Project Details
Combining radar POlarimetry, weather forecast MOdel outputs and DOppler radar observations for Riming analysis~(POMODORI)
Applicants
Dr. Michael Frech; Dr. Stefan Kneifel
Subject Area
Atmospheric Science
Term
since 2018
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 408012686
Riming can efficiently transform cloud supercooled liquid water into ice and therefore has a strong impact on the formation and evolution of precipitation. Yet, riming is difficult to identify, or even quantify, in remote sensing observations and to faithfully represent in atmospheric models. Commonly, only intense riming in the form of graupel is considered in observational and modeling studies. To gain a better quantitative understanding of the riming process, PROMPOMODORI will combine scanning polarimetric measurements from the German C-band weather radar network, operational short-term weather predictions from DWD’s ICON-D2 forecast model, and vertically pointing Doppler measurements from high-resolution cloud radars operated at JOYCE in Jülich and at the Meteorological Institute of the University of Munich, and, which is unique, also from the Cband radars of the German weather radar network. Vertically pointing Doppler radar measurements will be used to retrieve the degree of riming throughout a narrow atmospheric column above the radar by exploiting the effect of riming on particle terminal fall velocity. These riming retrievals will then be correlated with the spatial fields of CBand polarimetric moments and ICON-D2 (thermo)dynamic variables by employing a machine learning approach using JOYCE cloud radar data. By essentially transferring the (local) riming retrievals from Doppler radar measurements to the (spatial) fields of polarimetric and thermodynamic variables, PROM-POMODORI will investigate the spatial variability of riming in precipitating clouds for typical precipitation conditions over parts of southern Germany. PROM-POMODORI will investigate how the variability derived from the riming retrievals relates to the ICON-D2 grid resolution and whether significant spatial variability of riming is observed on a sub-grid scale. PROM-POMODORI will also explore whether the quantitative identification of riming has the potential to be used as an indicator of aircraft icing, by comparing the retrieval results with the DWD ADWICE system, which provides maps of regions with icing potentialcritical for air traffic.
DFG Programme
Priority Programmes
International Connection
Finland, Switzerland
Cooperation Partners
Jussi Leinonen, Ph.D.; Professor Dr. Dmitri Moisseev