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Background: Numerous studies showed an effect of weather on physical activity (PA) levels in children. However, no study has yet examined the relevance of personal factors in this relationship. Therefore, this study analyzes (1) whether there are systematic interindividual differences in the extent to which weather affects the PA behavior and (2) whether physical literacy (PL) moderates the weather–PA association in children. Methods: A total of 951 children in 12 Danish schools (age 9.76 [1.59] y; 54.3% girls) completed objective PA assessments via accelerometry (moderate to vigorous PA, light PA, and sedentary behavior). Local weather data (precipitation, wind speed, temperature, and sunshine duration) were provided by the Danish Meteorological Institute. Participants' PL was measured employing the Danish version of the Canadian Assessment of Physical Literacy-2. The 4116 accelerometer days underwent longitudinal multilevel analyses while considering their nesting into pupils and school classes (n = 51). Results: Fluctuations in all PA indicators were significantly explained by variations in weather conditions, especially precipitation (P ≤.035). Significant interindividual differences were found for 9 of 12 analytical dimensions, suggesting that weather changes influence PA behavior differently across individuals (especially moderate to vigorous PA, χ2[4] ≥ 11.5, P ≤.021). However, PL moderated the relationship between weather and PA in only 2 of the 48 analytical constellations. Conclusions: Despite the varying impact of weather on PA across individuals, the present study favors a main effect model in which weather and PL exert independent effects on children's PA. The insufficient support for PL as a moderating factor calls for future studies to test alternative mechanisms in the weather–PA association. [ABSTRACT FROM AUTHOR]

A joint maintenance decision-making framework is proposed to optimise the long-term maintenance plan and lower the maintenance cost for offshore wind farms. The historical wind speed data are screened by using the method of k-means clustering, and Markov chains are established for the wind speed in different seasons. On this basis, the approach of Markov chain Monte Carlo is applied to simulate the distribution of repair vessel's waiting time for maintenance, where the impact of wind speed on maintenance availability is considered. Moreover, the components in wind turbines are divided into four states according to their effective ages, i.e. young, mature, old and failed, respectively. A maintenance decision model is established, with the objective to minimise maintenance cost. Besides, three types of opportunistic maintenance are considered, i.e. failure-based opportunistic maintenance (FBOM), event-based opportunistic maintenance (EBOM) and age-based opportunistic maintenance (ABOM), respectively. The enhanced elitist genetic algorithm (SEGA) is adopted to solve the optimisation problem. The results indicate that among the three types of opportunistic maintenance, ABOM can reduce maintenance cost more effectively, and it is more suitable for long-term maintenance plans of offshore wind farm. [ABSTRACT FROM AUTHOR]

The quantum well diode (QWD) performs a dual role, functioning both as an emitter and a detector due to its unique feature of spectral overlap between emission and detection spectra. This dual functionality positions QWDs as promising candidates in the realm of multifunctional sensors. Furthermore, the well-established maturity of optical fiber communication, grounded in its intrinsic property of total reflection, makes it an ideal transmission medium for QWD sensing signals. Leveraging the coexisting emission and detection capabilities of QWDs, we have constructed a sensing system in this article. This system utilizes a QWD, which is stimulated to emit light, with the emitted light traveling through a specified length of optical fiber. A specialized load-bearing film, featuring an aluminum membrane on its rear to act as a mirror and an object of known weight on its front, induces deformation in the film, thereby altering the characteristics of the reflected light. This modulated light is subsequently captured by the QWD via the optical fiber, enabling the computation of the weight of the object. In this article, the QWD's emission peak is around 522 nm, and its detection range extends from 370 to 530 nm. Furthermore, by employing the appropriate approach, integrating QWD with optical fibers can be extended to sensing and measuring various physical quantities such as temperature, solution concentration, wind speed, and more. The advantages of QWDs include cost-effectiveness, multifunctionality, portability, and environmental friendliness. This technology represents a promising avenue for sensor control in the era of the Internet of Things. [ABSTRACT FROM AUTHOR]

This paper explores the short-term effect of tropical cyclones on economic activity at a local level in Madagascar. To do so, we combine high-resolution spatial data about nightlight brightness and exposure to tropical cyclones with geographic information at the smallest administrative level in Madagascar, namely the Fokontany. Our findings reveal that exposure to tropical cyclones leads to an ambiguous economic response as proxied by nocturnal brightness during the first year after the shock. However, during the second year, nightlights clearly increase, leading to an overall beneficial effect of 5% just 2 years after the tropical cyclone. We then provide a finer analysis by interacting wind speed exposure with variables that capture many heterogenous dimensions of our data. This analysis shows that for Fokontany sharing specific characteristics, the short-run effect of tropical cyclones is negative. However, the positive effect of exposure in the second year emerges as a regular pattern in our analysis. Our empirical study is in line with economic mechanisms suggesting that after a period of contraction, the impacted economy rebounds beyond the counterfactual trend that would otherwise be observed in the absence of a shock. [ABSTRACT FROM AUTHOR]

Dust records extracted from ice cores can facilitate the reconstruction of historical atmospheric dust levels and climate change. However, interpreting dust variations in ice cores is intricate because of the compounded influence of emission, transport, and deposition processes. This study investigated dust records retrieved from the Guliya ice cap drilled in 2015 on the West Tibetan Plateau using a mean trajectory transport and deposition model. Results showed that the Guliya dust concentration has exhibited a declining trend since the 1960s (−751 μg kg−1 yr−1). Applying an attribution approach, we discovered that low dust emission (80.3%) was the main cause of the drop in dust concentration, with changes related to transportation (5.2%) and deposition (14.5%) making only minor contributions. The weakening of surface wind speed in the desert and increasing precipitation in both the desert and glacier were the primary factors driving the decrease in Guliya dust concentration. Plain Language Summary: Dust emission, transport, and deposition processes are the key factors influencing the dust record in an ice core. Consequently, relying solely on ice core records may not be sufficient for the accurate reconstruction of past desertification processes and the evolution of the climate and environment. In this study, we endeavored to separate these complex processes from the Guliya ice core records on the Tibetan Plateau by integrating a transport model, thereby quantifying the impact of these processes on ice core records over the past 50 years. We found that the dust concentration changes in the Guliya ice core were primarily attributed to changes in dust emission strength, with a secondary influence of deposition and transport changes. This study can enhance the scientific interpretation of dust records preserved in ice cores, providing novel insights for a deeper comprehension of the climate and environmental evolution of the Tibetan Plateau. Key Points: The dust concentration in the Guliya ice core has decreased over the past 50 yearsThe decreasing trend of Guliya dust is primarily controlled by the emission process in the Taklimakan DesertThe principal drivers behind the reduction in Guliya dust were decreased surface wind speed and increased precipitation [ABSTRACT FROM AUTHOR]

Decadal variations in near‐surface wind speed (NSWS) and their causes are poorly understood. We found that the decadal transition of winter NSWS in northern China (NC) was 10 years earlier than in southern China (SC), which could be linked to the changes in intensities of the eastward wave‐activity flux and Siberian High (SH) induced by the Warm Arctic‐Cold Eurasia (WACE) dipole pattern. From 1973 to 1990, the WACE pattern from positive to negative phases confined the eastward wave trains to high latitudes with a decreasing SH, inducing an NSWS reduction. From 1991 to 2000, the WACE strengthened from negative to positive phases, causing a decadal transition in NSWS first in NC. After 2000, accompanied by the strengthening of the positive WACE, the eastward wave trains propagated downstream to lower latitudes, the SH and the meridional pressure gradient enhanced. Therefore, the transition of decadal NSWS occurred in SC until 2000. Plain Language Summary: Near‐surface wind speed (NSWS) is critical in exchanging energy, water, and momentum between the Earth's surface and the lower atmosphere. Previous studies have reported that the slowdown in NSWS and its reversal could be a manifestation of decadal variations in the climate system. However, the regional non‐synchronization of decadal variations in NSWS and the corresponding cause are poorly understood. This study reported a non‐synchronization of the decadal transition in winter NSWS between northern China (NC) and southern China (SC). The significant turning point of winter NSWS across NC was 10 years earlier than those across SC, and it was caused mainly by the zonal wind. The non‐synchronization of decadal variations in winter NSWS between NC and SC was linked to the Warm Arctic‐Cold Eurasia (WACE) atmospheric circulation pattern, and the Siberian High (SH) could serve as a bridge through which the WACE atmospheric circulation pattern influences the asynchronous transition of decadal NSWS between NC and SC. This study improves the understanding of decadal variations in NSWS across China. Key Points: The decadal near‐surface wind speed (NSWS) transition in winter over northern China (NC) was 10 years earlier than in southern China (SC)The non‐synchronization of the decadal transition in NSWS between NC and SC was linked with the Warm Arctic‐Cold Eurasia patternIntensities of wave‐activity flux and Siberian High influenced the non‐synchronization of decadal transition in NSWS between NC and SC [ABSTRACT FROM AUTHOR]

A radio link directly probing the inner solar corona offers the possibility to characterize solar wind properties, including velocity, density, turbulence, and even the axial ratio. In this study, we leveraged radiometric data obtained during a joint superior solar conjunction of the ESA/JAXA BepiColombo mission and the JAXA Akatsuki mission. Our objective is to ascertain the solar wind velocity by analysing Doppler-shift timeseries of radio signals exchanged between the two spacecraft and two distinct ground stations. We conducted a cross-correlation analysis to determine the travel time of large-scale plasma density fluctuations as they intersect with the downlink signals of both spacecraft. This method is applied to the data collected on 2021 March 13 and 2021 March 14. The analysis of the March 13 data has shown that the two Doppler residuals timeseries present a clear correlation at a time-lag of 2910 s. Using the knowledge of the relative distance between the two probe-ground station lines of sight at the closest approach to the Sun, we estimated the solar wind velocity to be |$421\pm 21$| km s−1. Following the same procedure for the second experiment, we estimated the solar wind speed velocity to be |$336\pm 7$| km s−1. These results are compatible with the sampling of the slow solar wind at heliographic latitudes of |$-22^\circ$| and |$-26^\circ$|⁠ , respectively. [ABSTRACT FROM AUTHOR]

Traditional computational fluid dynamics (CFD) methods used for wind field prediction can be time‐consuming, limiting architectural creativity in the early‐stage design process. Deep learning models have the potential to significantly speed up wind field prediction. This work introduces a convolutional neural network (CNN) approach based on the U‐Net architecture, to rapidly predict wind in simplified urban environments, representative of early‐stage design. The process of generating a wind field prediction at pedestrian level is reformulated from a 3D CFD simulation into a 2D image‐to‐image translation task, using the projected building heights as input. Testing on standard consumer hardware shows that our model can efficiently predict wind velocities in urban settings in less than 1 ms. Further tests on different configurations of the model, combined with a Pareto front analysis, helped identify the trade‐off between accuracy and computational efficiency. The fastest configuration is close to seven times faster, while having a relative loss, which is 1.8 times higher than the most accurate configuration. This CNN‐based approach provides a fast and efficient method for pedestrian wind comfort (PWC) analysis, potentially aiding in more efficient urban design processes. [ABSTRACT FROM AUTHOR]

The characteristics of 21 tropical cyclones (TCs) and associated high winds in Shanghai from 2005 to 2020 are analyzed based on the TC best track data, surface observations, and ERA5 reanalysis dataset. Results indicate that 95% of the TCs causing high winds in Shanghai were generated during July to September, and located to the south of Shanghai for ~80% of the impact time. Divided into four categories according to tracks, the TCs show significant discrepancies in genesis month and location, intensity, size, and duration. The findings of high winds in Shanghai highlight the combination effect of TC intensity, track, and the distance between TCs and Shanghai normalized by TC size (NDSH-TC). The maximum 10‐min sustained (Vmax) and extreme 3‐s wind speeds (Vex) in Shanghai only increase slightly with TC intensity, due to the fact that the stronger TCs are usually farther away from Shanghai. The Vmax and Vex differ in response to different TC tracks and reach the maximum value under TCs moving northward across the land west of Shanghai and the sea east of Shanghai, respectively. The urban and coastal wind speeds are the smallest and the largest respectively, indicating that the largest underlying surface roughness is associated with the most rapid urban construction. The wind speeds under the influence of TCs in four quadrants of Shanghai also present different variations with the NDSH-TC. Additionally, the wind direction in Shanghai is regularly related to the relative position between the TC center and Shanghai. A case study combined with TC In‐Fa (2106) verified the validity of the conclusions, which can provide a reference for TC forecasters to make more accurate wind field predictions. [ABSTRACT FROM AUTHOR]

Based on the daily temperature, wind speed, relative humidity, sunshine hours and precipitation in Sichuan Province from 1961 to 2022, the spatiotemporal variation characteristics of tourism climate comfort in Sichuan Province were analysed using the temperature–humidity index (THI), precipitation index (P), sunshine duration index (SSD), wind chill index (WCI) and tourism climate index (TCI). The results show that the average annual TCI in Sichuan Province over the past 62 years is “acceptable” or above and shows a significant increasing trend at a rate of 0.018 per decade. On average, the best travel comfort period in Sichuan Province is from March to May and from October to November. The TCI increased significantly in cold seasons such as February and November with rates of 0.064 and 0.053 per decade, respectively. The increase in TCI is mainly controlled by the increase in THI and WCI, both of which are related to the increase in temperature, with a greater effect in cold seasons and at higher elevations. Most of China's 5A‐level tourist attractions in Sichuan Province (14 of 17) have an annual TCI of “acceptable” or better. Similarly, the top 3 months for climate comfort at these attractions tend to be March to May and October, with ratings reaching “good” or even “very good.” For the other three destinations, all characterized by glaciers and mountains, the top 3 months for climate comfort are concentrated in the warm months. The overall tourism climate comfort of Sichuan Province is increasing, and the climate is changing in a positive way for the tourism industry. [ABSTRACT FROM AUTHOR]

Several damaging tropical cyclones (TCs) have occurred recently over the South Indian Ocean (SIO) region, causing enormous social and economic losses. Yet, while many studies have examined SIO TC characteristics using observations and reanalysis, only a few have assessed these characteristics specifically for this region in climate models, and fewer have investigated their projections under climate change. Here we do this for a historical (1980–2010) and future (2020–2050) period, using multimodel simulations from the High Resolution Model Intercomparison Project, as well as examine biases in the historical period relative to a reanalysis (ERA5). The models have horizontal resolutions of 25–50 km, which has enabled an improved ability to represent tropical cyclones globally in previous studies. TempestExtremes software is employed to detect tropical storm and cyclone tracks. In cases where TempestExtremes cannot be applied due to a lack of requisite variables in a dataset, we instead examine extreme wind speeds in that dataset. For the historical period, we find considerable variation in model biases compared to ERA5, which itself exhibits realistic spatial patterns of tracks and their monthly distribution. Models do at least agree on positive biases in track frequency east of Madagascar and somewhat in the Mozambique Channel. However, the models and ERA5 only produce Category 3 tropical cyclones at best. Wind speeds for 25 km resolution models have much larger positive biases than for 50 km ones, suggesting the former can simulate even higher‐category tropical cyclones. Considerable intermodel variation is also found in track changes between the future and historical periods. No systematic intercategory pattern of change exists, and low signal‐to‐noise may obscure any such patterns in the limited timespan of available data. Thus, no meaningful conclusions can be drawn regarding changes in track intensity. Nevertheless, track frequency broadly decreases across models for the region, as does accumulated cyclone energy. An east‐to‐west shift in track location from east of Madagascar toward the Mozambique Channel is also implied by track frequency and wind speed changes. Our findings provide information to potentially improve storm resiliency in this vulnerable region. [ABSTRACT FROM AUTHOR]

Wildfires have the potential to result in significant loss of life and property damage. Mountain wave flow events (Berg winds) are integrally linked to periods of enhanced fire danger. The basis for enhanced fire danger during periods of mountain winds has long been established, supported by evidence from a number of case studies. A fuzzy logic model, applied to hourly meteorological data from four different sites varying in elevation, allowed for an in-depth study of the effects of Berg winds on the microclimate and fire danger. Results indicate that night-time Berg wind events occur less frequently than daytime events, also having a significantly reduced influence on the microclimate. Daytime Berg wind events were shown to result in a significant change in the microclimate and fire danger across all sites. Night-time Berg wind events did not result in significant change to air temperature and relative humidity but when combined with significant changes to wind speed did result in significant increases in fire danger. The sensitivity of the Lowveld Fire Danger Index was also tested. The study emphasizes the need for boundary layer processes such as Berg winds to be taken into account when forecasting and monitoring fire danger. [ABSTRACT FROM AUTHOR]

Premise Methods Results Conclusions A key goal of evolutionary biologists is to understand how and why genetic variation is partitioned within species. In the yellow monkeyflower, Mimulus guttatus (syn. Erythranthe guttata), coastal perennial populations constitute a single genetically and morphologically differentiated ecotype compared to inland M. guttatus populations. While the coastal ecotype's distinctiveness has now been well documented, there is also environmental variation across the ecotype's range that could drive more continuous differentiation among its component populations.Based on previous observations of a potential cline within this ecotype, we quantified plant height, among other traits, across coastal perennial accessions from 74 populations in a greenhouse common garden experiment. To evaluate potential drivers of the relationship between trait variation and latitude, we regressed height against multiple climatic factors, including temperature, precipitation, and coastal wind speeds. We also accounted for exposure to the open ocean in all analyses.Multiple traits were correlated with latitude of origin, but none more than plant height. Height was negatively correlated with latitude, and plants directly exposed to the open ocean were shorter than those protected from coastal winds. Further analyses revealed that height was correlated with climatic factors (precipitation, temperature, and wind speeds) that were autocorrelated with latitude. We hypothesize that one or more of these climatic factors drove the evolution of latitudinal clinal variation within the coastal ecotype.Overall, our study illustrates the complexity of how the distribution of environmental variation can simultaneously drive the evolution of both distinct ecotypes and continuous clines within those ecotypes. [ABSTRACT FROM AUTHOR]

Reverse epidemiology is a mathematical modelling tool used to ascertain information about the source of a pathogen, given the spatial and temporal distribution of cases, hospitalisations and deaths. In the context of a deliberately released pathogen, such as Bacillus anthracis (the disease-causing organism of anthrax), this can allow responders to quickly identify the location and timing of the release, as well as other factors such as the strength of the release, and the realized wind speed and direction at release. These estimates can then be used to parameterise a predictive mechanistic model, allowing for estimation of the potential scale of the release, and to optimise the distribution of prophylaxis. In this paper we present two novel approaches to reverse epidemiology, and demonstrate their utility in responding to a simulated deliberate release of B. anthracis in ten locations in the UK and compare these to the standard grid-search approach. The two methods—a modified MCMC and a Recurrent Convolutional Neural Network—are able to identify the source location and timing of the release with significantly better accuracy compared to the grid-search approach. Further, the neural network method is able to do inference on new data significantly quicker than either the grid-search or novel MCMC methods, allowing for rapid deployment in time-sensitive outbreaks. Author summary: In this paper we demonstrate three methods for estimating the source location and timing of a deliberate release of Bacillus anthracis based on the temporal and spatial distribution of cases. Two of our proposed methods, a modified MCMC approach and a neural network based approach, provide significant improvements over previous methods by directly addressing the problematic parameter-likelihood surface, and, in the case of the neural network approach, addressing the slow deployment speeds of existing methods. Our results represent a major step forward in the accuracy and speed of epidemiological back-calculation. [ABSTRACT FROM AUTHOR]

We study the possible effect of climate change on the extreme wind over northern Europe using data from 18 models of the Sixth Phase of the Coupled Model Intercomparison Project (CMIP6) and the high-emission Shared Socioeconomic Pathway 5-8.5 (SSP585) scenario. We use the spectral correction method to correct the 6-hourly wind speeds and calculate the 50-year wind at an equivalent temporal resolution of 10 min, consistent with the International Electrotechnical Commission (IEC) standard. We obtain the possible effect of climate change through the comparison of the extreme wind parameters, including the 50-year wind and the 95%-percentile of the wind speed, and the change in turbine class at 50 m, 100 m and 200 m, between a near future period (2020-2049) and the historic period (1980-2009). The analysis shows an overall increase in the extreme winds in the North Sea and the southern Baltic Sea, but a decrease over the Scandinavian Peninsula and most of the Baltic Sea. However, the suggested change is not significant enough to conclude whether higher or lower classes of turbines will be needed in this area in the future. [ABSTRACT FROM AUTHOR]

Major power outages have risen over the last two decades, largely due to more extreme weather conditions. However, there is a lack of knowledge on the distribution of power outages and its relationship to social vulnerability and co-occurring hazards. We examined the associations between localized outages and social vulnerability factors (demographic characteristics), controlling for environmental factors (weather), in Washington State between 2018–2021. We additionally analyzed the validity of PowerOutage.us data compared to federal datasets. The population included 27 counties served by 14 electric utilities. We developed a continuous measure of daily outage burden using PowerOutage.us data and operationalized social vulnerability using four factors: poverty level, unemployment, disability, and limited English proficiency. We applied zero-altered lognormal generalized additive mixed-effects models to characterize the relationship between social vulnerability and daily power outage burden, controlling for daily minimum temperature, maximum wind speed, and precipitation, from 2018 to 2021 in Washington State. We found that social vulnerability factors have non-linear relationships with outages. Wind and precipitation are consistent drivers of outage occurrence and duration. There are seasonal effects that vary by county-utility area. Both PowerOutage.us and federal datasets have missing and inaccurate outage data. This is the first study evaluating differential exposure to localized outages as related to social vulnerability that has accounted for weather and temporal correlation. There is a lack of transparency into power outage distribution for those most vulnerable to climate impacts, despite known contributions by electric utilities to climate change. For effective public health surveillance of power outages and transparency, outage data should be made available at finer spatial resolution and temporal scales and/or utilities should be required to report differential exposure to power outages for socially vulnerable populations. [ABSTRACT FROM AUTHOR]

Omnidirectionality and simple design make VAWTs more attractive compared to HAWTs in highly turbulent and harsh operational environments including low wind speed conditions where this technology shines more. However, the performance of VAWTs is lacking compared to HAWTs due to low turbine efficiency at downstream caused by large wake vortices generated by advancing blades in the upstream position. Introducing variable design methods on VAWT provides better adaptability to the various oncoming wind conditions. This paper presents state-of-the-art variable methods for performance enhancement of VAWTs to provide better direction for the wind industry. The variable VAWT design can increase the lift and torque, especially at the downstream regions by managing the blade-to-wake interaction and blade angle of attack (AoA) well, hence contributing to the performance enhancement of VAWTs. In addition, the self-starting capabilities have also been found to improve by employing variable methods with a better angle of attack on the turbine blades. Nevertheless, the complexity of varying mechanisms and structural rigidity are the main challenges in adopting this idea. Yet, it possesses great potential to develop higher-efficiency VAWT systems that can operate in a wide range of wind speeds. [ABSTRACT FROM AUTHOR]

How might irrelevant events infiltrate voting decisions? The current research introduces a new mechanism—regulatory focus—by which incidental environmental factors can affect vote choice. Regulatory focus theory proposes that there are two fundamental psychological orientations in how people navigate their worlds: A prevention focus tunes cognition towards security, safety, protection, and risk aversion, whereas a promotion focus orients attention toward achieving growth and positive outcomes. We present a model for how wind speed on Election Day affects voting by shifting the regulatory focus of voters. We propose that increased wind speed shifts voters toward selecting prevention-focused options (e.g., restricting immigration, rejecting Brexit, rejecting Scottish Independence) over promotion-focused options (e.g., promoting immigration, favoring Brexit, favoring Scottish Independence). We further argue that wind speed only affects voting when an election clearly offers a choice between prevention and promotion-focused options. Using a mixed-method approach—archival analyses of the "Brexit" vote, the Scotland independence referendum, and 10 years of Swiss referendums, as well as one field study and one experiment—we find that individuals exposed to higher wind speeds become more prevention-focused and more likely to support prevention-focused electoral options. The findings highlight the political importance of incidental environmental factors. Practically, they speak to the benefit of absentee voting and expanding voting periods beyond traditional election days. [ABSTRACT FROM AUTHOR]

Wind energy is essential for sustainable energy development, providing a clean and reliable energy source through the wind turbine. However, the vortices and turbulence generated as wind passes through turbines reduce wind speed and increase turbulence, leading to significant power losses for downstream turbines in wind farms. This study investigates wake characteristics in wind turbines by examining the effects of different scale ratios on wake dynamics, using both experimental and numerical approaches, utilizing scaled-down models of the Aeolos H-20 kW turbine at scales of 1:33, 1:50, and 1:67. The experimental component involved wind tunnel tests in an open-circuit tunnel with adjustable wind speeds and controlled turbulence intensity. Additionally, Computational Fluid Dynamics (CFD) simulations were conducted using STAR-CCM+ (Version 15.06.02) to numerically analyze the wake characteristics. Prior to the simulation, a convergence test was performed by varying grid density and y+ values to establish optimized simulation settings essential for accurately capturing wake dynamics. The results were validated against experimental data, reinforcing the reliability of the simulations. Despite minor inconsistencies in areas affected by tower and nacelle interference, the overall results strongly support the methodology's effectiveness. The discrepancies between the experimental results and CFD simulations underscore the limitations of the rigid body assumption, which does not fully account for the deformation observed in the experiment. [ABSTRACT FROM AUTHOR]

This study investigates the influence of atmospheric stability and ground effects on wind turbine wake recovery, challenging the conventional linear relationship between turbulence intensity and wake expansion coefficient. Through comprehensive field measurements and numerical simulations, we demonstrate that the linear wake expansion assumption is invalid at far-wake locations under high turbulence conditions, primarily due to ground effects. We propose a novel nonlinear wake expansion model that incorporates both atmospheric stability and ground effects by introducing a logarithmic relationship between the wake expansion coefficient and turbulence intensity. Validation results reveal the superior prediction accuracy of the proposed model compared to typical engineering wake models, with root mean square errors of wake wind speed predictions ranging from 0.04 to 0.063. The proposed model offers significant potential for optimizing wind farm layouts and enhancing overall wind energy production efficiency. [ABSTRACT FROM AUTHOR]

Passively tuned mass dampers (TMDs) are known to effectively mitigate the vibration of wind turbines. However, existing literature predominantly examines their application in damping vibrations of the tower or platform, overlooking the potential benefits of installing TMDs on the turbine blades themselves. This study investigates the impact of wind and wave loads on TMD damping effectiveness and proposes a comprehensive damping strategy involving TMDs installed in both the nacelle and the blades. The design optimized the mass and stiffness of these TMDs to enhance their performance. Results indicate that, as wind speeds increased from 12 m/s to 24 m/s, the power spectral density at the tower's natural frequency (0.22 Hz) more than doubled. Notably, TMDs exhibited robust vibration damping capabilities under high wind speeds. Specifically, at wind speeds of 24 m/s, TMDs reduced anterior–posterior and lateral displacement at the tower top by 61.2% and 166.8%, respectively, when two TMDs were combined. Conversely, the study found that TMDs did not significantly improve vibration damping at lower to moderate wind speeds. This research underscores the importance of optimizing TMDs for high wind conditions to ensure wind turbine stability and mitigate potential vibration-related risks effectively under varying environmental loads, including wind and waves. It offers valuable insights for the refined design and deployment of TMDs in wind energy applications. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach to determining the ampacity of DC and AC railway overhead contact lines, considering both operational and design factors. The ampacity of contact lines is influenced by several design parameters, including materials, cross section and the number of catenary and contact wires, etc. Additionally, the permissible long-term and short-term current values, which correspond to the permissible temperatures defined by EN 50119:2020, are affected by operational factors such as ambient temperature, solar radiation, heat exchange conditions, wind speed, wear of contact wires. Existing methods for determining the ampacity of overhead contact lines often fail to account adequately for these critical factors and lack the necessary procedures to calculate the 30 min ampacity required by EN 50119:2020. In response, the method proposed in this study adapts the procedures of IEEE 738-2012 to the specific needs of railway contact lines, taking into account the effect of contact wire wear on current distribution and overall ampacity. The proposed method offers a more realistic and practical approach to determining the ampacity of contact lines, thereby enhancing the reliability and efficiency of the traction power supply infrastructure. This method could be useful for railway infrastructure managers to ensure the safe and efficient operation under varying environmental and operational conditions. [ABSTRACT FROM AUTHOR]

This research study aims to develop a system which ensures the mobility of a floating dock and its stability in position during docking operations. The dock is designed for operation in a river canal. In order to dock a ship, it is moved away from the quay over a dock trench. Initial requirements and design criteria for the system were determined. The most important of them include docking in the maximum weather conditions, corresponding to a wind speed of 5° Beaufort (5°B), and a zero-emission target for the power supply system (use of a renewable energy source). A wire and winch system was designed to move the dock and stabilise it in position during docking operations. The system comprises mooring wires which are tied to bollards on both quays, and wire winches mounted on both sides of the dock. The wire winches are hydraulically driven, and the hydraulic pumps, run by electric motors, are powered with batteries charged using photovoltaic panels. Statistical environmental parameters (wind, river current) were analysed and the probability of certain mooring wire loads and the corresponding wire winch power output were quantified. Based on these calculations, the power of photovoltaic panels and capacity of the batteries required to power the dock moving system were determined. This paper discusses the system design as well as the results of trials. [ABSTRACT FROM AUTHOR]

Water scarcity is a serious threat to the survival and development of mankind. Interfacial solar steam generation (ISSG) can alleviate the global freshwater shortage by converting sustainable solar power into thermal energy for desalination. ISSG possesses many advantages such as high photothermal efficiency, robust durability, and environmental friendliness. However, conventional evaporators suffered from huge heat losses in the evaporation process due to the lack of efficient thermal management. Herein, hydrophilic Tencel yarn is applied to fabricate a three-dimensional double-layer fabric evaporator (DLE) with efficient multi-stage thermal management. DLE enables multiple solar absorptions, promotes cold evaporation, and optimizes thermal management. The airflow was utilized after structure engineering for enhanced energy evaporation efficiency. The evaporation rate can reach 2.86 kg·m−2·h−1 under 1 sun (1 kW·m−2), and 6.26 kg·m−2·h−1 at a wind speed of 3 m·s−1. After a long duration of outdoor operation, the average daily evaporation rate remains stable at over 8.9 kg·m−2, and the removal rate of metal ions in seawater reaches 99%. Overall, DLE with efficient and durable three-dimensional multi-stage thermal management exhibits excellent practicality for solar desalination. [ABSTRACT FROM AUTHOR]

In recent years, wind power generation has been promoted as a countermeasure to global environmental problems. However, the introduction of many wind power generators into the power system may cause system frequency fluctuations. This paper proposes a control method to reduce system frequency fluctuations by using the rotor kinetic energy (RKE) of a variable speed wind turbine (VSWT). When the frequency falls, this method suppresses fluctuations by consuming RKE to increase VSWT power generation, and when it rises, it decreases VSWT power generation by accumulating RKE. The effectiveness of this method is confirmed through simulations using PSCAD/EMTDC. [ABSTRACT FROM AUTHOR]

The instability of the increasingly important photovoltaic (PV) electricity generation in Korea due to a dependence on meteorological conditions is an emerging problem. In this study, we examined the influence of various meteorological conditions on the prediction accuracy of PV generation and module temperature. The predictions were based on weather data acquired from the Korea Meteorological Administration and compared with actual PV generation data from the Dangjin coal yard PV power facility. The results were analyzed on the basis of meteorological conditions, insolation, ambient temperature, and wind velocity. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TC) are common high-impact weather events in the southeastern United States. One of the most intense TCs to hit north-central Florida in recent decades was Hurricane Frances (2004), which resulted in over $10B in damages. Given the growing concern about the relationship between anthropogenic climate change, precipitation, and TCs, we investigated how a Hurricane Frances-like event would affect north-central Florida in the late 21st century under an RCP-8.5 scenario. Using a 'pseudo' global warming dataset based on the high-resolution Weather Research and Forecasting (WRF) model, we explore historical and future simulations of Hurricane Frances's path, precipitation rates, and wind speeds. We discover that, across north-central Florida sub-daily to daily rainfall totals in the future simulation exceed that of the historical, having return period events in some cases reaching 500-year thresholds. We also find more broadly across the spatial domain of the hurricane that rainfall rates in all temporal categories and total rainfall accumulation increased significantly. Results for wind speeds were mixed, with an evident expansion of tropical storm winds, but a slight contraction of the spatial extent of strongest winds at the surface. We discuss the implications of these findings for decision-makers in Florida. [ABSTRACT FROM AUTHOR]

Sea spray particles play a key role in transferring momentum, heat, and gas across the atmosphere–ocean interface at high wind speeds and represent an important source of cloud condensation nuclei which affect the genesis, chemistry, and radiative properties of marine clouds. Here, we present direct measurements of sea spray particle fluxes obtained using an eddy covariance technique through the use of a newly developed high temporal resolution optical particle counter. With this instrumentation measurements were made over the coastal ocean during a 5-week field campaign conducted at an observation pier from November to December 2021. Our optical particle counter was capable of measuring size spectra at a rate of 10 Hz in 8 channels covering a range of mean radii between 0.3 and 15. The power spectra of particle number density followed the Kolmogorov −2/3 power law. The shape of the cospectrum of the particle number density flux was basically similar to that of the cospectra of the heat and gas fluxes. The measured sea spray particle fluxes at mean wind speeds of up to 21 m s−1 were dominated by an upward flux, which likely represents aerosol production caused by the bursting of bubbles at the ocean surface. [ABSTRACT FROM AUTHOR]

Near-surface ocean wind measurements are important for weather forecasting, determining surface transports, and estimating air-sea interactions; however, in-situ wind observations are often limited. Previous studies indicate that the equilibrium range of the surface gravity wave spectrum can be used to estimate surface wind velocity. This approach is tested using spectral wave measurements from the Coastal Data Information Program (CDIP) buoy array off Monterey, California. Quality controlled wind vectors inferred from wave spectra are statistically compared to measurements from a nearby National Data Buoy Center (NDBC) buoy, demonstrating strong agreement with the control observations with root mean square errors for speed and direction of 1.8 m/s for all wind speeds and 13.2° for wind speeds greater than 7 m/s. We expand this estimation method to account for biofouling, which causes high-frequency damping of the wave spectrum, and the effects of form factor, which impact the platform's dynamic response to high-frequency waves. The method produces wind-proxy measurements solely from wave spectra and wave-based drag parametrizations, making it useful for operational integration. This work demonstrates the ability to make robust wind velocity estimates using wave data from multiple sources, increasing the coverage of wind information over the coastal and open ocean. [ABSTRACT FROM AUTHOR]

The generation of ocean surface waves by wind has been studied for a century, giving rise to wave forecasting and other crucial applications. However, the reacting force of swell waves on the turbulence in the marine atmospheric boundary layer (ABL) remains unknown partly due to the unclear magnitude and profile of wave-coherent (WC) stress. In this study, the intersection frequency between the energy-containing range and inertial subrange range in the turbulent spectra is identified based on the attached eddy model (AEM), as the intersection modulated by swell wave could help to comprehend the physical process between the ocean surface wave and the marine ABL. Using observations from a fixed platform located in the South China Sea, this study shows that the intersection when the WC stress accounts for a lower proportion of the total wind stress (<10%) follows U/(2πz) given by AEM, where U is the wind speed and z is the height. While the intersection depends on the drag coefficient of WC stress for the case, WC stress accounts for a large part of the total wind stress (>10%). Considering the unclear magnitude and profile of WC stress, this study derives a new function to depict the WC stress. Significance Statement: Turbulence located in the energy-containing range of the spectra is the primary source of momentum, heat, and water vapor fluxes between the ocean and marine atmospheric boundary layer (ABL). Thus, a better understanding of the turbulent structure within the wave boundary layer can help us accurately parameterize those fluxes. In addition to absorbing energy from the marine ABL, waves, especially swell waves, influence the turbulent structure. However, until now, the turbulent structure is unclear due to the unclear wave-coherent stress size and profile. In this study, a function that can depict the wave-coherent stress is proposed. We found that the wave-coherent stress can modulate the intersection between the energy-containing range and the inertial subrange range in the turbulent spectra. [ABSTRACT FROM AUTHOR]

The state of Hawaii is a series of mountainous islands with a topography that is much more complex than the simple isolated hills and escarpments included in ASCE standard ASCE/SEI 7-22 (Minimum design loads and associated criteria for buildings and other structures, ASCE 7). Hawaii state and county building codes have incorporated topographic wind speed mapping since 2007. In 2010, ASCE 7-10 recognized Hawaii as a special wind region. The design wind speed maps, Kzt maps, and site-specific directionality factors as adopted in Hawaii's state building codes constituted the "special Kzt topographic effect adjustments" of the authority having jurisdiction that were referenced in ASCE 7-10. In ASCE 7-16 and ASCE 7-22, microzoned wind speed maps for Hawaii, including the effect of topography and directionality, were incorporated for strength design return periods. This paper provides information on the development of an improved generation of higher-resolution basic design wind speed maps for the state of Hawaii, including better accuracy of topographic and directionality effects. The digital format of these wind speed maps can be readily incorporated into the ASCE 7 digital hazard tool interfaces. [ABSTRACT FROM AUTHOR]

Tropical cyclone (TC) winds control design wind speeds for much of the eastern United States. Those winds are likely to intensify with climate change, but climate change was not considered in the ASCE 7-22 design wind speed maps, potentially causing many structures to be designed with unacceptably high levels of risk. In this study, we investigate (1) the increases in design wind speed due to climate change; and (2) the resulting risk to structures if climate change is not considered. We estimated the design wind speeds for US counties affected by TCs along the Gulf and Atlantic coasts using nonstationary methods based on a set of synthetic TCs (1,000–1,500 year simulations) downscaled from the latest global climate projections (CMIP6) for the high-emissions scenario (SSP5-8.5). It was found that over the 21st century, 50-year return period winds would increase by an average of around 10% along the US Gulf and Atlantic coasts. Depending on the risk category, design lifetime, and year of construction, design wind speeds (targeting lifetime exceedance probability) are projected to increase by an average of 3%–6% for all counties studied and 6%–15% for coastal counties. For Risk Category II–IV structures, depending on the design lifetime and year of construction, 8%–36% of all counties studied and 25%–66% of coastal counties would experience projected lifetime exceedance probabilities that were at least two risk categories too low; for example, in up to 26% of all counties studied and 54% of coastal counties, a Risk Category III structure would be effectively designed as Risk Category I or lower. [ABSTRACT FROM AUTHOR]

Recruitment is a critical process in the dynamics of fish populations since it represents the abundance of new fish that enter a population each year. In Ekman‐type upwelling ecosystems, wind is a critical factor for small pelagic fish recruitment, as it controls food availability and physical constraints such as turbulence and offshore advection. In this study, we evaluate the effect of wind, chlorophyll‐a, and spawning biomass as independent variables on anchovy recruitment. Using generalized additive models (GAMs), we tested (i) the significance of each factor, (ii) the shape of the relationship between recruitment and predictors variables, (iii) recruitment regimes in the series, and (iv) whether extended windy events are associated with low recruitment levels potentially related to offshore transport of early life stages. The study period spanned from 1990 to 2021, focusing on the austral spring in south‐central Chile (35–40°S) when both upwelling and anchovy spawning are maximized. GAMs revealed a parabolic relationship between the velocity of upwelling‐favorable winds and anchovy recruitment. Maximized recruitment occurred at wind speeds around 6 m s−1 but decreased with winds above 7 m s−1 and below 5 m s−1, and during periods of extended windy events (i.e., those lasting more than 15 days). Chlorophyll‐a showed no significance on anchovy recruitment, suggesting that phytoplankton were not a limiting factor for anchovy early survival. We also found that anchovy recruitment regimes were associated with specific wind intensities. We discussed the pertinence of incorporating a recruitment index based on wind in the fishery management of the anchovy in south‐central Chile. [ABSTRACT FROM AUTHOR]

Tropical cyclone intensification is simulated with a cloud-resolving model under idealized conditions of constant SST and unidirectional environmental vertical wind shear maximized in the middle troposphere. The intensification process commonly involves a sharp transition to relatively fast spinup before the surface vortex achieves hurricane-force winds in the azimuthal mean. The vast majority of transitions fall into one of two categories labeled S and A. Type S transitions initiate quasi-symmetric modes of fast spinup. They occur in tropical cyclones after a major reduction of tilt and substantial azimuthal spreading of inner-core convection. The lead-up also entails gradual contractions of the radii of maximum wind speed rm and maximum precipitation. Type A transitions begin before an asymmetric tropical cyclone becomes vertically aligned. Instead of enabling the transition, alignment is an essential part of the initially asymmetric mode of fast spinup that follows. On average, type S transitions occur well after and type A transitions occur once the cyclonically rotating tilt vector becomes perpendicular to the shear vector. Prominent temporal peaks of lower-tropospheric CAPE and low-to-midlevel relative humidity averaged over the entire inner core of the low-level vortex characteristically coincide with type S but not with type A transitions. Prominent temporal peaks of precipitation and midlevel vertical mass flux in the meso-β-scale vicinity of the convergence center characteristically coincide with type A but not with type S transitions. Despite such differences, in both cases, the transitions tend not to begin before the distance between the low-level convergence and vortex centers divided by rm reduces to unity. [ABSTRACT FROM AUTHOR]

The issue of pedestrian-level wind environments around high-rise buildings is closely related to the comfort and safety of human settlements. In this paper, we study the effects of different wind direction angles and spacing ratios on the wind environment at pedestrian heights around buildings arranged in an equilateral triangle configuration. Three-dimensional steady-state numerical simulation was employed, with the standard k-ε model selected as the turbulence model. Wind speed ratios and different area ratio parameters are used to quantitatively express the degree and range of influence of wind speed by buildings. The results show that the maximum wind speed ratio at the corner of a building is greatly affected by the wind direction angle, with 45°, 135°, and 157.5° being the unfavorable wind direction angles. Conversely, the area ratio of different areas is greatly affected by the spacing ratio. As the spacing ratio increases, the mutual interference effect between buildings weakens, resulting in a better pedestrian wind environment. Owing to the unique layout of the building group, different degrees of ventilation corridors are formed among the three buildings. The wind speed amplification effect in the corridors is more significant, and the areas with poor wind environments are concentrated in these corridors. [ABSTRACT FROM AUTHOR]

The impact of tropical cyclones on the operation of bridges and railways are mostly dependent on the forecast wind speed trend (upward, downward or staying steady) at present in Hong Kong. There are requests to forecast the exceedance of wind speed thresholds for such operations with a lead time of many hours ahead. This study considers the technical feasibility of forecasting the wind speed along a recently built bridge in Hong Kong with a coupled mesoscale numerical weather prediction (NWP)–computational fluid dynamics (CFD) model. This bridge features numerous anemometers where the coupled model can be verified. It is found that these two tropical cyclone cases are very challenging, especially in representing the wind structure of the cyclone because of its relatively small circulation. As such, the timing of the maximum wind could be 2 to 4 h earlier than the actual observation. The maximum wind speed from CFD modeling could be higher than that from the NWP model alone by 5 to 10 m/s, which shows that CFD modeling could add value in the forecasting of wind speed exceedance, although the maximum simulated value is still lower than the actual observation by as much as 10 m/s. As a result, while the general wind speed trend may be forecast, the exceedance of definite values of wind speed limits is still practically rather challenging, given the present two cases of tropical cyclones. [ABSTRACT FROM AUTHOR]

Existing research into this topic primarily focuses on low-altitude areas, neglecting the impact of extreme environmental conditions such as low temperature, low oxygen level, and low pressure in high-altitude regions. Based on the smoke diffusion theory, a series of CFD numerical simulations were conducted in order to investigate the characteristics of smoke diffusion in the highway tunnel at high altitude. The results indicated that the increase in altitude would enhance the longitudinal propagation velocity of smoke, leading to a more pronounced impact on temperature, CO concentration, and visibility at characteristic heights. Meanwhile, the altitude intensifies the inhibitory impact of longitudinal ventilation on smoke diffusion upwind of the fire source and augments the acceleration effect on smoke diffusion downwind, thereby impeding personnel evacuation on the downwind side. By taking the hazardous range at a characteristic height under the impact of wind velocity and the deceleration of evacuation velocity due to altitude into consideration, a new recommended reduction factor was deduced to design adits for people passing spacing in highway tunnels at high altitude. The findings can serve as a valuable reference for the personal evacuation in high-altitude highway tunnel fires and the design of spacing between adits for people passing within such tunnels. [ABSTRACT FROM AUTHOR]

The synchronization and intensity of fluctuating wind speeds and wave surfaces in wind–wave joint propagation processes are affected by the coherence of the marine ambient factors of fluctuating wind and random waves. This coherence further affects the precise calculations of wind–wave joint actions on marine structures. Therefore, a wind–wave joint propagation numerical flume was established based on the numerical simulation of random waves and fluctuating wind fields. A series of numerical simulations of wind–wave joint propagations were carried out. Based on the numerical results, the influences and influence laws of factors such as wind speed position height, significant wave height and wave spectrum peak frequency on the wind–wave coherence values were studied. According to the influence characteristics of these factors, a function of wind–wave coherence values for random wind–wave joint propagation was calculated. The coherence function takes frequency as the variable, while parameters include significant wave height, wind speed position height and wave spectrum peak frequency. Through a series of numerical simulation results, data fitting was used to calculate the parameter coefficients of the coherence function. The established random wind–wave coherence function can be described using the wind–wave joint fields of marine structures and the computational analyses of structural wind–wave joint actions. [ABSTRACT FROM AUTHOR]

The seasonal variation in wind resources has a great impact on wind energy generation, affecting the maintenance planning, operational strategies, and economic benefits of wind farms. Therefore, effective seasonal prediction of wind resources is crucial for the wind power industry. This study evaluates the seasonal prediction skill for global onshore wind resources using the SIDRI-ESS V1.0 dynamic prediction system. High prediction skill for 10 m wind speed (ws10m) is observed mainly in six regions: southern North America, northern South America, western and eastern Europe, and South and East Asia. These regions already have a substantial wind power industry or possess rich wind resources and will need wind power industry deployment in the future. Prediction skill is the highest at a 1-month lead time for most regions and decays as the lead time increases. The highest skill emerges in East Asia, with a temporal correlation coefficient (TCC) reaching 0.7, and persists with a 1-month to 5-month lead time. However, the highest skill for southern North America is at a 6-month lead time. Additionally, ensemble prediction effectively reduces uncertainty, such that a multi-member ensemble mean always matches or even exceeds the individual ensemble member with the best performance. Ensemble size analysis shows that increasing the number of ensemble members generally enhances the prediction skill, with 24 members being sufficient for most regions and lead times. However, further increasing the ensemble size is essential to improve the prediction skill at a 6-month lead time. Meanwhile, we also indicate that ws10m can be used as a proxy in evaluating seasonal prediction of wind resources over most regions, while direct seasonal prediction of wind power density is more effective for northern South America. The high seasonal prediction skill of SIDRI-ESS V1.0 highlights its potential for providing valuable seasonal climate prediction services to the wind power industry. [ABSTRACT FROM AUTHOR]

Wind speed and direction variations across the rotor affect power production. As utility‐scale turbines extend higher into the atmospheric boundary layer (ABL) with larger rotor diameters and hub heights, they increasingly encounter more complex wind speed and direction variations. We assess three models for power production that account for wind speed and direction shear. Two are based on actuator disc representations, and the third is a blade element representation. We also evaluate the predictions from a standard power curve model that has no knowledge of wind shear. The predictions from each model, driven by wind profile measurements from a profiling LiDAR, are compared to concurrent power measurements from an adjacent utility‐scale wind turbine. In the field measurements of the utility‐scale turbine, discrete combinations of speed and direction shear induce changes in power production of −19% to +34% relative to the turbine power curve for a given hub height wind speed. Positive speed shear generally corresponds to over‐performance and increasing magnitudes of direction shear to greater under‐performance, relative to the power curve. Overall, the blade element model produces both higher correlation and lower error relative to the other models, but its quantitative accuracy depends on induction and controller sub‐models. To further assess the influence of complex, non‐monotonic wind profiles, we also drive the models with best‐fit power law wind speed profiles and linear wind direction profiles. These idealized inputs produce qualitative and quantitative differences in power predictions from each model, demonstrating that time‐varying, non‐monotonic wind shear affects wind power production. [ABSTRACT FROM AUTHOR]

A standalone Advanced Circulation (ADCIRC) model for the east coast of India with a high-resolution grid of 100 m near the coast is used to evaluate coastal inundation resulting from the storm tides generated by recent cyclones. A directional surface roughness parametrization that alters wind speed and Manning's n friction coefficient to compute bottom friction based on land use/land cover (LULC) at a particular location is incorporated in the model. ERA5 reanalysis winds highlight that the cyclonic winds over the land are less intensive than nearby coastal oceans, particularly during landfall time, by approximately 29%–50%. Experiments are also designed to quantify the impact of surface and bottom friction on wind speed and the inward propagation of storm tides. A comparison of cyclonic wind speed after incorporating LULC data in the model is made with an automatic surface observation system (ASOS). It suggests a 15%–29% reduction, consistent with ASOS. The inundated area computed for the cyclones advocates a significant reduction (15%–50%) due to LULC. Sensitivity experiments with LULC are performed to examine the impact of mangroves in the Krishna estuary located in between two concave-shaped coastal geometries. Replacing wetlands with Mangroves results in a simultaneous decline in wind speed (12.5%) and inundated area (13.4%). It also highlights that bottom friction contributes (9.4%) in the inundated area against surface friction (4%). This study infers that further investigation and planning are mandatory to ensure coastal mangrove restoration initiatives and effective coastal management practices. [ABSTRACT FROM AUTHOR]

With the increase in span, the flexibility and sensitivity to aerodynamic damage of bridges significantly increase. However, current research studies primarily focus on analyzing the single environment, leaving the safety and durability of bridges under extreme weather relatively understudied, such as snowdrift. This study selects four typical box girder bridges as test models to conduct wind tunnel tests. By analyzing similarity principles and particle properties, polyethylene particles are chosen as the test medium, and their simulation accuracy is validated using a step-type flat roof model. The study then explores wind-induced snow redistribution on the surfaces of the four box girder bridges under different horizontal wind speeds, initial particle heights, and wind attack angles. The results demonstrate that as the surface configurations of the test models become more complex, the particle redistribution becomes more chaotic. Among the three test conditions, the wind attack angle exerts the greatest influence, followed by horizontal wind speed and initial particle height. Notably, the dimensionless redistribution coefficients of particles on the surface of the large-span highway box girder bridge show the largest differences under these test conditions, with average differences and maximum differences reaching 50.3% and 63.5%, respectively, for different wind attack angles. These findings provide data support for the investigation of the safety and durability of real bridges under extreme weather conditions. [ABSTRACT FROM AUTHOR]