Showing posts sorted by date for query high methane levels over. Sort by relevance Show all posts
Showing posts sorted by date for query high methane levels over. Sort by relevance Show all posts

Sunday, November 2, 2025

The threat of seafloor methane eruptions

Sea ice 

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 November 21, 2025.


The image below shows monthly Arctic sea ice volume in the past 25 years. Markers show April (blue) and September (red) volume, corresponding with the year's maximum and minimum. In 2025, Arctic sea ice reached a record low maximum volume as well as a record low minimum volume.

[ from earlier post ]
Warmer water flowing into the Arctic Ocean causes Arctic sea ice to lose thickness and thus volume, diminishing its capacity to act as a buffer that consumes ocean heat entering the Arctic Ocean from the North Atlantic. This means that - as sea ice thickness decreases - a lot of incoming ocean heat can no longer be consumed by melting the sea ice from below, and the heat will therefore contribute to higher temperatures of the water of the Arctic Ocean. The danger of this is described in the screenshot below.

[ screenshot from earlier post ]

Arctic sea ice extent was 1.91 million km² lower than 1981-2020 on November 21, 2025, a deviation from 1981-2010 of -3.34σ.

The image below shows that the global sea ice extent was 3.40 million km² lower than 1981-2020 on November 21, 2025, a deviation from 1981-2010 of -5.51σ. This is terrifying, given that we're currently in a La Niña.

The image below shows sea surface temperatures around Antarctica as high as 0.7°C or 33.3°F (at the green circle, on the left of Antarctica) on November 21, 2025. 


The image below shows sea surface temperatures around Antarctica as high as -0.9°C or 30.4°F (at the green circle, on the right of Antarctica) on November 21, 2025. 


The higher the water's salt content, the lower its melting point. Seawater typically has a salinity of about 3.5% (35 grams of salt per liter of water). Sea ice starts melting when the temperature rises to about -2°C (28.4°F). By contrast, freshwater remains frozen as long as the temperature remains below 0°C (32°F).

A study led by Alessandro Silvano (2025) finds that, over the years, surface waters have become more salty.


When surface waters become saltier, they sink more readily, stirring the ocean’s layers and allowing heat from the deep to rise. This upward heat flux can melt 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.

In addition to heat rising up from the deep, there is the danger that increasing amounts of both heat and carbon dioxide (CO₂), previously taken up by the ocean and stored in the deep ocean by sinking circumpolar waters, will instead remain at the surface and cause both atmospheric temperatures and CO₂ concentrations to rise.

Less sea ice extent means that less sunlight gets reflected back into space and instead gets absorbed by the sea surface, resulting in higher sea surface temperatures. Less global sea ice thus contributes to lower albedo. The image below, by Eliot Jacobson, shows the 36-month running average for the Earth albedo just hit yet another new record low, at 28.701%. 


Accelerating temperature rise

The image below, created with a screenshot from a Copernicus image, shows that, over the past few months, temperatures have risen by 0.5°C, i.e. from an anomaly (vs 1991-2020) of 0.41°C on June 23 to 0.91°C on November 22, 2025 (dark red line), getting close to if not exceeding temperature anomalies reached in 2024 (orange) and 2023 (yellow).

In fact, the temperature reached a new daily record high on November 22, 2025, and this occurred despite the fact that we're currently in a La Niña that suppresses temperatures, whereas temperatures were raised from May 2023 through April 2024 when El Niño conditions were dominant. 


The image below shows land-only monthly temperature anomalies from 1903-1915 through October 2025 (black squares). The Lowess 3-year smoothing trend (red line) points at 3°C getting crossed in the course of 2031 (dashed extension). The 1903-1915 base is not pre-industrial. Anomalies will be higher when using a genuinely pre-industrial base.


The image below shows land+ocean monthly temperature anomalies from 1903-1915 through October 2025 (black squares). The Lowess 3-year smoothing trend (red line) points at 2°C getting crossed before 2030 and 3°C getting crossed before 2040 (dashed extension). As said, the anomalies will be higher when using a genuinely pre-industrial base. 


The 3°C threshold is important since humans will likely go extinct with a 3°C rise and most life on Earth will disappear with a 5°C rise, as discussed in this 2019 post. 

The image below shows the October 2025 temperature anomaly from 1951-1980. Anomalies are very high, exceeding 10°C in areas over both the poles.


The combination image below highlights the October 2025 very high temperature anomalies (from 1951-1980), exceeding 10°C in areas over both the poles.


The image below shows the global monthly surface temperature anomalies from 1951-1980 through October 2025, when the anomaly was 1.37°C. 

Note that the 1951-1980 base isn't pre-industrial. When using a genuinely pre-industrial base, the temperature anomaly will be much higher, well above the thresholds that politicians at the Paris Agreement pledged wouldn't be crossed. 

Ominously, anomalies have kept rising over the past few months, and this occurred in the absence of El Niño conditions in 2025. 

The image below shows the global temperature standard anomaly for the 12 months from November 2024 through October 2025. 


The image below shows the standard deviation (Sd) anomalies from 1951-1980 of Arctic temperatures over the past few years, with a Standard Anomaly of 6.68σ reached in October 2025. 

The image below shows the standard deviation (Sd) anomalies from 1951-1980 of Arctic temperatures over the past few years, with a Standard deviation Anomaly of 4.59σ reached in October 2025.  


Sea surface temperature anomalies

The image below shows monthly sea surface temperature anomalies from 1951-1980 through September 2025, when the anomaly was 0.74°C. The image also shows that the anomaly in September 2023 was 0.901°C. 


The image below shows the standard deviation from 1951-1980 of the monthly sea surface temperature through September 2025, when it was 8.045σ. The image also shows that the standard deviation in August 2023 was 10.148σ. 


In statistics, the empirical rule states that in a normal distribution, 68% of the observed data will occur within one standard deviation (1σ), 95% within two standard deviations (2σ), and 99.7% within three standard deviations (3σ) of the mean. A 4σ event indicates that the observed result is 4 standard deviations (4σ) away from the expected mean. In a normal distribution, 99.993666% of data points would fall within this range. The chance for data to fall outside of 4σ is thus infinitesimally small.

Meanwhile, sea surface temperatures have remained very high. The image below shows sea surface temperature anomalies from 1981-2011 in the Northern Hemisphere, with anomalies as high as 9°C or 13.6°F visible in the path of the Gulf Stream (at the green circle). 


Wild weather swings

    [ 24+°C anomaly over part of Greenland ]
Wild weather swings are striking the world with accelerating intensity and ferocity. More than 1.4 million evacuated as second typhoon in a week slams into the Philippines, reports CNN. 

The image on the right shows temperature anomalies higher than 24°C at 2m in an area over Greenland on November 13, 2025.

The image below shows strong wind over Baffin Bay boosting temperatures over Greenland to levels as high as 12.9°C or 55.1°F (at the green circle) at 1000 hPa on November 13, 2025, as strong wind pushes warm air over Greenland, while cold Arctic air gets pushed down toward England. 


ENSO outlook, next El Niño likely to be devastating

[ click on images to enlarge ]
Currently, global sea ice is low and temperatures are high, despite the fact that La Niña conditions are suppressing the temperature. This should constitute a strong warning that temperatures look set to accelerate dramatically with the development of the next El Niño, likely to occur in the course of 2026.

According to a NOAA analysis issued Nov 13, 2025, La Niña continued over the past month, and La Niña is favored to continue into the Northern Hemisphere winter, with a transition to ENSO-neutral most likely in January-March 2026 (61% chance, image right). 

ENSO (El Niño-Southern Oscillation) has three states: El Niño (when temperatures are higher than average), La Niña (when temperatures are suppressed), and a neutral state. 

The image on the right, adapted from a November 2025 NOAA image, gives an ENSO outlook (CFSv2 ensemble mean, black dashed line) that favors La Niña to persist into the early Northern Hemisphere winter 2025-26, implying that temperatures will remain suppressed until early 2026.

[ click on images to enlarge ]
The image on the right, adapted from ECMWF, shows the ENSO anomaly and forecast for developments in Niño3.4 through November 2026, indicating that the next El Niño will emerge and grow in strength in the course of 2026.

The depth of the current La Niña is illustrated by the image below. The image shows strongly negative sea surface temperature anomalies (SSTA, NOAA OISST v2.1 data) in the Niño3.4 area in the Central Pacific, with a -0.98°C anomaly vs 1991-2020 on November 18, 2025, while the inset shows global SSTA vs 1991-2020 on November 18, 2025.  


NOAA considers La Niña conditions to occur when a one-month negative sea surface temperature anomaly of -0.5° C or less is observed in the Niño-3.4 region of the equatorial Pacific Ocean (5°N-5°S, 120°W-170°W) and an expectation that the 3-month Oceanic Niño Index (ONI) threshold will be met, and an atmospheric response typically associated with La Niña is observed over the equatorial Pacific Ocean. 

The graph below uses CDAS (Climate Data Assimilation System) data showing an anomaly of -1.202ºC on November 15, 2025.


The CDAS analysis below shows very low sea surface temperature anomalies in the Niño3.4 area on November 15, 2025. 


The CanSIPS forecast for March 2026 below shows high sea surface temperature anomalies in the central Pacific Ocean, indicating development of the next El Niño. The low sea surface temperature anomalies around Antarctica indicate areas where heavy melting will likely have taken place by March 2026. 


Antarctica

Sea ice extent is currently low at both poles. The low global sea ice extent at this time of year combined with high sea surface temperatures spells bad news for Antarctic sea ice, which typically reaches its minimum extent in February.

The image on the right shows Antarctic snow cover and sea ice concentration on November 21, 2025. 

The combination image below shows Antarctic sea ice concentration on November 19, 2025 (left) and Antarctic sea ice thickness on November 19, 2025 (right). 


The comparison image below shows the thickness of the Antarctic sea ice on October 6 and on November 21, 2025. 


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 while a developing El Niño is strengthening the danger. Ominously, the forecast of sea surface temperature anomalies for August 2026 below looks grim. 


The methane danger

This increases the danger that massive amounts of methane will erupt from the seafloor in 2026, further accelerating the temperature rise.

The methane danger is further illustrated by the images below. The image directly below shows methane as high as 2620 parts per billion (ppb) recorded by the NOAA 20 satellite at 487.2 mb on November 5, 2025 AM.


The image below shows hourly methane measurements well above 2400 ppb. The image is adapted from an image issued by NOAA November 9, 2025, showing methane hourly averages recorded in situ at the Barrow Atmospheric Baseline Observatory (BRW), a NOAA facility located near Utqiaġvik (formerly Barrow), Alaska, at 71.32 degrees North latitude.


The image below is a similar image, this time showing that the monthly average methane recorded at the same station is about 2050 ppb. 


In the video below, Guy McPherson discussed our predicament. 



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

• DMI (Danish Meteorological Institute) - Arctic sea ice thickness and volume
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php

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

• Climate Reanalyzer

• NOAA (National Oceanic and Atmospheric Administration) - Climate Prediction Center

• ECMWF (European Centre for Medium-Range Weather Forecasts) - charts
https://charts.ecmwf.int/products/seasonal_system5_nino_annual_plumes

• NASA (National Aeronautics and Space Administration) - GISS Surface Temperature Analysis
https://arctic-news.blogspot.com/p/pre-industrial.html

• When Will We Die?
https://arctic-news.blogspot.com/2019/06/when-will-we-die.html

• Tropicaltidbits
https://www.tropicaltidbits.com

• Feedbacks in the Arctic
https://arctic-news.blogspot.com/p/feedbacks.html

• NOAA - Global Monitoring Laboratory - Data Visualisation - flask and station methane measurements
https://gml.noaa.gov/dv/iadv

• Focus on Antarctica








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Tuesday, October 14, 2025

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. Before the Industrial Revolution, wood and plants were used for shelter and as building material. Plants also provided food for people and fodder for animals that were herded and that were used for food, ploughing, hunting, herding and transport. Biomass was also burned for heating, preparing food, cooking water, lighting and protection. 

Deforestation was the result of people's growing demand for biomass. Deforestation also increased due to trees getting cut down or burned as demand grew for land that could be used for urban purposes, as pasture or to grow more food and fodder.

[ click on images to enlarge ]

The 1850-1900 period that the IPCC uses as base to measure the temperature rise doesn't reflect pre-industrial well, for a number of reasons. Firstly, people's emissions pushed up temperatures long before that. Secondly, the 1850-1900 period was dominated by burning coal to provide heating and energy, which came with sulphur co-emission causing surface cooling, masking the temperature rise.

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).

[ from earlier post ]
The temperature has risen accordingly since those times. Deforestation and growth in irrigation and numbers of people, livestock and herded animals and their crop waste, sewage and manure resulted in emissions. While much of the forests could initially regrow, the net result was a gradual loss of trees and the cooling aerosols they previously provided and a gradual growth in emissions such as methane, carbon dioxide, carbon monoxide and black carbon (soot). 

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 (E3), the rise caused by people to negate that could also be included (H), 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

• Nullschool.net

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

• Aerosols

• Aboveground biomass in Australian tropical forests now a net carbon source - by Hannah Carle et al.
discussed on Facebook at: 

• Pre-industrial

• The World lost one third of forests

• The Role of Energy Quality in Shaping Long-Term Energy Intensity in Europe - by Ruta Gentvilaite et al. (2015)
https://www.mdpi.com/1996-1073/8/1/133

• 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
• Transforming Society

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html





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