaves, increasing the root-to-shoot ratio, and decreasing stomatal conductance. However, stomatal closure also led to increases in leaf temperatures because of limited transpirational cooling efficiency. For the rosemary, trichome density on the adaxial surface increased as the substrate volumetric water content decreased. The trichome density might be regulated by turgor-pressure-driven cell expansion because the trichome density decreased with the increased leaf width. Rose was sensitive to decreased substrate water availability, resulting in severe growth reduction with a high leaf–air temperature difference. Rosemary maintained better visual quality than that of rose, but the low root-to-shoot ratio resulted in a high leaf-air temperature difference. Vitex, which had the highest root-to-shoot ratio, exhibited the lowest canopy–air temperature and lower growth reduction. Overall, under the experimental conditions, S. rosmarinus ‘Arp’ and V. agnus-castus ‘SMVACBD’ showed better tolerance to drought stress compared with that of R. ×hybrida ‘SMVACBD’.

Green roof performance monitoring: Insights on physical properties of 4 extensive green roof types after 2 years of microclimatic measurements

Green infrastructure elements like green roofs provide a range of ecosystem services to urban areas. Although shallow extensive green roofs contribute less to stormwater retention and microclimatic improvement than other green roof types, they remain the most widely used system in European market. This study aims to establish a basis for optimizing green roof designs by thoroughly examining the differences in the physical characteristics of the roofs as well as their environmental impacts and performances in relation to their properties. Two years of microclimatic monitoring on four green roofs revealed distinctly different behaviors regarding evapotranspiration, substrate moisture, substrate temperature, ground-level air temperature, and heat flux. The performances in evapotranspiration and cooling of ground-level air temperature in summer were clearly related to substrate thickness and water storage capacity of the roofs. Furthermore, differences in rainwater interception and stomatal conductance were quantified among various plant species. The results highlight that green roofs with thick substrates or large water storage capacities, combined with highly transpiring and densely growing plant species are most likely to deliver the ecosystem services needed in cities. The collected data also proofs to be essential for high-precision modeling of green roofs’ microclimatic effects in the context of urban planning.

Characterizing Model Uncertainties in Simulated Coast-to-Offshore Wind over the Northeast U.S. Using Multi-platform Measurements from the TCAP Field Campaign

Numerical weather prediction models, such as the Weather Research and Forecasting model, are widely used to provide estimates of the offshore wind energy resource owing to their large spatial coverage compared to available observations. Nevertheless, spatiotemporal distribution of model biases is highly dependent on factors including model configuration, location, and the interplay of multiscale physical processes. Here we focus on the characterization of model uncertainties in simulated coast-to-offshore winds over the northeast United States by varying sea surface temperature (SST) forcings and surface layer (SL) and planetary boundary layer (PBL) parameterizations, as well as identifying biases that may be directly passed from initial and boundary conditions. Multiple measurements, including aircraft data collected during the U.S. Department of Energy's Two-Column Aerosol Project experiment, are used to constrain the model results, and facilitate quantitative comparisons. Our analysis indicates that while SST forcing has notable impacts on simulated air temperature and moisture within PBL, the modeled winds are in general more sensitive to the choices of SL and PBL physics than to SST. The model’s forcing data not only controls the vertical dependence of wind speed errors, but also alters regional variability in the wind speed’s spatial correlation, which underscores the impact of initial and boundary conditions on simulated winds. Coastal and offshore near-surface wind speed biases tend to exhibit much higher similarity in winter than in summer due to the presence of much stronger and more persistent synoptic wind conditions. This study highlights the importance of accurate atmospheric forcing and parameterization choices in improving wind forecasts and suggests the potential for extrapolating coastal wind biases to offshore locations, aiding wind energy forecasting and informing the third Wind Forecast Improvement Project.

Near-surface air temperature estimation for areas with sparse observations based on transfer learning

Near-surface air temperature estimation for areas with sparse observations based on transfer learning

Numerical investigation on the synergistic effect of intake air temperature and hydrogen volume ratio on combustion and emissions of ammonia-enriched hydrogen spark-ignition engine

Numerical investigation on the synergistic effect of intake air temperature and hydrogen volume ratio on combustion and emissions of ammonia-enriched hydrogen spark-ignition engine

Exploring air temperature variability and socio-demographic inequalities in heat exposure through machine learning: A case study of Maricopa County, Arizona

Exploring air temperature variability and socio-demographic inequalities in heat exposure through machine learning: A case study of Maricopa County, Arizona

Thermal data from Málaga's historical centre: Surface and air temperature measurements captured via mobile station and thermal imaging

Thermal data from Málaga's historical centre: Surface and air temperature measurements captured via mobile station and thermal imaging

Role of Infiltration on Land–Atmosphere Feedbacks in Central Europe: Fully Coupled WRF-Hydro Simulations Evaluated with Cosmic-Ray Neutron Soil Moisture Measurements

Abstract The skill of regional climate models partly relies on their ability to represent land–atmosphere feedbacks in a realistic manner, through coupling with a land surface model. However, these models often suffer from insufficient or erroneous information on soil hydraulic parameters. In this study, the fully coupled land–atmosphere model WRF-Hydro driven with ERA5 reanalysis is employed to reproduce the regional climate over central Europe with a horizontal resolution of 4 km for the period 2017–20. Simulated soil moisture is compared with data from cosmic-ray neutron sensors (CRNSs) at three terrestrial environmental observatories. Soil hydraulic parameters from continental and global digital soil datasets (SoilGrids and EU-SoilHydroGrids), together with Campbell and van Genuchten–Mualem retention curve equations, are used to assess the role of infiltration on modeled land–atmosphere feedbacks. The percolation parameter is calibrated to better capture observed discharge amounts in the observatories. WRF-Hydro with Campbell and SoilGrids gives the lowest mean annual temperature and mean annual precipitation differences compared to the E-OBS product from European Climate Assessment and Dataset, which is achieved by reducing soil moisture in the rootzone, increasing air temperature, and decreasing precipitation through a positive soil moisture–precipitation feedback process. WRF-Hydro with van Genuchten–Mualem and EU-SoilHydroGrids best reproduces CRNS soil moisture daily variations, despite enhanced positive biases that generate a larger proportion of convective precipitation favored over wet soils and spurious discharge peaks. This study demonstrates the importance of infiltration processes to realistically reproduce land–atmosphere feedbacks. Significance Statement The ability to correctly reproduce the feedbacks between land and atmosphere is crucial for a regional climate model. This study shows that the nature of these land–atmosphere feedbacks is partly related to the description of soil infiltration, which potentially helps to improve regional climate modeling results. An updated method to disentangle the proportion of convective precipitation being favored over wet, dry, and mixed soils is provided, which sheds new light on the soil moisture–precipitation feedback mechanism.

Activity hours: Assessing liveability during heatwaves

As climate change increases the frequency and severity of heatwaves, understanding their impact on the well-being, health, and permissible activities of building occupants becomes crucial. Existing work focuses primarily on the thermal comfort of an average individual, neglecting both the impact of extreme heat on liveability and variability in resilience of different population groups. To address these gaps, we introduce the Activity hours (Ah) metric, which quantifies the liveability of indoor environments during heatwaves while taking into account air temperature, humidity, occupant age, permissible activity levels, and duration of exposure. We also present the Heatalyzer tool that allows the computation of Ah for different geographies, building archetypes, and heatwave durations. Through a case study of residential housing in London, we compare Ah with established thermal comfort metrics, highlighting Ah’s ability to quantify heatwave impacts on occupant liveability for different building types and demographic groups. Our results are made widely accessible through the Heatalyzer dashboard, an intuitive website that enables London residents to evaluate their exposure to heat-related risks.

Degradation of Toluene via DBD: Detailed Kinetic Reaction Mechanism

The degradation of toluene via Dielectric Barrier Discharge(DBD) has been extensively studied experimentally, however, the reaction mechanism remains elusive, with a dearth of theoretical research. This paper focuses the reaction mechanism of toluene degradation by DBD, developing a detailed kinetic model that encompasses 122 species and 688 reactions. Through the inference of intermediate products from experimental, 661 reactions involving heavy species were established. Finding a lowest-energy reaction path for toluene open loops in conjunction with transition state(TS) theory. Detailed kinetic modelling was carried out to explore the factors affecting toluene degradation. The main species degrading toluene was found to be ·OH, followed by ·O. The degradation rate of toluene was substantially increased by humid carrier gas. The main degradation pathway of toluene is dehydrogenation from methyl groups, conversion to six-membered rings, five-membered rings, and finally ring-opening degradation. Simulation to explore species distribution in a reactor. Electron and excited state densities are predominantly in the intermediate region, and contaminant and carrier gas densities are predominantly in the vicinity of the electrodes. Increasing the inlet air temperature makes the plasma discharge more uniform and the toluene degradation more complete.

Experimental Research of Heating Characteristics on An Air Source Heat Pump System with Capillary Direct Floor Radiant

A new-type air source heat pump system with capillary direct floor radiant (ASHPCFR) was proposed, in which the vapor refrigerant condensed directly in the capillary under the floor to heat the room. Theoretical calculation of heat transfer in the capillary floor was conducted. The results indicated that the optimal capillary spacing should be 100 mm and it was best for a thickness smaller than 60 mm with the floor cement layer. An experimental apparatus for the ASHPCFR system was developed, and its low-temperature heating process and normal heating process were experimentally investigated. Experimental results showed that when the outdoor temperature was -5 °C, the indoor air temperature reached 20 °C after 120 minutes of running, while the temperature difference of a 20 mm thick cement floor could reach 1.73 °C and its maximum temperature could reach 27.5 °C. When the outdoor temperature was -10 °C, the system heating COP was stable at 3.06.

Simulated isotopic fingerprint of the Atlantic Multidecadal Oscillation over South America and its relation to the Little Ice Age

Linkages have been established between the Atlantic Multidecadal Oscillation (AMO) and surface air temperature variations, low-level jet streams, and precipitation trends in both northeastern Brazil and southeastern South America. Previous studies have discerned distinct wet-season (March–May) precipitation responses in northeastern Brazil, with cold (warm) AMO phases triggering increased (decreased) precipitation. Findings from various records indicate that the AMO's variability extends for thousands of years. A recent reconstruction suggests a significant AMO role in the shift from the Medieval Climate Anomaly (MCA) to the Little Ice Age (LIA) and reveals the LIA as the longest period with a persistent cold anomaly in the North Atlantic over the past ∼3 millennia. Stable oxygen isotope records from South America show typical AMO periodicities (~65 years), however, despite increased paleo precipitation data, the AMO's role in South American precipitation during the LIA and MCA remains unclear. In this study, the influence of AMO phases on atmospheric dynamics, precipitation patterns, and stable oxygen isotope composition (δ18O) of precipitation over South America is assessed using the water isotope-enabled version of the Community Earth System Model version 1.2 (iCESM1.2). This research sheds light on the connection between AMO-induced precipitation anomalies and isotopic signals observed in paleoclimate records and emphasizes the significance of isotope-enabled climate models in unraveling the mechanisms behind past variations. The analysis involves comparing δ18O simulations with published reconstructions from South America. By utilizing climate models that incorporate isotopes, we can delve deeper into understanding the impact of the AMO on precipitation patterns and isotopic ratios. Contrary to expectations, the simulated δ18Op signal differ from speleothem records over the western Amazon and Andes during the LIA. That is, the simulated significant total precipitation amounts change over the western Amazon and Andes are not reflected in δ18Op depletion.

Architectural coatings and temperature Adaptive radiative cooling strategies applied in ten climate zones in China: Annual energy consumption Reductions and potentials

This research evaluates the energy-saving potential of high-reflectivity building materials, including three common coating types—normal (absorptivity 0.8, emissivity 0.8), cooling (absorptivity 0.2, emissivity 0.9), supercooling (absorptivity 0.05, emissivity 0.95), and Temperature-Adaptive Radiative Cooling (TARC) materials across 49 representative cities within ten climate zones in China using computational fluid dynamics simulations combined with the Demand.ninja energy consumption model. The results reveal that optimal solar absorptivity varies significantly between different climate zones, with higher absorptivity benefiting colder regions and lower absorptivity benefiting hotter regions. Urban microclimate simulations confirm that low solar absorption materials effectively reduce wall temperatures during the daytime and boost overall cooling energy savings, despite a slight increase in ambient air temperature. Building height-to-width ratios also influenced energy efficiency, with the best performance observed at a ratio of unity for both cooling and supercooling materials. Additionally, tests on the Temperature-Adaptive Radiative Cooling (TARC) materials demonstrate that TARCs offer significant energy-saving advantages, achieving an annual saving of 23.1 billion kWh across China by effectively balancing heating and cooling demands across different seasons. This superior performance is primarily attributed to TARCs’ ability to mitigate increased heating energy demands often associated with conventional cooling materials, especially in regions with substantial winter heating needs. Present research has highlighted the importance of climate-specific building material strategies and the potential of innovative materials like TARC for reducing energy consumptions, and this could favour the low carbon urban development.