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Antarctica may have set its highest temperature ever recorded Tuesday

Antarctic Peninsula, where possible record high temperature was set Tuesday, March 24, 2015. (NASA)

Need another indicator of climate warming in Antarctica? The trio of weather bloggers at Weather Underground report the temperature there likely hit a record-breaking 63.5F (17.5C) Tuesday.

The balmy reading was logged at Argentina’s Esperanza Base, which lies on the northern tip of the Antarctic Peninsula.

Weather Underground bloggers Jeff Masters and Bob Henson write Tuesday’s 63.5F reading bests the previous record mark of 63.3F set just the day before [March 23] at Argentina’s Marambio Base (a small islet off the Antarctic Peninsula) and a prior reading of 62.8F (also from Esperanza Base) from April 24, 1961.

Tuesday’s new record is not yet official. Argentina’s Esperanza Base, the site of the record, may not be considered part of Antarctica for the purposes of weather records according to Weather Underground historian Christopher Burt. He explains four different ways Antarctica can be defined in a blog post.  Ultimately, for the record to be official, the World Meteorological Organization will need to validate the temperature reading and determine it is, in fact, Antarctic.

Irrespective of whether the record stands, it fits right into the pattern of rapid climate warming recently observed in the Antarctic Peninsula region. The British Antarctic Survey writes this region has warmed about 5F (2.8 C) in the last 50 years. “[This] makes this the most rapidly warming region in the Southern Hemisphere – comparable to rapidly warming regions of the Arctic,” it notes.

Not only are temperatures rising on its Peninsula, but multiple studies this past year have also documented a loss of ice along Antarctica’s coasts and within its interior, as The Post’s Sarah Kaplan writes today:

How bad is Antarctic ice loss? Let scientists count the ways. In December, researchers reported that West Antarctica, one of the world’s most unstable ice sheets, is collapsing faster than anyone had predicted and contributing to rapid sea level rise. Earlier this month, the same was found to be true of Totten Glacier in East Antarctica.
This week, glaciologists report the massive floating ice shelves that form a fringe along the continent’s coastline are also deteriorating.

This week’s possible temperature record was setup by a large, warm ridge of high pressure – or heat dome – originating from southern South America that extended over the Antarctic Peninsula. The intensity of this weather system was almost off-the-charts, judging by the purple shades on the map below, portraying the difference from normal conditions:

Here’s another view of this heat dome – from a global perspective  – which shows this particular high pressure ridge was, by far, the strongest in the world compared to normal:

Should the high temperature at Argentina’s Esperanza Base be validated as a record, Antarctica will join Greenland in this achievement over the last two years. On July 30, 2013, the observing station Maniitsoq / Sugar Loaf on Greenland’s southwest coast soared to 78.6F, which was a record according to the Danish Meteorological Institute.

Correction, 9:26 p.m.: An earlier version of this posted wrongly stated a previous Antarctic record high temperature was 62.6F from October 1976 whereas it was actually 62.8F from April 24, 1961.