Stratospheric-tropospheric mass exchange during the Presidents' Day storm

Abstract

Using a quasi-Lagrangian transport model, stratosphere-tropospheric mass exchange is estimated for the region including and immediately adjacent to the tropopause depression. The estimated mass transport from the stratosphere to the troposphere for the 24-h period is 5 × 1014 kg. The transport from the troposphere to the stratosphere is 2 × 1014 kg yielding a net transport across the tropopause of 3 × 10-14 kg from the stratosphere to the troposphere. The mass transport from stratosphere to troposphere across the 3.0-IPV surface coincides with descending air, often referred to as the "dry airstream,' arcing counterclockwise around the polar-front jet and trough system from northwest to east. Reverse transport from the troposphere to the stratosphere occurs northeast of the depression and agrees with trajectories of air parcels within the end region of rising "conveyer belts'. -from Authors