Expedition report of our colleagues at the station

During the austral summer season 2023-2024, two colleagues from Université Libre de Bruxelles (ULB), Sibylle Boxho, and from Ghent University (UGent), Paula Lamprea, will undertake an expedition to the Princess Elisabeth station (PEA) as part of the PASPARTOUT project. This project, financed by the Belgian Science Policy Office (BELSPO), aims to gain an in-depth understanding of the links between atmospheric circulation patterns, weather regimes, particles, volatile organic compounds (VOCs) and moisture, along with their implications and changes within a changing global climate. Follow this link, to their stories about their activities in Antarctica.

and again a new season at PEA

 Since a bit more than a week, Princess Elisabeth station is open again. The first team around Alain Hubert arrived and has been busy with putting back the station in operational mode for summer season. On the website of the station you can follow the general activities. 

Last week, the first radio soundings with weather balloons have been done again. See the first image below. The jet stream in the upper troposphere was particularly strong (almost 60 m/s) and wind peaked in the stratosphere around 26 km altitude again. It means that the polar vortex was situated above the region of PEA. This year, the ozone hole over Antarctica seems to last again longer than usual (see here).  Since last week, the station team set up again our ozone spectrophotometer which measures UV radiation and the total atmospheric ozone column. From the second graph below, you can see that the UV index reached around local noon bit above 11, meaning that non-protected skin get hurt within 10-15 minutes. This is a direct effect of the reduced total ozone (around 160 DU) due to the ozone hole. 

This season we will also be back at the station with two people from our PASPARTOUT project. We will keep you updated on this blog of the related activities. 

Short clip of our activities at the station

We made a short clip showing our instruments and activities at the Princess Elisabeth station. The clip can be viewed here:

It can also be found on Instagram, Twitter and Facebook:

• Facebook NL: https://www.facebook.com/watch?v=1117580542248687
  
• Facebook FR: https://www.facebook.com/www.meteo.be/videos/1310064126242606/
  
• Instagram: https://www.instagram.com/p/Comhfv5suW6/
  
• Twitter NL: https://twitter.com/meteobenl/status/1625103540346662913
  
• Twitter FR: https://twitter.com/meteobefr/status/1625103931608104960

Season 2022 - 2023 at Princess Elisabeth has started

The austral season at Princess Elisabeth has started since a few days. It will mainly be a maintenance season and no personnel from our science projects will be there this time. The team at the station will nevertheless take care of our instrumentation. In particular of interest will be how the instruments at the remote site in the mountains have survived - far away from the station and thus only powered by a small wind turbine, a solar panel and some batteries. We will keep you posted on it. 

In the meantime, there has been the first radio sounding of this season on 30 November 2022. On the plot below you can see the high wind in the stratosphere above 20 km height, indicating that the polar vortex was situated above the station. This time the ozone hole is not exceptional (see also the copernicus monitoring). However, still large enough for low total ozone at this time and therefore elevated uv radiation. This caused extreme uv conditions with the UV index rising around local noon above 10, see image below.

season's first radio sounding on 30 November 2022

UV index on 1 December 2022; with extreme values around local noon

Tonga volcano eruption pressure wave visible in our recordings

On Saturday 15 January, a volcano erupted near Tonga, with devastating effects. The immense eruption catapulted ash, particles and gases apparently deep into the stratosphere, with estimates up to 30 km height. Besides the disastrous impact on humans, the environment, infrastructure, the eruption sent also a pressure wave around the world, detectable by measurements of atmospheric pressure (e.g., in Belgium). We can even detect this signal in the recordings of the atmospheric pressure inside our nephelometer, running at Princess Elisabeth station - see image below. The eruption took place around 4am UTC (or 5pm local time Tonga). The pressure wave took around 9 hours (for the around 17000 km to the station. A first variation of the pressure of about 2 hPa was detected at 13 UT and a second one of about 1hPa at 15 UT (one wave took the one way around the globe, the other one the other way round).  

Andy and Preben arrived at the station

 After ten days of quarantine in Cape Town, Andy and Preben landed in the evening of 9 December at Perseus air strip, around 60 km from Princess Elisabeth station. After unloading and the trip to the station, they arrived in the very early morning hours at the station. They already checked a lot of our instrumentation. You can follow their activities on our project web page.

Inside the polar vortex

 Since Friday 19 November, the team at PEA is launching every second day a weather balloon with a radiosonde for measuring the vertical profile of temperature, relative humidity, wind and pressure. At the moment, the Antarctic ozone hole has started to be 'filled up' again.  However, yesterday's radio sounding happened inside the Antarctic polar vortex, with very high wind speeds between 15 and 20 km altitude, strong westerly winds and low temperature - as can be seen on the graph below (note however, that the humidity values above around 10 km are only indicative).  Total ozone was also very low respectively, with values between 150 and 200 DU.