Urban features essentially influence atmospheric flow and microclimate, strongly
enhance atmospheric turbulence, and modify turbulent transport, dispersion, and
deposition of atmospheric pollutants (e.g., Piringer et al., 2007). Increased resolution
in numerical weather prediction (NWP) models allows for a more realistic
reproduction of urban air flows and air pollution processes, however most of the
operational models still do not consider, or consider very poorly, the urban effects.
This has triggered new interest in model development and investigation of processes
specific to urban areas. Recent developments performed as part of the European
project FUMAPEX on integrated systems for forecasting urban meteorology and
air pollution (Baklanov et al., 2002, 2005), the US EPA and NCAR communities
for MM5 (Dupont et al., 2004; Bornstein et al., 2006; Taha 2008), WRF models
(Chen et al., 2006), and other relevant studies (see e.g. Baklanov and Grisogono,
2007) have shown many opportunities in the “urbanization” of weather forecasting
and atmospheric pollution dispersion models.