Gourav Mitra (IAP) Planetary-Scale and Mesoscale Dynamics in the Middle Atmosphere

Gourav Mitra (IAP) will deliver a talk on the topic "Planetary-Scale and Mesoscale Dynamics in the Middle Atmosphere".

Abstract:

This talk is divided into two parts. In the first part, I will focus on planetary-scale wave dynamics, i.e., tides and planetary waves with horizontal wavelengths of several thousand kilometers and their behavior during Sudden Stratospheric Warming (SSW) events. These results come from my PhD research, which combines traditional monostatic specular meteor radar (SMR) wind observation with reanalysis data. I will present case studies highlighting low-latitude planetary-wave variability and multistep nonlinear interactions between planetary-scale waves during SSW events.

In the second part of the talk, I will introduce my ongoing work at IAP on mesoscale dynamics, characterized by temporal scales shorter than the inertial period and spatial scales of a few tens to a few hundreds of kilometers. I will describe our approach for estimating the vertical flux of horizontal momentum associated with mesoscale fluctuations, utilizing state-of-the-art HYPER (Hydrodynamic Pointwise Environment Reconstructor) 4D wind fields derived from multistatic SMR observations.