The reading was taken by Argentina's National Meteorological Service at the country's Esperanza research station, AFP reported. The thermometer climbed to 18.3 degrees Celsius (approximately 64.9 degrees Fahrenheit) around noon on Thursday, beating Antarctica's previous record, set in 2015, by 0.8 degrees Celsius.

"The reading is impressive as it's only five years since the previous record was set and this is almost one degree centigrade higher," Victoria University of Wellington climate scientist James Renwick, who has verified previous Antarctic records for the World Meteorological Organization (WMO), told The Guardian. "It's a sign of the warming that has been happening there that's much faster than the global average."

The Esperanza station is located on the Antarctic peninsula that juts out towards South America. Heating at a rate of around three degrees Celsius over the past 50 years, the peninsula is one of the fastest warming places on Earth.

Australian National University climate scientist Nerilie Abram, who has worked on the peninsula's James Ross Island, told The Guardian that it sometimes gets warm enough to wear a t-shirt.

"It's an area that's warming very quickly," she said.

The Esperanza station boasts one of the longest-running temperature records on all of Antarctica, dating back to 1961. Renwick said the reading would have to be verified, but that the station was generally trustworthy. He also said the particular high reading was probably a combination of the climate crisis and local weather patterns, as strong northwestern winds blow down the mountains, bringing warmer temperatures.

Argentina also reported another record breaking temperature Thursday at its Marambio base, also on the peninsula, which saw its hottest February day since 1971. That base reached a temperature of 14.1 degrees Celsius (approximately 57.4 degrees Fahrenheit), breaking its Feb. 24, 2013 record of 13.8 degrees Celsius (approximately 56.8 degrees Fahrenheit).

The previous record-high temperature for the Antarctic continent was also recorded at the Esperanza base, according to WMO. On March 24, 2015, the base reported a reading of 17.5 degrees Celsius (approximately 63.5 degrees Fahrenheit).

"To have a new record set that quickly is surprising but who knows how long that will last?" Renwick told The Guardian. "Possibly not that long at all."

The news comes as the European Union's Copernicus Climate Change Service declared this past January the warmest January on record.

Parts of Antarctica were among the regions that saw temperatures "much above average" for the month, the service said.

This was also the fourth January in a row in which the service recorded a below average sea ice extent in Antarctica. At 4.6 million kilometers squared (approximately 1.8 million square miles), it was around 17 percent below the 1981 to 2010 average.