Air pollution transport by the land-sea breeze

Dr Helen Dacre

Poor air quality can have a serious impact on human health, to the extent that during August 2003 between 225 and 593 deaths in the UK were directly attributed to enhanced pollution levels. Local air quality is, to a large degree, determined by the transport of pollution by meteorological processes. Since approximately 40% of the world's population live within 100km's of the coast it is especially important to accurately forecast meteorological processes that occur within coastal zones. One of the most important processes is the land-sea breeze which occurs as a result of the difference in air temperature over land and sea. The highly variable winds near the coast may sweep pollutants out to sea on a land breeze but then bring them back with the sea breeze. More accurate estimates of the fine-scale structure of the sea breeze front, including the associated vertical motions associated with these wind systems are critical for determining the layers at which pollutants will ultimately reside and the horizontal direction in which direction they will move. This project aims to carry out a comprehensive study of pollution transport by the land-sea breeze using chemical tracers within the UK Met Office forecast model. These simulations will then be evaluated and validated using observational data.