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This paper reviews the numbers of tropical cyclones in the southern Indian Ocean, and the land-falling cyclones that have impacted the Pilbara and Gascoyne coastlines of Western Australia since 1970, with particular emphasis on those of Category 4 strength and above. It shows reductions in impacts of severe cyclones on that coastline in the most recent two decades. Nearly as many severe cyclones have impacted the coast outside the current northern boundary of Region D in AS/NZS 1170.2 as have occurred within that boundary, suggesting the limits of Region D may need reviewing. Recorded and corrected extreme wind gusts exceeding 22 m/s from eight coastal stations have been processed as a group, and individually for 3 stations with long records. This indicates that the extreme value distribution in the draft standard DR AS/NZS 1170.2:2020 is quite adequate, without any additional factors, but the predicted extreme wind speeds for Carnarvon are well under the Region D specifications. The calculated wind direction multipliers for Region D show higher values from east and northeast; this can be explained by the wind directions generated by the clockwise rotations created by the cyclonic vortices, as the storms cross the coastline, or as they pass along the coastline at near full strength. [ABSTRACT FROM AUTHOR]

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This paper proposes a computational fluid dynamics (CFD) model, along with dimensionless quantitative assessment standard—air pollution residual time (APRT) for the evaluation of local haze-fog (HF) dispersion in a built environment. A low APRT value ensures good ventilation. A building group model that comprises high-rise business building, mid-rise office buildings, low-mid-rise residential buildings (at the center of the building group), a mid-rise recreational center, and a local road (open terrain), was scaled down (1:100) to simulate the HF dispersion process. The orientation of the building group was numerically modified to generate a wind incidence normal to the high-rise building, mid-rise buildings, recreational center, and road. The results showed that the orientation of the building group largely determines the APRT. The most favorable orientation can reduce APRT by more than 50%. Our results strongly suggested that in order to reduce the consequential negative effect of air pollution, future urban designs should undergo a comprehensive ventilation assessment to ensure a low APRT value. [ABSTRACT FROM AUTHOR]

Most wind turbines within wind farms are set up to face a pre-determined wind direction. However, wind directions are intermittent in nature, leading to less electricity production capacity. This paper proposes an algorithm to solve the wind farm layout optimization problem considering multi-angular (MA) wind direction with the aim of maximizing the total power generated on wind farms and minimizing the cost of installation. A twostage genetic algorithm (GA) equipped with complementary sampling and uniform crossover is used to evolve a MA layout that will yield optimal output regardless of the wind direction. In the first stage, the optimal wind turbine layouts for 8 different major wind directions were determined while the second stage allows each of the previously determined layouts to compete and inter-breed so as to evolve an optimal MA wind farm layout. The proposed MA wind farm layout is thereafter compared to other layouts whose turbines have focused site specific wind turbine orientation. The results reveal that the proposed wind farm layout improves wind power production capacity with minimum cost of installation compared to the layouts with site specific wind turbine layouts. This paper will find application at the planning stage of wind farm. [ABSTRACT FROM AUTHOR]

The analysis of circular data is the main subject in many disciplines, such as meteorology and oceanography. In this article, we introduce a new multimodal skew‐circular model as an extension of the circular beta distribution. We propose a truncated power smoothing spline for modeling the skewness parameter and identifying significant factors of the asymmetry. A Markov chain Monte Carlo scheme is provided to perform statistical inference from a Bayesian perspective. Then, the performance of our modeling methodology to analyze specific circular responses is assessed through several simulation studies. To illustrate the usefulness of the new model in practical applications, we analyze measurements on the wind and wave directions in Norway. We also fit various regression models to show that the cubic smoothing spline approach performs better than competitive models in practical applications. Findings, based on prediction values, confirm that the proposed model can reasonably fit multimodal skewed‐circular responses. [ABSTRACT FROM AUTHOR]

In this paper we present a detailed comparison of the prediction error based model selection criteria in circular random effects models. The study is primarily motivated by the need for an understanding of their performance in real life ecological and environmental applications. Prediction errors are based on posterior predictive distributions and the model selection methods are adjusted for the circular manifold. Plug-in estimators of the circular distance parameters are also considered. A Monte Carlo experiment scheme taking the account of various realistic ecological and biological scenarios is designed. We introduced a coefficient that is based on conditional expectations to examine how the deviation from von Mises (vM) distribution, the standard choice in applications, effects the performances. Our results show that the performances of widely used circular predictive model selection criteria mostly depend on the sample size as well as within-sample-correlation. The approaches and selection strategies are then applied to investigate orientational behaviour of Talitrus saltator under the risk of dehydration and direction of wind with respect to associated atmoshperic variables. [ABSTRACT FROM AUTHOR]

Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as vertical wind field measurement. In order to verify the accuracy of the Doppler wind lidar, the major domestic Doppler wind lidar manufacturers were organized to compare the Minute-level average wind speed and direction data measured by the lidars to which measured by meteorological gradient tower and L band Sounding radar in Shenzhen and Zhangjiakou, respectively. The result of comparison with the wind cup on the meteorological gradient tower is in good agreement, the correlation coefficient of wind speed is close to or higher than 90%, and the maximum standard deviation of the wind direction is about 7 ° except the inflection point. When the L-band sounding radar is used as a reference for the lidar equipment which joint the comparison. The system difference and standard deviation of daily wind speed and direction vary greatly, and the reliability is poor. At the same time, it was founded that compared with the 1-minute average data, when the 10-minute average data were used for comparison, the system deviation and standard deviation were reduced. That mean the results were more stable and reliable. The comparison results show that the technical indicators of several domestic lidar equipment are equivalent to windcube indicators made by Vaisala and complying with the World Meteorological Organization's requirements for the Coherent Doppler Lidar indicator for near-term weather forecasts. It shows the lidars are reliable to obtain wind speed and direction parameters at different altitudes in real time. [ABSTRACT FROM AUTHOR]

HF radars are now an important part of operational coastal observing systems where they are used primarily for measuring surface currents. Their use for wave and wind direction measurement has also been demonstrated. These measurements are based on physical models of radar backscatter from the ocean surface described in terms of its ocean wave directional spectrum and the influence thereon of the surface current. Although this spectrum contains information about the local wind that is generating the wind sea part of the spectrum, it also includes spectral components propagating into the local area having been generated by winds away from the area i.e., swell. In addition, the relationship between the local wind sea and wind speed depends on fetch and duration. Thus, finding a physical model to extract wind speed from the radar signal is not straightforward. In this paper, methods that have been proposed to date will be briefly reviewed and an alternative approach is developed using machine learning methods. These have been applied to three different data sets using different radar systems in different locations. The results presented here are encouraging and proposals for further development are outlined.

Biogeographical barriers to gene flow are central to plant phylogeography. In East Asia, plant distribution is greatly influenced by two phylogeographic breaks, the Mekong-Salween Divide and Tanaka-Kaiyong Line, however, few studies have investigated how these barriers affect the genetic diversity of species that are distributed across both. Here we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia , a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern China. Demographic and migration hypotheses were tested using coalescent-based approaches. Limited historical gene flow was observed between the western and eastern groups of P. rotundifolia , but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line, manifesting in clear admixture and high genetic diversity in the central group. Wind-borne pollen and seeds may have facilitated the dispersal of P. rotundifolia following prevalent northwest winds in the spring. We also found that the Hengduan Mountains, where multiple genetic barriers were detected, acted on the whole as a barrier between the western and eastern groups of P. rotundifolia . Ecological niche modeling suggested that P. rotundifolia has undergone range expansion since the last glacial maximum, and demographic reconstruction indicated an earlier population expansion around 600 Ka. The phylogeographic pattern of P. rotundifolia reflects the interplay of biological traits, wind patterns, barriers, niche differentiation, and Quaternary climate history. This study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas., Competing Interests: The authors declared that they have no conflicts of interest to this work., (© 2024 Kunming Institute of Botany, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.)

Marine dynamics plays an important role in understanding the variations in offshore suspended sediment distribution and transport direction. In this study, variations in total suspended sediment concentration (TSSC) over Terrebonne Bay in the northern Gulf of Mexico were investigated by using remote sensing technology in relation to ocean-atmospheric dynamics. The terrestrial rainfall/runoff and river discharge in the lower Mississippi River estuarine area during the study period played an important role in the surface TSSC distribution. In most cases, the wave period and wind speed affected TSSC and its distribution. There was an inverse relationship between TSSC and wave period, but wind speed exhibited a positive relationship with TSSC distribution; however, there was a slight delay. The southeast (onshore) wind accounted for 57.0% of the wind direction over the study area and played a major role in the control of the surface sediment concentration in Terrebonne Bay in July 2010. The onshore wind lifted the underlying sediment, increasing the TSSC at the sea surface. The maximum TSSC was 1056.47 mg/l in the southeast direction (96.75°, onshore) on July 1. Other higher TSSCs were also observed in the southeast wind direction: 996.38, 820.55, and 605.27 mg/l with wind directions of 99.63, 127.33, and 120.17° on 2, 5, and 6 July 2010, respectively. The correlation coefficients between TSSC and wave period and wind speed were 0.45 and 0.47, respectively (significant level of 99%). The sediment concentration in the coastal area was related to coastal erosion and river discharge. The sediment transport not only was related to the physical properties of the sediment, but also depended on the flow velocity. The wind-driven flow field is one of the main factors that drive sediment transport. The sediments in the estuary and bay have many similarities in their dynamic environment and development evolution. The study of the dynamic response of offshore sediments is a supplement to the theory of sediment transport in the estuary and coastal zones. The study of the relationship between ocean dynamics and sediment transport can provide a reference for the site selection of offshore engineering structures. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the wind effects, wind velocity and wind direction, on heat losses from a receiver with the longitudinal tilt angle of small-scale linear Fresnel reflectors for urban applications. In urban applications, the area required to install a solar collector is a critical parameter, therefore the parameter given by the energy-to-area ratio must reach its maximum value. Different combinations of longitudinal tilt angles are analyzed and compared with the typical configuration of a large scale linear Fresnel reflector (C1 configuration). The analysis is performed by SolidWorks Flow Simulation for different wind velocities and wind directions. Heat losses from the receiver have been estimated using a 3-D computational fluid dynamics model. Based on the numerical simulation of the receiver, the heat loss analysis has been calculated for several wind velocities, wind directions, and maximum energy-to-area ratio configurations. The effect of wind direction on heat losses is almost negligible. Although, heat losses are slightly higher in the North wind direction in most simulations. It will be demonstrated that the heat losses dramatically increase with a maximum energy-to-area ratio configuration, with the increase in longitudinal angle and, obviously, with the wind velocity. On the other hand, heat losses are higher at those locations with greater maximum energy-to-area ratio configuration. The heat losses, for wind velocity of 10 (m / s) and North direction, are, approximately, 120 % of C 1 , 131 % of C 1 , 143 % of C 1 , 165 % of C 1 and 174 % of C 1 , in Almeria, Rome, Budapest, Berlin and Helsinki, respectively. The longitudinal inclination of the receiver has positive effects on the performance of small scale linear Fresnel reflectors for urban applications. • An analysis of the wind effects, wind velocity and wind direction, on heat losses. • The effect of wind direction on heat losses is almost negligible. • The heat losses increase with the increase in longitudinal angle. • The longitudinal inclination of the receiver has positive effects. [ABSTRACT FROM AUTHOR]

The increased velocity (Invelox) wind turbine system is a novel wind energy collection device. This system can collect and accelerate the air flow through a funnel and a Venturi tube. However, the efficiency of this system is relatively low under some wind directions. To improve the aerodynamic performance of Invelox, a straight-through layout with a windshield was proposed. The flow field of the improved design was studied by applying Computational Fluid Dynamics (CFD) and was compared with that in the original configuration. Numerical results show that when the Invelox exit is facing the incoming wind, the ratio of the average velocity inside the Venturi tube to the incoming wind speed, i.e., the speed ratio, will drop sharply, and even the airflow will push back. The improved layout can eliminate the sensitivity of incoming wind direction to aerodynamic characteristics. The windshield can effectively reduce the interference of incoming air to the outlet air, making the speed ratio increase by about 42%. Different wind profiles in the atmospheric boundary layer are used in the boundary of the flow domain as the incoming flow wind. With the increase in the wind profile index, the speed ratio of the Invelox system will gradually decrease. [ABSTRACT FROM AUTHOR]

This paper analyses importance of including wind direction (WD) as an additional explanatory variable to the wind speed (WS) for evaluating uncertainty in wind turbine (WT) power output (Pout). Using available measurements of an actual WT, the paper compares a 'two‐dimensional' (2D) Pout ‐WS model with a 'three‐dimensional' (3D) Pout ‐WS‐WD model for two general cases: (a) for the specific input WS and WD values (i.e. WS and WD without uncertainties), and (b) for the forecasted input WS and WD values (i.e. WS and WD with uncertainties). In paper, 2D and 3D Gaussian mixture Copula model and vine Copula framework are combined with 2D and 3D Markov chain models, which are used to forecast input WS and WD data with uncertainties. The obtained results show that inclusion of WD will provide noticeable improvement for models with no uncertainties in input WS and WD data, while in the case of forecasted WS and WD data with uncertainties, WS is a much stronger contributor to the total WT Pout uncertainty than WD. [ABSTRACT FROM AUTHOR]

Abstract This study uses the Offset Elliptical Normal (OEN) mixture model to parameterize the seasonal–diurnal wind climate of Rome, Italy, for engineering design purposes, and also to reveal the physical meteorology of this “mixed” wind climate. The joint probability density function (PDF) of the wind vectors in the zonal–meridional plane are represented by a mixture of disjoint bivariate‐Normal ellipses. Each OEN ellipse is tentatively attributed to a physical wind mechanism: sea/land breezes; transient coastal jets; katabatic flows; the migrating atmospheric tide; and (non‐diurnal) geostrophic winds. The model enables a fuzzy probability of each wind mechanism to be assigned to each observation, allowing the progression of the various diurnal cycles to be tracked through time. This seasonal–diurnal parametric model is directly applicable to wind energy resource estimation, pollution studies, pedestrian comfort, and heating and ventilation design. The model is also an essential starting point in methods to simulate realistic time series of wind speed and direction.

This study addresses the problem of Dynamic Travelling Salesman Problem for a multi-agent system using a fleet of sailboats. A genetic algorithm (GA) is proposed, which attributes to each agent a varying number of targets to be collected. GA allows obtaining a suboptimal solution in the shortest time possible. Moreover, this study adapts it to the specific problem involving a fleet of sailboats, which is a challenging task with comparison to autonomous underwater vehicles or motorised vehicles in terms of the propulsion. Therein motors can be flexibly controlled while sailboat movements are constrained by available wind direction and speed. Thus the method takes into account wind conditions at various locations of the sailboat. Simulation results demonstrate the effectiveness of the proposed approach.

The Balbina reservoir (59°28'50'' W, 1°53'25'' S), located near the city of Manaus, AM in central Amazonia, is the second largest hydroelectric reservoir in the Amazon basin. Carbon dioxide concentration measurements were performed at high frequency (10 Hz) at this reservoir with an IRGA Model LiCOR 7500A and meteorological variables were measured with a floating platform with sensors 2 meters above the surface of the lake. Maximum and minimum CO2 concentrations were observed during the night, related to forest breeze enriched with CO2 and the respiration or photosynthetic activity of the lake. Due to the dimensions of the lake, both land and lake breezes control the concentration of CO2. CO2 showed a strong correlation with the meteorological variables, temperature (- 0.76) and relative humidity (0.71). However, only the wind direction showed a statistically significant effect at 5% in the cross-correlation. Our results corroborate other studies in this lake and other Amazonian reservoirs.

Traditionally, circular cross-section towers have been used as supporting systems of wind turbines, but weaknesses have become apparent with recent upsizing of wind turbines. Thus, polygonal cross-section towers have been proposed and used in Europe. In this study, the effects of polygonal cross-sections on the aeroelastic and aerodynamic characteristics of wind turbines were examined through a series of wind tunnel tests. Aeroelastic tests showed that a square cross-section tower showed instability vibrations, and polygonal cross-section towers showed limited vibrations for tower-only cases. However, for wind turbines with various polygonal cross-section towers, no instability vibrations were observed, and displacements increased proportionally to the square of mean wind speed. Furthermore, pressure measurements showed that local force coefficients changed largely depending on wind direction and azimuth angle. Local drag force coefficients decreased with increasing number of tower sides, approaching those of the tower-only case, and local lift force coefficients showed larger absolute values than those of the tower-only case. The maximum mean and fluctuating drag force and the maximum fluctuating lift coefficients at each height decreased with increasing number of tower sides.

In view of the difficulty of wind direction retrieval in the case of the large space and time span of the global sea surface, a method of sea surface wind direction retrieval using a support vector machine (SVM) is proposed. This paper uses the space-borne global navigation satellite systems reflected signal (GNSS-R) as the remote sensing signal source. Using the Cyclone Global Navigation Satellite System (CYGNSS) satellite data, this paper selects a variety of feature parameters according to the correlation between the features of the sea surface reflection signal and the wind direction, including the Delay Doppler Map (DDM), corresponding to the CYGNSS satellite parameters and geometric feature parameters. The Radial Basis Function (RBF) is selected, and parameter optimization is performed through cross-validation based on the grid search method. Finally, the SVM model of sea surface wind direction retrieval is established. The result shows that this method has a high retrieval classification accuracy using the dataset with wind speed greater than 10 m/s, and the root mean square error (RMSE) of the retrieval result is 26.70°.

Comprehensive bridge design should consider simultaneous actions of wind and temperature. The current load combination method of directly superposing extreme wind and temperature actions ignores the correlation between wind and temperature, resulting in too conservative bridge load estimates, and limiting the further development of the bridge span. Therefore, this paper proposes a method to determine the joint distribution of wind speed, wind direction, and air temperature actions on long-span bridges based on trivariate metaelliptical and Plackett copulas. First, the technique of establishing the trivariate joint distribution via trivariate metaelliptical and Plackett copulas is introduced. Next, the conditional joint distributions of wind speed and air temperature under the specific wind directions are derived from these. Using the concept of conditional bivariate Kendall return period (KRP) proposed in this paper, the conditional KRP isolines of wind speed and air temperature for specific wind directions are constructed. Then, conditional joint estimates of wind speed and air temperature actions for several specific wind directions are obtained using the following principle: the conditional bivariate design return period should be equal to the conditional univariate one. The method feasibility is verified by the case study of the Changtai Yangtze River Bridge in China, which is currently under construction and will be the largest cable-stayed bridge in the world. The results show that the joint actions of wind and temperature on the bridge greatly reduce as compared with the simple superposition of extreme wind and temperature actions specified in the design code. Moreover, a significant contribution of wind direction in the above joint distribution on the large-span bridge load is proved. [ABSTRACT FROM AUTHOR]

Parasitoids need to find their plant-feeding hosts in complex environments that contain multiple other plant and insect species. They usually rely on herbivore-induced plant volatiles to locate herbivore-infested plants from a distance and their foraging efficiency may be reduced when volatile information is not available. Downwind foraging during times when high wind speeds prevent odour-guided upwind flights may create foraging situations with limited accessibiliy to volatile information. We hypothesized that parasitoids forage less efficiently by landing on nonhost-damaged or undamaged plants when they are forced to fly downwind and tested this in a wind tunnel experiment. We released the parasitoid Cotesia glomerata (Hymenoptera, Braconidae) either upwind or downwind of a plant stand and observed their foraging behaviour. During downwind foraging, parasitoids were less successful in host finding and needed more time until they managed to oviposit in a host caterpillar compared to the upwind foraging situation. The observed increase in foraging time was caused by prolonged foraging on nonhost-infested and undamaged plants in the downwind situation, indicating that parasitoids leave an unprofitable patch that does not contain host caterpillars earlier, when they perceive volatiles from other herbivore-infested plants located upwind. Volatile information on the availability of herbivore-infested plants within a plant stand seems to be crucial for efficient foraging in plant stands that contain a mixture of host-infested, nonhost-infested and undamaged plants. Parasitoid foraging efficiency may thus be strongly reduced when high wind speed prevents odour-guided upwind flight. • Downwind-flying parasitoids foraged less efficiently than upwind-flying parasitoids. • Upwind-flying parasitoids had access to HIPVs from all herbivore-infested plants. • Low HIPV availability reduced between-plant movement of downwind-flying parasitoids. • Downwind-flying parasitoids foraged more intensively on nonhost-infested plants. • Intensive foraging on nonhost-infested plants delayed host finding. [ABSTRACT FROM AUTHOR]

The results of monitoring and examination of farmers in Barito Utara District by examining the cholinesterase enzyme by the Regional Health Laboratory and the District Health Office of Barito Utara in the blood of farmers found 71.19% experienced organopathic pesticide poisoning. This study aims to analyze the risk factors associated with the level of pesticide poisoning in rice farmers in Teweh Selatan Subdistrict, Barito Utara District, namely mixing dosage, spraying time, spraying frequency, spraying duration, working period, wind direction, and use of personal protective equipment. The research design used was observational with cross sectional approach. The number of samples is 55 people taken by simple random sampling. Rice farmers who experienced pesticide poisoning by 56.4%. Chi-Square Test showed four variables had a significant relationship with the incidence of pesticide poisoning and were a risk factor for the occurrence of pesticide poisoning namely mixing dose (p=0.003 OR=6.909; 95% CI=2.020-23.627), frequency of spraying (p=0.004; OR=6,300; 95% CI=1.913-20.749), working period (p=0.020; OR=4.416; 95% CI=1.402-13.906) and wind direction (p=0.007; OR=5.714; 95% CI=1.756-18.591). Multiple logistic regression test showed that the most dominant factor related to the incidence of pesticide poisoning was the frequency of spraying. Risk factors associated with the incidence of pesticide poisoning are mixing dosage, frequency of spraying, working period and wind direction. [ABSTRACT FROM AUTHOR]

The global warming, decline in wind speed and extreme rainfall have been documented to promote the expansion of bloom area. However, few studies focus on the effect of wind direction on bloom area. The monthly data between May and September from 2011 to 2018 were collected to analyze the relationship between environmental factors and bloom area. Pearson correlation analysis indicated that bloom area was negatively correlated with monthly proportion of consecutive unidirectional wind days (PCUWD) but positively correlated with chlorophyll a (Chl-a). During the whole studied period, wind speeds were lower than 3.1 m/s and Chl-a concentrations were higher than 20 μg/L in all months. In this case, the sufficient Microcystis biomass could aggregate into large-scale bloom area only by vertical floating. This could explain why no significant relationship between wind speed and bloom area was found in our study. Except for August, wind speed declined each month which promoted the increase of total phosphorus (TP) and Chl-a concentrations. The low value of PCUWD insufficiently transported cyanobacterial patches from other zones to accumulate with the existing cyanobacterial patches in the downwind area of the lake into dense and small-scale surface scum. In May and June, the decreased PCUWD was conducive to maintain a large-scale bloom area. [ABSTRACT FROM AUTHOR]

• Solar radiation, humidity & clouds are the dominant controls of solar park outputs. • PV outputs are ≤43% higher under southerly winds compared to northerly equivalents. • Wind speed has no effect on PV electricity output in low-wind environments. The urgent need to decarbonise energy supplies has prompted exponential growth of solar photovoltaic (PV) systems across the world. As the penetration of renewable energy sources increases, the need to accurately forecast electricity output heightens to ensure efficient energy system operation. While exposure to high temperatures and moisture are known to significantly reduce PV panel efficiency, the effects of wind on both PV panel temperature and electricity output are poorly resolved. Here, meteorological and PV panel production data from Westmill Solar Park, Oxfordshire, were examined to determine the influence of wind, cloud, ambient temperature and relative humidity. We found that, after solar radiation, relative humidity and cloud cover were the dominant controls of PV electricity output; increases in relative humidity and cloud cover were associated with decreased electricity outputs. However, when all other variables were held constant, the mean electricity generated under southerly winds was 20.4 – 42.9% greater than under northerly winds, with the difference greater at higher electricity outputs and attributable to differences in surface cooling capabilities caused by the PV array asymmetry. This finding suggests that PV electricity output predictions could be improved by incorporating wind direction into computer models. Moreover, there is potential to modify solar park design and deployment location to capitalise on wind benefits, especially in areas where panel temperatures are a leading cause of efficiency loss. Ensuring deployments are optimised for site environmental conditions could boost electricity outputs, and therefore profitability, with implications for system viability in post-subsidy markets. [ABSTRACT FROM AUTHOR]

Industrial activities are important sources of atmospheric pollution worldwide. The elemental content in lichens was measured and analyzed with respect to the dominant wind direction and distance from pollution sources. In direction of the dominant winds, the content of Fe decreased with distance from the pollution source, which was a steel works situated in the flat country. Otherwise, in direction of the dominant winds, the content of Mn increased depending on the circumferences of trees found at various distances from the pollution sources. Older trees represented valuable indicators of elemental bioaccumulation over time. It was confirmed that geomorphology of the studied areas, dominant wind direction and older trees played an important role in the elemental bioaccumulation in lichens along the spatial gradient. Therefore, epiphytic lichens are regarded as valuable indicators in monitoring of environmental pollution in the study area. [ABSTRACT FROM AUTHOR]

Compact high-frequency (HF) antenna arrays are convenient to deploy. However, using a small-aperture HF surface wave radar for wind direction measurement is still a challenging problem, since an unsatisfactory array pattern degrades the performance of Bragg ratio estimation. To address this issue, a digital beamforming method based on a superdirective synthesis technique for an HF receiving array that consists of seven elements positioned on a 5-m diameter circle is proposed. This superdirective beamforming method contains a sidelobe constraint. Subsequently, a hybrid superdirective beamforming and direction-finding method is adopted to estimate the wind direction using a multifrequency HF radar based on a circular array (MHF-C). The superdirective beamforming approach, as well as the wind direction estimation method, is presented in detail. The wind direction estimation method has been applied to the raw data sets that were collected with two MHF-C radars installed along the coast of the East China Sea in April 2015 and comparisons between radar-derived and in situ wind directions have been made. Ship-mounted anemometers were used to obtain in situ measurements at six sampling locations within the overlapping coverage of both radars. Another comparison between the radar-derived and anemometer-derived wind directions, which were obtained from June 15, 2015 to August 12, 2015, has also been made. The results indicate that the proposed method is effective for wind direction estimation with root-mean-square differences (RMSDs) between 24.1° and 33.1°, when wind speeds were higher than 5 m/s. The analysis encourages us to recommend a minimum wind speed of 5 m/s for reasonably assessing wind direction measurement performance. [ABSTRACT FROM AUTHOR]

The utilization of windbreaks is a globally prevailing management practice for agricultural production and restoration of degraded ecosystems by reducing wind-induced destruction. Examining how windbreaks affect leeward surface wind speed is critically important to quantify the efficiency of windbreaks. A semiempirical model for simulating horizontal distribution of wind speed leeward windbreaks was developed, combining wind tunnel experiments with prevailing literature. The model simulated the horizontal leeward wind speed distribution windbreaks with acceleration and deceleration terms; simultaneously considering four key impact factors (windbreak aerodynamic porosity, surface roughness, Richardson number and wind incident angle). It also comprises of a simple quantitative method for determining windbreak aerodynamic porosity from optical porosity. Model results compared with published data illustrate that the model is robust in various wind speed distributions under different windbreak structures and turbulence conditions. The simulation results indicate horizontal wind speed distribution is definitely dependent upon windbreak porosity. Wind speeds decline with increasing wind incident angle. Wind speeds decrease obviously with increasing Richardson number while decrease slightly with decreasing surface roughness, when the horizontal distance is between two and twenty times the windbreak height. Moreover, the escalating wind incident angle strengthens the weakening effects of windbreak porosity on wind speed, while reducing Richardson numbers expand the decreasing intervals of relative wind speed with increasing surface roughness. The model provides a simple and practical method to better assess the impacts of windbreaks, which can be incorporated in agricultural policy-making decisions to reduce the detrimental impacts of wind. [ABSTRACT FROM AUTHOR]

The data of atmospheric reanalysis NCEP/NCAR over 1948–2017 (R-1) and NCEP/DOE over 1979–2017 (R-2) have been used to show that variations of the Caspian Sea level are closely correlated with the long-term variations in the field of surface wind in the sea region caused by the transformation of atmospheric circulation over Eurasia. Winds of the eastern and northern rhumbs have been shown to play the main role in variations of evaporation over the Caspian Sea. In the periods of level drop in the Caspian Sea (1948–1976 and 1996–2017), eastern winds dominate, bringing dry and warm air from Central Asia and thus contributing to an increase in water evaporation from the Caspian Sea. In the periods of level rise in the Caspian Sea (1977–1995), northern winds dominate, which cause a decrease in the rate of evaporation. Calculations of evaporation over the Caspian Sea water area using reanalysis data R-1 and R-2 fully confirm these conclusions. A close correlation has been shown to exist between evaporation and the level of the Caspian Sea. The coefficients of correlation between the nonstandardized increments of evaporation and level in the Caspian Sea are –0.86 and –0.75 by R-1 and R-2, respectively. Moreover, the contribution of evaporation to the current drop in the Caspian Sea level by data of improved reanalysis R-2 is greater than that by R-1, because the inflow of air masses from the nearby dry region of the Central Asia according to R-2 has been greater in the recent decade. [ABSTRACT FROM AUTHOR]

Pesticide spray drift is potentially a significant source of exposure to off‐target, adjacent aquatic habitats. To estimate the magnitude of pesticide drift from aerial or ground applications, regulatory agencies in North America, Europe, and elsewhere rely on spray drift models to predict spray drift deposition for risk assessments. Refined assessments should ultimately depend on best‐available data for exposure modeling. However, when developing lower tier "screening" assessments designed to indicate whether further refinement is needed, regulators often make conservative assumptions with a resulting increased level of uncertainty in estimating environmental exposure or risk. In the United States, it is generally accepted that, to ensure conservative regulatory assessments, it is reasonable to assume that the wind speed might be 4.47 m/s (10 miles per hour [mph]), the relative humidity and temperature are highly conducive to drift, and the wind is blowing directly toward a receiving water for any given single spray event in a season. However, what is the probability these conditions will all co‐occur for each of 4 sequential spray events spaced a week apart (common practice for insecticides)? The refined approach in the present study investigates this question using hourly meteorological data sets for 5 United States Environmental Protection Agency (USEPA) standard crop scenarios to understand how real‐world data can reduce unnecessary uncertainty for sequential applications. The impact of wind speeds, temperatures, relative humidity, and wind direction at different times of day on annual drift loadings has been examined using a stepwise process for comparison with corresponding regulatory default loading estimates. The impacts on drift estimates were significant; interestingly, the time of day of the applications impacted variability more than did the selected crop scenario. When all these real‐world factors were considered, estimated 30‐y total drift loads ranged from 2% to 5% greater than the default estimate (2 of 30 cases due to high afternoon wind speeds) to 51% to 86% reductions (25 of 30 cases) with an overall average reduction of 63%. Integr Environ Assess Manag 2020;16:197–210. © 2019 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC) KEY POINTS: We show that readily available wind speed and direction, temperature, and relative humidity data are important for refining default simulated exposures for pesticides applied several times a season, because conservative default model inputs are unlikely to co‐occur on multiple application days.Using real‐world hourly meteorological data in place of default assumed input values produced estimated 30‐y drift loads ranging from 2% to 5% greater than default estimate (2 of 30 cases) to 51% to 86% reductions (25 of 30 cases) with overall average reductions of 63%.Existing drift models have tools that could account for some of these factors if they were approved for regulatory use, and in addition, other parameters such as type of aircraft, nozzle types, release heights, and swath widths probably also have impacts on default model estimates. [ABSTRACT FROM AUTHOR]

The thermohaline structure of water in the Antarctic coastal areas adjoining Molodezhnaya, Novolazarevskaya, and Bellingshausen stations is analyzed using many-hour soundings carried out in March–April 2019 during the 64th Russian Antarctic Expedition on the Akademik Fedorov research vessel. Water masses typical of the Antarctic zone (Antarctic surface, Antarctic shelf, Antarctic winter, upper circumpolar deep water, Bransfield Strait surface water) are identified, and the features of their temporal variability are described. It is shown that intradaily and interdaily variations in water temperature and salinity were observed during the measurement period. The changes in the water structure in the area of Molodezhnaya, Novolazarevskaya, and Bellingshausen stations occurred under changes in synoptic atmospheric conditions, and their frequency was close to that of tidal processes. [ABSTRACT FROM AUTHOR]

Under extreme weather conditions, the imprints of kilometer-scale marine atmospheric boundary layer roll vortices on the ocean surface are clearly visible in synthetic aperture radar (SAR) images of storms. Therefore, information about wind direction in storms can be obtained by analyzing SAR image features caused by boundary layer rolls. VH-polarized SAR imagery captures the structural features of storms well and shows prominent image gradients along the radial directions of the storm. The signal-to-noise ratios of VH-polarized images are small in low wind speed areas, but they are large in the same regions of VV-polarized images. Also, the capability of retrieving the atmospheric rolls orientation in VV-polarization is found to be sensitive to incidence angle, with better performances for larger incidence angles. Thus, there is the potential to retrieve the storm’s wind directions using a combination of the VH- and VV-polarized SAR observations. In this article, we use the local gradient method to estimate tropical cyclone (TC) wind directions from C-band RADARSAT-2 and Sentinel-1A dual-polarization (VV + VH) SAR imagery. As a case study, wind directions with a spatial resolution of 25 km are derived by using both wide-swath VV- and VH-polarized SAR imagery over two hurricanes (Earl and Bertha) and one Typhoon (Meranti). We compare wind directions derived from ten dual-polarization SAR images with collocated wind directions from buoys, Global Positioning System (GPS) dropsondes, scatterometer, and radiometer. Statistical comparisons show that the wind direction bias and root-mean-square error are, respectively, −0.54° and 14.78° for VV-polarization, 0.38° and 14.25° for VH-polarization, 0.20° and 13.30° for VV- and VH-polarization, suggesting dual-polarization SAR is more suitable for the estimation of TC wind directions than VV- or VH-polarization SAR. [ABSTRACT FROM AUTHOR]

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This study discusses the wind-induced response of existing pitch-controlled 1.25 MW wind turbine structures, with a particular focus on the influence of the blade-rotation effect, cross-wind loads of the tubular tower and the wind direction, and compares numerical responses with the measured dynamic responses. An integrated finite-element model consisting of blades, a nacelle, a tower and a foundation is established. The aerodynamic loads exerted on the rotating blades and the aerodynamic loads acting on the tubular tower are then obtained. A wind-induced response calculation method of the wind turbine structures corresponding to different wind speeds and wind directions is established for performing a wind-induced response analysis. Finally, comparisons between the measured responses and the corresponding numerical response results are performed to verify the accuracy of the proposed wind-induced response calculation method. The results indicate that neglecting the cross-wind aerodynamic loads of large-scale wind turbine structures can lead to unsafe design. The wind direction has different influences on the along-wind and cross-wind dynamic responses. The statistical values of the measured dynamic responses are slightly greater than those of the numerical analysis results, but the magnitudes of the responses are the same. Therefore, the proposed wind-induced response calculation method for wind turbine structures is feasible and reasonable. It can be used to conduct the fatigue life prediction of wind turbine tubular towers in future research which is an important issue in the structural design of wind turbine tubular tower structures. [ABSTRACT FROM AUTHOR]

The windsock is a meteorological instrument that indicates wind direction. This instrument is critical in sea travel and aviation and this sensor can prevent accidents in emergency situations such as storms caused by a particular wind direction.hus, in this work it is proposed to develop an electronic windsock using a rotary encoder module and infrared LEDS. For the development of the Wind Direction Sensor project an Arduino microcontroller and c ++ language were used. The engineered hybrid system converts the rotations into an electrical signal. These signals were associated with east, west, north and south orientations. The projected sensor presented a lower probability of error in the wind direction information when compared to the windsock that employs 5mm Infrared LED. [ABSTRACT FROM AUTHOR]

This study uses the Offset Elliptical Normal (OEN) mixture model to parameterize the seasonal–diurnal wind climate of Rome, Italy, for engineering design purposes, and also to reveal the physical meteorology of this "mixed" wind climate. The joint probability density function (PDF) of the wind vectors in the zonal–meridional plane are represented by a mixture of disjoint bivariate‐Normal ellipses. Each OEN ellipse is tentatively attributed to a physical wind mechanism: sea/land breezes; transient coastal jets; katabatic flows; the migrating atmospheric tide; and (non‐diurnal) geostrophic winds. The model enables a fuzzy probability of each wind mechanism to be assigned to each observation, allowing the progression of the various diurnal cycles to be tracked through time. This seasonal–diurnal parametric model is directly applicable to wind energy resource estimation, pollution studies, pedestrian comfort, and heating and ventilation design. The model is also an essential starting point in methods to simulate realistic time series of wind speed and direction. [ABSTRACT FROM AUTHOR]

For utilizing the high-quality wind energy around the high-rise building, the aerodynamic performance of building augmented straight-bladed vertical axis wind turbine (BASB-VAWT) was investigated by 2-dimensional CFD. The effects of wind direction, solidity, airfoil, and building configurations on BASB-VAWTs were studied to provide the reference of practical application. By considering the boundary layer effect of the building, the numerical results show that the aerodynamic performance of BASB-VAWTs is significantly sensitive to the wind direction. When the wind direction is North (the channel direction of BASB-VAWT is West), BASB-VAWTs barely generate power. The different airfoils, various solidity, and architectural configurations also have a great influence on the aerodynamic performance of BASB-VAWTs. With the increasing solidity, the load fluctuation can be reduced sharply and the maximum power coefficient is increased firstly and then decrease. Therefore, the optimal blade of NACA 0021 airfoil and solidity of 0.333 is promising to achieve better performance. Most of the building configurations were determined initially and thus the results in this paper merely provide a suggestion of the optimal building configuration. [ABSTRACT FROM AUTHOR]

Morocco has pursued an ambitious policy aimed at boosting renewable energies in the country. On this basis, we have examined the possibility of using wind turbines to generate electricity in Lamhiriz village in the south of Morocco, known for its strong winds. The wind speeds were statistically studied using the data recorded over one-year period collected from the mast which contains a set of measuring instruments at different altitudes. Based on several studies, we selected Weibull distribution to model the wind speeds, and we used the empirical method to estimate the scale and the shape parameters. Thereafter, a detailed analysis of seasonal and annual wind direction was presented. From the obtained results, the available energy density in this area is assessed by using WAsP software. Then, six commercial wind turbines of various sizes between 300 and 1300 kW were technically evaluated for electricity generation in Lamhiriz village by calculating their capacity factors and annual energy outputs. The results showed that the site under study is an adequate location for any of the adopted wind turbine models, where the annual energy output ranges from 1.44 to 6.75 GW h. Therefore, we can conclude that Lamhiriz have an attractive economical potential for developing large wind turbine farms. [ABSTRACT FROM AUTHOR]

This study proposes a simple approach based on Weibull distribution parameters for downscaling climatic wind speed and direction. In this method, the Weibull parameters of a Global Climate Model (GCM) are modified using Weibull parameters of the reference data (ECMWF). To correct the wind direction, the downscaling technique was applied to the eastward and northward wind components. All the wind components were simply transformed to positive values in order to fit a Weibull distribution. The unbiased wind speed was calculated by integrating the corrected wind components. Moreover, other models were considered to directly modify the wind speed (not wind components) using the same methodology. Performance and ability of the proposed approach were evaluated against the existing statistical downscaling techniques such as Multiplicative Shift Method (MSM), quantile mapping and support vector regression. In the models, the 6-h GCM wind component/speed was the sole predictor and the ECMWF reanalysis wind data was considered as the predictand. It is demonstrated that direct application of the proposed method on the wind speed slightly gives better estimation of the predictand rather than its application on wind components. The results indicate the Weibull distribution based method outperforms the other techniques for wind direction and magnitude. The method provides sound predictions for a wide range of wind speed from low to high values. By using the proposed downscaling technique for wind components, wind direction can be adjusted accordingly. [ABSTRACT FROM AUTHOR]

The dynamic velocity characteristics of wind have been studied over the past several decades. However, there was a lack of consideration for the incoming flow directions. Besides, the comfort assessment studies mainly focused on thermal comfort from the mechanism of heat transfer instead of wind comfort from the mechanism of tactile stimuli. This study carried out a mixed indoor and outdoor experiment. The indoor experiment was conducted with a room temperature of 29 °C and a relative humidity of 50%, which closely resembled the outdoor environmental conditions. Totally 17 healthy subjects dressed at 0.36 clo and being sedentary were exposed to five kinds of airflow during the experiment. According to the results, outdoor true natural wind was more preferred than directly supplied wind. This paper also proposed a novel wind comfort (WC) model by considering various air parameters. The model relied on tactile stimuli, which were the reflections of wind pressure fluctuations and could be affected by changes in velocity and direction of airflows. Based on these two dynamic characteristics, four wind perceptions, including wind intensity vote (WIV), velocity variation sense (VVS), direction variation sense (DVS) and overall enveloping sense (OES) were introduced and linearly regressed. The findings revealed that not only velocity but also the direction could affect the wind comfort evaluation. This paper will hopefully provide a better understanding of impacts of incoming flow directions on comfort and further rethink a novel route of dynamic wind environment imitation for future indoor environments. • We propose a wind comfort evaluation method that focuses on tactile stimuli. • Both velocity and incoming flow direction impact the wind comfort evaluation. • Four subjective perceptions included in wind comfort are newly introduced. • Simulated natural wind only copies the velocity feature of true natural wind. • Oscillating wind has better cooling effect but worse comfort than directly supplied wind. [ABSTRACT FROM AUTHOR]