Antarctic sea ice area reaches record daily low

Antarctic sea ice area remained at a record daily low on October 24, 2025, following a record daily low on October 23, 2025. Antarctic sea ice area was 12.40 million km² on October 24, 2025, a deviation from 1981-2010 of -3.57σ, as illustrated by the image below.

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.

[ 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.

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. 

This came with snowfall 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 situation is dire. An Antarctic Blue Ocean Event (sea ice approaching a low of one million km²) threatens to occur in February 2026, triggering an Arctic Blue Ocean Event later in 2026. There is a huge danger that this will result in massive amounts of methane erupting from the seafloor. 

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

Antarctic sea ice in danger

The Antarctic sea ice area was 12.54 million km² on October 17, 2025, the second lowest daily area (behind 2023) and a deviation from 1981-2010 of -4.15σ.

This low Antarctic sea ice area is alarming. Antarctic sea ice typically reaches its annual low in February. The record low of 1.09 million km² that was reached on February 24, 2023, was very close to a Blue Ocean Event, yet the deviation then was only -2.86σ.

High temperature anomalies over Antarctica and high sea temperatures are behind the low sea ice area. The image below shows how much higher the September 2025 temperature was than it was in 1951-1980.

[ 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, temperature anomalies were high in September 2025 and anomalies were as high as +4.22°C compared to 1979-2000 on October 14, 2025, which is remarkable given the absence of El Niño conditions. Record high daily temperatures were reached on each day of the period from 12 to 17 October 2025. The inset shows high polar temperature anomalies versus 1991-2020 on October 17, 2025.

[ click on images to enlarge ]

Meanwhile, Arctic sea ice volume remains at a record daily low, as it has been for more than a year, as illustrated by the image below. This contributes to low global sea ice, as this causes less sunlight to be reflected and instead more sunlight to be absorbed by the ocean surface. 

The global sea ice area was 3.45 million km² lower than 1981-2010 on October 17, 2025, a deviation from 1981-2010 of -4.47σ, as illustrated by the image below.

The image below shows Antarctic sea ice concentration on October 17, 2025.

The image below shows Antarctic sea ice thickness on October 17, 2025.

The situation is dire. An Antarctic Blue Ocean Event (sea ice approaching a low of one million km²) could occur in February 2026, triggering an Arctic Blue Ocean Event later in 2026.   

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.

Transform Society with the Climate Plan

[ image from this 2019 post, text discussed in earlier posts such as this 2022 one and links below ]

The Climate Plan calls for Transformation of Society in at least four sectors, as follows:

1. Energy - Generate clean, renewable energy with solar panels, turbines and batteries.

2. Food - Produce vegan-organic food and pursue synthetic food, solar food and precision fermentation.

3. Waste management - Pyrolyze organic waste with the biochar added to the soil.

4. Construction and Activities - Transition to online work, ordering, education and health diagnosis, using wood and green steel to construct buildings, vessels, bridges and water storage, while adding olivine sand to footpaths, bikeways, paths, gardens, beaches, forests and water bodies, and while letting eVTOL air taxis add extra mobility, battery exchange and mobile communications, in support of microgrids, WiFi, microwave and laser links.

The above transitions will help increase forests, as discussed in posts such as this one. Reforestation and afforestation efforts work best when including restoration of wildlife and creation of food forests as discussed in this post and in this post. A recent study led by Evan Fricke finds that with healthy populations of animals that disperse seeds, tropical forests can absorb up to four times more carbon. A 2024 study led by Maddi Artamendi finds a notable negative impact of reduced pollinator species diversity on plant reproductive success measures, such as seed set, fruit set and fruit weight. 

The images below illustrate the decline over time of wild mammals and birds, compared to humans, livestock and poultry. 

Further Links

• Kevin Pluck - Sea ice visuals
https://seaice.visuals.earth

• University of Bremen - sea ice concentration and thickness
https://seaice.uni-bremen.de/start

• Climate Reanalyzer

https://www.climatereanalyzer.org

• Focus on Antarctica
https://arctic-news.blogspot.com/2025/09/focus-on-antarctica.html

• Emissions and Temperature Rise
https://arctic-news.blogspot.com/2025/10/emissions-and-temperature-rise.html

• Seed dispersal disruption limits tropical forest regrowth - by Evan Fricke et al. (2025) https://www.pnas.org/doi/10.1073/pnas.2500951122

and
• Loss of pollinator diversity consistently reduces reproductive success for wild and cultivated plants - by Maddi Artamendi et al. (2024)
https://www.nature.com/articles/s41559-024-02595-2
discussed on Facebook at: 
https://www.facebook.com/groups/climateplan/posts/25746278341642263

• Wild mammals make up only a few percent of the world’s mammal biomass - by Hannah Ritchie (2022)

https://ourworldindata.org/wild-mammals-birds-biomass

• 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

Emissions and Temperature Rise

The image below shows the Planet by land biome, i.e. forests, grassland, desert, tundra and shrubland. Rainforests are common in equatorial areas and they have steady temperatures year-round and high precipitation allowing for evergreen and semi-evergreen trees. Boreal forests, also called Taiga, cover much of the planet’s northern latitudes and their trees are coniferous (non-shedding), while trees in temperate areas do shed their leaves (deciduous).

Forests come with many climate benefits. Trees take carbon out of the atmosphere and store the carbon in the trees and in the soil, thus reducing global warming. Less carbon dioxide in the atmosphere also reduces ocean acidification. The top layer (canopy) of rainforests contains giant trees that can grow to heights of 75 m (about 250 ft) or more. The canopy prevents much sunlight from reaching the ground, thus cooling the surface locally. Trees hold the soil together and can pump up water from deep in the soil and, through evaporation, keep the surface and soil cool, thus also avoiding erosion and reducing fire hazards.

So, trees are responsible for cooling in many ways. Trees can darken the surface, which can cause more sunlight to be absorbed, thus resulting in more warming, but trees can also cause cooling in another way. Trees also release terpines and other biogenic volatile organic compounds (BVOCs) into the air. These BVOCs can react chemically in the atmosphere to form aerosols that reflect incoming solar radiation and thereby cause global cooling. These aerosols can also act to start clouds to form that result in rainfall and that shade the surface, reflecting more solar radiation back into space and thus cause further global cooling. 

While BVOCs have many benefits, they can also indirectly increase potent greenhouse gases including ozone and methane by depleting hydroxyl. A study led by Gillian Thornhill found that this could cause half the cooling effects of BVOCs to be lost. A recent study led by James Weber found that, when all the effects are combined, they can reduce the net climate benefit of wide scale tree-planting by up to one third.

The above image shows that organic matter aerosol optical thickness (55 nm) as high as 0.93 τ was recorded over North Australia on October 14, 2025 06:00 UTC.

A recent study led by Hannah Carle finds that a transition from sink to source has occurred for the aboveground woody biomass of the Australian moist tropical forests. Forests need to be supported and not just for their capacity to sequester carbon. The net climate benefit of trees is huge and is underestimated. While trees can cause some warming, they also cause more cooling. Their BVOCs are responsible for some depletion of hydroxyl, but this should be no reason to withhold support for forests. Instead, climate action should strongly support forests, while greater hydroxyl abundance is best accomplished by cleaning up industry sectors such as agriculture, transport and electricity generation.

IPCC downplays the temperature rise

The IPCC downplays the temperature rise in efforts to hide some of the most effective and necessary action, e.g. by presenting the impact of land use, gases and aerosols in most peculiar ways. Instead of comparing the climate impact of forests versus agriculture in commonly comprehensible language, such as a rise in degrees Celsius, the IPCC uses technical terms to make things less comprehensible for the typical reader (and voter).

As an example, the IPCC seeks to present deforestation as a change in land use that results in greater cooling, e.g. by arguing that deserts reflect more light back into space. As another example, the IPCC makes it look as if the temperature started rising only from 1850-1900, in efforts to hide the huge impact of deforestation that took place before those years.

Of the 14.9 billion hectares of land on the planet, only 71% of it is habitable – the other 29% is either covered by ice and glaciers, or is barren land such as deserts, salt flats, or dunes. About 10,000 years ago, 57% of habitable land was covered by forest and 42% was covered by wild grassland and shrubs. In 2023, 45% of habitable land was used for agriculture, as illustrated by the image below.

People have been herding animals and burning or cutting down trees for thousands of years. While much of the forests could initially regrow, the result of people's activities was a strong increase in emissions of carbon dioxide, methane and black carbon.

The rise from 1750 to 2024 in methane, carbon dioxide and nitrous oxide is illustrated by the image on the right, based on IPCC and WMO data.

While emission by people did accelerate since the start of the Industrial Revolution and even more recently, the rise in emission by people had already started thousands of years ago with growth in agriculture, herding of animals and associated deforestation, as illustrated by the combination image below, based on Ruddiman et al. (2015).

The temperature has risen accordingly since those times.

[ from earlier post ]

Emissions caused by people's activities include carbon dioxide, methane and black carbon. A 2013 study by Bond et al. calculates that black carbon has a warming effect of about 1.1 W/m², part of which is caused by black carbon darkening the snow and ice cover since pre-industrial times, as discussed on the aerosols page. By some calculations, the temperature in 1520 had risen by 0.29°C, compared to thousands of years earlier.

September 2025 temperature anomaly

The image below shows how much higher the September 2025 temperature was than it was in 1951-1980. 

The above image shows that the September 2025 temperature anomaly was high over both poles and especially high over some areas in Antarctica, where anomalies higher than +10°C versus 1951-1980 were recorded. 

As the image below shows, the temperatures recorded over Antarctica throughout September 2025 were higher than in most earlier years, while a record daily high temperature was recorded on October 10, 2025, a +3.62°C anomaly compared to 1979-2000. The inset shows high temperature anomalies versus 1991-2020 at both poles on October 10, 2025.

The image below shows that the global September 2025 temperature anomaly was 1.306°C higher than 1951-1980. Note that the 2025 anomalies were reached under borderline La Niña conditions that suppress temperatures and that the monthly temperature anomaly would be significantly higher when calculated from 1850-1900, which is typically used by the IPCC as baseline. 

[ Temperature Rise, click on images to enlarge ]

The full historic temperature rise and the rise to come soon could be much higher, as described on the image and below. The inset is also displayed and discussed in more detail below. 

Emissions and Temperature Rise

The observed temperature rise (O) is actually masked by aerosols (M) and the IPCC only includes the rise from the period 1850-1900, ignoring the rise before the period 1850-1900 (P) and the rise that took place to negate the natural fall in temperature. Aerosols could fall out of the air soon, so when adding things up (E1+E2), the historic temperature rise from pre-industrial (O+M+P) is huge. 

When also taking into account that the temperature would have fallen naturally (i.e. in the absence of these emissions and in line with Milankovitch cycles, the rise caused by people to negate that could also be included (E3), adding up to an even higher historic temperature rise (O+M+P+H).

Additionally, the full impact of all past emissions may not be fully felt yet, e.g. the full effect of carbon dioxide emissions reaches its peak only a decade after emission (E4). Furthermore, humans are likely to continue to cause emissions in the near future (E5). Finally, additional releases of greenhouse gases are likely to come from what was once called permafrost and from sinks turning into sources, resulting in an additional rise that's already baked into the cake (E6). Therefore, the historic rise plus the rise to come soon (O+M+P+H+F) may approach 5°C.

The diagram below further illustrates the importance of feedbacks and deforestation. Removal of trees has caused deforestation and soil carbon loss since prehistoric times, in turn causing emissions including carbon dioxide, methane and black carbon, while also reducing cooling aerosols released by trees and while also reducing the heat buffer of evaporation that previously cooled the atmosphere. Since prehistoric times, burning wood and deforestation has caused emissions of black carbon and dust that blackened the snow and ice cover, thus speeding up its decline. 

[ from earlier post ]

The image below illustrates how much the temperature may have risen from pre-industrial times and how much potential there is for a 3°C rise as early as in 2026.

[ from earlier post ]

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

• NASA - Earth by Biome

https://earthobservatory.nasa.gov/biome

• Nullschool.net

https://earth.nullschool.net

• Climate-driven chemistry and aerosol feedbacks in CMIP6 Earth system models - by Gillian Thornhill et al. (2021) 

https://acp.copernicus.org/articles/21/1105/2021

• Missing the forest for the trees: The role of forests in Earth’s climate goes far beyond carbon storage - by Sarah Blichner and James Weber (2024) 
https://thebulletin.org/2024/05/missing-the-forest-for-the-trees-the-role-of-forests-in-earths-climate-goes-far-beyond-carbon-storage

• Chemistry-albedo feedbacks offset up to a third of forestation’s CO2 removal benefits - by James Weber et al. (2024) 

https://www.science.org/doi/full/10.1126/science.adg6196

• Aerosols

https://arctic-news.blogspot.com/p/aerosols.html

• Aboveground biomass in Australian tropical forests now a net carbon source - by Hannah Carle et al.

https://www.nature.com/articles/s41586-025-09497-8

discussed on Facebook at: 

• Pre-industrial

https://arctic-news.blogspot.com/p/pre-industrial.html

• The World lost one third of forests

https://ourworldindata.org/world-lost-one-third-forests

• WMO news release: Carbon dioxide levels increase by record amount to new highs in 2024
https://wmo.int/news/media-centre/carbon-dioxide-levels-increase-record-amount-new-highs-2024
WMO Greenhouse Gas Bulletin - No. 21 (issued October 15, 2025)
https://wmo.int/files/greenhouse-gas-bulletin-no-21
discussed on Facebook at:
https://www.facebook.com/groups/arcticnews/permalink/10163357891699679

• Record low Arctic sea ice volume minimum highlights methane danger

https://arctic-news.blogspot.com/2025/10/record-low-arctic-sea-ice-volume-highlights-methane-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

Methane Danger

Global methane concentrations have not risen as strongly during El Niño years 2023 and 2024 as they did from 2020 to 2022, as illustrated by the above image, showing monthly methane concentrations through May 2025, and the image below, showing annual methane growth through 2024. The question is, why did the growth in methane concentrations slow down in 2023 and 2024?

Is the rise in methane releases partly masked? 

One possible mechanism, described here earlier, is that, as temperatures increase and water vapor in the atmosphere increases accordingly (7% more water vapor for every 1°C warming), more hydroxyl in the atmosphere, more methane gets broken down by the increased hydroxyl in the atmosphere. Accordingly, the stronger methane breakdown by more hydroxyl in 2023 and 2024 may give the impression that methane releases appeared to slow down, whereas methane releases may actually have kept growing and because this growth was getting masked, it was overlooked.

In other words, methane releases may have continue to grow at accelerating pace, but since an increasingly large part of the methane releases was decomposed by more hydroxyl, the growth in methane concentrations in the atmosphere only appeared to slow down because methane releases were partly masked by growth in hydroxyl, as discussed in earlier posts such as this 2017 one.

Where could the extra methane releases have come from? In part, they may have come from seafloor methane releases. In a 2014 post, methane releases were estimated at 771 Tg/y, whereas the IPCC's estimate was 678 Tg/y. That post estimated methane from hydrates and permafrost at 13% of total methane emissions, whereas the IPCC's estimate was a mere 1% of total methane emissions.

According to this mechanism, methane releases actually started to increase more strongly (partly due to more methane erupting from the seafloor of oceans) from the early 2000s, but hydroxyl also kept increasing, slowing down growth in methane concentrations. Eventually, increasing methane releases (including seafloor methane releases) progressively overwhelmed the growth in hydroxyl, contributing to a stronger rise in overall methane concentrations in the atmosphere. 

The growth in methane concentrations peaked in 2022, but after that, the emerging El Niño in 2023 and 2024 drove up temperatures and thus also hydroxyl. So, while growth in methane releases may appear to have slowed down over the past few years, this mechanism suggests that some methane releases may be overlooked, particularly methane releases for the seafloor of oceans, due to increased hydroxyl production in line with more water vapor in the atmosphere over the past few years.

Earthquake danger

Further illustrating the danger of seafloor methane releases, the combination image below shows an earthquake that occurred on October 10, 2025, in between South Africa and Antarctica (left). Methane at 1000 mb (near surface) shows up in a magenta-colored area in between South Africa and Antarctica, indicating methane releases of 1980 ppb and higher (right).

Note that the high methane concentrations near Antarctica are not in the same spot where the earthquake occurred. This can be attributed to the wind moving air clockwise around Antarctica. The combination image below shows wind at 10 m (left) and at 250 mb or hPa (right) on October 11, 2025.

To watch the wind at 1000 hPa or mb (near surface) move around and over Antarctica on October 12, 2025, click on this nullschool.net link. 

Danger of increase snowfall over Antarctica

The combination image below shows a distorted Jet Stream (250 hPa) moving over Antarctica, which results in high preciptable water anomalies over that area (left) and snowfall (right).

The danger of increased snowfall over Antarctica is described in the image below. 

[ screenshot from earlier post ]

The methane danger has been described in many earlier posts, e.g. the image below is from a 2014 post. The image shows a polynomial trend based on IPCC AR5 data from 1955 to 2011, pointing at methane reaching mean global levels higher than 3000 ppb by the year 2030. If methane starts to erupt in large quantities from clathrates underneath the seafloor of oceans and from thawing permafrost, then something like this may well happen and the amount of methane in the atmosphere could double by 2030. 

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

• Focus on Antarctica
https://arctic-news.blogspot.com/2025/09/focus-on-antarctica.html

• Record low Arctic sea ice volume minimum highlights methane danger
https://arctic-news.blogspot.com/2025/10/record-low-arctic-sea-ice-volume-highlights-methane-danger.html

• Global methane concentration and annual growth
https://gml.noaa.gov/ccgg/trends_ch4
also discussed on Facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10163340957609679

• 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