Every year, the Arctic freezes. The sea ice of the Arctic reaches its maximum extent every year in March, and then as the season changes to spring, it begins to melt to its minimum about six months later. For 47 years, satellites have collected data to create a record of how Arctic sea ice grows and shrinks seasonally.
This year, the maximum extent of the ice in the Arctic was the lowest it's ever been since record-keeping began. It reached around 5.53 million square miles (14.33 million square kilometers) on March 22, 2025, which is around 30,000 square miles (80,000 square kilometers) fewer than the previous lowest extent, which happened in 2017.
Like the rest of the planet, the Arctic is known to be getting warmer due to human caused climate change. But those changes are happening three to four times as fast in the Arctic compared to other regions, in a phenomenon known as Arctic amplification.
This accelerated warming is likely due to a variety of factors, including increases in sea surface temperatures, reductions in cloud cover, and shifts in the transport of heat in the ocean, for some examples.
A warmer Arctic also means that there is a reduction in the difference in barometric pressure between upper and mid-latitudes, which ultimately weakens the jet stream. The jet stream is a narrow strip of very strong winds in the atmosphere; these winds blow at about 30,000 feet (9,100 meters) from west to east. A weaker jet stream allows colder Arctic temperatures to go much lower than they normally would. And since the jet stream moves weather systems, as it weakens those systems can get stuck.
"The warming winter atmosphere above the Arctic Circle does impact large-scale weather patterns that do influence for those of us outside the Arctic," Julienne Stroeve, an ice scientist at the University of Manitoba, explained to The Associated Press.
The five lowest Arctic winter sea ice extents in have all happened since 2015.
Meanwhile in Antarctica, there was nearly a record low extent after it underwent its summer melt period, but it didn't quite break the record. Instead, Antarctica's sea ice was at its second lowest summer extent this year.
Sources: The Associated Press, National Snow and Ice Data Center
