Quantifying the role of diabatic processes for forecast errors associated with mid-latitude weather systems - A combined observational, diagnostic and modelling approach (DIAP)

• Applicants: Dr. Andreas Dörnbrack; Professor Dr. Heini Wernli
• Subject Area: Atmospheric Science
• Term: from 2008 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 36043686

Diabatic processes can strongly influence the evolution and intensity of mid-latitude weather systems. These processes are associated with latent heat release due to phase transitions of water, surface fluxes, or radiative effects, and they strongly depend on the transport of water vapour that often occurs in narrow airstreams. It is difficult to quantitatively assess these processes from standard meteorological data. Therefore, this project will (1) use novel datasets from the YOTC project, humidity observations from previous field experiments, and numerical model techniques to better diagnose and quantify the role of theses processes for the evolution of different mid-latitude weather systems, including cyclones, blockings, and jet streams. Investigating the forecast accuracy of these systems and performing high-resolution model sensitivity experiments will (2) assess the relevance of diabatic processes for the quality of predicting high-impact weather events and help pinpointing potential shortcomings in the representation of these processes in NWP models. Results from (1 and 2) will provide the basis for a virtual field experiment (3) that will test the design of flight strategies for the planned international field experiment T-NAWDEX. Within this experiment, diabatic processes will be observed in key areas for improving the prediction of North Atlantic / European weather systems.

• DFG Programme: Research Units
• Subproject of: FOR 896: Predictability and Dynamics of Weather Systems in the Atlantic-European Sector (PANDOWAE)
• International Connection: Switzerland