The urban climate of Amsterdam: Results of 10 years Amsterdam Atmospheric Monitoring Supersite

The urban climate is substantially different from its rural counterpart. This study summarizes 10 years of monitoring the urban climate of Amsterdam. Amsterdam has a unique position in the sense it is located in a delta, and located close to a large lake in the east. Moreover the city is well known for its large amount of water bodies. A network of 24 weather stations has been employed observing temperature, humidity and wind speed at 4 m height across the city. This is complemented by radio soundings, and traverse observations using a tricycle equipped with a weather station recording temperature, humidity wind speed, and all radiation components within the urban canyon. The network also contains flux measurements of turbulent fluxes of heat, moisture, momentum, carbon dioxide and methane using eddy covariance observations. The latter are especially relevant for monitoring the greenhouse footprint of the city. In addition a microwave scintillometer has been installed to monitor the sensible and latent heat flux for a footprint over the city as a whole. We present spatial behaviour of temperature (urban heat island and urban cool island) and humidity as well as canyon wind speeds. Both a clear urban heat island (UHI) and cool island has been found. The UHI extends up to 90 m. In addition, the observations reveal a systematic signal of a moisture island effect too. We find a Bowen ratio of the summertime fluxes about 3.8. Finally results from indoor weather stations installed in 100 households to monitor and understand urban heat in bed and living rooms will be presented.