Atmosphere

Sea fog poses a considerable challenge to port operations, impacting maritime safety and efficiency. During the past five years, the average annual downtime of the navigation dispatch department in Ningbo Zhoushan Port due to weather was 800–1000 h, of which approximately 300 h can be attributed to sea fog. This study addresses the issue by developing a comprehensive sea fog monitoring system for Ningbo Zhoushan Port. The system utilizes automatic weather stations (AWS) and visibility laser imaging, detection, and ranging (LIDAR) to assess sea fog severity and improve monitoring accuracy. By increasing monitoring frequency and adopting corresponding warning measures, the system aims to enhance maritime safety and efficiency in Ningbo Zhoushan Port. The results showed that the implemented system successfully determines sea fog severity, enables real-time monitoring, and provides precise visibility assessments. Joint assessments revealed a substantial increase in the annual operating time and revenue of the port. These findings underscore the importance of advanced monitoring techniques in optimizing port operations, reducing collision risks, and mitigating economic losses caused by sea fog. Full article

The present study investigated the cooling effect of extensive green roofs and green façades, at the pedestrian level, of a Mediterranean densely populated neighborhood. The ENVI-met environmental model was employed to simulate the microclimatic environment on a typical summer day. Thermal conditions of the study area were evaluated based on air temperature and the Mediterranean thermal stress scale of UTCI (Universal Thermal Climate Index). Three mitigation strategies were developed to ameliorate the thermal conditions in the examined area focusing on the efficacy of green façades, green roofs, and the synergetic effect of the green façade and green roof. The mitigation strategies’ performance was evaluated in characteristic design layouts of the study area, namely the following: a typical Mediterranean square, a church with a churchyard, an avenue, NS and EW street orientations, and courtyards. Results showed that compared to the existing configuration, the synergetic effect of the green façade and green roof achieved the greatest amelioration of the thermal conditions during the hottest hours of the day (12:00–18:00) since it produced an average Tair reduction of up to 0.7 °C and a UTCI reduction of 1.6 °C (both in the courtyards design layout). Among the examined design layouts, the courtyards produced the greatest reductions in air temperature and UTCI, whereas the EW streets were the lowest. Full article

The Atacama desert stands as the most arid, non-polar, region on Earth and has accommodated a considerable portion of the world’s ground-based astronomical observatories for an extended period. The comprehension of factors important for observational conditions in this region, and the potential alterations induced by the escalating impact of climate change, are, therefore, of the utmost significance. In this study, we conduct an analysis of the surface-level air temperature, water vapour density, and astronomical seeing at the European Southern Observatory (commonly known by its acronym, ESO) telescope sites in northern Chile. Our findings reveal a discernible rise in temperature across all sites during the last decade. Moreover, we establish a correlation between the air temperature and water vapour density with the El Niño Southern Oscillation (ENSO) phases, wherein, the warm anomaly known as El Niño (EN) corresponds to drier observing conditions, coupled with higher maximum daily temperatures favouring more challenging near-infrared observations. The outcomes of this investigation have potential implications for the enhancement of the long-term scheduling of observations at telescope sites in northern Chile, thereby aiding in better planning and allocation of resources for the astronomy community. Full article

The excessive consumption of fossil fuels has resulted in massive carbon emissions and serious ecological and environmental crises. Therefore, achieving the efficient utilization of waste carbon sources is considered as an important pathway to addressing the aforementioned issues in the context of carbon neutrality. Developing and designing suitable catalyst materials has become the key to converting CO_x into valuable platform chemicals and value-added liquid fuels (e.g., CO, CH₄, CH₃OH, and C₂₊ hydrocarbons). A moderate interaction between nitrogen-doped carbon materials and active metals is more favorable for the progress of the CO_x hydrogenation reaction compared to traditional metal oxide carriers. In this work, we comprehensively summarize the synthesis methods of N-doped carbon materials and the relevant research progress in the field of CO_x hydrogenation. In addition, a general assessment of carbon-based catalysts for CO_x hydrogenation reactions, concerning the support and metal properties, the activity and product selectivity, and their interactions is systematically discussed. Finally, this review discusses the roles of N-doped carbon materials, the current challenges, and future development directions. Full article

The vibrating mesh nebulizer (VMN) has gained popularity for its compactness and noiselessness. This study investigates the impact of different air inlet structures on the deposition fraction (DF) of droplets generated by VMNs in an idealized mouth–throat (MT) airway model. Three homemade VMNs with semi-circular inlet, symmetrical four-inlet, and multiple-orifice inlet structures were evaluated through simulations and experiments. The changes in droplet DF of 0.9% w/v concentration of nebulized sodium chloride (NaCl) droplets as a function of inertial parameters were acquired under different inhalation flow conditions. Additionally, flow field distributions in models with different inlet structures were analyzed at a steady inspiratory flow rate of 15 L/min. The results indicate that optimizing the VMN’s air inlet structure significantly enhances droplet delivery efficiency. The multiple–orifice inlet structure outperformed the other designs, directing the airflow from the inlet position to the center of the mouthpiece and then into the oral cavity, achieving a DF of up to 20% at an inhalation flow rate of 15 L/min. The region of high airflow velocity between the mouthpiece and oral cavity proved to be a favorable VMN inlet optimization, reducing direct droplet–wall collisions and improving delivery efficiency. These findings offer insights for VMN design and optimization to enhance pulmonary drug delivery effectiveness and therapeutic outcomes. Full article

Practical application has shown that the blown-up theory has great predictive ability for predicting transitional weather systems, especially catastrophic weather systems. This study applies the blown-up theory to analyze and predict a rainstorm case in Jiangsu Province of East China to explore the applicability of the blown-up theory. At the same time, a numerical simulation experiment is conducted using the Weather Research and Forecasting Model (WRF) v4.2. The numerical results are compared with the European Center for Medium Weather Forecasting (ECMWF) Reanalysis v5 (ERA5) data and the China Meteorological Administration (CMA) Land Data Assimilation System (CLDAS) products. It is found that there is a deviation in the simulation for the precipitation center, and further analysis indicates that it is likely related to the position of the simulated low-level shear line. On the other hand, the blown-up analyses are consistent with the actual situation and provide additional information besides the numerical simulation results. These results indicate that the blown-up charts and V-3θ diagrams are able to predict the weather system transformation, the rainfall area, and the evolution of the rainstorm, which confirms the applicability of the blown-up theory to rainstorm forecasts. This provides an auxiliary analysis method in addition to numerical simulations for rainstorm forecasts. Full article

We evaluated the detection efficiency and location accuracy of lightning discharges in Japan using Blitzortung.org, a volunteer-based network for locating lightning discharges from sferics measured by very low frequency (VLF) electromagnetic receivers that have been deployed worldwide in recent years. A comparison of the flash rate (the detected lightning rate per area and period) from Blitzortung.org with that from the satellite-based OTD/LIS and the ground-based World Wide Lightning Location Network (WWLLN) observations showed that Blitzortung.org clearly observed intense lightning activity in and around the Kanto area, including Tokyo, in summer, which is typical of Japanese lightning activity. However, it did not clearly observe lightning activity in and around the Nansei Islands, including Okinawa. Conversely, Blitzortung.org observed winter lightning activity in the Hokuriku area and off the Kanto. In addition, event studies have compared the detection efficiency and location accuracy of Blitzortung.org with those of the Japanese Lightning Location Network (JLDN) to infer their absolute values. The latest detection efficiency of Blitzortung.org in the Kanto area was estimated at roughly 90%. The mean location accuracy was estimated at up to 5.6 km. Full article

In subtropical regions, heavy rains from cumulonimbus clouds can cause disasters such as flash floods and mudslides. The accurate prediction of cumulonimbus cloud distribution is crucial for mitigating such losses. Traditional machine learning approaches have been used on radar echo data generated by constant altitude plan position indicator (CAPPI) radar systems for predicting cumulonimbus cloud distribution. However, the results are often too foggy and fuzzy. This paper proposes a novel approach that integrates graph convolutional networks (GCN) and trajectory gated recurrent units (TrajGRU) with an attention mechanism to predict cumulonimbus cloud distribution from radar echo data. Experiments were conducted using the moving modified National Institute of Standards and Technology (moving MNIST) dataset and real-world radar echo data, and the proposed model showed a 59.12% improvement in mean square error (MSE) and a 16.26% improvement in structure similarity index measure (SSIM) on average in the moving MNIST dataset, a 65.40% improvement in MSE, and an 10.29% improvement in SSIM on average in the radar echo dataset. These results demonstrate the effectiveness of the proposed approach for improving the prediction accuracy of cumulonimbus cloud distribution. Full article

A typhoon is a severe weather process in tropical oceans. Typhoon transit is often accompanied by strong convective weather, such as gales and rainstorms, which threatens fishery, property, and human safety. In this study, the effects of typhoon Chanthu on chlorophyll a (Chl a), temperature, and ocean surface salinity are analyzed using remote sensing data. The results illustrate that before the transit of Chanthu (6–12 September), the mean concentration of Chl a and sea surface salinity (SSS) are low (0.74 mg/m³, 30.59 psu, respectively), while the mean sea surface temperature (SST) is high (29.01 °C). After the typhoon transits (13–30 September), the mean Chl a concentration and salinity increase (1.29 mg/m³, 30.87 psu respectively), while the mean SST decrease (27.43 °C). The Ekman pumping transports nutrients from the deep ocean to the surface layer, promotes the photosynthesis of surface phytoplankton, and increases the concentration of sea surface Chl a. Typhoon Chanthu causes the mixing and entrainment of the upper ocean, which causes the deep cold water of the ocean to rise into the mixed layer and cause the SST to decrease. Severe vertical mixing transports deep high-salt water to the surface, causing SSS to rise. The results of this study have important scientific significance and application value for developing coastal economy, aquaculture, and fishery. Full article

The in-traffic microenvironment can enhance personal exposure to fine particulate matter (PM). With this study, we aimed to calibrate a DustTrak instrument (DustTrak 8533 DRX Aerosol Monitor, TSI Incorporated, Shoreview, MN, USA) and low-cost sensors (AS-LUNG-P sensors) and then assess inhalation exposure to PM_2.5 and PM₁ for different commuters in central areas of Ho Chi Minh City (HCM). The DustTrak instrument and low-cost sensors were calibrated using a gravimetric method under side-by-side conditions. Relationships between the DustTrak signals and PM concentrations measured by the gravimetric method were identified using simple linear regression models for PM_2.5 (R² = 0.998, p-value < 0.05) and PM₁ (R² = 0.989, p-value < 0.05). Meanwhile, PM concentrations determined by the AS-LUNG-P sensors and the gravimetric method were correlated using two-segmented linear regressions. To obtain the corresponding two-segment regression equations, the response of the AS-LUNG-P sensors was compared with the corrected DustTrak data. The coefficient of variation (CV) evaluated for all sensors was smaller than 10%, indicating that the data were applicable for particle assessment. For inhalation exposure assessment, the results showed that commuters using open transport modes, such as bikes, motorbikes, and walking, were exposed to more PM than those using closed transport modes (e.g., cars). Specifically, the bicyclists had the highest inhaled doses of PM among the open transport groups. PM exposure levels in the morning were higher than in the afternoon. Additionally, exposure levels to PM concentrations rapidly increased when passing through intersections of major roads and moderately decreased when using surgical facemasks. Full article

The Three Gorges Reservoir area of the Yangtze River has formed vast riverine fallout zones as a result of its periodic water storage and flood discharge operations, and the main constituents of this area are quaternary loose clays. It is important to study the microscopic characteristics of clay minerals in these fallout zones and their adsorption properties of Hg²⁺ to guide the environmental safety of the fallout zones in the Three Gorges Reservoir area. In this context, the authors of this paper used X-ray diffraction (XRD) experiments to reveal the main clay mineral compositions in the fallout zones and then constructed the molecular model structures of the clay minerals based on molecular dynamics theory and studied the adsorption characteristics of these clay minerals with Hg²⁺ in depth. The results show that the main clay minerals in the Three Gorges Reservoir area fallout zone include illite, illite-mixed layer and green-mixed layer, in which the content of illite ranges from 21% to 54%. Taking illite as the study object, the heat of adsorption of Hg²⁺ in illite ranged from 14.83 kJ·mol⁻¹ to 31.92 kJ·mol⁻¹, which is a physical adsorption. The heat of adsorption was mainly affected by the water content and had little relationship with temperature. With the gradual increase in water content, the heat of adsorption gradually decreases. The adsorption amount of Hg²⁺, on the other hand, is jointly affected by water content and temperature and decreases with the increase in water content and temperature; under natural environmental conditions (P = 0.1 Mpa), the adsorption characteristics of Hg²⁺ in illite change with the change in water content. When the water content was between 0% and 6.95%, the increase in water content led to an increase in the interlayer spacing of illite, and the adsorption of Hg²⁺ in illite was in a monolayer state, with the adsorption peaks located from 4.5~5.5 Å. When the water content increased to 6.95% to 13.90%, the layer spacing of illite reached the maximum, and the adsorption of Hg²⁺ in illite transitioned from a monolayer to a bilayer, with the adsorption peaks located between 5 Å and 9~10 Å, respectively. When the water content was further increased to 13.90% to 20.85%, the increase in water content instead led to a slight decrease in the layer spacing of illite, showing a tendency of transitioning from a bilayer to a monolayer adsorption layer, which at the same time changed the number of adsorption layers of Hg²⁺; the study also revealed that the interaction between illite and Hg²⁺ was regulated by van der Waals and Coulomb forces, whereas the increase in temperature promoted the Hg²⁺ +diffusion, and an increase in water content inhibits the diffusion of Hg²⁺. In summary, these findings provide valuable theoretical support for solving the problem of Hg²⁺ pollution in the Three Gorges Reservoir Decline Zone. Full article

In order to explore the possible impact of topography on precipitation between the eastern and western sides of the Liupan Mountains (LMs) in the northwest region of China, the differences in distribution characteristics of total column water vapor (TCWV), total column cloud water (TCCW), and total precipitation (TP) were studied by using the 40-year hourly data of the fifth generation reanalysis (ERA5) from the European Centre for Medium-Range Weather Forecasts (ECMWF). The results showed the following: (1) The TCCW and TP on the eastern and western sides of the LMs decrease gradually from south to north, following a southwestward bias along the latitude. The high values of the TCCW and TP are predominantly concentrated in the period from July to September. The greatest difference between the two sides occurs in September, with the eastern side exhibiting 15% and 18% higher values compared to the western side, respectively. (2) Both the TCCW and TP exhibit distinct diurnal distribution patterns. The high values on the eastern side persist for a longer duration throughout the day compared to the western side, and they occur in more consecutive months. There is a certain correlation between the steepness of the eastern slope and the gentle gradient of the western slope. Additionally, the occurrence of these high values in the afternoon is earlier on the eastern side compared to the western side. (3) The monthly mean TP is significantly linearly correlated with the TCWV and TCCW, with slightly higher coefficients for the western side compared to the eastern side. This relationship is closely related to the topography of the mountain range. The regression equation provides a quantitative tool for predicting the monthly mean TP in the LM region and serves as a reference basis for the development of cloud water resources in the area. Full article

In the recent past, Andhra Pradesh (AP) has experienced increasing trends in surface air mean temperature (SAT at a height of 2 m) because of climate change. In this paper, we attempt to estimate the SAT using the GFDL-ESM2G (Geophysical Fluid Dynamics Laboratory Earth System Model version 2G), available from the Coupled Model Intercomparison Project Phase-5 (CMIP5). This model has a mismatch with the India Meteorological Department (IMD)’s observations during April and May, which are the most heat-prone months in the state. Hence, in addition to the SAT from the model, the present paper considers other parameters, such as mean sea level pressure, surface winds, surface relative humidity, and surface solar radiation downwards, that have influenced the SAT. Since all five meteorological parameters from the GFDL-ESM2G model influence the IMD’s SAT, an artificial neural network (ANN) technique has been used to predict the SAT using the above five meteorological parameters as predictors (input) and the IMD’s SAT as the predictand (output). The model was developed using 1981–2020 data with different time lags, and results were tested for 2021 and 2022 in addition to the random testing conducted for 1981–2020. The statistical parameters between the IMD observations and the ANN estimations using GFDL-ESM2G predictions as input confirm that the SAT can be estimated accurately as described in the analysis section. The analysis conducted for different regions of AP reveals that the diurnal variations of SAT in the IMD observations and the ANN predictions over three regions (North, Central, and South AP) and overall AP compare well, with root mean square error varying between 0.97 °C and 1.33 °C. Thus, the SAT predictions provided in the GFDL-ESM2G model simulations could be improved statistically by using the ANN technique over the AP region. Full article

Surface waves and sea spray play a significant role in air–sea fluxes in high winds. The present study used a marine atmosphere surface layer (MASL), which couples the traditional Monin–Obukhov similarity theory, sea spray generation function, the balance of turbulent kinetic budget, and momentum/enthalpy conservation equations. Based on this model, the effects of wave states and spray injection velocities on air–sea momentum/enthalpy fluxes and near-surface wind/temperature profiles were theoretically investigated. Based on the assumption that the velocity of injected spray is the same as that of the ambient airflow, it was found that spray could increase the near-surface air turbulence intensity and inhibit air–sea fluxes at 10 m above the sea surface. Correspondingly, near-surface wind speeds and temperature increase in high winds. This phenomenon becomes prominent in cases of large wave ages or surface waves supporting a minority of air–sea fluxes. Based on the assumption that the velocity of the edges of breaking water bags is used to estimate that of spray injection, the opposite results were found: spray could weaken the near-surface air turbulence and increase total air–sea fluxes at 10 m above the sea surface. In this case, the near-surface wind speeds and temperature decreased. This reduction becomes remarkable when surface waves are full-developed or the majority of air–sea momentum fluxes are supported by waves. Full article

Anthropogenic heat (AH) emissions have great impacts on urban climate. AH is usually spatially heterogeneous and depends on the urban land use type. Studies using high-resolution gridded data that can resolve spatially heterogeneous AH are still scarce. The present study uses AH data of a high spatial resolution of 200 m by 200 m and a temporal resolution of 1 h to investigate the impact of AH in Singapore in April 2016, particularly regarding the relative contribution of individual AH components. The WRF model coupled with a single-layer urban canopy model is employed. The WRF model can predict the 2-m air temperature and 2-m relative humidity with good agreement with the observation data, while the simulated 10-m wind speed has relatively large deviation from the observation data. The largest spatially averaged temperature increases caused by total AH (Q_F), AH from buildings (Q_B) and AH from traffic (Q_V) are 1.44 °C, 1.44 °C and 1.35 °C, respectively. The effects of AH on sensible heat flux and boundary layer height are largely consistent, with both Q_F and Q_B exhibiting significant effects at night, while the effects of Q_V are small. The effect of AH on the local circulations (sea and land breezes) in Singapore is small, while its effect on the urban heat island (UHI) circulations is more pronounced. Due to the UHI circulations, the sum of the effects on local temperatures caused by Q_B and Q_V may exceed that by Q_F in some areas. This finding can guide comprehensive mitigation measures of AH by not only focusing on land use type but also on the contribution of individual AH components, in order to ameliorate the impacts of urban overheating. Full article

Rising summer temperatures lead to heat waves and tropical nights, which can result in health problems among the population. This work examined if mortality among Viennese people has increased under such weather conditions or whether the population was able to adapt to those periods of extreme heat. Therefore, the daily climatic data of the Austrian Weather Service and the number of daily deaths in Vienna from 1998 to 2022 have been put into relation. After calculating the mean values from those data sets, we analyzed the total number of daily deaths but also the death rate per 100,000 inhabitants for the total Viennese population, for men and women. The impact of age structure on possible trends was analyzed and ruled out. The analysis showed that the mortality on days with heat events was still higher, but the mean values of daily deaths decreased over time, despite a doubling of heatwaves and tropical nights, which speaks for an adaptation to heat events by the Viennese population. Full article

This study aimed to assess the performance of 35 global climate models included in NEX-GDDP-CMIP6, derived from downscaling CMIP6 data to high spatial (25 km) and temporal (daily) resolutions, in reproducing extreme precipitation events over the Huai River Basin. Eight widely used extreme precipitation indices were employed to quantitatively describe the models’ capability of simulation. Results indicate that the majority of models can reasonably capture trends, with UKESM1-0-LL performing the best among all considered models. All models demonstrate high accuracy in simulating climatological means, especially for the total precipitation (PRCPTOT), displaying a spatial correlation coefficient exceeding 0.8 when compared to the observed data. NorESM2-MM and MRI-ESM2-0 can accurately simulate the frequency and intensity of extreme precipitation, respectively. In general, UKESM1-0-LL, CESM2, MIROC6, MRI-ESM2-0, CMCC-CM2-SR5, and MPI-ESM-2-LR exhibit superior simulation capabilities in terms of capturing both the trends and climatology of extreme precipitation. The aforementioned findings provide guidance for future studies on the regional impacts of climate change using NEX model data, and therefore hold great importance in comprehending the regional impacts of, and the adaptability to, climate change, as well as the development of adaptation strategies. Full article

Air quality is a prevalent concern due to its imposing health risks. The state of Utah, USA, at times over the last 20 years has suffered from some of the worst air quality in the nation. The propensity for the state of Utah to experience elevated concentrations of particulate matter and ozone can in part be attributed to its unique geography that features dry, mountainous topography. Valleys in Utah create ideal environments for extended cold-pool events. In this review, we summarize the research executed in Utah over the past 20 years (2002–2022) by dividing the state into six regions: Utah Valley, Summit County, Southern Utah (regions south of Utah Valley), Cache Valley, Uinta Basin, and Salt Lake Valley. We review the published literature chronologically and provide a summary of each region identifying areas where additional research is warranted. We found that the research effort is weighted towards Uinta Basin and Salt Lake Valley, with the other regions in Utah only adding up to 20% of the research effort. We identified a need for more source apportionment studies, speciated volatile organic compound (VOC) studies, and ozone isopleths. Where ozone isopleths are not able to be created, measurement of glyoxal and formaldehyde concentrations could serve as surrogates for more expensive studies to inform ozone mitigation policies. Full article

Pesticides registered with the U.S. EPA for mosquito control are called adulticides and are released directly into the atmosphere as aerosols to target flying mosquitos. This adulticide application approach is different from traditional (agricultural) pesticide applications, yet the fate and transport of adulticides in large metropolitan areas is largely unknown. The Houston Metropolitan Area encompasses eight counties, many of which require county-level mosquito control programs that utilize adulticides. Malathion and permethrin are the primary adulticides used by Harris County (HC) in Houston, TX, USA. Houston, like many other metropolitan areas, has an urban atmosphere supporting the oxidation of both gas and particle phase pollutants. During the summer mosquito season of 2016, we collected atmospheric total suspended particulate matter (PM) samples at Jones Forest (JF), located in Montgomery County (directly north of HC) to investigate the atmospheric transport and oxidation of adulticides in an urban atmosphere. Despite HC alternating the adulticide treatment schedule, we measured permethrin, malathion, and malaoxon (oxidation product of malathion), throughout the sampling campaign. These consistent measurements, in conjunction with 12 h backward trajectories, support the conclusion that JF is influenced by other county-level mosquito-control programs and agricultural pesticide use. This cross-county transport may impact adulticide effectiveness by supporting pesticide resistance in mosquito populations due to repeated exposures to pesticides. This study highlights the need for mosquito control collaborations between counties, especially in areas of urban expansion overlapping with agricultural activities. Full article