On the effect of land use change on the meteorological parameters above the greater Athens area

Abstract

The rapid land use changes that took place in the Greater Athens Area (GAA) the past decades, due to the expansion of the urban grid, have changed the landscape of Attica significantly. Areas that were covered by low vegetation in the past are now replaced by roads (e.g. Attiki Odos) and new towns. On the other hand, accurate and updated data of land use are necessary for simulating the meteorological fields above urban areas, which in turn are given as input to photochemical models in order to study the dispersion of pollutants above urban areas. The purpose of the present work is to study the effects of land use changes on the meteorological parameters, such as wind speed profiles and temperature. For this reason, the meteorological mesoscale model MM5 was applied, using updated land use data. The model ran with the grid nesting method using two grids, the fine one covering the GAA with a spatial resolution of 5 × 5 km2. Results showed that the land use changes affected wind and temperature fields. Wind velocities decreased above areas covered by urban grid that were previously characterised as shrub land, while above the rapidly developing eastern suburbs of Attica an increase in velocities appeared.