Heavy Precipitation Events in the Mediterranean: The Impact of Ensemble-Based Assimilation of Thermodynamic Lidar Profiles on the Analyses and Forecasts of the Pre-Convective Environment, Convection Initiation and Probabilistic Quantitative Precipitation Forecasts

• Applicant: Professor Dr. Volker Wulfmeyer
• Subject Area: Atmospheric Science
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 510787943

The Water vapor Lidar Network Assimilation (WaLiNeAs) project involves several research institutes across Europe. Their expertise is combined to get an insight into the potential of a network of advanced thermodynamic lidar systems for short-range probabilistic quantitative precipitation forecasting (PrQPF) of heavy precipitation events (HPEs) in the Mediterranean. The WaLiNeAs observation network will be set up and operated for three months from the beginning of September 2022. This proposal aims to join the unique WaLiNeAs project and to collaborate with its research team with respect to the performance of thermodynamic measurements using the Atmospheric Raman Temperature and Humidity Sounder (ARTHUS) of the Institute of Physics and Meteorology (IPM) at the University of Hohenheim. Furthermore, the WaLiNeAs measurements will be applied for advanced data assimilation studies with respect to their impact on the prediction of the pre-convective environment, convection initiation, and HPEs. The overarching goal of this proposal is to investigate the following hypotheses:An advanced representation of the pre-convective environment in the Mediterranean by a network of thermodynamic Raman lidar systems will lead to 1) a more accurate initialization and simulation of the pre-convective environment as well as convection initiation, 2) an improvement in PrQPF of HPEs.During the WaLiNeAs campaign, six autonomous water-vapor Raman lidar systems will be deployed for continuous measurements throughout the intensive observation periods (IOPs). All their data will be collected, disseminated, and monitored in real-time.Specifically, we will examine our hypotheses by attaining the following research objectives: I) Design an efficient regional, hybrid, ensemble-based, short-range weather forecast system for predicting HPEs in the Mediterranean region based on the WRF-NOAHMP model system, II) investigate the improvement of the forecast skill with respect to convection initiation and PrQPF of HPEs by data assimilation of temperature and humidity profiles from the WaLiNeAs lidar network, and III) analyze the ARTHUS data and derive moisture and temperature statistics during the experiment.These research objectives will pave the way for future data assimilation strategies and understanding of the importance and density of thermodynamic lidar networks for short-range forecasting of extreme events. This will be a joint effort of scientists from Laboratoire atmosphères, milieux, observations spatiales (LATMOS), the Centre National de Recherches Météorologiques (CNRM) in France, and the National Oceanic and Atmospheric Administration (NOAA) in the USA.

• DFG Programme: Research Grants
• International Connection: France, USA
• Cooperation Partners: Dr. Olivier Caumont; Professor Dr. Cyrille Flamant; Professor David D. Turner, Ph.D.
• Co-Investigator: Dr. Rohith Thundathil