A large share of global climate risk is concentrated in urban areas. Cities are vulnerable because of the high density of people and built infrastructure. In addition, urban areas shape their own climate, amplifying climate extremes such as excessive heat and flooding.  Recently, we demonstrated that, because of the urban heat island effect, cities experience twice as many heat wave days than their rural surroundings. The UrbClim model developed at VITO is unique in its capability of simulating long time periods at a high spatial resolution (~100 m) and at an affordable computational cost, while not compromising on accuracy.

Your challenges

To assess the urban climate of an entire urban area at once
To develop data-based urban adaptation strategies and action plans
To increase awareness of the effects of climate change in urban environments

Key applications

  • Urban climate assessments deliver local policy makers an objective evaluation about the presence and the intensity of the urban heat island and heat stress in their city.
  • Short-term urban climate forecasts deliver daily forecasts of the heat stress conditions in your city.
  • Future climate projections for discovering how global climate change will influence individual cities.
  • Adaptation scenarios and impact assessments to discover how green/blue measures can affect your urban climate.
VITO - UrbClim

UrbClim main specifications

  • The model solves a set of simplified prognostic flow equations for the atmospheric boundary layer, and contains detailed urban surface physics.
  • Raw hourly output fields of basic meteorological quantities (temperature, humidity, wind speed components), are generally further combined or aggregated to yield, e.g., the number of heat wave days or cooling degree days.
  • Compared to traditional ‘urbanized’ mesoscale atmospheric models, UrbClim is faster by more than two orders of magnitude. As a result, it is one of the only models worldwide that is capable of conducting simulations of sufficient length (tens of years) and number (nested within an ensemble of large-scale climate models) to be of relevance for the generation of proper local climate statistics, including an uncertainty range.
  • The model has undergone extensive validation for several cities (Antwerp, Almada, Athens, Barcelona, Berlin, Bilbao, Brussels, Ghent, London, Paris, Skopje).
  • For more detailed information about the UrbClim model: De Ridder, K., D. Lauwaet, and B. Maiheu, 2015. UrbClim – a fast urban boundary layer climate model. Urban Climate, 12, 21-48.


The UrbClim model is the result of protracted development. Today, it has already been used successfully in many cities worldwide (Almada, Antwerp, Barcelona, Berlin, Bern, Bilbao, Brussels, Delhi, Ghent, Hasselt, London, Paris, Praque, Rome, Skopje, Tilburg and Vienna). UrbClim is also used in several service projects for local, regional, national and international organisations.

Business Development
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