Antarctic base station experiences warmest August on record amid blizzard run


Updated

October 13, 2018 11:55:07

Antarctica is known for its weather extremes, and even with temperatures remaining well below freezing, Mawson Station has experienced its warmest August on record.

The mean temperature was about 6 degrees Celsius above the long-term average for August, and recordings on the station date back more than 60 years.

Temperatures were still sub-zero all month, and the highest mean daily maximum temperature was -10.2C.

Mawson’s August mean temperature of -12.8C was the highest on record and was 5.8C above the long-term average, and 1.2C above the previous record from 1996.

Scott Carpentier, the manager of Antarctic meteorology with the Bureau of Meteorology (BOM), said it was also an “exceptionally warm” August at Davis Station, where the highest mean daily maximum temperature hit -9.6C.

“They were a good five degrees above the long-term averages there,” he said.

“We haven’t seen warm temperatures like this in August since 1998.”

Mr Carpentier said the higher temperatures were a result of warm air masses coming off the Southern Ocean.

“There was this large wave of energy that got thrown up in the tropics, it propagated all the way down to the Antarctic coastline and pushed a whole bunch of air from the warmer Southern Ocean right across and into the continent,” he said.

Mr Carpentier said it was a blip rather than an indication of a long-term change.

“The following month, September, we saw all three stations — Davis, Mawson and Casey — are all below their September averages for temperatures,” he said.

The meteorologist said climate change was having a cooling impact on Antarctica, unlike the warming being experienced in the tropics.

“We’re seeing fewer of these warm air intrusions move into the Antarctic, so we’ve actually been witnessing just a slight cooling trend over that part of Antarctica for the last 40 years,” he said.

Windy day record broken

Esther Rodewald has been the station manager at Mawson Station since Christmas Eve last year.

She said she did not notice the warmer August temperatures because she and her fellow expeditioners spent most of their time indoors sheltering from extreme winds.

“We had 14 blizz [blizzard] days that month, including eight in a row,” she said.

“We also broke the all-time wind run record, so when it’s windy it’s just cold and you can’t really tell the difference if it’s a couple of degrees warmer.”

Ms Rodewald said for more than a week winds were blowing more than 110 kilometres per hour and visibility was limited.

“There is no outside work, no outside activity,” she said.

“It’s pretty horrendous out there — you can barely see your own feet in those conditions.”

She said expeditioners at Mawson were now enjoying more daylight hours.

“It’s an absolutely stunning place, so it’s beautiful to be here and be able to look out the window and see the landscape all the time,” she said.

Topics:

weather,

science-and-technology,

research,

tas,

antarctica

First posted

October 13, 2018 11:46:44



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