The above image also shows that Antarctic sea ice reached a record low area of 1.09 million km² on February 24, 2023, close to a Blue Ocean Event and deviation of -2.86σ.
Low global sea ice means that less sunlight gets reflected back into space and instead gets absorbed by the sea surface, resulting in high sea surface temperatures at both poles. The image below shows that the global sea ice area was 3.31 million km² lower than 1981-2010 on October 24, 2025, a deviation from 1981-2010 of -5.25σ.
Low sea ice and polar amplification of the temperature rise contribute to high air temperatures at both poles. The image below shows the September 2025 temperature anomaly compared to 1951-1980.
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| [ from earlier post ] |
At this time of year, little sunlight is reaching the South Pole yet, so temperatures over Antarctica are still well below zero °C. Nevertheless, Antarctic temperature anomalies were high in September 2025 (see the above image) and the Antarctic temperature anomaly recently was as high as +4.22°C compared to 1979-2000 (on October 14, 2025).
The record low Antarctic sea ice area and the high temperatures over Antarctica are remarkable given the absence of El Niño conditions. Record high daily temperatures over Antarctica were reached on each consecutive day of the week from 12 through 18 October 2025, as illustrated by the image below. The inset shows high polar temperature anomalies versus 1991-2000 on October 18, 2025.
The record low Antarctic sea ice area and the high temperatures over Antarctica are remarkable given the absence of El Niño conditions. Record high daily temperatures over Antarctica were reached on each consecutive day of the week from 12 through 18 October 2025, as illustrated by the image below. The inset shows high polar temperature anomalies versus 1991-2000 on October 18, 2025.
High temperature anomalies at the poles occurred on October 25, 2025, as illustrated by the image below.
High temperatures come with Jet Stream distortion on October 25, 2025, as illustrated by the image below that shows the Jet Stream (at 500 hPa) moving deep over Antarctica.
This came with high precipitable water anomalies over Antarctica, as illustrated by the image below.
The danger has been discussed in earlier posts such as this one. The increased snowfall thickens the snow on Antarctica with only little freshwater returning to the ocean. As a result, the Southern Ocean surface is getting more salty, and as also discussed in an earlier post, saltier surface waters sink more readily, allowing heat from the deep to rise, which can melt Antarctic sea ice from below, even during winter, making it harder for ice to reform. This vertical circulation also draws up more salt from deeper layers, reinforcing the cycle.
This leads to a loss of sea ice (and thus loss of albedo and latent heat buffer), as well as less heat getting transferred from the atmosphere into the Southern ocean, while more heat can be transferred from the Southern Ocean to the atmosphere.
Arctic sea ice volume
Meanwhile, Arctic sea ice volume remains at a record daily low, as it has been for more than a year. The image below shows Arctic sea ice volume through October 24, 2025.
The methane danger is also illustrated by the image below, adapted from an image issued by NOAA October 25, 2025, showing hourly methane averages recorded at the Barrow Atmospheric Baseline Observatory (BRW), a NOAA facility located near Utqiaġvik (formerly Barrow), Alaska, at 71.32 degrees North.
Climate Emergency Declaration
UN secretary-general António Guterres recently spoke about the need for “a credible global response plan to get us on track” regarding the international goal of limiting the global temperature rise. “The science demands action, the law commands it,” Guterres said, in reference to a recent international court of justice ruling. “The economics compel it and people are calling for it.”
What could be added is that the situation is dire and unacceptably dangerous, and the precautionary principle necessitates rapid, comprehensive and effective action to reduce the damage and to improve the outlook, where needed in combination with a Climate Emergency Declaration, as described in posts such as this 2022 post and this one and as discussed in the Climate Plan group.
Links
• Kevin Pluck - Sea ice visuals
https://seaice.visuals.earth
• Climate Reanalyzer
https://www.climatereanalyzer.org
• Danish Meteorological Institute - Arctic sea ice thickness and volume
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php
• NOAA - Global Monitoring Laboratory - Data Visualisation - flask and station methane measurements
https://gml.noaa.gov/dv/iadv
• Focus on Antarctica
https://arctic-news.blogspot.com/2025/09/focus-on-antarctica.html
• Antarctic sea ice in danger
https://arctic-news.blogspot.com/2025/10/antarctic-sea-ice-in-danger.html
• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html
• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html
• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html