Defence of dissertation in the field of water engineering, Tero Niemi, M.Sc. (Tech.)
Improved Precipitation Information for Hydrological Problem Solving – Focus on Open Data and Simulation.
The public examination of the doctoral dissertation of Tero Niemi, M.Sc. (Tech.), will be held on 1st September 2017 at 12.00 at the Aalto University School of Engineering. The title of the dissertation is Improved Precipitation Information for Hydrological Problem Solving – Focus on Open Data and Simulation. Field of the dissertation is water engineering.
Precipitation is ultimately the source of all fresh water over land. Therefore, knowing the rate and the total amount of precipitation in a given time is often the first step in many hydrological assessments. The amount of open data is constantly increasing, including also precipitation data. Nevertheless, since measuring everything is impossible, precip- itation simulations are still necessary to study e.g. very rare or future scenarios.
This thesis studied the opportunities of utilizing openly available rain gauge and weather radar precipitation products in urban hydrological assessments. The results show that a gauge close to the point of interest is still the best precipitation information source for small urban catchments. However, as the distance grows, radar data can outperform gauge data even at urban catchments much smaller than the radar data resolution. As the openly available radar products improve, they will become even more useful in the urban settings.
An important but often neglected feature in precipitation simulation models is the proper description of the shape of precipitation fields. A method developed in the thesis to better quantify the shape of precipitation fields during a rain event offers a practical improve- ment to the existing precipitation simulation models. Indeed, simulations performed us- ing a traditional and an upgraded precipitation simulation model showed how describing the shape more precisely allows for more realistic simulation results.
Opponent: Professor Emeritus Geoffrey Pegram, University of KwaZulu-Natal, South Africa
Supervisor: Professor Harri Koivusalo, Aalto University School of Engineering, Department of Built Environment
Electronic dissertation: http://urn.fi/URN:ISBN:978-952-60-7511-2
Contact information: Tero Niemi, email@example.com