Speaker
Description
In March 2022 and July 2024, tropospheric heat waves with temperatures up to 39°C above average struck large regions of Antarctica and caused decreasing sea ice levels and, for example, a collapsing ice shelf. Both events have been – at least partly – attributed to climate change, but the proximate causes of the heat waves can be different. While the 2022 event has been associated with a La Nina event, a sudden stratospheric warming (SSW) event due to atmospheric wave activity is likely the origin of the 2024 heat wave. SSW events in the Northern Hemisphere are relatively common (roughly every two years) and known to cause anomalies in infrasound detections at high to mid latitudes. In the Southern Hemisphere, SSW are extremely rare – a major warming occurred in 2002 and a minor warming was observed in September 2019.
We analyse multiyear observations of the International Monitoring System infrasound stations in and around Antarctica for potential impacts of the recent heat waves and SSW events on infrasound detections and detection parameters. We focus on the quasi-continuous microbaroms and utilize source models, atmospheric models and propagation simulations for further investigating identified detection anomalies.
| [email protected] |
