The Arctic Ocean’s sea ice reached its 2025 summer minimum on September 10 without setting a new record low, a finding that at first glance appears to be a positive development. While the extent of sea ice has not plummeted below the 2012 record, scientists are warning that this recent slowdown is likely just a temporary reprieve from the relentless long-term trend of ice loss driven by human-caused climate change.
A 20-Year Slowdown in Ice Loss
After a record low winter maximum in March 2025, the Arctic seemed poised for a historic melt season. However, according to the U.S. National Snow and Ice Data Center (NSIDC), this year’s minimum extent of 4.602 million square kilometers ranks as the 11th lowest on record, far from the 2012 low. The current sea ice extent, while still significantly less than it was 50 years ago, has shown a statistically insignificant decline since 2005.
A new study in the journal Geophysical Research Letters explains this counterintuitive trend. It reveals that over the past two decades, natural variability in oceanic and atmospheric systems has acted as a counterweight to accumulating heat, temporarily slowing the rate of sea ice loss.
“If you had just drawn a straight line, you’d have been pretty wrong,” said climate scientist Mark England, who led the study. The research suggests that without the influence of human emissions, the period from 2005 to 2024 may have even seen substantial sea ice growth.
Concerns Despite the Slowdown
Despite the pause in minimum extent decline, experts stress that the overall picture remains dire. Sea ice volume and the amount of multiyear ice older, thicker ice that is crucial for the ecosystem have both plummeted to the lowest levels on record. Scientists caution that this temporary reprieve cannot last forever; models show a low chance of the slowdown persisting for another decade, after which a period of rapid ice loss is still expected to lead to ice-free Arctic summers before 2050.
In a separate but related development, the NSIDC was forced to make an unprecedented change in its data source for the first time in 38 years. After losing access to key data from a U.S. military satellite, the center has now switched to using a Japanese satellite. This crucial data is used not only for climate and weather models but also to help track the movements of polar bears and other wildlife that depend on the ice for survival.