Sea breeze

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

Summer Shower Distribution Over the Florida Peninsula as Deduced from Digitized Radar Data

Abstract: Radar echoes over the Florida peninsula have been recorded manually every 3 hr on a 7.5 by 7.5 mi grid during the past three summers. This note summarizes the echo distribution for the period May through August 1963. The spatial and temporal variations of convective activity were found to be highly correlated with the sea breeze.

Diurnal winds around lake Tanganyika

Abstract: Regular diurnal variations of coastal winds are observed around Lake Tanganyika during the dry season, when insolation is intense and the prevailing trade winds are weak. the long deep lake is at the bottom of the East African rift valley. A two-dimensional mesoscale model across the schematic rift-valley topography is used to study these local tropical winds. the full model gives a good simulation when compared with the observed winds on the east coast. It turns out that about half of the strong diurnal wind variation there, in the form of slope winds, is due to the sloping mountains. Roughly one quarter is due to the thermal lake effect (sea breeze), and one quarter is due to the existence of the south-easterly trade wind, which enhances the sea-breeze circulation component considerably during daytime, and adds on to the downslope winds during night-time. the wind field across the lake is quite variable from hour to hour and from place to place, yet predictable to a good extent during the dry season, when the external conditions are rather similar from day to day.

Response of London's urban heat island to a marine air intrusion in an easterly wind regime

Abstract: Numerical simulations are conducted using the Weather Research and Forecast numerical model to examine the effects of a marine air intrusion (including a sea-breeze front), in an easterly wind regime on 7 May 2008, on the structure of London’s urban heat island (UHI). A sensitivity study is undertaken to assess how the representation of the urban area of London in the model, with a horizontal grid resolution of 1 km, affects its performance characteristics for the near-surface air temperature, dewpoint depression, and wind fields. No single simulation is found to provide the overall best or worst performance for all the near-surface fields considered. Using a multilayer (rather than single layer or bulk) urban canopy model does not clearly improve the prediction of the intensity of the UHI but it does improve the prediction of its spatial pattern. Providing surface-cover fractions leads to improved predictions of the UHI intensity. The advection of cooler air from the North Sea reduces the intensity of the UHI in the windward suburbs and displaces it several kilometres to the west, in good agreement with observations. Frontal advection across London effectively replaces the air in the urban area. Results indicate that there is a delicate balance between the effects of thermal advection and urbanization on near-surface fields, which depend, inter alia, on the parametrization of the urban canopy and the urban land-cover distribution.

Precipitation over urban areas in the western Maritime Continent using a convection-permitting model

Abstract: This study investigates the effects of urban areas on precipitation in the western Maritime Continent using a convection-permitting regional atmospheric model. The Weather Research and Forecasting model was used to simulate the atmosphere at a range of spatial resolutions using a multiple nesting approach. Two experiments (with and without urban areas) were completed over a 5-year period (2008–2012) each to estimate the contribution of cities to changes in local circulation. At first, the model is evaluated against two satellite-derived precipitation products and the benefit of using a very high-resolution model (2-km grid spacing) over a region where rainfall is dominated by convective processes is demonstrated, particularly in terms of its diurnal cycle phase and amplitude. The influence of cities on precipitation characteristics is quantified for two major urban nuclei in the region (Jakarta and Kuala Lumpur) and results indicate that their presence locally enhances precipitation by over 30 %. This increase is mainly due to an intensification of the diurnal cycle. We analyse the impact on temperature, humidity and wind to put forward physical mechanisms that explain such changes. Cities increase near surface temperature, generating instability. They also make land-sea temperature contrasts stronger, which enhances sea breeze circulations. Together, they increase near-surface moisture flux convergence and favour convective processes leading to an overall increase of precipitation over urban areas. The diurnal cycle of these effects is reflected in the atmospheric footprint of cities on variables such as humidity and cloud mixing ratio and accompanies changes in precipitation.