Impact of a sea breeze on the boundary-layer dynamics and the atmospheric stratification in a coastal area of the North Sea

Abstract

In-situ sodar and lidar measurements were coupled with numerical simulations for studying a sea-breeze event in a flat coastal area of the North Sea. The study's aims included the recognition of the dynamics of a sea-breeze structure, and its effects on the lower troposphere stratification and the three-dimensional (3D) pollutant distribution. A sea breeze was observed with ground-based remote sensing instruments and analysed by means of numerical simulations using the 3D non-hydrostatic atmospheric model Meso-NH. The vertical structure of the lower troposphere was experimentally determined from the lidar and sodar measurements, while numerical simulations focused on the propagation of the sea breeze inland. The sea-breeze front, the headwind, the thermal internal boundary layer, the gravity current and the sea-breeze circulation were observed and analysed. The development of a late stratification was also observed by the lidar and simulated by the model, suggesting the formation of a stable multilayered structure. The transport of passive tracers inside the sea breeze and their redistribution above the gravity current was simulated too. Numerical modelling showed that local pollutants may travel backward to the sea above the gravity current at relatively low speed due to the shearing between the landward gravity current and the seaward synoptic wind. Such dynamic conditions may enhance an accumulation of pollutants above coastal industrial areas.

Sea and Lake Breezes: A Review of Numerical Studies

“…The earliest hydrostatic models used simple boundary-layer schemes and neglected moisture, latent heating, radiation, and land-surface parametrisations. Some later models included radiation, moisture and latent heating, with increasingly sophisticated schemes for surface heating and the turbulent Neumann andMahrer (1971, 1974) 5 , Pearson (1973) Pielke (1974a,b) 4 1975-1979 2D 2.5-8 9 Neumann and Mahrer (1975) 5 , Sheih and Moroz (1975) 1 , Estoque et al (1976) 1 , Pielke (1976, 1977) 3 , Physick (1976) 4 , Anthes (1978) 2 , Asai and Mitsumoto (1978) 1 , Ookouchi et al (1978) 3 1980-19842D 3-10 8 Physick (1980 4 , Estoque and Gross (1981) 1985-1989 2D 1-10 14 Garratt and Physick (1985) 2 , Mahrer and Segal (1985) 1 , Physick and Smith (1985) 3 , Neumann and Savijarvi (1986) 1 , Noonan and Smith (1986) 2 , Segal et al (1986) 3 , Arritt (1987Arritt ( , 1989 4 , Briere (1987) 1 , Anthes (1987, 1988) Freitas et al (2007) 8 , Srinivas et al (2007) 8 , Talbot et al (2007) 8 , Thompson et al (2007) 8 , Cheng and Byun (2008) transport of heat, moisture, and momentum. Through the 1970s, turbulence in the surface layer was generally treated using simple K-theory, assuming constant fluxes, and with empirical formulations for turbulent transport in the overlying transition layer.…”

“…For high (low) N, circulation less (more) sensitive to area of surface heating and geostrophic wind Feliks (1993), Xian and Pielke (1991), Tijm et al (1999a), Talbot et al (2007) Initial inversion strength, initial boundary-layer depth, terrain slope, and multiple inversions also factors…”

“…Since 1990, a number of two-and three-dimensional idealized numerical studies have been made at a horizontal grid spacing of approximately 100 m, where most boundary-layer turbulence is explicitly resolved (e.g, Hadfield et al 1991Hadfield et al , 1992Sha et al 1991Sha et al , 1993Sha et al , 2004Fovell and Dailey 2001;Letzel and Raasch 2003;Antonelli and Rotunno 2007;Cunningham 2007;Talbot et al 2007). These large-eddy simulations (LES) provide insight into the fine-scale structure of sea breezes and interactions between sea breezes and boundary-layer features, such as lobe and cleft instabilities and horizontal convective rolls (Fig.…”

The Growth of the Planetary Boundary Layer at a Coastal Site: a Case Study

“…However, few address the problem of its diurnal evolution (Martano 2002;Talbot et al 2007); most of the available studies in the Mediterranean Sea are concentrated in large agglomerations such as Athens (Melas and Kambezidis 1992;Batchvarova and Gryning 1998), Barcelona (Sicard et al 2006), Marseille (Delbarre et al 2005;Lemonsu et al 2006), Naples (Boselli et al 2009), Rome (Mastrantonio et al 1994) and Thessaloniki (Santacesaria et al 1998). In such cases the presence of urban areas and complex orography further complicate the analysis.…”

Padrões das circulações atmosférica e oceânica na região de ressurgência costeira de Cabo Frio

“…Análises de temperatura através de alquenonas indicaram que os padrões de resfriamento da ressurgência na área de Cabo Frio se intensificaram nos últimos 700 anos (Mahiques et al, 2005). A TSM mais fria também pode ter impacto em processos locais atmosféricos como a brisa marítima, influenciando o tempo e também o transporte e a deposição de poluentes (Gilliam et al, 2004;Talbot et al, 2007;Bastin e Drobinski, 2006;Bouchlaghem et al, 2007;Clappier et al, 2000). Apesar da sua importância, poucos trabalhos investigaram a interação oceanoatmosfera em Cabo Frio e seu impacto nos padrões locais de tempo e clima.…”