RESUMO
Global mean lower stratosphere temperatures rose abruptly in January 2020 reaching values not experienced since the early 1990s. Anomalously high lower stratospheric temperatures were recorded for 4 months at highly statistically significant levels. Here, we use a combination of satellite and surface-based remote sensing observations to derive a time-series of stratospheric biomass burning aerosol optical depths originating from intense SouthEastern Australian wildfires and use these aerosol optical depths in a state-of-the-art climate model. We show that the S.E. Australian wildfires are the cause of this lower stratospheric warming. We also investigate the radiatively-driven dynamical response to the observed stratospheric ozone perturbation and find a significant strengthening of the springtime Antarctic polar vortex suggesting that biomass burning aerosols play a significant role in the observed anomalous longevity of the ozone hole in 2020.
