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The Lanzhou-Xinjiang high-speed railway (HSR) traverses areas of the Gobi Desert where extremely strong winds are frequent. These strong winds cause sand/gravel hazards, an unaddressed issue that often seriously compromises the safe operation of the HSR. This paper studies the mechanisms leading to wind-blown sand hazards and the outcomes of sand control projects in these areas. The main findings are as follows: (1) Cold northern airflows over the Tian Shan mountain range are accelerated by the wind tunnels and downslope effect as they pass over complex terrain comprising passes, gullies, and proluvial fans. Consequently, the wind intensity often increases two- to threefold, creating frequent high-speed winds that lead to severe sand damage along the HSR. (2) In the Gobi areas with extremely strong winds, sand grains can be lifted as high as 9 m from the ground into the air, far higher than in other areas of the desert. The sand transport rate decreases exponentially with increasing height. Both wind speed and particle size determine saltation height. Coarser particles and stronger winds provide the particles with a higher kinetic energy as they collide with the ground. In the wind zones of Baili and Yandun, the analysed study areas, the saltation layer height of wind-blown sand/gravel exceeds 3 and 2 m, respectively. (3) Based on the above findings, recently emerging sand control materials, suitable for the areas of interest, were screened and developed. Furthermore, under the proposed principle of ‘supplementing blocking with trapping’, a comprehensive sand control measure was established, featuring sand-blocking belts comprised of multiple rows, and high, vertical sand-trapping installations with a large grids size. The installed system showed a high efficacy, reducing sand transport rate by 87.87% and significantly decreasing the deposition of sand along a trial section of the HSR.

The characteristics of eolian sand activity are greatly influenced by the wind regime, and wind regimes have been changing around the world in response to climate change. This has also been true in the desert area of northwestern China since 1965, and these changes have changed the region’s landforms, sandstorm frequency, and desertification. In this study, we analyzed the temporal and spatial variation of the region’s near-surface wind field since 1965. We found an average annual wind speed during this period of 1.7 m s−1, with a decreasing trend from 1965 to 2000 and an increasing trend from 2000 to 2015. The maximum rate of decrease occurred in the spring and in the eastern Taklimakan Desert. The variation of the average wind speed depended on the frequency of winds strong enough to entrain sand (with a wind speed > 6 m s−1). We also found that variations of the drift potential were primarily controlled by three prevailing wind groups (winds from the northwest, north, and northeast), but showed complex changes between seasons and regions. The wind direction in the Taklimakan Desert is characterized by two characteristics of branch and steering, the branch line is swinging in the direction of the east and the west (81.5° E~84° E). The changes in wind speed were mainly caused by a decreased frequency of strong winds, precipitation, and urban development. However, the variation of wind speed had less impact on the desert environment than the variation of wind direction.

Persistent strong winds are a common feature within the near‐surface layer of tropical cyclones, which can induce pronounced horizontal motion as raindrops descend. However, current state‐of‐art microphysics schemes typically only consider the vertical motion of raindrops, ultimately failing to accurately simulate the collisional outcomes of raindrops and the associated raindrop size distributions (RSDs) under strong winds. For instance, the original bin microphysics scheme was unable to successfully reproduced the evolution of RSDs with decreasing height, as measured from the multi‐layer observations during the landfall of Typhoon Pakhar (2017). Thus, this study introduces a modified bin microphysics scheme that incorporates the influence of horizontal wind speeds, vertical wind shear and smaller‐scale turbulence on the total movement velocity (including horizontal and vertical components) of raindrops, and consequently on their collisional outcomes. This modification demonstrates a remarkable improvement in the representation of the intrinsic variation in RSDs with decreasing height under strong‐wind conditions. Plain Language Summary Microphysical processes play a critical role in determining rainfall intensity, so accurately simulating these processes is essential for improving the accuracy of rainfall forecasts. However, current state‐of‐art microphysics schemes primarily consider only the vertical motion of raindrops and the outcomes of gravitational collision, which can lead to forecast inaccuracies. Based on multi‐layer observations, this study found that raindrops exhibit sub‐terminal velocity (smaller than their terminal velocity) and pronounced horizontal motion, influenced by strong horizontal wind speeds, vertical wind shear and smaller‐scale turbulence within the near‐surface layer of tropical cyclones. These factors can significantly change the sedimentation and collisional coalescence/breakup processes of raindrops. Incorporating the effects of strong winds into the parameterization of the coalescence/breakup processes within a bin microphysics scheme has substantially improved the simulation of the observed vertical evolution of RSDs with decreasing height. These findings will enhance the understandings and capacity to reproduce microphysical processes under strong‐wind conditions. Key Points The movement of raindrops is significantly influenced by the winds, leading to the changes in raindrop sedimentation and coalescence/breakup Current microphysics schemes only consider the vertical motion of raindrops, failing to simulate the microphysics under strong winds A bin microphysics scheme was updated to include the wind effects on raindrop total motion and collisions, improving raindrop size distribution representation

Several major storms pounded western Europe in January 2018, generating large damages and casualties. The two most impactful ones, Eleanor and Friederike, are analysed here in the context of climate change. Near surface wind speed station observations exhibit a decreasing trend in the frequency of strong winds associated with such storms. High-resolution regional climate models, on the other hand, show no trend up to now and a small increase in storminess in future due to climate change. This shows that factors other than climate change, which are not in the climate models, caused the observed decline in storminess over land. A large part is probably due to increases in surface roughness, as shown for a small set of stations covering the Netherlands and in previous studies. This observed trend could therefore be independent from climate evolution. We concluded that human-induced climate change has had so far no significant influence on storms like the two mentioned. However, all simulations indicate that global warming could lead to a marginal increase (0 %–20 %) in the probability of extreme hourly winds until the middle of the century, consistent with previous modelling studies. This excludes other factors, such as surface roughness, aerosols, and decadal variability, which have up to now caused a much larger negative trend. Until these factors are correctly simulated by climate models, we cannot give credible projections of future storminess over land in Europe.

Typhoon-induced hazards in South Korea exhibit strong spatial heterogeneity, requiring localized assessments to support impact-based early warning. This study develops a district-level typhoon hazard framework by integrating high-resolution meteorological fields with structural and hydrological vulnerability indicators. Two impact-oriented indices were formulated: the Strong Wind Risk Index (SWI), based on 3 s gust wind intensity and building-age fragility, and the Heavy Rainfall Risk Index (HRI), combining probable maximum precipitation with permeability and river-network density. Hazard levels were classified into four categories, Attention, Caution, Warning, and Danger, using district-specific percentile thresholds consistent with the THIRA methodology. Nationwide analysis across 250 districts revealed a pronounced coastal–inland gradient: mean SWI and HRI values in Busan were approximately 1.9 and 6.3 times higher than those in Seoul, respectively. Sub-district mapping further identified localized hotspots driven by topographic exposure and structural vulnerability. By establishing statistically derived, region-specific thresholds, this framework provides an operational foundation for integrating localized hazard interpretation into Korea’s Typhoon Ready System (TRS). The results strengthen the scientific basis for adaptive, evidence-based early warning and climate-resilient disaster-risk governance.

Strong offshore wind events (SOWEs) occur frequently near the Antarctic coast during austral winter. These wind events are typically associated with passage of synoptic- or meso-scale cyclones, which interact with the katabatic wind field and affect sea ice and oceanic processes in coastal polynyas. Based on numerical simulations from the coupled Finite Element Sea-ice Ocean Model (FESOM) driven by the CORE-II forcing, two coastal polynyas along the East Antarctica coast––the Prydz Bay Polynya and the Shackleton Polynya are selected to examine the response of sea ice and oceanic properties to SOWEs. In these polynyas, the southern or western flanks of cyclones play a crucial role in increasing the offshore winds depending on the local topography. Case studies for both polynyas show that during SOWEs, when the wind speed is 2–3 times higher than normal values, the offshore component of sea ice velocity can increase by 3–4 times. Sea ice concentration can decrease by 20–40%, and sea ice production can increase up to two to four folds. SOWEs increase surface salinity variability and mixed layer depth, and such effects may persist for 5–10 days. Formation of high salinity shelf water (HSSW) is detected in the coastal regions from surface to 800 m after 10–15 days of the SOWEs, while the HSSW features in deep layers exhibit weak response on the synoptic time scale. HSSW formation averaged over winter is notably greater in years with longer duration of SOWEs.

The trends in the climate normals of the frequency of strong winds that were registered during the period of modern climate warming (1961–2020) over various parts of the Northern Sea Route are studied. The information of the ERA5 reanalysis is used. The total duration of winds exceeding 10.8 m/s during each month is used as an indicator characterizing the frequency of strong winds. Based on these data, the climate normals of the frequency of strong winds for the base (1961–1990) and modern (1991–2020) periods are determined. The areas of the Northern Sea Route with an increase in climate normals for the modern climate period in relation to similar indicators for the base climate period are identified.

The transition between the stable and the near-neutral regimes corresponding to weak and strong winds in the stable boundary layer is investigated using four one-dimensional numerical models with increasing numbers of prognostic equations for turbulent variables. The basic state for all the models includes prognostic equations for mean horizontal wind speed, and air and surface temperatures. The simplest model of the four has turbulence variables parametrized using a long-tail stability function and the gradient Richardson number. The complexity of the other three models increases by introducing one more prognostic equation to each model to reduce the number of parametrized turbulent variables: a prognostic equation for turbulent kinetic energy (TKE, e model), an additional prognostic equation for heat fluxes (e-\\[F_{H}\\] model), and an additional prognostic equation for temperature variances (e-\\[F_H\\]-\\[\\sigma _{\\theta }\\] model). Results for all modells are similar in the strong-wind regime. The two stability regimes can be identified in the relationship between the turbulence velocity scale derived from TKE and mean wind speed from the three models with resolved TKE. However, the weak-wind regime can only be resolved with heat fluxes and temperature variance solved by prognostic equations. Simulations with the removal of the buoyancy term associated with heat fluxes in the TKE equation only result in the strong-wind regime, showing that this term controls the regime transition.

A 5-yr climatology of westerly wind events in Owens Valley, California, is derived from data measured by a mesoscale network of 16 automatic weather stations. Thermally driven up- and down-valley flows are found to account for a large part of the diurnal wind variability in this approximately north–south-oriented deep U-shaped valley. High–wind speed events at the western side of the valley deviate from this basic pattern by showing a higher percentage of westerly winds. In general, strong westerly winds in Owens Valley tend to be more persistent and to display higher sustained speeds than strong winds from other quadrants. The highest frequency of strong winds at the valley floor is found in the afternoon hours from April to September, pointing to thermal forcing as a plausible controlling mechanism. However, the most intense westerly wind events (westerly windstorms) can happen at any time of the day throughout the year. The temperature and humidity variations caused by westerly windstorms depend on the properties of the approaching air masses. In some cases, the windstorms lead to overall warming and drying of the valley atmosphere, similar to foehn or chinook intrusions. The key dynamical driver of westerly windstorms in Owens Valley is conjectured to be the downward penetration of momentum associated with mountain waves produced by the Sierra Nevada ridgeline to the west of the valley.

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.