Stratospheric Australian fire smoke layers over Punta Arenas, Chile, measured by ground-based lidar and AEOLUS

Exceptionally strong wildfire activity in Australia in summer 2019-2020 triggered the evolution of pyrocumulonimbus clouds, releasing enormous amounts of fire smoke into the upper troposphere and lower stratosphere region of the usually very clean southern hemisphere. Measurements at the lidar site of Punta Arenas (53°S), Chile, show that the first stratospheric smoke layers arrived over Punta Arenas at 6 Jan 2020.

First results show striking similarities to a record-breaking event of stratospheric smoke layers from wildfires in Canada in 2017 (Baars et al., ACP 2019). At Punta Arenas, lidar ratios reach values of 45-50 sr at 355 nm, and 60-65 sr at 532 nm wavelength. Particle linear depolarization ratios reach values of 19% at 355 nm, and 15% at 532 nm wavelength.

Aeolus is able to detect these intense layers of stratospheric smoke in the southern hemisphere as well. In this contribution, we will discuss our findings of extensive and intensive smoke optical properties over Punta Arenas to the related Aeolus aerosol spin off products of nearby overpasses. Especially the particle linear depolarization ratio at 355 nm are of relevance as AEOLUS is only able to measure the co-polarized 355 nm signal.