Annual Totals Research Articles

Spatial analysis of daily rainfall concentration in Paraíba State, Brazil

Recent studies indicate a reduction of total rainfall and an increase of extreme rainfall events in the Brazilian Northeast region. It is crucial to understand the concentration of daily rainfall for environmental planning and land management. This study performs the analysis of the daily rainfall concentration for the Paraíba State in the period between 1970 and 2019, using data from 26 rainfall stations across the State. Additionally, to the total annual precipitation (PP), the following concentration indicators were applied: frequency of days with precipitation up to 20mm (R20MM), maximum daily rainfall (Rx1Day), maximum rainfall over 5 days (Rx5Day), frequency of days with precipitation in the 10th (P10), 90th (P90), 95th (P95), and 99th (P99) percentiles, number of rainy days (NRD), and the Concentration Index (CI), which estimates the contribution of daily rainfall to the annual total. The Mann-Kendall test and Sen's slope were applied to identify possible trends in the time series and its magnitude. Spatially, the highest concentration values were observed in the Litoral and Brejo regions, decreasing towards the State hinterland. Temporally, most indicators displayed negative trends, suggesting reductions in both annual rainfall totals and rainfall on isolated days or groups of days. However, the CI showed predominantly an upward trend, indicating increased rainfall concentration. P10 values also exhibited an increase tendency, suggesting that days with the lowest rainfall amounts are becoming more frequent.

The role of immune regulation and immunomodulation of the endometrium in the prevention of recurrent implantation disorders and miscarriages

Infertility affects 8 to 12% of couples in the world who are of reproductive age; of these, half seek medical help, and the other 22% undergo fertility treat­ments. An annual total of ART cycles are con­duc­ted because to the rising prevalence of infertility; 15% of patients have repeated implantation failures. As reported by ESHRE in 2018, the live birth rate (LBR) at the third attempt was 20.3% and 17.2% at the fourth attempt [1,2]. Human implantation is a three-stage process, in­clu­ding apposition, adhesion, and invasion. During the apposition phase, the blastocyst contacts the endometrium, mediated by adhesion molecules. The endometrium undergoes changes to prepare for im­plan­tation, providing nutrients and support. The ap­po­sition and adhesion phase is crucial for successful implantation. Invasion occurs during the adhesion phase of implantation, where the blastocyst interacts with the endometrial surface, triggering inflammatory-like res­ponses. This interaction triggers a cascade of events, including cytokines and chemokines, leading to the attachment of the blastocyst to the endo­met­rium. This inflammatory response prepares for human invasion, involving the formation of endo­vascular extravillous trophoblasts (EVTs).

Urbanization and hydrological dynamics: a 22-year assessment of impervious surface changes and runoff in an urban watershed

The frequency and intensity of flooding have been increasing in urban watersheds. Urbanization disrupts natural landscapes by replacing vegetated areas with impervious surfaces, reducing infiltration and increasing runoff. The objective of this study was to evaluate the relationship between change in impervious surface area and runoff amount of Mihang’o watershed located in the outskirts of Nairobi for the period 2000–2022. The specific objectives of this study were as follows: To determine the change in the impervious surface area of Mihang’o watershed, the trend of precipitation amount in the watershed, and the trend in runoff amount, a major source of flood water from the watershed. Supervised classification was performed on land satellite (Landsat) images to determine percentages of impervious surface cover for the study period, and linear regression analysis was used to establish the trend. Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) rainfall data were retrieved from Google Earth Engine, then processed to produce monthly and annual rainfall totals, and Mann–Kendall trend tests were used to establish the rainfall trend for the watershed. The Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) model was used to simulate runoff from the watershed with the rainfall data and impervious surface area percentages as inputs; then, linear regression analysis was performed to establish the runoff trend. The impervious surface area increased by 87.03% from 2.88% (0.49 km2) of the total surface area of the watershed in 2000 to 22.21% (3.91 km2) in 2022, demonstrating an approximate increment of 3.96% (0.88 km2) each year. The Mann–Kendall trend test results (Sen’s slope results [β = 0.832], Kendall’s tau results [τb = 0.146], and p-value [0.625]) confirmed that there is no significant change in rainfall amounts. Runoff increased by 84.75% from 0.18 mm in 2000 to 1.18 mm in 2022; otherwise, an approximate increment of 3.85% (0.045 mm) was evident each year. Besides the impervious surface area, the HEC-HMS model factors in the length of slope, length of reach, soil type, size of subbasins, and longest flow path, thus producing accurate runoff estimations.

Drivers and Annual Totals of Methane Emissions From Dutch Peatlands.

Rewetting peatlands is required to limit carbon dioxide (CO2) emissions, however, raising the groundwater level (GWL) will strongly increase the chance of methane (CH4) emissions which has a higher radiative forcing than CO2. Data sets of CH4 from different rewetting strategies and natural systems are scarce, and quantification and an understanding of the main drivers of CH4 emissions are needed to make effective peatland rewetting decisions. We present a large data set of CH4 fluxes (FCH4) measured across 16 sites with eddy covariance on Dutch peatlands. Sites were classified into six land uses, which also determined their vegetation and GWL range. We investigated the principal drivers of emissions and gapfilled the data using machine learning (ML) to derive annual totals. In addition, Shapley values were used to understand the importance of drivers to ML model predictions. The data showed the typical controls of FCH4 where temperature and the GWL were the dominant factors, however, some relationships were dependent on land use and the vegetation present. There was a clear average increase in FCH4 with increasing GWLs, with the highest emissions occurring at GWLs near the surface. Soil temperature was the single most important predictor for ML gapfilling but the Shapley values revealed the multi-driver dependency of FCH4. Mean annual FCH4 totals across all land uses ranged from 90 ± 11 to 632 ± 65 kg CH4 ha-1 year-1 and were on average highest for semi-natural land uses, followed by paludiculture, lake, wet grassland and pasture with water infiltration system. The mean annual flux was strongly correlated with the mean annual GWL (R2 = 0.80). The greenhouse gas balance of our sites still needs to be estimated to determine the net climate impact, however, our results indicate that considerable rates of CO2 uptake and long-term storage are required to fully offset the emissions of CH4 from land uses with high GWLs.

Prediction of Summer Precipitation via Machine Learning with Key Climate Variables：A Case Study in Xinjiang, China

Study region: Xinjiang is located in the mid-latitude region of Eurasia in northwestern China. Precipitation is predominantly concentrated in northern Xinjiang, while southern Xinjiang remains comparatively arid. Summer precipitation accounts for 54.4% of the annual total. Study focus: This study aims to develop a machine learning model to predict summer precipitation (June–August) in XJ and explore the key variables contributing to summer precipitation in this region. The SHapley Additive exPlanations method was integrated with an extreme tree model to quantify the contributions of variables towards precipitation. Artificial neural networks, support vector machines, and extreme gradient boosting were considered to predict summer precipitation. To train the ML model, we used precipitation data from 1961 to 2012, whilst the forecast results from 2013 to 2017 were used for validation.New hydrological insights for the regions: The results demonstrated that the ANN model achieved robust performance during both the training and validation periods. For Northern and Southern XJ, the Mean Absolute Error and Root Mean Square Error of the ANN model were 15.34 (20.40) and 23.21 (30.01), respectively. The SHAP analysis showed that in the context of Northern Xinjiang, the Niño B Sea Surface Temperature Anomaly, Western Pacific Subtropical High Intensity, Pacific Subtropical High Intensity, and Multivariate ENSO Index play crucial roles in the prediction of summer precipitation. In Southern Xinjiang, the South China Sea Subtropical High Intensity, South China Sea Subtropical High Area, Western Pacific Warm Pool Strength, and Atlantic multidecadal oscillation have emerged as key variables affecting summer precipitation forecasting.

City bus electrification in South Korea: Public preference identified through contingent valuation experiment

To respond actively to issues of climate change and particulate matters, the South Korean authorities have established a plan to electrify all city buses by 2030. This article explores public preferences for city bus electrification in South Korea through the application of contingent valuation (CV). A CV questionnaire was presented to 1000 randomly chosen households along with visual aids to induce their willingness to pay (WTP) for city bus electrification. The payment vehicle and the survey method were selected as bimonthly household income tax and person-to-person interviewing, respectively. As a method of eliciting the WTP, the one-and-one-half-bound dichotomous choice technique was utilized. To analyze the WTP data with numerous zeros, the spike model was employed. The results revealed statistically significant findings. The mean household WTP was obtained as KRW 5195 (USD 4.0) every two months. Expanding this figure to encompass the entire national population results in an annual national total of KRW 680.6 billion (USD 524.7 million). The cost involved in the electrification amounts to KRW 625.0 billion (USD 481.9 million) every year. Therefore, the national WTP outweighs the cost. City bus electrification can be socially justifiable. Furthermore, some policy issues regarding the success of city bus electrification are discussed.

Ecological ICMS (ICMS-E) and Expenditure on Environmental Management and Sanitation Functions in the Context of The Cerrado Biome: an Exploratory Analysis with Municipalities of the State of Mato Grosso do Sul

Objective: The objective of this work was to verify the correlation of the amount of transfers of ICMS-e with the expenses in the environmental management and sanitation functions of the municipalities with a Cerrado area greater than 50%. Theoretical Framework: The creation of the ecological ICMS as financial compensation for municipalities that have a majority of their territory occupied by environmental conservation areas. Method: The sample used is composed of 47 municipalities in the state of Mato Grosso do Sul. The transfer data of the ICMS-e were obtained through contact via institutional email with those responsible for the Management of Conservation Units (GUC) of the Environment Institute of Mato Grosso do Sul (IMASUL). Municipal expenditure data for the environmental management and sanitation functions were obtained from the website of the National Treasury Secretariat (STN) through the Finances of Brazil (FINBRA) application. The time frame of the data was from 2002 to 2012. Pearson's correlation analysis was applied at a significance level of 5% (p <0.05). Results and Discussion: The results show that the relationship between the variables: annual total of transfers of ICMS-e (TAR_ICMS-e) and the annual total of expenditures in the environmental management function (TA_GestAmb) is positive and statistically significant (r = 0.872 and p = 0.000). Research Implications: Given the above, it appears that the strength of the correlation coefficient is strong. Pearson's r coefficient also provides the degree of joint variation of these variables and, therefore, it is estimated that 76% of the investment in TA_GestAmb is a reflection of the transfer received from TAR_ICMS-e. Originality/Value: Regarding the variable: total annual expenditure on the sanitation function (TA_San), the result shows a positive and not statistically significant correlation (r = 0.093 and p = 0.785), however, the effect is practically null.

The Performance of GPM IMERG Product Validated on Hourly Observations over Land Areas of Northern Hemisphere from Global Meteorological Stations

The integrated multi-satellite retrievals for the global precipitation measurement (IMERG) data, which is the latest generation of multi-satellite fusion inversion precipitation product provided by the Global Precipitation Measurement (GPM) mission, has been widely applied in hydrological research and applications. However, the quality of IMERG data needs to be validated, as this technology is essentially an indirect way to obtain precipitation information. This study evaluated the performance of IMERG final run (version 6.0) products from 2001 to 2020, using three sets of gauge-derived precipitation data obtained from the Integrated Surface Database, China Meteorological Administration, and U.S. Climate Reference Network. The results showed a basic consistency in the spatial pattern of annual precipitation total between IMERG data and gauge observations. The highest and lowest correlations between IMERG data and gauge observations were obtained in North Asia (0.373, p < 0.05) and Europe (0.308, p < 0.05), respectively. IMERG data could capture the bimodal structure of diurnal precipitation in South Asia but overestimates a small variation in North Asia. The disparity was attributed to the frequency overestimation but intensity underestimation in satellite inversion, since small raindrops may evaporate before arriving at the ground but can be identified by remote sensors. IMERG data also showed similar patterns of interannual precipitation variability to gauge observation, while overestimating the proportion of annual precipitation hours by 2.5% in North America, and 2.0% in North Asia. These findings deepen our understanding of the capabilities of the IMERG product to estimate precipitation at the hourly scale, and can be further applied to improve satellite precipitation retrieval.

Spatial and Temporal Patterns of Rainfall Erosivity in Southern Africa in Extreme Wet and Dry Years

Soil erosivity is a key indicator of the effectiveness of precipitation acting on the land’s surface and is mainly controlled by event-scale and seasonal weather and climatic factors but is also influenced by the nature of the land’s surface, including relief and vegetation cover. The aim of this study is to examine spatial and temporal variations in soil erosivity across southern Africa using rainfall data for the period 2000–2023 and a gridded raster spatial modelling approach. The two wettest and driest years in the record (±>1.5 standard deviation of rainfall values) were identified, which were 2000 and 2006, and 2003 and 2019, respectively. Monthly rainfall values in these extreme wet/dry years were then analyzed for four rainfall regions (arid, semiarid, subhumid, humid), identified according to their annual rainfall totals. These data were then used to calculate Precipitation Concentration Index (PCI) values as an expression of rainfall seasonality, and the modified Fournier index (MFI) was used to quantify rainfall erosivity. The results show that there are significant differences in erosivity between the different climate regions based on rainfall seasonality and also their distinctive environmental settings. In turn, these reflect the synoptic climatic conditions in these regions, their different precipitation sources, and rainfall totals. The results of this study show that calculated MFI values at the national scale, which is the approach taken in most previous studies, cannot effectively describe or account for erosivity values that characterize different climatic regions at the sub-national scale. Furthermore, the mismatch between PCI and MFI spatial patterns across the region highlights that, under semiarid, and highly seasonal rainfall regimes, episodic rainfall events interspersed with periods of dryness result in significant variability in erosivity values that are unaccounted for by rainfall totals or seasonality alone. In these environments, flash floods and wind erosion result in regional-scale soil erosion and land degradation, but these processes and outcomes are not clear when considering MFI values alone. Fully evaluating spatial and temporal patterns of erosivity in their climatic and environmental contexts, as developed in this study, has implications for sediment and carbon exports, as well as identifying the major regions in which land degradation is an environmental and agricultural issue.

Two Centuries of Monthly Rainfall in Barcelona (NE Spain): Disparity Trends, Correlation of Autumnal Rainfall with the WeMO Index and Its Contribution to Annual Amounts

Rainfall irregularity in Mediterranean regions is a characterizing feature of their climate. The aim of this manuscript is to analyze, in a climate change context, the evolution of this irregularity in Barcelona. A very long monthly database (1786–2023) enables detailed analysis of rainfall evolution, with its irregularity quantified using the concept of disparity, the trends of which are assessed using moving windows and a modified Mann–Kendall test. The relationship between disparity and the Western Mediterranean Oscillation index (WeMOi) is also explored. Additionally, the study compares rainfall amounts to the 1961–1990 reference period and evaluates autumn’s contribution to annual totals. A significant and increasing disparity trend over the years is detected for the autumn months. While correlations between disparity and WeMOi are limited, the WeMOi and monthly precipitation are significantly correlated for two autumn months, October and November, and for December, aligning with previous studies. This suggests the potential influence of the WeMOi fluctuations on future rainfall during these three months. Recent evidence of the increasing autumn irregularity is seen in the consecutive low-rainfall years of 2021, 2022 and 2023, which stand out as the driest since 1835, with the last two autumns ranking among the 5% driest.

How Does Regional Convection‐Permitting Modeling Improve the Simulation of the Atmospheric Water Cycle in Spring Over the Tibetan Plateau?

AbstractThe Tibetan Plateau (TP) provides vital water resources for downstream regions, with spring precipitation contributing considerably to the annual totals over the southeastern TP. The added value of convection‐permitting modeling in simulating the spring climate over the TP is uncertain. Here, we conducted and compared decade‐long regional convection‐permitting (3.3 km) and convection‐parameterized (13.2 km) Icosahedral Nonhydrostatic Weather and Climate Model (ICON) simulations to reproduce the atmospheric water cycle in spring over the TP. Results indicated that 3.3 km mesh ICON (ICON_3.3 km) exhibited notable added value in simulating the spring atmospheric water cycle over the TP. ICON_3.3 km reduced the wet biases of precipitation in the ERA5 reanalysis and 13.2 km mesh ICON (ICON_13.2 km) simulations, and improved the simulation of surface evaporation over the central and eastern TP. The reduction in the simulated precipitation in ICON_3.3 km was primarily followed by a decrease in surface evaporation from March to May, second by a reduction in water vapor flux convergence in May due to decreased water vapor inflow from the southeastern TP. Furthermore, compared to ICON_13.2 km, ICON_3.3 km alleviated the “drizzling” bias, leading to drier surface soils and decreased evaporation, and lead to 3% decrease in the fraction of evaporation converted into precipitation. Sensitivity experiments conducted at resolution of 13.2 km but turning off the convection parameterization demonstrated that both explicit representation of convection and enhanced horizontal resolution were crucial for accurately representing the spring atmospheric water cycle over the TP. Our results highlighted the need to develop kilometer‐scale models for successfully reproducing the climate characteristics across the TP.

Analysis of Precipitable Water Vapor, Liquid Water Path and Their Variations before Rainfall Event over Northeastern Tibetan Plateau

A ground-based microwave radiometer (MWR) provides continuous atmospheric profiles under various weather conditions. The change in total precipitable water vapor (PWV) and liquid water path (LWP) before rainfall events is particularly important for the improvement in the rainfall forecast. However, the analysis of the PWV and LWP before rainfall event on the plateau is especially worth exploring. In this study, the MWR installed at Xining, a city located over the northeastern Tibetan Plateau, was employed during September 2021 to August 2022. The results reveal that the MWR-retrieved temperature and vapor density demonstrate reliable accuracy, when compared with radiosonde observations; PWV and LWP values during the summer account for over 70% of the annual totals in the Xining area; both PWV and LWP at the initiating time of rainfall events are higher during summer, especially after sunset (during 20-00 local solar time); and notably, PWV and LWP anomalies are enhanced abruptly 8 and 28 min prior to the initiating time, respectively. Furthermore, the mean of LWP anomaly rises after the turning time (the moment rises abruptly) to the initiating time; as the intensity of rainfall events increases, the occurrence of the turning time is delayed, especially for PWV anomalies; while the occurrence of the turning time is similar for both convective cloud and stratiform cloud rainfall events, the PWV and LWP anomalies jump more the initiating time; as the intensity of rainfall events increases, the occurrence of the turning time is delayed, especially for PWV anomalies; while the occurrence of the turning time is similar for both convective cloud and stratiform cloud rainfall events, the PWV and LWP anomalies jump more dramatically after the turning time in convective cloud events. This study aims are to analyze the temporal characteristics of PWV and LWP, and assess their potential in predicting rainfall event.

Assessing the Radon Exposure Variability and Lifetime Health Effects across Indoor Microenvironments and Sub-Populations

To assess the health impacts of radon exposure over a lifetime, in the present study, the annual effective dose (AED) and cumulative excess lifetime cancer risk (ELCR-C) were evaluated by considering various indoor microenvironmental exposures based on age-specific time–activity patterns using Monte Carlo simulations. Significant regional variations in indoor radon concentrations across the Republic of Korea were observed, with the highest levels found in schools and single detached houses. Based on the standard annual total of 8760 h spent indoors and outdoors, the AED varied by age group and dwelling type, with the ELCR-C for single detached houses being approximately 1.36 times higher than that for apartments on average. The present study highlights the importance of comprehensive health risk assessments that consider differences across indoor environments and age groups, indicating that limited evaluations of specific sites or areas may distort actual exposure levels.

Temporal trends and regional variations in operative vaginal deliveries in Japan: A national representative cohort study.

To analyze temporal trends and regional variations in operative vaginal delivery (OVD) in Japan. Using the National Database of Health Insurance Claims and Specific Health Checkups of Japan from 2014 to 2021, we identified the numbers of vacuum and forceps deliveries. We analyzed annual totals and proportions of OVDs and calculated the mean age of women undergoing these deliveries. We also predicted trends in OVD for the next 20 years and compared geographical differences in the proportions of forceps deliveries among OVDs. During the observation period, out of 7 368 814 total births, 8.4% were through OVD, including 7.6% by vacuum and 0.8% by forceps. Both delivery methods showed an increasing trend from 2014 to 2021: vacuum deliveries rose from 7.0% to 8.7%, and forceps deliveries increased from 0.6% to 1.0%. Notably, the proportion of forceps deliveries in OVD increased from 8.1% to 10.5%. The mean age was higher for forceps deliveries than vacuum deliveries. According to our predictions, vacuum deliveries may continue to increase, but forceps deliveries may stabilize. The proportion of forceps deliveries among OVDs ranged from 0% to 38% across Japanese prefectures. This study shows an increase in the use of OVD in Japan from 2014 to 2021. There are large regional differences in the choice between vacuum and forceps deliveries. These findings can help us understand the practice of OVD in Japan.

Seasonal precipitation distribution determines ecosystem CO2 and H2O exchange by regulating spring soil water–salt dynamics in a brackish wetland

Abstract The intensification of the global hydrological cycle is anticipated to increase the variability of precipitation patterns. Brackish wetlands respond to changes in precipitation patterns by regulating the absorption and release of CO2 and H2O to maintain the stability of ecosystem functions. However, there is limited understanding of how the inter‐seasonal precipitation distribution (SPD) affects ecosystem CO2 and H2O exchange compared with annual precipitation totals. Here, we conducted four consecutive years of field experiments in a brackish wetland, manipulating the proportion of precipitation across different seasons while maintaining a constant annual precipitation total. We utilized five inter‐SPD proportions (+73%, +56%, control (CK), −56%, −73%) to examine the effects of SPD on ecosystem CO2 and H2O exchange. Our findings revealed that the annual ecosystem CO2 and H2O fluxes showed a trend of decreasing with the decrease in spring precipitation distribution. Among them, the annual net ecosystem CO2 exchange, evapotranspiration, carbon use efficiency and water use efficiency were shown to be more sensitive to decrease in spring precipitation distribution and increase in summer and autumn precipitation distribution. This negative asymmetric response pattern suggests that annual ecosystem CO2 and H2O exchange is primarily governed by seasonal precipitation variability, with spring soil water–salt dynamics identified as the key driver. Therefore, this association can be explained by the fact that drought of the early growth stage exacerbates soil salinization and inhibits vegetation colonization and growth, thereby greatly impairing the annual CO2–H2O exchange capacity of brackish wetlands. Our results emphasized that the spring extreme precipitation‐induced soil water–salt conditions will greatly influence CO2 and H2O exchange in brackish wetlands in the future. These findings are crucial for improving predictions of the carbon sequestration and water‐holding capacity of brackish wetlands. Read the free Plain Language Summary for this article on the Journal blog.

Developing a solar PV system for cost-effective electricity reduction in an aluminium extrusion plant

Abstract The demand for solar photovoltaic systems has been steadily increasing over the years, driven by the collective goal to reduce both CO2 emissions and electricity bills in order to foster a sustainable world. Industries with high energy consumption, particularly manufacturing, are actively pursuing the establishment of more sustainable plants to align with net-zero objectives. The primary aim of this project is to design a solar photovoltaic system tailored for an aluminium manufacturing plant, with the intent to curtail electricity consumption and minimize CO2 emissions by harnessing and utilizing energy generated from the photovoltaic system. The comprehensive analysis encompasses meteorological data, daily load demand configuration, photovoltaic array assessment, and simulation of grid-connected inverter sizing through the utilization of PVsyst software. According to the simulation results, the collective operational capacity of the solar photovoltaic system reaches 5240 kWp, effectively meeting 85% of the factory’s maximum demand. To fulfil the plant’s requirements, a total of 12780 panels are necessary. The analysis reveals that this solar system can generate a total of 7,609,690 kWh annually, constituting approximately 26.10% of the total electricity bill for the year 2022, amounting to 29,146,841.28 kWh. The estimated savings from implementing this solar solution amount to around RM 2,701,518 per year. Moreover, the solar system significantly reduces CO2 emissions by an annual total of 4,224.467 tons, contributing to a healthier surrounding environment. The anticipated return on investment, as per the PVsyst projections, is expected to occur within approximately 3.4 years.

Hydropower capacity factors trending down in the United States

The United States hydropower fleet has faced increasing environmental and regulatory pressures over the last half century, potentially constraining total generation. Here we show that annual capacity factor has declined at four fifths of United States hydropower plants since 1980, with two thirds of decreasing trends significant at p < 0.05. Results are based on an analysis of annual energy generation totals and nameplate capacities for 610 plants (>5 megawatt), representing 87% of total conventional hydropower capacity in the United States. On aggregate, changes in capacity factor imply a fleetwide, cumulative generation decrease of 23% since 1980 before factoring in capacity upgrades—akin to retiring a Hoover Dam once every two to three years. Changes in water availability explain energy decline in only 21% of plants, highlighting the importance of non-climatic drivers of generation, including deterioration of plant equipment as well as changes to dam operations in support of nonpower objectives.

Assessment of the impact of observations at Nainital (India) and Comilla (Bangladesh) on the CH4 flux inversion

Methane emission in South Asia is poorly understood due to a lack of observations, despite being a major contributor to methane emissions globally. We present the first results of atmospheric CH4 inversions using air samples collected weekly at Nainital, India (NTL), and Comilla, Bangladesh (CLA), in addition to surface background flask measurements by NOAA, CSIRO and AGAGE using the MIROC4-ACTM. Our simulations span from 2000 to 2020 (considering the fixed “edge” effect), but the main analysis period is 2013–2020, when both the NTL and CLA datasets are available. An additional flux uncertainty reduction of up to 40% was obtained (mainly in the northern part of the Indian subcontinent), which enhanced our confidence in flux estimation and reaffirmed the significance of observations at the NTL and CLA sites. Our estimated regional flux was 64.0 ± 4.7 Tg-CH4 yr−1 in South Asia for the period 2013–2020. We considered two combinations of a priori fluxes that represented different approaches for CH4 emission from rice fields and wetlands. By the inversion, the difference in emissions between these combinations was notably reduced due to the adjustment of the CH4 emission from the agriculture, oil and gas, and waste sectors. At the same time, the discrepancy in wetland emissions, approximately 8 Tg-CH4 yr−1, remained unchanged. In addition to adjusting the annual totals, the inclusion of NTL/CLA observations in the inversion analysis modified the seasonal cycle of total fluxes, possibly due to the agricultural sector. While the a priori fluxes consisted of a single peak in August, the a posteriori values indicated double peaks in May and September. These peaks are highly likely associated with field preparation for summer crops and emissions from rice fields during the heading stage (panicle formation). The newly incorporated sites primarily exhibit sensitivity to the Indo-Gangetic Plain subregion, while coverage in southern India remains limited. Expanding the observation network is necessary, with careful analysis of potential locations using back-trajectory methods for footprint evaluation.

Biomass Burning in Northeast China over Two Decades: Temporal Trends and Geographic Patterns

Despite the significant impacts of biomass burning (BB) on global climate change and regional air pollution, there is a relative lack of research on the temporal trends and geographic patterns of BB in Northeast China (NEC). This study investigates the spatial–temporal distribution of BB and its impact on the atmospheric environment in the NEC region during 2004 to 2023 based on remote sensing satellite data and reanalyzed data, using the Siegel’s Repeated Median Estimator and Mann–Kendall test for trend analysis, HDBSCAN to identify significant BB change regions, and Moran’s Index to examine the spatial autocorrelation of BB. The obtained results indicate a fluctuating yet overall increasing BB trend, characterized by annual increases of 759 for fire point counts (FPC) and 12,000 MW for fire radiated power (FRP). BB predominantly occurs in the Songnen Plain (SNP), Sanjiang Plain (SJP), Liaohe Plain (LHP), and the transitional area between SNP and the adjacent Greater Khingan Mountains (GKM) and Lesser Khingan Mountains (LKM). Cropland and urban areas exhibit the highest growth in BB trends, each surpassing 60% (p &lt; 0.05), with the most significant growth cluster spanning 68,634.9 km2. Seasonal analysis shows that BB peaks in spring and autumn, with spring experiencing the highest severity. The most critical periods for BB are March–April and October–November, during which FPC and FRP contribute to over 80% of the annual total. This trend correlates with spring planting and autumn harvesting, where cropland FPC constitutes 71% of all land-cover types involved in BB. Comparative analysis of the aerosol extinction coefficient (AEC) between areas with increasing and decreasing BB indicates higher AEC in BB increasing regions, especially in spring, with the vertical transport of BB reaching up to 1.5 km. County-level spatial autocorrelation analysis indicates high–high clustering in the SNP and SJP, with a notable resurgence of autocorrelation in the SNP, suggesting the need for coordinated provincial prevention and control efforts. Finally, our analysis of the impact of BB on atmospheric pollutants shows that there is a correlation between FRP and pollutants, with correlations for PM2.5, PM10, and CO of 0.4, 0.4, and 0.5, respectively. In addition, the impacts of BB vary by region and season, with the most significant impacts occurring in the spring, especially in the SNP, which requires more attention. In summary, considering the escalating BB trend in NEC and its significant effect on air quality, this study highlights the urgent necessity for improved monitoring and strategic interventions.

Applicability of a radiant-capacitive cooling and heating system in its cooling mode in Köppen-Geiger's A, B and C climate types

This study presents indoor temperature predictions of a novel radiant-capacitive cooling and heating system developed and tested in its cooling mode for ten locations within the latitude range 37.42°N and 12.4°S with annual Cooling Degree-Days (CDD, using the upper limit of the adaptive comfort range as base temperature) ranging between 657 and 1818 CDD. The system was tested experimentally in Curitiba, Brazil. Based on field data, predictive formulas were generated for the minimum, average and maximum indoor temperatures solely using outdoor temperatures as predictors. The aim was to assess the cooling potential and system performance of system in locations with climate types distinct from Curitiba's. The night-time radiative cooling potential was evaluated in each city in terms of sky temperature depression (DTsky, given in Kelvin-hour, Kh). The annual totals of DTsky ranged between 270 Kh and 2269 Kh for the evaluated cities. The system's performance was assessed in terms of offsets of the maximum and average indoor temperature relative to outdoors, and of percent reductions in CDD. Indoor temperature depressions reach mean values of up to 5.7 K and 5.8 K in cities with the highest nocturnal radiative cooling potentials, while the lowest average temperature depressions were observed in locations with the lowest cooling potential. Results show potential reductions of the indoor average temperature ranging between 1.3 K and 2.2 K, with a corresponding CDD offset ranging between 72.1 % and 95.3 %.