Numerical modelling of pollutant dispersion in sea breeze conditions

Abstract

Abstract. The characteristics of air pollution in Tarragona (Spain) were investigated. Tarragona has an important petrochemical industry in a coastal region with a complex terrain. The numerical study was made in sea breeze conditions with a three-dimensional mesoscale model. Temporal and spatial variations of the wind fields have been used in the Eulerian equation for a non-reactive pollutant. The results of this study reveal the complexity of the dispersion patterns due to the combined effects of the sea breeze circulation and the orography. This work presents a comparison between the model output and the observed wind data by sodar and surface wind measurements. The evaluation shows that the model is capable of providing very realistic wind fields within this domain.

Pollutant transport in coastal areas with and without background wind

“…This minor dierences can be justi®ed by the fact that the large-scale wind blows the pollutant southeastwards reducing the concentration at the measuring station also producing a delay in the In a previous work (Camps et al, 1996), the pollutant dispersion in the analyzed area under similar sea breeze conditions was computed using an Eulerian approach. In that case the advection-diusion equation was solved at each time step using the instantaneous wind ®eld.…”

“…For instance, in the lowest level of the model, the grid space is 4 m. The top of model domain is assumed at 100 hPa. The model was initialized at 0400 LST (Camps et al, 1996), and the computations where carried out for a period of 24 h. Thermodynamical variables were initialized using a summer climatological rawinsonde (Camps et al, 1996). The thermal strati®cation corresponds to the standard atmosphere dTadz % À6 K km À1 , and the humidity varies near linearly from 12 g/Kg at the surface to 3 g/Kg at a height of 6 km.…”

Pollutant transport in coastal areas with and without background wind

“…In a previous work (Camps et al, 1996), the pollutant dispersion in the analyzed area under similar sea breeze conditions was computed using an Eulerian approach. In that case the advection-diusion equation was solved at each time step using the instantaneous wind ®eld.…”

“…The numerical experiment consists of a study of the land and sea breeze in the region of Tarragona, located in northeast Spain near the Mediterranean Sea (Camps et al, 1996). The detailed orography of the zone is depicted in Fig.…”

Impact of Sea Breeze Circulation on the Transport of Ship Emissions in Tangshan Port, China

“…Various mechanisms of sea breeze circulations affecting the air quality in coastal areas have been proposed and reviewed by many researchers [32][33][34][35][36][37][38][39], e.g., the recirculation of pollutants associated with sea breezes and the thermal internal boundary layer (TIBL) are often designated as the causes of persistent air pollution problems in coastal areas [32]. (1) Recirculation of pollutants.…”