THE INTERNATIONAL ASSOCIATION FOR URBAN CLIMATE

Europe

air pollution and environmental impact assessment: the mutlimedia information source

Germany - Deutschland

German Engineering Society - Verein Deutscher Ingenieure (VDI)
Kommission Reinhaltung der Luft - KRdL
Environmental Information - Umweltinformationen (Bund, Land, Kommunen)
DIFU
German Weather Service - Deutscher Wetterdienst (DWD)
Cities - Städte

Windkanal live - wind tunnel live

COST, European Cooperation in the field of Scientific and Technical Research COST action 615 "Better Air in European Cities-Database, Monitoring and Modelling of Urban Air Pollution

Some explanation and examples about Urban Climate (from Karten Brandt)

Switzerland

World Meteorological Organization (WMO)
World Health Organization (WHO)

USA
urbanclimate.org

EcoGateway Homepage - Air & Atmosphere