Arctic sea ice experienced an unprecedented winter buildup, recording its lowest extent in 47 years, scientists reported on Thursday. This concerning development, a direct result of climate change, is likely to have global consequences.
The Arctic typically reaches its maximum sea ice coverage in March, marking the start of a six-month melting phase. However, this year’s peak, recorded on Saturday by the National Snow and Ice Data Center, reached only 5.53 million square miles (14.33 million square kilometers). This is roughly 30,000 square miles (80,000 square kilometers) smaller than the previous low peak observed in 2017, an area roughly equivalent to the size of California.
“Warming temperatures are the primary cause for the reduction in sea ice,” explained Walt Meier, an ice data specialist. “Sea ice is particularly sensitive to temperature; at 31 degrees, it supports ice skating, while at 33 degrees, it’s suitable for swimming.”
Jennifer Francis, a researcher at the Woodwell Climate Research Center in Cape Cod, underscored this alarming situation, describing it as another resounding alarm in climate records being broken. “The vanishing sea ice serves as an early warning indicator, signaling various subtle climate changes,” Francis highlighted.
Experts pointed out that the rapid warming in the Arctic, occurring at four times the rate of the rest of the world, influences weather patterns globally. The diminishing pressure and temperature differences between northern and southern regions weaken the jet stream, causing it to dip southward, resulting in prolonged cold outbreaks and stagnant storm systems that can lead to more rain or snow, according to Francis and the National Snow and Ice Data Center.
Julienne Stroeve, an ice scientist at the University of Manitoba, remarked on the impact of a warmer Arctic atmosphere on larger weather systems outside the Arctic zone. She also emphasized that the current thinning of sea ice could lead to further rapid melting during the summer. Although a record low was reached this winter, it doesn’t necessarily guarantee a record low in the summer.
The decline in Arctic sea ice, especially prominent in summer months, continues to threaten the polar bear population—making them weaker and more food-insecure, as they depend on the ice for hunting. Additionally, the winter sea ice holds significant importance for marine life, including seal pups, and the fishing industry, Meier noted.
Back in 1979, the Arctic sea ice was recorded at a substantial 6.42 million square miles (16.64 million square kilometers). Since then, satellite observations show that the winter peak has contracted significantly—shrinking by an area equivalent to Pakistan. During robust winter ice years, the ice could stretch further toward the equator, impacting regions such as Japan, China, and the Gulf of St. Lawrence in Canada.
Meier stated that the sea ice has been receding across all four seasons, yet the summer holds critical importance for the Arctic ice’s overall health. Ice-free summer waters absorb heat rapidly, retain more energy, and subsequently contribute to milder and weaker conditions in fall and winter.
Notably, the five smallest winter peak records for Arctic sea ice have all occurred since 2015. Meanwhile, in Antarctica, a recent evaluation showed that the region came close to its minimum sea ice record but settled for the second-lowest level recorded. Even though the Antarctic generally hosts more sea ice with its own seasonal timing, globally combining both Arctic and Antarctic levels, sea ice reached a historical low this February.