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Showing papers on "Sea breeze published in 1998"


Journal ArticleDOI
TL;DR: In this paper, a method for selecting sea breeze days in an archipelago was developed with special application to the West Coast of Sweden, where the primary criterion for identifying a sea breeze was the occurrence of a distinct change in surface wind direction within a 24-hour period.
Abstract: A method for selecting sea breeze days in an archipelago was developed with special application to the West Coast of Sweden. The primary criterion for identifying a sea breeze was the occurrence of a distinct change in surface wind direction within a 24 h period. The data used in the study were gathered using hourly meteorological records from field stations situated on the West Coast. Six different filters were included in the method; each of them developed from empirical knowledge of the physical processes responsible for the occurrence of a sea breeze system. Using this method it is possible to create a data set of sea breeze days, which does not use distance to the shoreline as a necessary condition for classification. © 1998 Royal Meteorological Society.

104 citations


Journal ArticleDOI
TL;DR: The MEDCAPHOT-TRACE experiment as discussed by the authors studied the chemical and meteorological evolution of ozone and related trace gases (over land and sea), modulated by the various synoptic and local meteorological conditions (sea/land breeze circulation, local winds, inversion layers, etc.) in one of the largest urban agglomerations in the Mediterranean region.

101 citations


Journal ArticleDOI
TL;DR: In this article, the authors studied the role of the lake in terms of formation of a stable internal boundary layer due to advection of warm air from land with small CO2 concentration over the cooler lake surface.
Abstract: Nocturnal land breezes and daytime lake breezes are studied using data collected by the Canadian Twin Otter aircraft and a deck boat which traversed Candle Lake during the Boreal Ecosystem-Atmosphere Study (BOREAS). The nocturnal vertical transport of CO2, water vapor, and ozone over the lake consists of two parts: (1) mesoscale rising motion associated with land breeze convergence and (2) significant turbulence and vertical mixing driven by buoyancy in the lower part of the internal boundary layer and shear generation in the top part of the internal boundary layer. For comparison, the role of the lake in the daytime is examined in terms of formation of a stable internal boundary layer due to advection of warm air from land with small CO2 concentration over the cooler lake surface. Analysis of the aircraft and boat data indicates that the nocturnal land breeze plays an important role in the regional CO2 budget in the lake region. In the present study, CO2 is advected horizontally by a nocturnal land breeze circulation and vented vertically over Candle Lake (“chimney effect”). Such near-surface horizontal transport implies that part of the respirated CO2 never reaches the tower observational level, particularly under light wind conditions. This study speculates that preferred locations of vertical venting of CO2 may also occur due to convergence of nocturnal drainage circulations or flow meandering, although probably weaker than that associated with the land breeze. These circulations partly explain recent findings that tower-measured nocturnal turbulent fluxes of CO2 above the canopy and the subcanopy storage of CO2 frequently sum to less than the total respiration of CO2, leading to “missing CO2.” Unfortunately, the present study does not allow evaluation of all of the terms in the carbon dioxide budget.

99 citations


Journal ArticleDOI
TL;DR: Jaffe et al. as discussed by the authors investigated the role of suspended sediment in shore-normal beach profile changes and found that sediment resuspension typically occurred during isolated high-wave events associated with the passage of wave groups.

95 citations


Journal ArticleDOI
TL;DR: In this article, the authors classified wind storms according to their climatological and synoptic characteristics, indicating that the dominant synoptics situation is the Red-Sea trough and the warm advections.
Abstract: Continental wind storms are common along the Mediterranean coast. Along the northern coast they are mostly cold, similar to the Bora or the Mistral, and along the southern coast they are mostly warm, e.g., the Ghibli or the Shirocco. At the eastern Mediterranean basin and the Levant region, these storms are intermittently warm and cold during the same season and often even during the same event. Quasi-stationary systems, as well as moving disturbances, are the cause of such wind storms. Accordingly, the resulting weather conditions may be extremely converse due to the characteristics of the advected airmass. Specific regions in Israel, sensitive to easterly storms, are influenced by these wind storms for about 10% of the year (e.g., the westerly slopes of the mountains and valleys with west-east orientation). The frequency, however, of widespread storms covering the entire region is only approximately 1.4% of the entire year. These wind storms are therefore classified in the present study according to their climatological and synoptic characteristics; indicating that the dominant synoptic situation is the Red-Sea trough and the warm advections. These storms appear only from October-May and are most frequent during the cold season. The diurnal course is characterized by a strengthening in the morning hours and a weakening at noon and in the afternoon hours, due to the opposing effect of the westerly sea breeze, suppressing the easterly winds and the effect of katabatic winds. Nevertheless, synoptic conditions may contribute to this tendency as well. Accordingly, a significant increase in the frequencies of easterly storms, in relation to distance from the seashore has been identified. Although most of the stormy days are with westerly winds, the easterly wind storms has vast environmental implications, creating damage especially to agriculture and occasionally also to property and life; coastal flooding, potential air pollution, intensifying of forest fires and occasionally dust and sand storms.

88 citations


Journal ArticleDOI
TL;DR: The North American Research Strategy for Tropospheric Ozone-Northeast field measurements taken during 12-16 July 1995 indicate that ground-level ozone concentrations have exceeded the National Ambient Air Quality Standard level of 0.12 ppm for hourly ozone throughout the ozone transport region in the northeastern United States.
Abstract: The North American Research Strategy for Tropospheric Ozone-Northeast field measurements taken during 12–16 July 1995 indicate that ground-level ozone concentrations have exceeded the National Ambient Air Quality Standard level of 0.12 ppm for hourly ozone throughout the ozone transport region in the northeastern United States. Analyses of the meteorological conditions conducive to the ozone formation and accumulation reveal that the above ozone exceedances in the Northeast are associated with such meteorological features as the stagnant high pressure system, the Appalachian leeside trough, the frontal trough, the sea breeze, the channeling effects induced by the topography, and the stratified boundary layers. Also, aircraft measurements provide evidence for the buildup of ozone levels in the nighttime residual layer under southwesterly flows from 12 to 15 July. In this paper, it is shown that high ozone trapped aloft mixes downward, elevating the ground-level ozone concentrations as the daytime ...

72 citations


Journal ArticleDOI
TL;DR: Ganor et al. as mentioned in this paper collected 6170 samples from a ship in Haifa Bay and Tel Aviv, Israel, during the summer time and classified them according to their chemical composition, size, number of particles per cubic centimeter and morphology.

72 citations


Journal ArticleDOI
TL;DR: In this paper, the air quality aspects within the first 1500 m of the Atmospheric Boundary Layer over Athens are also discussed, and the profiles of ozone and nitrogen dioxide on sea-breeze and non-sea-reeze days with possible explanations.

71 citations


Journal ArticleDOI
TL;DR: In this article, the complex structure of the sea breezes developing in the Greater Athens Area (GAA) during a day with weak large-scale ambient winds is examined using consolidated field data and results from numerical model simulations.

69 citations


Journal ArticleDOI
TL;DR: In this paper, a research aircraft instrumented for meteorological and air chemistry measurements, and ground-based air-pollution-monitoring stations was used to study transport and distribution of primary and secondary air pollutants in Athens, Greece.

62 citations


Journal ArticleDOI
TL;DR: In this paper, the authors identify and establish the day-by-day relationship between mesoscale circulation and the air quality status over the metropolitan area of Athens for a period of 13 years and further investigate its temporal and spatial variability.

Journal ArticleDOI
TL;DR: In this article, the effect of coastal upwelling on sea-breeze circulation in Cabo Frio (Brazil) and the feedback of sea breeze on the up-welling signal in this region are investigated.
Abstract: . The effect of coastal upwelling on sea-breeze circulation in Cabo Frio (Brazil) and the feedback of sea-breeze on the upwelling signal in this region are investigated. In order to study the effect of coastal upwelling on sea-breeze a non-linear, three-dimensional, primitive equation atmospheric model is employed. The model considers only dry air and employs boundary layer formulation. The surface temperature is determined by a forcing function applied to the Earth's surface. In order to investigate the seasonal variations of the circulation, numerical experiments considering three-month means are conducted: January-February-March (JFM), April-May-June (AMJ), July-August-September (JAS) and October-November-December (OND). The model results show that the sea-breeze is most intense near the coast at all the seasons. The sea-breeze is stronger in OND and JFM, when the upwelling occurs, and weaker in AMJ and JAS, when there is no upwelling. Numerical simulations also show that when the upwelling occurs the sea-breeze develops and attains maximum intensity earlier than when it does not occur. Observations show a similar behavior. In order to verify the effect of the sea-breeze surface wind on the upwelling, a two-layer finite element ocean model is also implemented. The results of simulations using this model, forced by the wind generated in the sea-breeze model, show that the sea-breeze effectively enhances the upwelling signal. Key words. Meteorology and atmospheric dynamics (mesoscale meteorology; ocean-atmosphere interactions) · Oceanography (numerical modeling)

Journal ArticleDOI
TL;DR: In this article, an analysis of wind field and atmospheric turbulence in Athens, Greece covering a typical late-summer period with prevailing northerly wind is presented, showing a distinct difference between the northern and southern parts of the urban area.

Journal ArticleDOI
TL;DR: In this paper, the influence of both urbanization in modified land use in a plain area, the Nohbi plain of central Japan, and surrounding large-scale topography, such as the Japanese Alps, on the temperature and local wind over the plain has been investigated utilizing numerical simulations with a mesoscale meteorological model that uses the k−e model for turbulence.
Abstract: Influence of both urbanization in modified land use in a plain area, the Nohbi Plain of central Japan, and surrounding large-scale topography, such as the Japanese Alps, on the temperature and local wind over the plain has been investigated utilizing numerical simulations with a mesoscale meteorological model that uses the k−e model for turbulence. Obtained results are as follows. 1) Relative importance of natural topography and human-modified land use in various spatial scales has been clarified in the formation of characteristic diurnal patterns of sea breeze and temperature in the plain area. The Japanese Alps, which are the largest topographic feature in central Japan and are located far from the Nohbi Plain, around 100–200 km away, gave the most important influence on the wind over the plain area. The effect of the high mountains on the wind was caused by heating of the air mass over the plain due to weak subsidence associated with the return flow of the plain–plateau circulation. The urbani...

Journal Article
TL;DR: In this paper, the authors studied the effect of wind-generated, short-period wind waves to the background swell on the cusp morphology of a beach in southwestern Australia and found that the increase in wave height, a decrease in wave period and an intensification of the nearshore currents induced a diurnal cycle of beach change, and that the morphology became increasingly subdued due to accretion in the embayment and erosion of the horns.
Abstract: Beach morphology and nearshore hydrodynamics were monitored over a number of sea breeze cycles on a beach with pronounced beach cusp morphology in southwestern Australia. The action of the sea breeze resulted in consistent changes to the incident wave field and beach cusp morphology, and induced a diurnal cycle of beach change. The morphological changes were accomplished without an apparent sediment gain or loss, but involved a redistribution of sediment within the cusp morphological system. During the sea breeze, the addition of locally-generated, short-period wind waves to the background swell resulted in an increase in wave height, a decrease in wave period and an intensification of the nearshore currents. The cusp morphology became increasingly subdued due to accretion in the embayment and, to a lesser extent, erosion of the horns. After the cessation of the sea breeze, the wind-wave energy level gradually decreased and the associated wind-wave period increased. Accretion on the cusp horns was accompanied by minor erosion of the embayment and resulted in an accentuation of the cusp morphology. The build-up of the cusp morphology was a consequence of the morphodynamic feedback between the antecedent cusp morphology and the wave runup characteristics. The wave runup was diverted from the horn into the embayment, resulting in decreased backwash volumes and hence build-up of the horn. In the cusp embayment, increased backwash volumes resulted in scouring and the suppression of potential swash events at the base of the beachface. Consequently, the proportion of infragravity-wave energy in the runup record was larger in the embayment than on the horn. Ten hours after the sea breeze had stopped blowing, significant amounts of wind-wave energy were still present. It is suggested that these wind waves were generated a distance of almost 200 km south of the study area, implying that the presence of the local sea breeze may have regional implications for coastal processes.

Journal ArticleDOI
TL;DR: In this paper, the authors recognized the sea surface signature of a coastal lee wave using ERS-1 synthetic aperture radar (SAR) images of the west side of the Taiwan Strait taken on December 8, 1994.
Abstract: Alternative dark-bright patterns on ERS-1 synthetic aperture radar (SAR) images of the west side of the Taiwan Strait taken on December 8, 1994, were recognized to be the sea surface signature of a coastal lee wave. Such waves are called coastal lee waves because they occur along the lee side of the coast. The coastal lee waves appeared in the form of a wave packet distributed within an offshore band 20–40 km wide. The first packet, which occurred in the northern portion of the observed area, contained six waves with variable wavelengths (defined as the spatial separation between two waves) from 1.7 to 2.7 km. The second packet, in the middle, contained 10 waves with a relatively uniform wavelength of 4.2 km. The third packet, in the southern portion, contained 17 waves with an average wavelength of 2.0 km. The crest lengths were from 20 to 80 km. Local meteorologic parameters observed simultaneously at Fuzhou, China, close to the imaged area, showed an offshore wind of 1.5–3.5 m/s and a land surface air temperature of 19°C, which was 4°C lower than the sea surface temperature (SST). Thus the lower atmospheric boundary conditions at imaging time were very favorable both for generating the land breeze circulation and small wind waves on the sea surface, which are in the Bragg-scattering wavelength band of the C band ERS-1 SAR. A physical model of a three-layer atmosphere was developed in order to explain how the land breeze circulation can generate the coastal lee waves. The results showed that the vertical velocity disturbance caused by the wind convergence at the land breeze frontal zone is of vital importance for the generation of coastal lee waves, and the model gave very good estimates of the processes observed. The SAR imaging mechanisms of the waves were analyzed in detail. The differences between coastal lee waves and ocean internal waves, which appear as similar alternative dark-bright patterns on SAR images, were also discussed.

Journal ArticleDOI
TL;DR: In this paper, the authors used a three-dimensional hydrostatic model to simulate the propagation speed of a sea breeze circulation cell in a terrain-following coordinate system, which includes a third-order semi-Lagrangian advection scheme.
Abstract: The inland and offshore propagation speeds of a sea breeze circulation cell are simulated using a three-dimensional hydrostatic model within a terrain-following coordinate system. The model includes a third-order semi-Lagrangian advection scheme, which compares well in a one-dimensional stand-alone test with the more complex Bott and Smolarkiewicz advection schemes. Two turbulence schemes are available: a local scheme by Louis (1979) and a modified non-local scheme based on Zhang and Anthes (1982). Both compare well with higher-order closure schemes using the Wangara data set for Day 33–34 (Clark et al., 1971). Two-dimensional cross-sections derived from airborne sea breeze measurements (Finkele et al. 1995) constitute the basis for comparison with two-dimensional numerical model results. The offshore sea breeze propagation speed is defined as the speed at which the seaward extent of the sea breeze grows offshore. On a study day, the offshore sea breeze propagation speed, from both measurements and model, is -3.4 m s-1. The measured inland propagation speed of the sea breeze decreased somewhat during the day. The model results show a fairly uniform inland propagation speed of 1.6 m s-1 which corresponds to the average measured value. The offshore sea breeze propagation speed is about twice the inland propagation speed for this particular case study, from both the model and measurements. The influence of the offshore geostrophic wind on the sea breeze evolution, offshore extent and inland penetration are investigated. For moderate offshore geostrophic winds (-5.0 m s-1), the offshore and inland propagation speeds are non-uniform. The offshore extent in moderate geostrophic wind conditions is similar to the offshore extent in light wind conditions (-2.5 m s-1). The inland extent is greater in light offshore geostrophic winds than in moderate ones. This suggests that the offshore extent of the sea breeze is less sensitive to the offshore geostrophic wind than its inland extent. However, these results hold only if it is possible to define an inland propagation speed. For stronger offshore geostrophic winds (-7.5 m s-1), the sea breeze is completely offshore and the inland propagation speed is ill-defined.

Journal ArticleDOI
TL;DR: In this article, the association of air pollution with sea breeze circulation in the Greater Athens Area (GAA) is discussed on the basis of the behaviour of ozone and peroxyacetyl nitrate (PAN).

Journal ArticleDOI
TL;DR: In this paper, surface stations were operated and radiosonde ascents were performed to analyze the characteristic features of the land-sea-breeze circulation in Cubatao, a city situated 15 km inland at a steep slope.
Abstract: The area between the Atlantic Ocean and Sao Paulo is highly polluted due to high emission rates at Cubatao, a city situated 15 km inland at a steep slope. It was expected that secondary circulations would develop caused by the land–sea contrast and strong orographic changes, which influence the transport and diffusion of air pollutants. In 1994–95, surface stations were operated and radiosonde ascents were performed to analyze the characteristic features of the land–sea-breeze circulation. The stations make evident a land–sea-breeze system that arrived in the suburbs of Sao Paulo in the early afternoon. The upslope winds favor the propagation of the sea breeze at the steep slope. During the measurement period, large-scale northwesterly winds prevailed that advected warm air from the plateau to the coastal area in the afternoon and resulted in a limitation of the boundary layer growth. The data were used to initialize a three-dimensional mesoscale model for calculation of the transport and deposit...

Journal ArticleDOI
TL;DR: In this paper, the authors analyzed the wind regime in the Greater Athens Area (GAA) during a day when the sea breeze was opposing a moderately strong synoptic-scale flow.

Journal ArticleDOI
TL;DR: This paper examined thermally induced flows (or "snow breezes" associated with snow cover in the boreal forests of Canada and found that a characteristic snow breeze signature is clearly evident in wind observations averaged over 27 days of data, in agreement with model simulations.
Abstract: This study examines thermally induced flows (or “snow breezes”) associated with snow cover in the boreal forests of Canada. Observations from a lake less than 4 km across were made as part of the Boreal Ecosystem-Atmosphere Study (BOREAS) winter field campaign. These are interpreted with the aid of idealized three-dimensional mesoscale model simulations representing the forest-lake contrast. Typically, strong forest-lake temperature contrasts develop in the lowest 50 m of the atmosphere during the morning. The resulting pressure gradients induce low-level onshore wind components across the lake. This snow breeze persists into the afternoon provided that large-scale winds remain light. A characteristic snow breeze signature is clearly evident in wind observations averaged over 27 days of data, in agreement with model simulations. The study suggests that snow breezes will regularly develop over the many larger lakes and other unvegetated areas in the region.

Journal ArticleDOI
TL;DR: In this paper, the influence of the main large-scale wind directions on thermally driven mesoscale circulations at the Baltic southwest coast, southeast of Sweden, is examined.
Abstract: The influence of the main large-scale wind directions on thermally driven mesoscale circulations at the Baltic southwest coast, southeast of Sweden, is examined. The aim of the study is to highlight small-scale alterations in the coastal atmospheric boundary layer. A numerical three-dimensional mesoscale model is used in this study, which is focused on an overall behaviour of the coastal jets, drainage flows, sea breezes, and a low-level eddy-type flow in particular. It is shown that synoptic conditions, together with the moderate terrain of the southeast of Sweden (max. height h0 ≤ 206 m), governs the coastal mesoscale dynamics triggered by the land-sea temperature difference Δ T. The subtle nature of coastal low-level jets and sea breezes is revealed; their patterns are dictated by the interplay between synoptic airflow, coastline orientation, and Δ T.

Journal ArticleDOI
TL;DR: In this paper, the authors study the observations of two meteorological stations on the North Sea coast: Hoek van Holland (HVH) and IJmuiden (IJM) and find that diurnal variations are very similar in autumn and winter, but differ in spring and summer.

Journal ArticleDOI
TL;DR: In this article, the distribution of lightning across the Florida panhandle and adjacent coastal waters and its relationship to the prevailing low-level flow was examined using cloud-to-ground lightning data.
Abstract: Six years (1989–94) of cloud-to-ground lightning data are used to examine the distribution of lightning across the Florida panhandle and adjacent coastal waters and its relationship to the prevailing low-level flow. Only warm season data between 1 May and 31 October are used. The prevailing flow is determined by subdividing the low-level (1000–700 mb) vector mean wind into categories that are either parallel or perpendicular to various parts of the coastline. Moderate wind speeds (2–5 m s−1) generally are found to be more conducive to producing lightning than stronger speeds. Wind speeds stronger than 5 m s−1 likely inhibit the formation of the sea breeze, the main focus for summertime thunderstorms in the region. Onshore, offshore, and parallel flows are found to play important roles in determining the patterns of flash locations in each flow regime. The complexity of the coastline also is found to have a major impact on the flash distributions. The prevailing wind direction is shown to be relat...

Journal ArticleDOI
TL;DR: In this paper, the results of a lidar study of sea-breeze behavior near Akhtopol in the southeastern corner of Bulgaria are described, where vertical cross-sections at different azimuths through the nearshore atmosphere are presented.
Abstract: This paper describes results of a lidar study of sea-breeze behavior near Akhtopol in the southeastern corner of Bulgaria. The lidar site was a few hundred meters from the western shore of the Black Sea. Analyses are presented of vertical cross sections at different azimuths through the nearshore atmosphere. Three different stages of the sea–land-breeze circulation are discussed: the offshore land-breeze flow, the near-calm period before the onset of a sea breeze, and an onshore sea-breeze flow. The differences in backscatter between the moist, droplet-laden air over the water and the drier air over land with its smaller particles have allowed the characteristic features of the circulations to be identified. Comparisons to simultaneous pilot balloon and surface meteorological observations have supported the interpretations.

Journal ArticleDOI
TL;DR: In this article, the initiation and location of summer season convective activity, occurring between 1500 and 1800 UTC within a 100-km radius of the Mobile, Alabama, National Weather Service WSR-88D radar site, was examined on days when weak vertical wind shear environments existed.
Abstract: The initiation and location of summer season convective activity, occurring between 1500 and 1800 UTC within a 100-km radius of the Mobile, Alabama, National Weather Service WSR-88D radar site, was examined on days when weak vertical wind shear environments existed. Data were collected during June and July of 1996 based on 1200 UTC analyses of upper-air charts, radar, and GOES-8 satellite imagery. Thirteen case days were selected for detailed analysis. The precise location of initiation was found to be a function of both the 0‐1-km base-state flow and the extent of the flow’s interaction with physiographic features and local sea- and bay-breeze circulations. The modified mean 1800 UTC sounding for case days was characterized by a well-mixed boundary layer, a deep moistadiabatic lapse rate, and an overall decrease in relative humidity with height. For all case days, the surface parcel was found to be the most unstable air parcel within the mixed layer. A distinct bimodal distribution was found to exist in the 0‐1-km base-state wind flow pattern with flow predominantly east-southeast or westsouthwest. Thunderstorms were observed to initiate in a ‘‘mirror image’’ pattern on either side of Mobile Bay and were focused near elevation peaks, along the sea breeze, and at or near the orthogonal intersection of the sea- and bay-breeze circulations on either side of the bay.

Journal Article
TL;DR: In this article, a three-dimensional meso-scale NWP model, the Arpege / Aladin model, has been used to examine the characteristics of the sea breeze circulations over an area with an irregular coastline and complex surface-heating patterns on the Romanian Black Seaside.
Abstract: A three-dimensional meso-scale NWP model, the Arpege / Aladin model, has been used to examine the characteristics of the sea breeze circulations over an area with an irregular coastline and complex surface-heating patterns on the Romanian Black Seaside. The upslope wind on the Carpathian-Balkanian mountain slopes has also been studied. Given the importance of physical parameterization in the simulation of such phenomena, a comprehensive description of the physical package of Arpege / Aladin is first presented. The results of the simulations compare reasonably well with data available from surface Romanian stations, radar and satellite pictures. Experiments with ideal data have also been performed and essential surface features for these circulations were identified. The results show that the Arpege / Aladin model is well equipped for the description of such phenomena without any specific tuning. Concerning the sea breeze on the Romanian Seaside, the real experiments have shown that severe weather events can happen along the breeze front. This is, in fact, the cumulated effect of the breeze front and the afternoon convection over the coastal zone with reduced vegetation cover.

Journal ArticleDOI
TL;DR: In this article, a group of parallel cloud lines was identified in seven successive space shuttle photographs taken over the Pakistani offshore zone in the northern Arabian Sea on April 29, 1993, and the lines are generated by an atmospheric solitary wave packet characterized by decreases in amplitudes and wavelengths from the front to the rear.
Abstract: A group of parallel cloud lines was identified in seven successive space shuttle photographs taken over the Pakistani offshore zone in the northern Arabian Sea on April 29, 1993. There are a total of 19 lines aligned with the length of the leading line longer than 250 km and an average separation distance (wavelength) of 1 km. We suggest that the lines are generated by an atmospheric solitary wave packet characterized by decreases in amplitudes and wavelengths from the front to the rear. These features are comparable with the dnoidal soliton solution to the Korteweg-de Vries (KdV) equation. The land breeze and katabatic flow are proposed as a possible generation mechanism.

Journal ArticleDOI
TL;DR: In this article, the influence of vegetation and environmental conditions on the lake breeze and associated boundary-layer turbulence structure has been studied using a two-dimensional nonhydrostatic, compressible mesoscale model coupled with the SiB2 land-surface scheme.
Abstract: The influence of vegetation and environmental conditions on the lake breeze and associated boundary-layer turbulence structure has been studied using a two-dimensional nonhydrostatic, compressible mesoscale model coupled with the SiB2 land-surface scheme. The results show that the impacts of vegetation on the lake effects are dependent on the environmental conditions, such as soil wetness and background wind, as well as vegetation characteristics. Both soil wetness and background wind play important roles in modifying lake effects on boundary-layer turbulence and the lake breeze, while the effects of vegetation type are secondary compared to the other factors. Without background wind, and under the same soil wetness, the maximum horizontal windspeed of the lake breeze is insensitive to the type of vegetation. Soil wetness can greatly affect both the maximum horizontal windspeed and the maximum vertical velocities of the lake breeze. With background wind, the lake-breeze circulations, upward motion regions, and boundary-layer turbulence structure all change markedly. A weaker background wind can strengthen the lake breeze, while stronger background wind suppresses the lake breeze circulations. The distribution of sensible and latent heat fluxes is also very sensitive to the soil wetness and background wind. However, for the same soil wetness (0.25 and 0.4 were chosen), there is only a small difference in the distribution of sensible and latent heat fluxes between the bare soil and vegetated soil or between the types of vegetated soils.

Journal ArticleDOI
TL;DR: In this article, the authors studied the wind speed dependence of aerosol scattering coefficient in the atmospheric boundary layer at a tropical coastal station, using the data obtained from a bistatic continuous wave lidar.