Exploring the Links between Mid-Latitude Large-Scale circulation and Indian Summer Monsoon Onset and Progression

Abstract: The onset and progression of Indian summer monsoon exhibit substantial year-to-year variability, affecting the associated precipitation and potentially leading to severe societal impacts. While tropical modes of variability are known factors influencing the evolution of the monsoon, evidence indicates that its unsteady progression can also be accompanied by a change in the strength and reach of a descending mid-tropospheric flow that brings dry air towards the Indian subcontinent from northwestern quadrants. In this work we illustrate our exploration of the link between specific patterns of the upper-level large-scale circulation over Eurasia (e.g., the presence of blocking anticyclones over western Russia) and the onset and progression of the Indian monsoon, highlighting the mediating role of the northwesterly dry air intrusion.

Biography: Ambrogio Volonté is a Senior Research Fellow at NCAS / University of Reading.

He is currently taking part in projects focusing on:

- Dynamics and sea-ice interaction of Arctic summer cyclones (a project that included an aircraft field campaign);

- Dynamical and climatological properties of sting-jet cyclones;

- The role of diabatic processes and air-sea interaction in the dynamics of Mediterranean cyclones;

- Mid-latitude controls on Indian monsoon onset and progression, with particular focus on kinematics and dynamics of the intrusion of mid-latitude dry air.

His research interests go from mesoscale airflows and synoptic-scale extratropical cyclones up to the dynamics of larger systems such as monsoons, as he is interested in process-based and Lagrangian analysis of all sorts of weather features.