New session at EGU 2014: Precipitation and urban hydrology

by Marie-Claire ten Veldhuis / TU Delft

The RainGain team initiated a new session at the European Geoscience Union General Assembly (Wien, 28 April - 2 May 2014), on the topic of precipitation measurement and hydrological modelling in cities.

Several examples were presented of X-band radars applied in cities: in Central Italy (Mediterranean region), Hamburg and in the Dallas-Fortworth metroplex in the US. Different types of radars were chosen for these applications, based on cost considerations and directly available technology. The presentations made clear that there is a trade-off between quality and costs: cheaper radars are typically used in combination with national C-band radar networks, while more advanced radars provide independent and more accurate measurements.

These presentations were followed by demonstrations of applications of high resolution rainfall data in urban hydrological models. The audience was impressed by the powerful visualisation and computing capabilities of the 3Di model. In the two presentations related to RainGain pilot sites, one demonstrated sensitivity of urban hydrological models to precipitation variability, while the other showed, in a comparison of four pilot sites, how different catchment characteristics lead to really different responses of the hydrological systems.

Later that day, poster summaries and discussion were organised for the same session. Three topics were discussed: the potential  of rainfall retrieval from GSM antenna links in cities, rainfall data retrieval and simulation based on merged radar and rain gauges data sources and hydrological response in cities as a result of ongoing urbanisation and in relation to the spatial resolution of precipitation data.

The session "Precipitation and urban Hydrology" was chaired by the RainGain project coordinator, Marie-Claire ten Veldhuis, and four presentations (orals and posters) were held by RainGain researchers:

• "Modelling of the peri-urbain catchments with the help of a modular physically-based model : Mutli-Hydro" by Agathe Giangola-Murzyn, Auguste Gires, Julien Richard, Abdellah Ichiba, Ioulia Tchiguirinskaia, and Daniel Schertzer;
• "Transfer of spatio-temporal multifractal properties of rainfall to simulated surface runoff” Auguste Gires, Agathe Giangola-Murzyn, Julien Richard, Jean-Baptiste Abbes, Ioulia Tchiguirinskaia, Daniel Schertzer, Bernard Willinger, Hervé Cardinal, and Thomas Thouvenot;
• "Sensitivity of urban hydrodynamic modelling to high resolution radar rainfall" by Guendalina Bruni, Ricardo Reinoso, Nick van de Giesen, Francois Clemens, and Marie-Claire ten Veldhuis;
• "Comparing two radar rainfall products with the help of Multifractal Analysis” by Abdellah Ichiba, Auguste Gires, Ioulia Tchiguirinskaia, Philippe Bompard, and Daniel Schertzer;
• "Multi-storm, multi-catchment investigation of rainfall spatial resolution requirements for urban hydrological applications" by Susana Ochoa Rodriguez, Marie-Claire ten Veldhuis, Guendalina Bruni, Auguste Gires, Johan van Assel, Lipen Wang, Ricardo Reinoso-Rodinel, Abdellah Ichiba, Stefan Kroll, Daniel Schertzer, Christian Onof, and Patrick Willems;
• "Singularity-sensitive merging of radar and raingauge rainfall data"  by Li-Pen Wang, Patrick Willems, Susana Ochoa-Rodriguez, and Christian Onof.

RainGain was also represented by the Met Office and École des Ponts ParisTech at the following orals and poster presentations:

• "Insights into the 3+1 D structure of rainfall through a multifractal analysis of 2DVD data” by Auguste Gires, Ioulia Tchiguirinskaia, Daniel Schertzer, and Alexis Berne;
• "Teaching (an introduction to!) fractals and rainfall features in kinder garden" by Auguste Gires, Mélanie Villepoux, and Valérie Rouellé;
• "A high-resolution C-band radar composite for urban hydrological modelling” by Caroline Sandford, Tim Darlington, Selena Georgiou, Jacqueline Sugier, and Katie Norman;
• "Communication on urban resilience to extreme weather: challenges and achievements in the dialogue between the international scientific community and local stakeholders” by  Rosa Vicari, Auguste Gires, Ioulia Tchiguirinskaia, and Daniel Schertzer;
• "Assessing the impact of science communication in the development of resilient cities to extreme weather” by Rosa Vicari, Auguste Gires, Ioulia Tchiguirinskaia, and Daniel Schertzer.