Is there a Pause in the Decline of Arctic Sea Ice Extent?

A couple papers were published this year about the recent "pause" in the decrease in September sea ice extent (SIE). One paper, Stern 2025[1] shows that the trend in Sept. SIE has been indistinguishable from 0 since about 2007. 

From Stern 2025

Likewise, England et al 2025[2] has found that 20-year trends have increased to the point where there is no longer a statistically significant downward trend for 2005-2024.

England et al 2025

The publication of these two studies, plus coverage of at least the latter in the Guardian, has caused quite a stir among contrarians on social media, who are claiming this is evidence that AGW isn't really a problem after all, and perhaps natural variability is what's driving recent changes in sea ice extent and temperature. However, that's not the way the authors of these studies are saying. Instead, the authors see the long-term downward trend in sea ice as being very real and caused by human activity, but they are also saying that we should not model this as a linear trend. Even on decadal time scales, natural variability can both add and subtract from the long-term trend to either amplify or dampen the trend temporarily, sometimes perhaps for 20 years or longer. Here's how this is stated in each paper. From Stern 2025:

Whatever the reason for the near‐zero trend during 2007–2024, Arctic SIE is predicted to continue declining due to increasing global average air temperature caused by anthropogenic greenhouse gas emissions. Based on global climate models, there is “high confidence that the Arctic Ocean will likely become practically sea ice free in the September mean for the first time ... before the year 2050” in all emissions scenarios (Fox‐Kemper et al., 2021).Thus, we would expect to see either a resumption of a steady decline in September SIE or a stepwise reduction (as in Holland et al. (2006)) through regime shifts facilitated by a younger and thinner ice pack that is more sensitive to external atmospheric forcing, whose decadal variability may also play a role.[1]

This is from England et al 2025:

Taken together, the wealth of available CMIP5 and CMIP6 simulations suggest it is possible that the present pause in sea ice decline may continue for a further 5–10 years, which would be consistent with timescales of Pacific ocean variability (Screen & Deser, 2019). If that were the case it may then imply the occurrence of an early ice-free Arctic is less likely than raw model output would suggest (Arthun et al., 2020; England & Polvani, 2023; Jahn et al., 2016, 2024; Wang et al., 2021). However, we find that the existence of this slowdown also predisposes the sea ice cover for a more rapid decline in the near future.[2]

So what might be going on here? A couple things should be noted. First, sea surface temperatures in the Arctic are still increasing pretty significantly, and clearly ice doesn't do well in warm water. This of course indicates that Arctic SSTs are spending more time at temperatures where we'd expect ice to melt.

Summer Arctic Sea Surface Temperatures

Secondly, even though September SIE has largely flattened since 2005/2007, it also spent several years well below the model mean, especially around 2007-2012. It seems that observations are actually returning to what models had predicted. In other words, models were not overpredicting the amount of summer arctic sea ice that would be lost by 2024.

IPCC SROCC Figure 3.3

And Sept SIE only one metric to consider. If we look at the volume and age of Arctic sea ice, we can see a bit more about what the continued warm temperatures are doing. Both maximum and minimum annual sea ice volume is continuing to decrease.

From Zack Labe

Consequently, Arctic sea ice is getting thinner and younger. In 2005, over 20% of Arctic sea ice was at least 4 years old. Now that percentage has dwindled to almost nothing.

NSIDC

In the Guardian article, Dr. Shepherd noted that “We know that the Arctic sea ice pack is also thinning, and so even if the area was not reducing, the volume still is. Our data show that since 2010 the average October thickness has fallen by 0.6 cm per year.” So while it's unquestionably good news that September Arctic SIE has roughly stabilized since 2005/2007, this is not an indication that the Arctic has stopped warming or that sea ice is not melting. It does indicate that natural variability plays a significant role in minimum sea ice extent, and the current slowdown has potentially increased our odds of keeping some Summer sea ice past 2050. However, eventually natural variability will add to the overall climate trend, and we'll likely see a return to rapid loss in September SIE in the Arctic.

And while the news perhaps is surprising, scientists have known that short-term pauses in loss of Summer SIE were plausible. One study from 2015[3] put the odds of a 20-year pause at about 5%. The model experiments in England's study increase these odds to about 20%. That's large enough that over the course of a century we'd expect something like this to happen.   

Swart et al 2015

So this is unquestionably good news, but unfortunately it's likely only temporary. At some point the trend will go downward again, and when natural variability adds to the trend, we're likely to see rapid declines in September sea ice extent. If England's study is correct, this will happen pretty soon, with simulations suggesting not more than 5-10 years from now. It seems to me this is the sea ice equivalent of ENSO. Contrarians frequently draw their GMST trendlines from El Niño years to La Niña years to create false impressions that global warming has "paused." Likewise with sea ice extent, "pauses" can occur while sea ice continues to get thinner and younger, so when natural variability turns against us again, there's less ice to resist the warming influence of AGW.

References:

[1] Stern, H. L. (2025). Regime shift in Arctic Ocean sea‐ice extent. Geophysical Research Letters, 52, e2024GL114546. https://doi.org/10.1029/2024GL114546
https://agupubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1029/2024GL114546

[2] England, M. R., Polvani, L. M., Screen, J., & Chan, A. C. (2025). Minimal Arctic sea ice loss in the last 20 years, consistent with internal climate variability. Geophysical Research Letters, 52, e2025GL116175. https://doi.org/10.1029/2025GL116175

[3] Swart, N., Fyfe, J., Hawkins, E. et al. Influence of internal variability on Arctic sea-ice trends. Nature Clim Change 5, 86–89 (2015). https://doi.org/10.1038/nclimate2483