Looking for snow... in the sky and on the glaciers
It may sound weird but we are in Antarctica and there is no snow.. While common on the South Shetland Islands north of the Antarctic Peninsula (we are only 62ºS) to have temperatures above zero in summer, there is a tendency over the last 50 years of warmer temperatures and more melt. Yes, there was a short pause of warming at the Peninsula in the beginning of 21st century due to nature climate variability but after this period the warming trend came back even stronger. And there are more frequent, stronger and longer lasting extreme warm events. Our study of atmospheric rivers includes their impact on warm temperatures and surface snow melt in the Antarctic Peninsula. And they also tend to bring a lot of rainfall instead of snowfall as temperatures here are already close to 0ºC.
One year ago, on 7-8 February 2022 several northern Antarctic Peninsula stations, including King Sejong where we are now, showed new record high temperatures. There was a lot of melt all over the Peninsula, including over its ice shelves. Antarctic sea ice concentration reached record low. This year Antarctic sea ice extend sets a new record low. Also we are approaching the end of this year melt season and what we have seen this week visiting the nearby glaciers – there is a lot of melt.
This week on King George Island has been very busy. We collected surface snow samples from the nearby Fourcade glacier. Which was not really nearby and the whole trip took us 6 hours with a difficult approach jumping on different size of volcanic rocks and crossing the streams of melt water from the glacier.
Photo: The way from King Sejong station to the Fourcade glacier crossing a stream. 12 February 2023. ©Irina Gorodetskaya
Photo: Sampling surface snow for stable water isotope analysis at the edge of the Fourcade glacier. 12 February 2023. ©Irina Gorodetskaya
We continued monitoring precipitation with MRR-PRO radar and launching radiosondes together with the cloud sensor to measure the amount of supercooled liquid water in clouds. And collecting precipitation samples on the roof of the meteorological platform to analyse what is inside rain or snowfall water. There is no strong rain here – only drizzle. And we collect precipitation directly falling from the sky using a funnel installed on top of a plastic tube.
Photo: Sampling snowfall and rainfall on the roof of meteorological platform at King Sejong.
On 16 February we had another window of good weather. There was a high-pressure ridge over the Antarctic Peninsula and an atmospheric river bringing lots of heat and moisture with intense snowfall west of us – over the West Antarctic ice sheet coast. This gave us an opportunity to measure the upstream conditions of this atmospheric river (and hey.. launching radiosondes in good weather is way better than in gale winds.:). And also to go to the Collins glacier, where we sampled snow.
Photo: Collins glacier. 16 February 2023. ©Irina Gorodetskaya
Photo: Sampling surface snow and digging a snow pit on Collins glacier. 16 February 2023.
Photo: Finishing sampling and radio communication with the base before descending (Claudio, Sangjong and Irina).
Returning on Zodiac boat in the afternoon:
Photo: Departing from Collins glacier. ©Irina Gorodetskaya
When you enter the station – always remember to change from your outdoor shoes to slippers. No exceptions... But here you can also choose your style...
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