A multi-method investigation of the urban impact on precipitation

01 October 2023 → 31 October 2023
Regional and community funding: Special Research Fund
Research disciplines
  • Natural sciences
    • Modelling and simulation
    • Computational physics
Climate modelling Urban climate Extreme precipitation
Project description

Our planet is highly urbanised and cities impact the atmosphere. This impact is not limited to increased temperatures, but studies also show an impact on precipitation. On average an increase in precipitation is found over and downwind of cities. Given that climate change leads to an increased frequency and intensity of extreme precipitation, it is important to clarify this urban impact on precipitation. Due to the nonlinearity of the relevant atmospheric processes and many other factors that influence precipitation, studying the relation between cities and precipitation is very challenging. I therefore propose a novel multi-method approach to investigate this phenomenon for the first time over Belgium. Firstly, several observations, including rain gauges, radar and lightning detection, will be combined to investigate a potential urban fingerprint over Belgium. Secondly, a 10-year high resolution climate model run, which accuratel resolves both cities and deep convection, will be performed with and without cities to assess their impact on precipitation. Finally, the urban impact on two extreme precipitation cases, including the July 2021 floods in Wallonia, will be revisited using an ensemble approach. By using two convection-permitting models and multiple ensemble members, I will be able to quantify the uncertainty of the results. The study focuses on Belgium but the state-of the-art multi-method approach will be relevant to the international urban climate community.