Dept. of Geophysics Colloquium: The importance of dry intrusions for air-sea interaction and associated weather extremes

Zoom: https://tau-ac-il.zoom.us/j/85032703038

Abstract:

Dry intrusion (DI) air streams bring anomalously cold, dry, high-momentum air to the ocean surface, inducing intense air-sea interaction. The DIs comprise the cold and dry sector of extratropical cyclones, where air parcels descend slantwise from the midlatitude upper troposphere towards the surface in lower latitudes, where the airstreams typically fan out behind the cyclone’s trailing cold front. In this talk I will review recent results based on a Lagrangian-based identification of DIs using representative case studies and longer-term climatologies, allowing the quantification of the intrusions’ occurrence frequencies and strong association with enhanced air-sea interaction. Focus will be given to the Mistral hotspot in the Mediterranean, the Indian Summer Monsoon and the North Atlantic Ocean, with global implications. The key role of DIs in triggering intense air-sea interaction in the form of turbulent ocean heat and moisture loss provides new process-based insight on the DIs link to extreme weather events. Thus, DIs are not only directly related to strong winds and extreme cold temperatures but also to heavy precipitation ahead of the dry air. The importance of this link motivated the airborne field campaign NAWDIC, and extends from the midlatitudes to subtropical and tropical regions, opening new research avenues.

Event Organizer: Dr. Lior Rubanenko