October 2025
Update – 12/6/2025 – Data from PIOMAS is now available and updated through 30 November 2025. The last two months have set new monthly (October and November) record lows for Arctic sea-ice volume. I updated my Arctic dashboard below too.
Hi everyone! Instead of designing a new special feature visualization, this next ‘climate viz of the month‘ blog will focus on briefly summarizing the recent extremes in the Arctic. This may be a bit more provocative than my normal style, but I have been frustrated by how challenging it has become to get broader media coverage of some recent weather and climate extremes (like in the polar region). I have been posting near-real-time graphics of sea ice and other climate data on social media since the fall of 2016, and anecdotally (so take this with a grain of salt) the last few months are the first time that I can recall having difficulty generating more interest in these types of new data records. I acknowledge that I have the privilege of a large platform, and I am thankful for everyone who shares this work. However, it has become increasingly hard to reach beyond the climate-interested community lately. I am not proposing any hypothesis about why this is happening, and I am mostly using this blog as a small outlet to express that frustration. Maybe it is just a me problem! I also may be missing some of this coverage entirely. But we all need to vent once in a while…
Anyways, I wanted to highlight the recent records across the Arctic, including the exceptional warmth observed across the Arctic Circle in October. This is already a month that experiences strong warming due to Arctic amplification, and it is evident that the long-term trend continues to accelerate. The recent anomalous warmth was particularly pronounced near the North Pole and extended southward from the Canadian Arctic Archipelago toward the Barents, Kara, and Laptev Seas. In several areas, temperature anomalies exceeded 5°C above the 1981 to 2010 average. A number of daily temperature records were also set in early October across the northernmost latitudes (north of 80°N), driven in part by the poleward transport of heat and moisture from the North Atlantic Ocean.
It remains challenging to determine the exact direction of causality in these monthly mean maps. The relative warmth can suppress sea-ice formation along the outer ice edge, while the lack of sea ice can also enhance heat transfer from the open ocean to the atmosphere through turbulent heat fluxes. For instance, earlier this season we found record warm sea surface temperatures in the Kara Sea region in August. What is clear though is that sea-ice growth across the eastern half of the Arctic has been remarkably slow in recent weeks. Current sea-ice extent is at record low levels in regions such as the Barents Sea, as well as areas closer to Canada including Hudson Bay (almost no ice has formed yet) and Baffin Bay. Compared to any other year since at least 1979, the largest outlier this season is in Baffin Bay (located between Greenland and Ellesmere/Baffin Islands). So, it looks like it will be another December with a late ice freeze-up in these locations, which may affect the habitat for polar bear populations. This lack of ice in Canada can also moderate potential cold air outbreaks across eastern North America because the source region is relatively warmer, which is something to keep in mind for the longer-range outlooks. This is the time of year where a lot of people are tossing around winter outlooks for the United States, and in my view, it is crucial to take into account the background effects of our warming climate (due to the human emission of fossil fuels).
There has also been almost no southward expansion of the ice edge toward Svalbard and Franz Josef Land so far this season. My animation of daily sea-ice concentration shows this influence of local weather conditions here around the marginal ice zone. While some of the recent ice retreat is linked to persistent southerly winds and wave activity that tries to push the ice edge poleward, there may also be contributions from deeper ocean heat (e.g., Atlantification). But it is impossible to separate these influences in real time due to the lack of spatially and temporally complete observations. We certainly need greater support for sustained Arctic data monitoring, particularly through moorings and buoys, in order to better understand these changes.
As of late November 2025, total Arctic sea-ice extent (taking into account all basins) is a record low for this time of year. This is nearly 2 million square kilometers below the 1981-2010 average. The rapid changes in the Arctic will continue to produce wide-ranging impacts, and examining these local extremes provides critical insight into how this region is transforming.
The other side of the world has also observed some new climate records, including last month’s record warm October for the Antarctic Circle. Despite larger uncertainties in Southern Hemisphere data, multiple datasets now confirm this October record. I haven’t had the extra time to validate this statistic, but my sense is that it is quite unusual to have both poles set new temperature records at the same time. All in all, October 2025 was another very historic month for our climate.
Unfortunately, my Arctic climate dashboard remains unavailable. This is due to the recent pause in data from the near-real-time passive microwave satellite observations of Arctic sea-ice concentration. This gap is also preventing updates to Arctic sea-ice thickness and volume from PIOMAS, which appears to be connected to this same issue and the broader transition from SSMIS to AMSR2. I hope we receive an update soon, especially given the recent warmth across the Arctic and the already low average sea ice thickness observed in late summer. Until then, I am unable to update these visuals. It has been a very challenging year for maintaining, supporting, and developing these important climate datasets.
I hope everyone who celebrates Thanksgiving had a great one. As I mentioned earlier, I’m genuinely thankful for the opportunity to share climate science with such a broad audience – and even more thankful for your support along the way. Thank you for being here and keep telling these daily climate data stories.
You can always find my older blogs from this year at https://zacklabe.com/blog-archive-2025/ and the associated climate data rankings at https://zacklabe.com/archive-2025/. My Buy Me a Coffee account is also available at https://buymeacoffee.com/zacklabe.
Changes in mean surface air temperature anomalies (GISTEMPv4; 1951-1980 baseline), mean Arctic sea ice extent (NSIDC; Sea Ice Index v4), and mean Arctic sea ice volume (PIOMAS v2.1; Zhang and Rothrock, 2003) over the satellite era. Updated 12/6/2025.
Other Blogs (Monthly):
Other Climate Data Statistics (Monthly):
My Visualizations:
My research related to data visualization:
[2] Witt, J.K., Z.M. Labe, A.C. Warden, and B.A. Clegg (2023). Visualizing uncertainty in hurricane forecasts with animated risk trajectories. Weather, Climate, and Society, DOI:10.1175/WCAS-D-21-0173.1
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[1] Witt, J.K., Z.M. Labe, and B.A. Clegg (2022). Comparisons of perceptions of risk for visualizations using animated risk trajectories versus cones of uncertainty. Proceedings of the Human Factors and Ergonomics Society Annual Meeting, DOI:10.1177/1071181322661308
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[Plain Language Summary][CNN]
The views presented here only reflect my own. These figures may be freely distributed (with credit). Information about the data can be found on my references page and methods page.