Last week, record-breaking heatwaves hit the north and south poles. Parts of Antarctica were 70+ degrees Fahrenheit warmer than average, and parts of the Arctic warmed 50+ degrees Fahrenheit over average temperatures. This event is particularly concerning because the occurrence of melting in both poles is rarely simultaneous.

“They are opposite seasons. You don’t see the north and the south [poles] both melting at the same time,” said Walt Meier, Senior Research Scientist, National Snow and Ice Data Center. “It’s definitely an unusual occurrence.”

Why This Matters

The Arctic and Antarctica are two regions hit the hardest by global warming. The Arctic has been warming two to three times faster than the rest of the earth, resulting in massive changes to the area’s topography, including giant sinkholes forming in its ocean.

As for the heatwave in Antarctica, Meier believes it is likely a freak occurrence due to “a big atmospheric river” bringing warm, moist air from the Pacific southward. But these unseasonably warm temperatures don’t bode well, especially after Antarctic ice shelf Larsen-B suddenly collapsed. In late February, Antarctica set a record for the lowest summer sea ice at 741,000 square miles.

"[H]eatwaves at the poles are a strong signal of the damage humanity is wreaking on the climate,” writes Fiona Harvey for the Guardian, “and the melting could also trigger further cascading changes that will accelerate climate breakdown.

Record-Breaking Temperatures

On Friday, the world as a whole was only 1.1 degrees F above average temperatures recorded from 1979-2000. Meanwhile, the Arctic was 6 degrees F warmer, and Antarctica was about 8.6 degrees warmer. The Vostok Station in Antarctica observed some of the most dramatic temperature changes -- hitting zero degrees F, a record-breaking 27 degrees higher than average since data collection began 65 years ago.

“In about 65 record years in Vostok, between March and October, values above -30°C (-86 degrees Fahrenheit) were never observed,” said Stefano Di Battista, a researcher of Antarctic climate studies.