https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL116175
Minimal Arctic Sea Ice Loss in the Last 20 Years, Consistent With Internal Climate Variability
Abstract
Over the past two decades, Arctic sea ice loss has slowed considerably, with no statistically significant decline in September sea ice area since 2005. This pause is robust across observational data sets, metrics, and seasons. Large-ensemble CMIP5 and CMIP6 simulations reveal that such periods with minimal sea ice decline under increasing greenhouse gas emissions are not unusual. Analysis of ensemble members that simulate analogs of the observed pause indicates that the current slowdown could plausibly persist another five to 10 years, although the chances of a faster-than-average decline are increased in the near-future. The modeling evidence suggests that internal variability has substantially offset anthropogenically forced sea ice loss in recent decades. Overall, this observed pause in Arctic sea ice decline is consistent with simulated internal variability superimposed on the long-term trend according to the bulk of the climate modeling evidence.
Plain Language Summary
Over the last 20 years, the decline of Arctic sea ice has slowed down substantially. Climate models (from CMIP5 and CMIP6) show that pauses in sea ice loss across multiple decades can happen, even as greenhouse gas emissions continue to rise. When we compare the current slowdown to similar pauses in model simulations, we see that it could plausibly continue for another five to 10 years, although the same slowdown makes a faster-than-average sea ice decline more likely in the coming years. Most of the evidence from these climate models suggests that natural climate variations have played a large part in slowing the human-driven loss of sea ice. However, it is not entirely certain whether changes in the human influence on climate (the “forced response”) have also contributed. Overall, while it may sound surprising that Arctic sea ice loss has slowed down even as global temperatures hit record highs, the climate modeling evidence suggests we should expect periods like this to occur somewhat frequently.
Key Points
- The loss of Arctic sea ice cover has undergone a pronounced slowdown over the past two decades, across all months of the year
- Rather than being an unexpected rare event, comprehensive climate models from CMIP5 and CMIP6 simulate such pauses relatively frequently
- According to these climate model simulations, this pause in the loss of Arctic sea ice could plausibly continue for the next 5–10 years
