The set-up and evaluation of fine-scale data assimilation for the urban climate of Amsterdam

Sytse Koopmans*, Ronald van Haren, Natalie Theeuwes, Reinder Ronda, Remko Uijlenhoet, Albert A.M. Holtslag, Gert Jan Steeneveld

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

3 Citations (Scopus)
62 Downloads (Pure)


Ongoing urbanization highlights the need for a better understanding and high resolution modelling of the urban climate. In this study, we combine rural observations by WMO surface stations, weather radar data and urban crowd-sourced observations with very fine-scale modelling efforts for Amsterdam, The Netherlands. As a model, we use the Weather Research and Forecasting (WRF) mesoscale model with 3D variational data assimilation at a 100-m resolution in the innermost model domain. In order to enable the assimilation of observations within the urban canopy, we develop a scheme to reduce urban temperature biases by adjusting urban fabric temperatures. The scheme is tested against independent urban observations for the summer month of July 2014 and specifically for a hot period and an extreme precipitation event. We find data assimilation reduces biases in temperature and wind speed. Within the city, the most significant improvement is the reduction of negative temperature biases during clear nights, which implies a better prediction of the Urban Heat Island (UHI). Concerning precipitation, the fractional skill score improves incrementally when additional observations are assimilated, and the largest impact is seen from the assimilation of weather radar observations.

Original languageEnglish
Pages (from-to)171-191
Number of pages21
JournalQuarterly Journal of the Royal Meteorological Society
Issue number750
Publication statusPublished - 2022


Dive into the research topics of 'The set-up and evaluation of fine-scale data assimilation for the urban climate of Amsterdam'. Together they form a unique fingerprint.

Cite this