Sea breeze

About: Sea breeze is a research topic. Over the lifetime, 2544 publications have been published within this topic receiving 55651 citations.

Impact of Bay-Breeze Circulations on Surface Air Quality and Boundary Layer Export

Abstract: Meteorological and air-quality model simulations are analyzed alongside observations to investigate the role of the Chesapeake Bay breeze on surface air quality, pollutant transport, and boundary layer venting. A case study was conducted to understand why a particular day was the only one during an 11-day ship-based field campaign on which surface ozone was not elevated in concentration over the Chesapeake Bay relative to the closest upwind site and why high ozone concentrations were observed aloft by in situ aircraft observations. Results show that southerly winds during the overnight and early-morning hours prevented the advection of air pollutants from the Washington, D.C., and Baltimore, Maryland, metropolitan areas over the surface waters of the bay. A strong and prolonged bay breeze developed during the late morning and early afternoon along the western coastline of the bay. The strength and duration of the bay breeze allowed pollutants to converge, resulting in high concentrations locally near the bay-breeze front within the Baltimore metropolitan area, where they were then lofted to the top of the planetary boundary layer (PBL). Near the top of the PBL, these pollutants were horizontally advected to a region with lower PBL heights, resulting in pollution transport out of the boundary layer and into the free troposphere. This elevated layer of air pollution aloft was transported downwind into New England by early the following morning where it likely mixed down to the surface, affecting air quality as the boundary layer grew.

A multi-year study of sea breezes in a Mediterranean coastal site: Alicante (Spain)

Abstract: Using 6-year data collected in a high-resolution network of 19 stations in the province of Alicante (Spain), the characteristics of sea breezes for the period 2000–2005 were studied This study attempts to develop a multi-year climatology of sea breeze flows focusing on a Western Mediterranean coastal site We used half-hourly meteorological records from a reference station in Alicante and sea surface temperature measurements at Albufereta beach to identify past sea breeze episodes, on the basis of an objective selection technique A total of 475 sea breeze events during the 6-year period were identified and the following parameters were determined: mean time of onset, mean wind speed and direction at the time of onset, mean time of cessation, mean temporal dimension (duration), mean maximum velocity, mean time of maximum velocity and mean wind path of the sea breeze The mean onset and cessation times are 0940 UTC and 2009 UTC (local standard time = UTC + 0100 h, or + 0200 h with daylight-saving time), respectively, with a mean duration of 1029 h The mean wind speed at the time of the passage of sea breeze fronts is low (207 m s−1), but sea breeze gust intensities range from 36 to 116 m s−1 and they generally occur during 1200–1300 UTC Southerly and southeasterly onset flows dominate in winter, whereas more easterly onsets occur in spring and summer The mean inland directed wind path of the sea breezes is 977 km with noteworthy differences throughout the year; a case study showed onshore wind peaks of 111 m s−1, 50-km inland of the Vinalopo river valley in the late afternoon The spatial and temporal change in wind speed and direction were also analysed, using multi-year wind hodographs for the 19 stations and eight well-defined synoptic patterns favouring the development of sea breezes Copyright © 2009 Royal Meteorological Society

Meteorological Processes and Ozone Exceedances in the Northeastern United States during the 12–16 July 1995 Episode*

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 ...

A five‐year study of coastal recirculation and its effect on air pollutants over the East Mediterranean region

Abstract: [1] Many studies have shown that air pollutants concentrations in coastal cities may be gravely affected by coastal recirculation. In this study an attempt is made to examine the properties of coastal recirculation over a long period (5 yrs) at multiple sites along the East Mediterranean Sea (EMS). For this purpose, a single station quantitative measure of horizontal recirculation is used based on wind field measurements over periods of 1–96 hrs. The horizontal recirculation is examined with respect to the integration time period, synoptic flow, seasonality, coastline variations, elevation, and air pollutants concentrations. The interaction between synoptic and mesoscales is shown to be a governing factor by allowing or overruling the land sea breeze winds. Favorite conditions for coastal recirculation are shown to be light or variable winds such as under a Cole or a High-Pressure system. The monthly distribution of the recirculation potential has a bimodal behavior with two peaks during the transitional seasons and October in particular. This is as a result of the annual cycle of night-time land-sea temperature difference driving the land breeze and the more frequent passage of synoptic scale flows with an easterly wind component at the EMS. Two factors leading to variations along the coastline are the urban heat island, weakening the breeze winds and reducing recirculation potential, and the concaved shape of the southern shoreline that causes a convergence and strengthening of the land breeze, thus supporting recirculation. The primary pollutants NOx and SO2 have the highest concentrations during weak daily mean wind speeds. O3 levels depict an almost opposite image of NOx, with higher values for both high and low recirculation, possibly resulting from either long range transport or coastal recirculation.