Pattern: Advantages of High Resolution Weather Radar Networks
Precipitation observations with radars operating in the X-Band frequency range are essential to meet present and future requirements for flood forecasting, water management and other hydro-meteorological applications. Besides higher resolution, these systems are cost-effective compared to S- or C-band radars because of smaller antenna size. Disadvantages of single X-Band radars are the large influence of attenuation by liquid water and a relatively short range.
The project Precipitation and ATTenuation Estimates from a high resolution weather Radar Network (PATTERN) intends to demonstrate that a network of High Resolution Weather Radars (HRWR) can overcome this apparent drawback. Therefore, the University of Hamburg and the Max Planck Institute for Meteorology set up a network consisting of four modified ship navigation radars near Hamburg, Germany. The network is operational since January 2012. Each radar has a maximum range of 20 km with 60 m spatial and 30 s temporal resolution. A large area in the network is covered by at least two radars at the border and up to four radars in the center. Several rain stations consisting of a Micro Rain Radar (MRR) and a rain gauge complement the network. These stations are used to calibrate and evaluate the quality of the X-Band radars.
The aim of this presentation is to identify advantages and disadvantages of the network as well as single X-Band radars. I will give a short description of the algorithms used to derive precipitation from reflectivity measurements with a focus on those algorithms exploiting the benefits of having a network, e.g. for clutter removal and replacing disturbed pixels by measurements from other radars instead of interpolating. A comparison to measurements of the weather radar operating in C-Band used by the German Weather Service will focus on the ability of high resolution observations to give information about small scale structures of rain events. Furthermore, I will describe the specifications of the modified HRWR systems as well as the design of the network.