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Meteorological disasters pose a serious threat to the State Grid Corporation of China, which covers ~ 88% of Chinese national territory. Of these, strong winds deserve a special attention, as they often induce windage yaw discharge of transmission lines and even toppling of transmission towers, resulting in serious economic losses. On 28 June 2023, a severe tripping incident of transmission line appears in Eastern Inner Mongolia due to strong winds. In this study, we conduct comprehensive analyses to clarify the favorable background conditions and governing mechanisms for producing the strong winds. Main results are shown as follows. Synoptic analysis indicates that, the favorable background environments for the event are characterized by a strong upper-level jet associated upper tropospheric divergence; an intense middle-level warm advection ahead of a shortwave trough; and a long-lived lower-tropospheric mesoscale vortex. The strong winds that cause the tripping incident mainly occur in the southeastern quadrant of the vortex. Vorticity budget presents that the period from the mesoscale-vortex's formation to 4 h before is crucial to the mesoscale vortex, as cyclonic vorticity increases rapidly mainly due to the lower-level convergence-related vertical stretching. In contrast, the horizontal transport mainly results in a net export of cyclonic vorticity, which is the most detrimental factor. Kinetic energy (KE) budget shows that, after the mesoscale vortex forms, the strong winds within its southeastern quadrant enhance rapidly. Overall, the positive work done by the pressure gradient force associated with the mesoscale vortex dominates the enhancement of strong winds; the horizontal transport of KE is the second dominant factor, and the vertical transport of KE (i.e., the downward momentum transportation) shows the least contribution. [ABSTRACT FROM AUTHOR]

Strong winds can lead to more complex ice shedding oscillation processes for overhead conductors, inducing flashovers, strand breakages and other accidents. This study analyzes the aerodynamic parameters of several typical icing features and establishes a numerical model for ice shedding on overhead conductors under strong wind conditions. The results show that for the same amount of icing, the resistance and lift force on the conductor changes with ice shape, wind attack angle and wind speed, which has a significant effect on the ice shedding jumping process. When the wind attack angle approaches 180°, the airflow resistance of the fan-shaped and D-shaped icing conductors significantly increases. And in the process of ice shedding response of transmission lines, the lateral amplitude may exceed 20 m, which increase the discharge risk of horizontally arranged conductors. Moreover, for the significant lateral oscillation of conductors by ice shedding under strong wind, the maximum horizontal displacement is approximately 1.6 times the difference in lateral position before and after ice shedding. [ABSTRACT FROM AUTHOR]

The benefits of urban trees are very well known, but they can fall and cause damage, putting people's lives at risk. There are few studies on the vulnerability of species to falling. In Lisbon (Portugal), fallen trees have been recorded since 1990 without, however, the identification of the species, knowledge of which is fundamental for improving their management. This study aimed to identify the tree species most vulnerable to falling in Lisbon through a proximity-based approach of known species, since the city has 47,713 inventoried trees, of which only 26,595 (55.7%) were identified. Four criteria were designed to presume the species: (i) the tree must be within 15 m from the street median axis; (ii) at least three individuals within 30 m from the occurrence must belong to the same species; (iii) the surrounding species must be representative in the street (>50%); and (iv) visual identification of avenue medians. Through this approach, considering 3767 fallen trees, it was possible to identify 736 cases, representing 19.5% of all occurrences throughout the studied time and representing 43 different species. Species like Morus nigra L., Tipuana tipu (Benth.) Kuntze, Liriodendron tulipifera L., Prunus cerasifera Ehrh., and Koelreuteria paniculata Laxm. were most vulnerable. Additionally, in 57.7% of cases (425 fallen trees), the wind speed 12-h before the occurrence was greater than 7 m s−1. This research will provide important data for urban planners seeking to maximize the ecosystem services of urban trees. [ABSTRACT FROM AUTHOR]

To master the characteristics of changes related to meteorological disasters in Cao Fei Dian's solar greenhouse grapes and effectively reduce the risk of meteorological disasters, data from the Cao Fei Dian National Meteorological Observation Station from 1978 to 2017 were used. The change trends and periodic characteristics of the frequency of low temperature, strong wind, and insufficient sunlight during the grape growing period in the solar greenhouse were statistically analyzed on an annual and monthly scale using the climate tendency rate and Morlet wavelet analysis methods. Forty-year analysis in solar greenhouses showed: 357 low temperature, 127 strong wind, and 227 insufficient sunlight events during grape cultivation. Decadal trends were -4.48, -2.59, and +1.15 events/decade for low temperatures, strong winds, and insufficient sunlight, respectively, with 4-9 and 12-15-year cycles. Monthly trends indicated a decrease in low temperatures (-0.95 to -2.26 events/decade) in January, February, and December, and strong winds (-0.12 to -0.76 events/decade) from November to May, with cycles of 3-19 years. Insufficient sunlight in January, June, November, and December increased by 0.26 to 0.40 events/decade, with 3-16-year cycles. [ABSTRACT FROM AUTHOR]

Clarifying the influence of disturbances by biotic and abiotic agents on long‐term changes in forest structure and demographic rates is an important task of forest ecology. Here, we investigated changes in forest structure and demographic rates and the effects of biotic and abiotic factors (sika deer, ambrosia beetle, neighborhood trees, and indices of strong wind and wetness) in a 4‐ha long‐term ecological study plot in a lowland warm temperate rain forest on Yakushima Island, Japan, from 1996 to 2019 for three regeneration groups related to gap dynamics (gap demander: GD, light shade tolerant: LS, and strong shade tolerant: SS). GD had relatively lower recruitment and survival than LS and/or SS. Changes in demographic rates were not significantly correlated with those in the index of strong wind in any regeneration group. The effects of sika deer on demographic rates did not differ among groups. Stems of Fagaceae species belonging to LS attacked by ambrosia beetles recorded in 2013 did not significantly differ in RGR and survival rates. Our results indicate that despite the relatively long monitoring period of 23 years, we did not detect significant effects of strong winds on demographic rates among regeneration groups, and shade‐tolerant species (LS and SS) showed better demographic performance than light‐demanding species (GD) and an increase in total basal area over time. We need longer monitoring of forest dynamics to understand forest responses to disturbances considering several factors, including the time lag of demographic responses to disturbances and the long‐term effects of disturbances. [ABSTRACT FROM AUTHOR]

Southern Brazil is a region strongly influenced by the occurrence of extratropical cyclones. Some of them go through a rapid and intense deepening and are known as explosive cyclones. These cyclones are associated with severe weather conditions such as heavy rainfall, strong winds, and lightning, leading to various natural disasters and causing socioeconomic losses. This study investigated the interaction between atmospheric and oceanic conditions that contributed to the rapid intensification of the cyclone that occurred near the coast of South Brazil from 29 June to 3 July 2020, causing significant havoc. Hourly atmospheric and oceanic data from the ERA5 reanalysis were employed in this analysis. The results showed that warm air and moisture transportation were key contributors to these phenomena. In addition, the interaction between the jet stream and the cyclone's movement played a crucial role in cyclone formation and intensification. Positive sea surface temperature anomalies also fueled the cyclone's intensification. These anomalies increased the surface heat fluxes, making the atmosphere more unstable and promoting a strong upward motion. Due to the strong winds and the heavy rainfall, the explosive cyclone caused substantial impacts on the power services, resulting in widespread power outages, damaged infrastructure, and interruptions in energy distribution. This work describes in detail the cyclone development and intensification and aims at the understanding of these storms, which is crucial for minimizing their aftermaths, especially on energy distribution. [ABSTRACT FROM AUTHOR]

Wind velocity is usually assumed to obey a stationary stochastic process in wind engineering, and this may cause significant bias in describing extremely severe strong wind such as typhoons and thunderstorms. To take into account the non-stationary characteristics of extreme wind, a novel evolutionary power spectral density (EPSD) model is proposed, and the spectral representation method (SRM) is introduced to simulate the whole process of strong winds. Firstly, the wavelet transform (WT) method is adopted to capture the three-dimensional time-varying properties of the low-frequency mean winds, and the associated turbulence features, including turbulent intensity, gust factor, probability density function, and power spectrum, are analyzed in depth. Secondly, the measured horizontal EPSD of strong winds are estimated. Thirdly, the performance of the proposed EPSD model is validated. Finally, the whole process of non-stationary strong winds are simulated and discussed. The results show that the proposed EPSD models are in good agreement with the measured EPSD, and the time-frequency features of the power spectrum of the simulated winds are well reproduced, which provides a powerful tool for large eddy simulation and wind engineering studies under non-stationary extreme wind climate.

The benefits of urban trees are very well known, but they can fall and cause damage, putting people’s lives at risk. There are few studies on the vulnerability of species to falling. In Lisbon (Portugal), fallen trees have been recorded since 1990 without, however, the identification of the species, knowledge of which is fundamental for improving their management. This study aimed to identify the tree species most vulnerable to falling in Lisbon through a proximity-based approach of known species, since the city has 47,713 inventoried trees, of which only 26,595 (55.7%) were identified. Four criteria were designed to presume the species: (i) the tree must be within 15 m from the street median axis; (ii) at least three individuals within 30 m from the occurrence must belong to the same species; (iii) the surrounding species must be representative in the street (>50%); and (iv) visual identification of avenue medians. Through this approach, considering 3767 fallen trees, it was possible to identify 736 cases, representing 19.5% of all occurrences throughout the studied time and representing 43 different species. Species like Morus nigra L., Tipuana tipu (Benth.) Kuntze, Liriodendron tulipifera L., Prunus cerasifera Ehrh., and Koelreuteria paniculata Laxm. were most vulnerable. Additionally, in 57.7% of cases (425 fallen trees), the wind speed 12-h before the occurrence was greater than 7 m s−1. This research will provide important data for urban planners seeking to maximize the ecosystem services of urban trees.

Strong winds can lead to more complex ice shedding oscillation processes for overhead conductors, inducing flashovers, strand breakages and other accidents. This study analyzes the aerodynamic parameters of several typical icing features and establishes a numerical model for ice shedding on overhead conductors under strong wind conditions. The results show that for the same amount of icing, the resistance and lift force on the conductor changes with ice shape, wind attack angle and wind speed, which has a significant effect on the ice shedding jumping process. When the wind attack angle approaches 180°, the airflow resistance of the fan-shaped and D-shaped icing conductors significantly increases. And in the process of ice shedding response of transmission lines, the lateral amplitude may exceed 20 m, which increase the discharge risk of horizontally arranged conductors. Moreover, for the significant lateral oscillation of conductors by ice shedding under strong wind, the maximum horizontal displacement is approximately 1.6 times the difference in lateral position before and after ice shedding.

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In recent years, a decrease in dissolved oxygen in the lake bottom has been observed in the northern part of Lake Biwa, the largest freshwater lake in Japan. The main physical controlling factor is considered to be changes in stratification, which are influenced by weather and climatic conditions. As atmospheric temperature increases, lake surface temperature rises, and stratification is formed. The strength of stratification has a significant impact on the transport of various material cycles, such as dissolved oxygen and nutrients, from the lake surface to the bottom layer. Therefore, in this study, the analysis of the effect of strong winds during the stratification collapse period (autumn) on the stratification structure of Lake Biwa was performed. Baseline simulations using actual meteorological data and experimental simulations using meteorological data with modified wind speed and direction were conducted. The numerical experiments showed that collapse of stratification was more likely to occur in autumn than in summer, and vertical mixing was enhanced. When strong winds blew more in one direction, vertical mixing was further enhanced when the duration of strong winds was longer during periods of weak stratification, as well as the results during the stratification period. When winds of the same magnitude as during the stratification period blew during periods of decreasing water temperature, a decrease in bottom water temperature was observed prior to the full-layer circulation in the following year. This suggested that strong winds during the decreasing temperature period had a strong influence on the water temperature environment next year. [ABSTRACT FROM AUTHOR]

The downburst events have been a research focus for decades, as their associated disastrously strong winds pose a great threat to aviation, the shipping industry, agriculture, and the power industry. On 14 May 2021, a series of severe convection occurred in middle and eastern China, during which six 500-kilovolt transmission line towers in Zhejiang were toppled down by a downburst event, resulting in a large range of power outages. By using the Weather Research and Forecasting (WRF) model version 4.4, key features of the downburst event were reproduced reasonably; based on which, we explored the evolutionary mechanisms and the three-dimensional structures of the strong winds associated with the downburst event. It was found that a southwest–northeast-orientated, eastward moving strong squall line was the parent convection system for the downburst event. The downburst-associated convection was deep (from surface to 200 hPa); in the near surface layer, it was mainly associated with positive geopotential height and negative temperature deviations, whereas, at higher levels, it was mainly associated with negative geopotential height and positive temperature deviations. Backward trajectory analysis indicates that the air particles that came from the middle troposphere west of the key region (~61.2% in proportion) were crucial for producing the strong winds of the downburst event. These air particles experienced notable descending processes, during which most of the air particles decreased notably in their potential temperature, while they increased significantly in their specific humidity. The kinetic energy budget analyses denote that, for the region surrounding the location where the tower toppling appeared, the work done by the strong pressure gradient force between the high-pressure closed center (corresponding to intense descending motions) and the low-pressure closed center (corresponding to strong latent heat release) dominated the rapid wind enhancement. [ABSTRACT FROM AUTHOR]

The Bohai Sea (BS) has been experiencing prominent deoxygenation in recent years that forms a typically coastal oxygen depleted region in summer. A three-dimensional coupled physical-biogeochemical model was used in this study to investigate temporal variations of the two separately-developing oxygen depleted zones in the BS. Comparison with observations shows a good model performance for multi-year’s oxygen depletion simulation. Two separately-developing oxygen depleted cores are always identified in these years with a threshold of oxygen concentration less than 3 mg/L. The oxygen depletion in the northern core is generally more severe with larger areas and lower oxygen minima. During the evolution of oxygen depletion, the bottom oxygen concentration decreases more smoothly in the northern core, while fluctuates frequently in the southern core. Nonetheless, the oxygen depletion in both cores fades away almost simultaneously, with a sudden oxygen increase in late summer or early autumn. Oxygen budget estimation indicates that the biological oxygen consumption in the southern core is greater than that in the northern core, but compensated by the oxygen replenishment of oxygen-rich water from the Bohai Strait and vertical diffusion of the water column, which is less in the northern core, so that the oxygen depletion in the northern core is more severe. During oxygen depletion development in June and July, bottom oxygen in the southern core is more susceptible to strong winds than the northern core attributed to differences in topography, with a shallower and smoother bathymetry leading to weaker water column stability in summer. Recognition of characteristics of the two separate oxygen depleted cores would advance understanding spatial pattern of oxygen dynamics and provide a basis for statistical seasonal prediction of coastal oxygen depletion with consideration of spatial heterogeneity.

For nuclear power plants, probabilistic risk assessment (PRA) should be performed not only against earthquake and tsunami, which are critical events especially in Japan, but also other external hazards such as strong wind. The aim of the present study is to develop a practical PRA methodology for sodium-cooled fast reactors (SFRs) against strong wind, paying attention to the final heat sink, ambient air, that removes decay heat under accident conditions. First, this study used Gumbel distributions to estimate hazard curves of the strong wind based on weather data recorded in Japan. Second, it identified important structures, systems and components (SSCs) for decay heat removal, and developed an event tree that results in core damage, focusing on the impacts of missiles (e.g., steel pipes) caused by strong wind. It also identified missiles that can reach SSCs at elevated places, and calculated the fragility of the SSCs against the missiles as a product of two probabilities. One is a probability of the missiles that would enter an inlet or outlet of the decay heat removal system, and another is a probability of failure caused by missile impacts. Finally, it quantified conditional decay heat removal failure probabilities by introducing the fragilities into the event tree. The core damage frequency (CDF) was estimated at about 5 × 10-10/y. The dominant sequence is that strong wind causes offsite power loss and missiles, the missiles penetrate the diesel fuel tank, cause a fire, and the fire increases air temperature around the reactor building where air cooler inlets of decay heat removal systems are installed, leads to loss of power for the diesel generator for forced circulation cooling, resulting in loss of decay heat removal. Through the above, this study has developed the practical PRA methodology for SFRs against strong wind.

Southern Brazil is a region strongly influenced by the occurrence of extratropical cyclones. Some of them go through a rapid and intense deepening and are known as explosive cyclones. These cyclones are associated with severe weather conditions such as heavy rainfall, strong winds, and lightning, leading to various natural disasters and causing socioeconomic losses. This study investigated the interaction between atmospheric and oceanic conditions that contributed to the rapid intensification of the cyclone that occurred near the coast of South Brazil from 29 June to 3 July 2020, causing significant havoc. Hourly atmospheric and oceanic data from the ERA5 reanalysis were employed in this analysis. The results showed that warm air and moisture transportation were key contributors to these phenomena. In addition, the interaction between the jet stream and the cyclone’s movement played a crucial role in cyclone formation and intensification. Positive sea surface temperature anomalies also fueled the cyclone’s intensification. These anomalies increased the surface heat fluxes, making the atmosphere more unstable and promoting a strong upward motion. Due to the strong winds and the heavy rainfall, the explosive cyclone caused substantial impacts on the power services, resulting in widespread power outages, damaged infrastructure, and interruptions in energy distribution. This work describes in detail the cyclone development and intensification and aims at the understanding of these storms, which is crucial for minimizing their aftermaths, especially on energy distribution.

In Guangdong Province, China, known as a hotspot for tropical cyclone (TC) and rainstorm disasters, investigating the role of hazard factors for both TC and rainstorm disasters is of great scientific and operational importance. Daily observational data from meteorological stations along with rainstorm/TC disaster loss data at the county level in Guangdong during 2001–2020 were analyzed to compare the characteristics of rainstorm and TC disasters. During the study period, although non-TC rainstorm rainfall in Guangdong was generally greater than TC rainstorm rainfall, TC disaster losses were double those of rainstorm disasters. Non-TC rainstorms and their losses predominantly occurred during the first flood season, whereas TC disaster primarily occurred in the second flood season. Although regional-average TC rainstorm rainfall was similar to non-TC rainstorm rainfall during the second flood season in Guangdong, it was greater than non-TC rainstorm rainfall in western Guangdong. Additionally, the coastal areas were frequently affected by TC strong winds, resulting in greater TC disaster losses than rainstorm disaster losses. The maximum daily precipitation was significantly correlated with rainstorm disaster losses. In areas influenced by both TC strong winds and rainstorms, TC disaster losses exhibited a significant positive correlation with the daily maximum wind speed, and the combined effect of strong winds and rainstorms led to greater disaster losses than with TC rainstorms alone. These findings emphasize the effects of TC strong wind and storm surges, besides those of heavy rainfall, in coastal areas of China when assessing the risks related to TC disasters.

Extratropical cyclones play a crucial role in balancing the global momentum, energy, and moisture, and also, they shape the extreme weather events over the extra-tropics. As the strongest category of the extratropical cyclones, the explosive extratropical cyclones (EECs) frequently induce severe disasters through their strong surface winds. During the entire lifespan of an EEC, there is a maximum value of its surface wind (i.e. the maximum surface wind; MSW), which processes the greatest destructive power. After nearly a century of research on the EECs, key features about their MSWs still remain vague. In this study, we systematically investigate the EECs’ MSWs over the North Atlantic storm track (NAST) based on the ERA-Interim reanalysis. It is found that, the average intensity of EECs’ MSWs shows a significant increasing trend of ∼0.3 m s ^−1 per 10a. More importantly, for the last 20 years, even larger increasing rates of 1.5 m s ^−1 and 3.5 m s ^−1 per 10a are found in the average and maximum intensities of the EECs’ MSWs, respectively, implying the EECs’ risks increase notably for the NAST. We further clarify the physical mechanisms governing the production of EECs’ MSWs, and then establish a mechanism-based statistical model, which has the potential to predict the MSWs’ annual average intensity. In summary, our study fills a knowledge gap for the EECs’ MSWs, which would have broad implication of the economics and society.

A tidal bore is known for its abrupt change in water flow with a complex and violent leading front. The powerful tidal bore can quickly move up the sloped beach and overtop the seawall, leading to significant damages along the coast. In the past, many coastal seawalls were constructed to shield the coastal regions from the destructive power of tidal bores. The typhoon-induced shear force and pressure imbalance can significantly affect the tidal bore height and its propagation speed. Therefore, it is important to evaluate how strong winds impact the hydrodynamic transformation and overtopping of tidal bore at the seawalls. However, there are few research on this topic. To address the limitations of previous research, this study applies a high-resolution two-phase flow solver to numerically examine how strong winds impacts the overtopping characteristics of tidal bore at coastal seawalls. The effects of main factors, including wind speed, tidal bore height, water depth, and beach slope, are thoroughly examined. Research findings indicate that the presence of wind can cause notable changes in the hydrodynamic evolution and overtopping characteristics of both undular tidal bore and weak breaking tidal bores, whereas its impact on the overtopping characteristics of breaking tidal bore is relatively limited. Simultaneously, the presence of wind can significantly increase the intensities of the undular tidal bore and weak breaking tidal bore at the seawall. The high nonlinear behavior of the breaking tidal bore at the seawall is demonstrated by its impactful intensity when influenced by wind. It is hoped that the present study will enhance knowledge on the hydrodynamic overtopping characteristics of tidal bores in harsh weather conditions. • Hydrodynamic overtopping processes of different types of tidal bores at the seawall under the wind have been numerically investigated by applying a high-resolution two-phase flow solver. • Influences of major factors, such as wind speed, tidal bore height, initial water depth, and beach slope are investigated in detail. • Research results reveal that the wind can noticeably reshape the hydrodynamic evolution and overtopping characteristics of the undular tidal bore and weak breaking tidal bore, except the breaking tidal bore. [ABSTRACT FROM AUTHOR]

Understanding and mitigating wave overtopping are crucial for hinterland safety, yet research primarily focuses on designing coastal structures, with limited attention to structural materials. As global warming intensifies coastal hazards, there is a growing need for resilient infrastructures. A hybrid infrastructure incorporating vegetation alongside concrete may offer a viable solution. In this study, we evaluated the effect of vegetation on wave overtopping reduction under strong winds through hydraulic model experiments simulating extreme storm conditions. The experiments were conducted under the simultaneous action of wind, waves, and vegetation using a two-dimensional wind tunnel flume and vegetation. A higher vegetation density was found to exponentially reduce the overtopping rate. Moreover, dense vegetation was demonstrated to be equivalent to raising the height of protective structures by at least 1.1 m. Furthermore, the increase in overtopping rate by the effects of wind can be compensated by the reduction effects of vegetation. Based on these investigations, an equation was proposed to predict the wave overtopping rate that considers the effects of both wind and vegetation. The results highlight the potential applicability of vegetated coastal protection in future coastal disaster prevention against extreme events with stronger winds and waves that may be induced by climate change. • Wave overtopping rate exponentially decreased as the vegetation density increased. • Dense vegetation was equivalent to raising the dimensionless freeboard by 1.1 m. • Vegetation can decrease the wave overtopping rate increased by wind flow. • An equation was proposed to predict wave overtopping considering wind and vegetation. [ABSTRACT FROM AUTHOR]

Thin and high strength cold-formed steel (CFS) battens and claddings serve as non-combustible elements in roof and wall cladding systems, aligning with the recommendations of Australian bushfire standards. However, they are susceptible to significant damage from heat and strong winds experienced during bushfire events, particularly in the form of batten pull-out failures. Such failures may occur at the screw connections between cladding and battens, or battens and trusses/rafters. However, pull-out failures often occur in the thinner CFS battens, when the screw fastener pulls out of the batten's top flange, leading to the loss of entire cladding and compromising the integrity of the building envelope. This study used finite element modelling of a range of CFS batten configurations to investigate their pull-out failures under combined wind action and bushfire conditions. Finite element models were developed to simulate the pull-out failures at elevated temperatures, validated using experimental results and used in a parametric study to investigate the effects of relevant parameters. Using the results, this study has proposed suitable design equations for predicting the pull-out capacities of CFS battens at elevated temperatures. Engineers can use them to design bushfire safe CFS cladding systems. • Investigated the pull-out failures of CFS battens under the combined wind action and elevated temperatures. • Observed significant reductions in pull-out capacities after 500 ℃, which can lead to an unsafe building envelope. • Developed numerical models with ductile and shear damage criteria for batten configurations at elevated temperatures. • Developed validated numerical models and used in a parametric study to find the influential parameters. • Proposed new pull-out capacity design equations for the screw connections in CFS battens at elevated temperatures. [ABSTRACT FROM AUTHOR]

With the advent of networked rail operations and increasing risks caused by extreme weather conditions, there is an urgent need to enhance the safety early warning and emergency protection for rail under extreme wind environments. By deploying anemometers along the railway and monitoring the surrounding wind speeds, dispatchers can proactively take protective measures to mitigate the impact of severe weather on rail transportation. In particular, accurate time-series forecasting during periods when wind speeds exceed the threshold is critical for railway anomaly monitoring. This study employs Extreme Value Theory (EVT) to determine the threshold for strong winds. In order to identify high wind speeds, memory networks are used to memorize strong wind events in historical data. By combining the Gated Recurrent Unit (GRU) module with the attention mechanism, this study ultimately develops a hybrid neural network model in the prediction of wind speed. Based on real-world datasets of wind speeds along the Hangzhou-Haining intercity railway and along the Norway rail network via meteorological stations, the effectiveness of the hybrid neural network model has been verified by comparing base models. The proposed strong wind speed prediction has practical applications in enhancing early warning and rail safety under complex wind climate. • A hybrid neural network model was proposed for strong wind risk management along the railway. • This paper achieved accurate and automated boundary identification between high and low wind speeds. • Its effectiveness was demonstrated using real-world wind data. [ABSTRACT FROM AUTHOR]

Abstract Weather radars are capable of detecting and displaying storm‐related turbulence as well as precipitation rate with fine spatial resolution and reliable quality. Especially, weather radars can enable the detection of atmospheric conditions in the vicinity of cities and thereby help to notify the strong winds. This article investigates the application of weather radar measurements for predicting strong wind and presents a new method for very short‐term storm prediction. In the proposed method, hidden Markov model (HMM) is used to classify atmospheric conditions to “potentially stormy” and “non‐stormy” states using the available radar data, and semi‐Markov theory is used to estimate the probability of storm occurrence with time. In fact, the probability of transition between “potentially stormy,” “non‐stormy,” and “stormy” states is modeled by a semi‐Markov model, to find the unconditional probability of storm occurrence with time. The model is implemented with the use of the data of Tehran C‐band weather radar and anemometer of Tehran international airport. Verification results show that the precision (forecast accuracy) is around 0.19 and the recall is around 0.67 in the presented classification method.

Cold wave events (CWEs) often cause major economic losses and serious casualties in the cold seasons, making CWEs among the most significant types of disastrous weather. Previous studies have mainly focused on disasters due to abrupt drops in surface temperatures, with less discussion of the strong winds associated with CWEs. Based on an intense CWE that occurred in late December 2020, we investigated the evolutionary mechanisms of the associated strong winds in terms of kinetic energy (KE) budget and evaluated the effects of this CWE on wind power production based on quantitative comparisons with the mean state. The results showed that the CWE occurred under favorable background conditions, which were characterized by a southward-moving transversal trough and a southeastward-moving shortwave trough in the middle troposphere. The surface high ridge that formed around Lake Baikal and the cold front around the southern periphery of the ridge were key factors related to the CWE evolution. The positive work carried out on the horizontal wind by the pressure gradient force that linked a lower tropospheric high-pressure ridge inland and a low-pressure trough offshore and the downward momentum transportation due to the descending motions behind the cold front dominated the enhancement and sustainment of the CWE-associated strong winds. The CWE contributed to wind power production by 1) increasing the wind power density (by an average of ∼1.05-fold) and 2) improving the availability of the wind to generate power, as it reduced the percentage of zero wind power generation by ∼6.4%, while maintaining the high-wind-velocity cut-out percentage.

A strong wind event under clear‐air conditions during the 2018 Winter Olympic and Paralympic games in Pyeongchang, Korea, was examined using various datasets. High spatiotemporal resolution wind information was obtained by Doppler lidars, automatic weather stations, wind profiler, sounding observations, reanalysis datasets under the International Collaborative Experiments for Pyeongchang 2018 Olympic and Paralympic winter games (ICE‐POP 2018). This study aimed to understand the possible mechanisms of localized strong winds across a high mountainous area and on the leeside associated with the underlying large‐scale pattern of a low‐pressure system (LPS). The evolution of surface winds shows quite different patterns, exhibiting intensification of strong winds in the leeside and periodically persistent strong winds in upstream mountainous areas with the approaching LPS. The surface wind speed was intensified from ∼3 to ∼12 m s−1 (gusts were stronger than 20 m s−1 above the ground) at a surface station in the leeside. A budget analysis of the horizontal momentum equation suggested that the pressure gradient force (PGF) contributed from adiabatic warming and the passage of LPS was the main factor in the acceleration of the surface wind in the leeward side of the mountains. The detailed 3D winds revealed that the PGF also modulated the background winds at the mountainous station, which caused persistent strong and periodic winds (range of ∼7 to ∼12 m s−1) related to the channeling effect. The evidence showed that under the same synoptic condition of a LPS, different mechanisms are important for strong winds in determining the strength and persistence of orographic‐induced strong winds under clear‐air conditions. Plain Language Summary: This study examines a strong downslope wind event during ICE‐POP 2018 using Doppler lidars, and various datasets. The 3D winds can be well retrieved, and this is first time to document the mechanisms of strong wind in observational aspect under clear‐air conditions. The pressure gradient force causing by adiabatic warming and channeling effect are key factors to dominate the strong wind. The values of this study are improving our understanding and increasing the predictability of strong wind in Korea. Key Points: A low‐pressure system (LPS) dominated the nature of orographic‐induced strong winds under clear‐air conditionsHigh‐resolution wind fields can be well retrieved by 3D Doppler wind synthesis via "WISSDOM"The effects of pressure gradient force associated with the LPS as well as adiabatic warming and channeling effect are key factors dominating the strong winds [ABSTRACT FROM AUTHOR]

Plant spacing arrangement might benefit hill strength from the impact of strong wind velocity during extreme weather situations. Here, a loading test to evaluate rice hill strength was performed on Ciherang variety grown in square and double row spacing 2:1. The research was conducted at Cilubang village, Dramaga, Bogor, West Java, Indonesia from March to May 2017. Weight holding capacity was evaluated in 85 days after transplanting on four levels of hill height, i.e., 80 cm, 60 cm, 40 cm, and 20 cm above soil level with three-time replication. The results showed that double-spaced hills had 66.0 % ± 3.1 % stronger than those of square spacing at all height measurement. To lodge a hill into 20 cm to 40 cm from soil level, it required 346.7 g to 741.7 g in square spacing, and 555.2 g to 1149.2 g in double row spacing. Stronger hills in double row spacing seemed to correlate with a higher number of tiller and hills architecture; it requires further study in the role of both factors on the hill strength improvement. The present study recommends applying double row spacing to improve rice hill strength especially at a time with a high chance of lodging by strong wind incident.

Extreme weather incidents refer to high rainfall and strong winds have been speculated to be detrimental on rice production. However, researches on the local adaptation to their impact on rice production are limited especially on tropical region like Indonesia. A study was conducted in Pesawaran, West Lampung, North Lampung, and Bandar Lampung using time series data of 2000-2015 and ground checking during extreme weather and normal seasons and its implication on sustainable management. Data were evaluated using multivariate regressions. Results demonstrated that the impact of extreme weather on the reduction of rice production was weak, 0.92%. Shifting on rice production among swampy, irrigated, and dry lands at which covered area of 13.67%, 42.69% and 43.65%, respectively, minimized the impact of the extreme weather. During limited precipitation, irrigated and swamplands had 2.5-3.0 times cropping intensity. Conversely, during La-Nina with excess precipitation, cropping in irrigated and drylands increased by 20 and 58%, respectively. Moreover, the local government maintained annual production improvement by about 5% through expansion of irrigated land, high yielding varieties and inputs subsidies. Considering that incident of extreme weathers tended to occur more frequently, consequently, planting calender utilization and rice variety adapted should be implemented.

The drag coefficient is a crucial parameter in the interaction between the Earth's surface and the atmosphere because it directly determines the momentum flux. This study examines the variation in the drag coefficient with wind speed over the land surface using observations from two typhoon cases and one cold front case. The analysis shows a significant decrease in the drag coefficient, roughness length, and zero plane displacement when the wind speed is greater than approximately 15 m s−1. The drag coefficient is proven to be positively related to the coherence of the turbulent structures. The momentum transport modes changed at 15 m s−1. By regarding the large eddies as scales larger than observation height, it is found that large‐scale coherent structures dominate the momentum transfer in strong wind conditions, while small eddies contribute significantly in low to moderate wind conditions. Momentum transport in such large coherent eddies is inefficient, leading to the reduction of the surface drag. The results suggest that the formation of inefficient large coherent eddies is likely due to the existence of inverse energy cascade. Key Points: The reduction of surface drag coefficient with high wind speed is observed over landThe reducing aerodynamic drag occurs at U10 ${U}_{10}$ > 15 m s−1 over land compared to 30–35 m s−1 over oceansThe reducing surface drag is due to the low vertical transport efficiency of large scale turbulent eddies in high wind conditions [ABSTRACT FROM AUTHOR]

Weather radars are capable of detecting and displaying storm‐related turbulence as well as precipitation rate with fine spatial resolution and reliable quality. Especially, weather radars can enable the detection of atmospheric conditions in the vicinity of cities and thereby help to notify the strong winds. This article investigates the application of weather radar measurements for predicting strong wind and presents a new method for very short‐term storm prediction. In the proposed method, hidden Markov model (HMM) is used to classify atmospheric conditions to "potentially stormy" and "non‐stormy" states using the available radar data, and semi‐Markov theory is used to estimate the probability of storm occurrence with time. In fact, the probability of transition between "potentially stormy," "non‐stormy," and "stormy" states is modeled by a semi‐Markov model, to find the unconditional probability of storm occurrence with time. The model is implemented with the use of the data of Tehran C‐band weather radar and anemometer of Tehran international airport. Verification results show that the precision (forecast accuracy) is around 0.19 and the recall is around 0.67 in the presented classification method. [ABSTRACT FROM AUTHOR]

Abstract This study investigated the representation of surface winds in complex terrain during the passage of Typhoon Sondga (2004) in downscaling simulations with the horizontal grid spacing of 200 m. The mountainous areas in Hokkaido where forest damages occurred in the typhoon event were chosen for the present analysis. The 200 m grid simulations were compared with the simulations with the grid spacing of 1 km. The 200 m grid simulations clearly indicated more enhanced and more frequent extremes both in the stronger and weaker ranges of surface winds than the 1 km grid case. Both in the 200 m grid and 1 km grid cases, the mean and maximum winds in the analysis areas during the simulated time period increase with the increase in the terrain slope angle, but in the 200 m grid case, the relationships of the mean and maximum winds against the terrain slope angle includes wide scatter. In this way, the response of the wind representations to the grid spacing appears differently between the 200 m and 1 km grid cases. A parameter characterized subgrid-scale orography was used to quantify the influences of the terrain complexity on surface winds, demonstrating that the area-maxima and spatial variance of surface winds are more enhanced with the increase in the subgrid-scale orography in the higher-resolution case. It is suggested that the high-resolution simulations at the 200 m grid highlight the fluctuating nature of surface winds in complex terrain, because of the better representation of the model terrain at 200 m. Benefits of the representation of surface winds in simulations at the resolution on the order of 100 m are due to the better representation of complex terrain, which enables to quantitatively assess the impacts of strong winds on forest and natural vegetation in complex terrain.

This article addresses the fault-tolerant control problem for high-speed trains (HSTs) with actuator faults under strong winds. For the healthy system, a non-singular fast terminal sliding mode surface is introduced into the controller, which ensures the system fast converge to the equilibrium point with finite time, and the radial basis function neural network (RBFNN) with the adaptive compensation term of the error is used to approximate the unknown nonlinear disturbances of the train system in strong winds and predict the time delay generated in the train communication network. Through the RBFNN observer established specifically for actuator failures, the real effective factors are identified. Combining with the identified effective factors and predicted time delay, an adaptive fault-tolerant sliding mode control method is established for train systems. With dynamic parameters and position update strategy guided by negative gradient thought, an improved particle swarm optimization algorithm is proposed to optimize the uncertain parameters of control method, which weakens the chattering phenomenon from the sliding mode controller and improves the control accuracy. Simulation results show that the proposed method has better tracking performance and real-time performance compared with other fault-tolerant control methods under various operating conditions, which ensures the running safety of HSTs under different strong winds.

Window glass of the train was broken several times when running in the strong wind/sandy areas, causing safety risks to passengers and serious problems to the operation of the train. The aerodynamic performances of the train with broken windows in strong wind condition are uncertain. These problems remain the challenging research issues. To study these issues, the influence of the broken windows on the aerodynamic performances of the train model was analyzed using three-dimensional numerical simulation methods. The results showed that the aerodynamic forces on the second passenger car first decreased and then increased within a very short period when the two middle windows on the windward side had been broken. However, the side force and the overturning moment increased sharply when the wind angle was increasing. In addition, the number of broken window glass has significant effects on train aerodynamics when running in cross wind area, and the absolute value of the side force and of the overturning moment increased significantly with the increase in the number of broken windows on windward side.

The downburst events have been a research focus for decades, as their associated disastrously strong winds pose a great threat to aviation, the shipping industry, agriculture, and the power industry. On 14 May 2021, a series of severe convection occurred in middle and eastern China, during which six 500-kilovolt transmission line towers in Zhejiang were toppled down by a downburst event, resulting in a large range of power outages. By using the Weather Research and Forecasting (WRF) model version 4.4, key features of the downburst event were reproduced reasonably; based on which, we explored the evolutionary mechanisms and the three-dimensional structures of the strong winds associated with the downburst event. It was found that a southwest–northeast-orientated, eastward moving strong squall line was the parent convection system for the downburst event. The downburst-associated convection was deep (from surface to 200 hPa); in the near surface layer, it was mainly associated with positive geopotential height and negative temperature deviations, whereas, at higher levels, it was mainly associated with negative geopotential height and positive temperature deviations. Backward trajectory analysis indicates that the air particles that came from the middle troposphere west of the key region (~61.2% in proportion) were crucial for producing the strong winds of the downburst event. These air particles experienced notable descending processes, during which most of the air particles decreased notably in their potential temperature, while they increased significantly in their specific humidity. The kinetic energy budget analyses denote that, for the region surrounding the location where the tower toppling appeared, the work done by the strong pressure gradient force between the high-pressure closed center (corresponding to intense descending motions) and the low-pressure closed center (corresponding to strong latent heat release) dominated the rapid wind enhancement.

Over previous decades, the United States has been plagued by severe winter storms or blizzards, which caused millions of dollars in damages. However, the historical trend of blizzard events and the possible impacts of future global climate change on blizzard occurrences remain unclear. In this study, we analyzed historical blizzard occurrences using the observed storm event database, which shows that the Northern Plains, such as North Dakota, South Dakota, and Minnesota, had the most blizzard activities over the past 25 years. No significant trend in blizzard occurrence is found in those regions. When considering blizzards as compound events of strong wind and extreme snowfall, we estimated blizzard occurrences based on wind speed and snowfall in climate datasets, including Automated Surface Observing Systems wind speed, national gridded snowfall analysis, ERA5 reanalysis and historical simulations of 19 models in Coupled Model Intercomparison Project phase 6 (CMIP6), which show a good agreement with the observations with respect to the climatology of blizzard occurrence. In the near-term and long-term future under two emission scenarios, CMIP6 projections suggest decreases in both strong wind and extreme snowfall events, eventually leading to a significantly reduced frequency of compound events. Significant decreases in blizzard occurrence are found in the Northern Plains and Upper Midwest, suggesting potentially reducing the risk of winter hazards over those regions in a warming climate.

Wind velocity is usually assumed to obey a stationary stochastic process in wind engineering, and this may cause significant bias in describing extremely severe strong wind such as typhoons and thunderstorms. To take into account the non-stationary characteristics of extreme wind, a novel evolutionary power spectral density (EPSD) model is proposed, and the spectral representation method (SRM) is introduced to simulate the whole process of strong winds. Firstly, the wavelet transform (WT) method is adopted to capture the three-dimensional time-varying properties of the low-frequency mean winds, and the associated turbulence features, including turbulent intensity, gust factor, probability density function, and power spectrum, are analyzed in depth. Secondly, the measured horizontal EPSD of strong winds are estimated. Thirdly, the performance of the proposed EPSD model is validated. Finally, the whole process of non-stationary strong winds are simulated and discussed. The results show that the proposed EPSD models are in good agreement with the measured EPSD, and the time-frequency features of the power spectrum of the simulated winds are well reproduced, which provides a powerful tool for large eddy simulation and wind engineering studies under non-stationary extreme wind climate., Competing Interests: We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (© 2024 The Authors.)

Extreme weather incidents refer to high rainfall and strong winds have been speculated to be detrimental on rice production. However, researches on the local adaptation to their impact on rice production are limited especially on tropical region like Indonesia. A study was conducted in Pesawaran, West Lampung, North Lampung, and Bandar Lampung using time series data of 2000-2015 and ground checking during extreme weather and normal seasons and its implication on sustainable management. Data were evaluated using multivariate regressions. Results demonstrated that the impact of extreme weather on the reduction of rice production was weak, 0.92%. Shifting on rice production among swampy, irrigated, and dry lands at which covered area of 13.67%, 42.69% and 43.65%, respectively, minimized the impact of the extreme weather. During limited precipitation, irrigated and swamplands had 2.5-3.0 times cropping intensity. Conversely, during La-Nina with excess precipitation, cropping in irrigated and drylands increased by 20 and 58%, respectively. Moreover, the local government maintained annual production improvement by about 5% through expansion of irrigated land, high yielding varieties and inputs subsidies. Considering that incident of extreme weathers tended to occur more frequently, consequently, planting calender utilization and rice variety adapted should be implemented. [ABSTRACT FROM AUTHOR]

Momentary discomfort caused by high-speed trains passing through complex terrain sections under strong wind conditions has become an urgent engineering problem in China. However, few scholars or research institutions have focused on this topic, and there are no standards for the evaluation of such discomfort. Therefore, in this study, the suitability of existing vibration comfort-evaluation methods under strong wind conditions was investigated by a full-scale test, and the characteristics of the car-body vibration and momentary discomfort under strong wind conditions were analyzed. It was indicated that low-frequency transient roll motion and transverse motion of the car-body are the main causes of discomfort, and the comfort-assessment methods in European standard (EN-12299) could not be directly used under these conditions. Consequently, an evaluation method for momentary discomfort caused by high-speed trains passing through complex terrain sections under strong wind conditions is suggested. [ABSTRACT FROM AUTHOR]

Window glass of the train was broken several times when running in the strong wind/sandy areas, causing safety risks to passengers and sericus problems to the operation of the train. The aerodynamic perfonnances of the train with broken windows in strong wind condition are uncertain. These problems remain the challenging research issues. To study these issues, the influence of the broken windows on the aerodynamic performances of the train model was analyzed using three-dimensional numerical simulation methods. The results showed that the aerodynamic forces on the second passenger car first decreased and then increased within a very short period when the two middle windows on the windward side had been broken. However, the side force and the overturning moment increased sharply when the wind angle was increasing. In addition, the number of broken window glass has significant effects on train aerodynamics when running in cross wind area, and the absolute value of the side force and of the overturning moment increased significantly with the increase in the number of broken windows on windward side. [ABSTRACT FROM AUTHOR]

Real-time monitoring of overturning coefficients is very important for ensuring the safety of high-speed trains passing through complex terrain sections under strong wind conditions. In recent years, the phenomenon of "car swaying" that occurs when trains pass through the complex terrain has brought new challenges to ensuring the safety and riding comfort of passengers. In China, more and more high-speed trains are facing strong wind environments when running in complex terrain sections. However, due to the limitation of objective conditions, so far, only a few economical and effective methods of measurement have been developed that are suitable for real-time monitoring of the overturning coefficient of commercial vehicles. Therefore, considering the applicability and universality of such a monitoring method, this study presents a method for measuring the overturning coefficient of trains using the primary suspension system under strong winds. A vehicle test was carried out to verify the accuracy of the method. The results show that after correction, the overturning coefficient obtained from the primary suspension system is generally consistent with the overturning coefficient obtained from the instrumented wheelset. The method of measuring the overturning coefficient of trains in strong wind environments with the primary suspension system is, thus, proven feasible. [ABSTRACT FROM AUTHOR]

This study investigated the representation of surface winds in complex terrain during the passage of Typhoon Sondga (2004) in downscaling simulations with the horizontal grid spacing of 200 m. The mountainous areas in Hokkaido where forest damages occurred in the typhoon event were chosen for the present analysis. The 200 m grid simulations were compared with the simulations with the grid spacing of 1 km. The 200 m grid simulations clearly indicated more enhanced and more frequent extremes both in the stronger and weaker ranges of surface winds than the 1 km grid case. Both in the 200 m grid and 1 km grid cases, the mean and maximum winds in the analysis areas during the simulated time period increase with the increase in the terrain slope angle, but in the 200 m grid case, the relationships of the mean and maximum winds against the terrain slope angle includes wide scatter. In this way, the response of the wind representations to the grid spacing appears differently between the 200 m and 1 km grid cases. A parameter characterized subgrid-scale orography was used to quantify the influences of the terrain complexity on surface winds, demonstrating that the area-maxima and spatial variance of surface winds are more enhanced with the increase in the subgrid-scale orography in the higher-resolution case. It is suggested that the high-resolution simulations at the 200 m grid highlight the fluctuating nature of surface winds in complex terrain, because of the better representation of the model terrain at 200 m. Benefits of the representation of surface winds in simulations at the resolution on the order of 100 m are due to the better representation of complex terrain, which enables to quantitatively assess the impacts of strong winds on forest and natural vegetation in complex terrain. [ABSTRACT FROM AUTHOR]

We evaluated effects of strong typhoons on populations of a gall midge Pseudasphondylia neolitseae (Diptera: Cecidomyiidae) and its associated arthropods through leaf fall of the host plant, Neolitsea sericea (Lauraceae). The very strong typhoon No. 13 in 1985 ("8513‐Pat") caused heavy leaf fall particularly on forest edge trees, resulted in the larval death of gall midge and its endoparasitoid Gastrancistrus sp. (Hymenoptera: Pteromalidae). The typhoons were not directly responsible for the larval death of an ectoparasitoid Bracon tamabae (Hymenoptera: Braconidae) and a successor Lasioptera yadokariae (Diptera: Cecidomyiidae) that utilizes vacant galls after the departure of inhabitants. However, reduction in the number of galls possibly made their searching behavior for oviposition sites inefficient because their abundance relies on the gall density. The heavy leaf fall promoted lammas shoot production, which caused the reduction of number and length of the following spring shoots. The shortage of spring shoots must be influential to the gall midge females in searching oviposition sites, and the short spring shoots were not useful for oviposition and larval boring by Oberea hebescens (Coleoptera: Cerambycidae). We compared strength of the effects between the typhoons that attacked Kagoshima in 1985 and 1993, and Okinawa in 2015 and 2018, and concluded that typhoons with the maximum instantaneous wind velocity exceeding 50 m/s caused heavy leaf fall and lammas shoot production on N. sericea trees growing at forest edge but not on those inside forest. [ABSTRACT FROM AUTHOR]

A modified lattice hydrodynamic model is proposed, in which the impact of strong wind and the optimal estimation of flux difference integral are simultaneously analyzed. Based on the control theory, the stability condition is acquired through linear analysis. The modified Korteweg-de Vries (mKdV) equation is derived via nonlinear analysis, in order to express a description of the evolution of density waves. Then, numerical simulation is conducted. From the simulation results, strong wind can largely influence the traffic flow stability. The stronger the wind becomes, the more stable the traffic flow is, to some extent. Similarly, the optimal estimation of flux difference integral also contributes to stabilizing traffic flow. The simulation results show no difference compared with the theoretical findings. In conclusion, the new model is able to make the traffic flow more stable.

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This study focuses on the analysis of the effect of meteorological disasters on film plastic greenhouses by typhoons, heavy snow, strong wind, and heavy rain. The data of meteorological disasters from 1998 to 2015 were analyzed on provincial basis to calculate the damage rate depending on the weather cause. The cumulative damage area is 20 279 hm². The damage rates of typhoons, heavy snow, strong wind, and heavy rain are 46.4%, 47.4%, 2.5%, and 3.8%, respectively. The damage index of the greenhouse, which is the ratio of the greenhouse area to the cumulative damage area, was proposed to estimate the disaster risk for 17 administrative districts. The damage index data and the cumulative damage areas were divided using the Jenks' Natural Breaks method. The average damage index is 0.66, and the damage indices are high in the metropolitan cities. [ABSTRACT FROM AUTHOR]

Current structural design codes usually treat multiple hazards separately, and probabilistic backbones are rare for extreme hazard combinations, e.g., earthquake and strong wind, which may cause unforeseen damage to engineering structures exposed to multiple extreme hazards during their lifecycles. This study presents an innovative copula-based approach to construct the joint cumulative distribution function (JCDF) of the peak ground acceleration (PGA) and strong wind speed (V). Six commonly used Archimedean copulas are applied to bond the JCDF with the corresponding marginal cumulative distribution functions (MCDFs) of PGA and V. A total of 76 low-probability-high-consequence extreme events with a simultaneously occurring earthquake and strong wind are abstracted from data recorded from 1971–2017 in Dali Prefecture, China. The statistical analysis results show that the Frechet and truncated Weibull distributions are the optimal expressions for the marginal distributions of PGA and V , respectively, while the Joe Archimedean copula can yield good JCDF estimation. Monte Carlo simulation is employed to establish a target dependent multihazard database that can be used for the performance-based design of engineering structures against multiple natural hazards. A high-rise building is used to study the performance under the multihazard of an earthquake and strong wind. The results show that the maximum inter-story drift ratio of the building under multiple hazards increases by 14.4–21.3% compared with the structural response induced by an earthquake alone. [ABSTRACT FROM AUTHOR]