Dept. of Geosciences Colloquium: The role of moisture in the midlatitude atmospheric circulation

Zoom: https://tau-ac-il.zoom.us/j/82650086588

​Abstract:

The midlatitudes are characterized by high precipitation rates and high weather variability. The main features of this circulation include the midlatitude jet stream, which is a band of strong eastward winds, the storm tracks and the Ferrel circulation cell. The structure of the midlatitude circulation, which changes with time and in response to climate change, determines the patterns of temperature, precipitation and wind in the midlatitudes. The common conceptual picture of the zonal mean midlatitude atmospheric circulation is based on a dry theoretical framework, which neglects the effect of moisture. Under this assumption, the latitudes of the peak intensity of the jet stream, storm tracks and Ferrel cell are collocated. In this talk I will discuss how this conceptual picture is modified in the presence of strong latent heat release from moisture condensation in the midlatitude storm track. It will be shown that the poleward shift of the midlatitude jet in response to climate change is affected by the intensification and poleward shift of latent heating, in addition to the effect of the poleward shift of the storm tracks.

Event Organizers: Dr. Roy Barkan and Dr. Asaf Inbal