Saturday, January 18, 2025

Why downplay the need for action?

The 2024 global average surface temperature was 1.55°C above the 1850-1900 average, according to WMO’s consolidated analysis of six datasets. 

[ click on images to enlarge ]
Differences between datasets are mainly due to the ways temperatures are measured, e.g. ERA5 measures the temperature of the air above oceans, whereas NASA and NOAA measure the surface temperature of the water, which is lower. There can also be differences in how temperatures are measured in areas with sea ice - the sea ice can be measured, or the water underneath the sea ice, or the air above the sea ice. Also, in some areas there once was sea ice that has meanwhile disappeared. Different ways of measuring things can raise the temperature record by as much as 0.2°C and even more in case of earlier years, where the margin of error is also larger. 

Importantly, the temperature rise in the above image is compared to the period 1850-1900, which is not pre-industrial. When using a genuinely pre-industrial base, the temperature anomaly may already have been above the 2°C threshold in 2015, when politicians at the Paris Agreement pledged that this threshold wouldn't be crossed.

[ from earlier post ]
“Individual years pushing past the 1.5 degree limit do not mean the long-term goal is shot", UN Secretary-General Antóno Guterres says: “It is important to emphasize that a single year of more than 1.5°C for a year does NOT mean that we have failed to meet Paris Agreement long-term temperature goals, which are measured over decades rather than an individual year", WMO Secretary-General Celeste Saulo adds. 

However, for this argument to hold, the average anomaly would need to fall to under 1.5°C from now. Should we really have to wait for another decade or two, before a confirmation is allowed to be issued that 1.5°C has been crossed. Isn't such a mandate part of downplaying how dire the situation is, an effort to delay the necessary action? Moreover, does such a mandate make sense? 
[ click on images to enlarge ]
[ for more background, also view the Extinction page ]

To illustrate this point, the above image uses NASA anomalies (blue dots) that are conservatively compared to NASA's default 1951-1980 base, with data going back to 2010. The image thus shows a 30-year review period centered around January 1, 2025. Eight imaginary years of data have been added beyond existing data, extending the trend into the future (yellow dots). The wide pink trend is based on both NASA existing data and these imaginary data, jointly covering data from 2010-2032. The narrow black trend is not based on imaginary data, it is purely based on existing data, from 2010-2024, showing the potential for such a trend to eventuate when using existing (i.e. past) data only.

In case such a trend would indeed eventuate, confirmation of the crossing of the 1.5°C threshold should NOT be delayed until all the years of a 30-year period have been entirely completed. In fact, 2°C (vs 1951-1980) would already be crossed early 2026. In the course of 2032, a 16°C rise would be reached, while the average anomaly for the period 2010-2032 would be higher than 3°C (vs 1951-1980) with still 7 years to go before the 30-year period would be completed.

Warnings about the potential for such a rise have been sounded before, e.g. see the extinction page and the update of the image below with daily data and added trends.

[ temperature anomaly with ENSO shading, trends added, click on images to enlarge ]
While La Niña conditions are definitely present in January 2025, the La Niña is expected to be short-lived. Temperatures are typically suppressed during La Niña. Despite temperatures being suppressed, the global surface air temperature reached 13.28°C on January 20, 2025, the highest temperature on record for the time of year, according to ERA5 data. Temperatures keep rising, as indicated by the trends added to the data, despite La Niña. Will a new El Niño emerge in the course of 2025?

Human extinction at 3°C

If the temperature does indeed keep rising rapidly, the anomaly compared to pre-industrial may soon be higher than 3°C, implying that humans are already functionally extinct, especially if no decisive, comprehensive and effective action is taken.

Analysis by Shona and Bradshaw (2019) finds that, due to co-extinction, global biodiversity collapse occurs at around 5°C heating, as discussed in this 2019 post. The post adds the warning that a rise of more than 5°C could happen within a decade, possibly by 2026, and that humans who depend on many other species will likely go extinct with a 3°C rise.


A recent study by Joseph Williamson et al. finds that many species that live together appear to share remarkably similar thermal limits. That is to say, individuals of different species can tolerate temperatures up to similar points. This is deeply concerning as it suggests that, as ecosystems warm due to climate change, species will disappear from an ecosystem at the same time rather than gradually, resulting in sudden biodiversity loss. It also means that ecosystems may exhibit few symptoms of heat stress before a threshold of warming is passed and catastrophic losses occur. 

Arctic temperatures and sea ice

As mentioned above, different ways of measuring arctic temperatures can lead to different results. The combination image below shows that a different smoothing radius can result in different anomalies. Gray areas signify missing data. Ocean data are not used over land nor within 100 km of a reporting land station.


The image below shows December 2024 Arctic temperature anomalies compared to 1951-1980 using ERA5 data.

The above image raises the question as to what caused the low anomalies over Greenland and Baffin Bay, compared to the rest of the Arctic. Consider the following:  

The increase in the Earth's energy imbalance results in an increase in kinetic energy in the atmosphere and oceans, i.e. stronger wind and stronger ocean currents, both in longitudinal and latitudinal directions. An earlier post points at a study that found increased kinetic energy in about 76% of the upper 2,000 meters of global oceans, as a result of intensification of surface winds since the 1990s.

While the wind overall is strengthening, the wind mainly appears to be strengthening in latitudinal directions. The Coriolis Effect contributes to that, but strengthening of latitudinal winds appears to be getting stronger over the years. Contributing to strengthening latitudinal wind is loss of sea ice at the poles, which comes with loss of albedo, a self-reinforcing feedback that contributes to polar amplification of the temperature rise.

Polar amplification narrows the difference in temperature between the Equator and the Poles, which results in a relative slowing down of the speed at which heat flows from the Equator to the poles (longitudinal wind). This causes changes in both wind patterns and ocean currents, such as deformation of the Jet Stream, slowing down of the Atlantic meridional overturning circulation (AMOC), and changes in ocean currents around Antarctica that carry heat from the Southern Ocean closer to Antarctica and from there to the deeper ocean. 

Deformation of the Jet Stream can cause cold air from the Arctic to descend over the continents. Meanwhile, the temperature of the sea surface keeps increasing. In other words, the temperature difference between land and sea can increase, and this can occur especially during the  in turn can strengthen latitudinal wind. 

While such conditions vary with the weather, all such mechanisms can contribute to strengthening wind, especially in latitudinal directions, as illustrated by the image below.


The above image shows the wind strength anomaly at 250 hPa in December 2024. The image below shows how this keeps cold air in December 2024 at 250 hPa over elevated land in the Arctic in place, thus keeping temperatures low over Greenland and Baffin Island. 


At the same time, as said, ocean heat keeps increasing, resulting in melting of sea ice from below. The image below shows Arctic sea ice extent through January 19, 2025. 

[ Arctic sea ice extent, click on images to enlarge ]
During the first few months of the year, Arctic sea ice is still growing in extent. In the above image, the red line and red marker shows 2025 sea ice extent. Dots mark Arctic sea ice extent on January 19 for the respective year and Arctic sea ice extent was at a record low for the time of year on January 19, 2025, despite La Niña conditions. 

A new El Niño may emerge in the course of 2025, while both Arctic sea ice extent and volume are at record low, while numerous self-reinforcing feedbacks are kicking in with accelerating ferocity and while further mechanisms are active that drive up temperatures such as high sunspots. Such a combination of mechanisms could cause a huge temperature rise and a Blue Ocean Event in 2025, threatening huge amounts of methane to erupt from the seafloor.

[ Northern Hemisphere sea surface temperature anomaly, click to enlarge] 
[ Arctic sea ice volume, click to enlarge ]
The above image shows a green circle south of Svalbard with a 5.1°C sea surface temperature on January 18, 2025, 3.4°C higher than 1981-2011. 

High ocean temperatures result in low Arctic sea ice volume, as illustrated by the image on the right and as discussed in this earlier post.

Guy McPherson discussed the consequences of an ice-free Arctic Ocean in the video below, adding that "a near-term, ice-free Arctic Ocean—the so-called Blue Ocean Event—is the extinction-causing event over which we have the least control. The rate of environmental change in the wake of such an event will suffice to cause the extinction of all life on Earth. 
I’m not a fan." 


Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.



Links

 • WMO confirms 2024 as warmest year on record at about 1.55°C above pre-industrial level
https://wmo.int/news/media-centre/wmo-confirms-2024-warmest-year-record-about-155degc-above-pre-industrial-level

• Met Office - 2024: record-breaking watershed year for global climate 
https://www.metoffice.gov.uk/about-us/news-and-media/media-centre/weather-and-climate-news/2025/2024-record-breaking-watershed-year-for-global-climate

• Berkeley Earth - Global Temperature Report for 2024 
https://berkeleyearth.org/global-temperature-report-for-2024

• NASA - Goddard Institute Surface Temperature (GISTEMP v4) analysis 
https://data.giss.nasa.gov/gistemp

• NASA - Temperatures Rising: NASA Confirms 2024 Warmest Year on Record 

• NOAA - 2024 was the world’s warmest year on record 
https://www.noaa.gov/news/2024-was-worlds-warmest-year-on-record

• Paris Agreement
https://unfccc.int/process-and-meetings/the-paris-agreement

• pre-industrial

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

• Clustered warming tolerances and the nonlinear risks of biodiversity loss on a warming planet - by Joseph Williamson et al.
also discussed on Facebook at: 

• Sunspots
https://arctic-news.blogspot.com/p/sunspots.html

• Climate Reanalyzer
https://climatereanalyzer.org

• Arctic and Antarctic Data Archive System (ADS) of the National Institute of Polar Research of Japan
https://ads.nipr.ac.jp

• nullschool.net
https://earth.nullschool.net

• Double Blue Ocean Event 2025?
• Guy McPherson - consequences of an ice-free Arctic Ocean

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

• The first ice-free day in the Arctic Ocean could occur before 2030 - by Céline Heuzé et al. https://www.nature.com/articles/s41467-024-54508-3
also discussed on facebook at: 

• 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

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Monday, January 6, 2025

Sea ice decline January 2025

Antarctic sea ice

[ Antarctic sea ice, click on images to enlarge ]
The above images, adapted from University of Bremen and ClimateReanalyzer.org, illustrate the decline in thickness (in cm) and of Antarctic sea ice between August 27, 2024, and January 9, 2025, and the sea ice concentration on January 9, 2025.

The compilation image below shows the Southern Hemisphere on January 5, 2025, when the sea surface temperature off the coast of East Antarctica was 1.6°C at the green circle (image left), an anomaly from 1981-2011 of 1.8°C (image right).

[ SH Sea surface temperature on January 5, 2025, click on images to enlarge ]
Changes to ocean currents can contribute to more heat accumulating at the ocean surface and underneath the surface, resulting in more Antarctic sea ice melting from below and losing thickness. Where the temperature of the (saline) ocean water rises above -1.8°C (28.7°F), the sea ice will start melting away from below.

[ SH Sea surface temperature on January 8, 2025, click on images to enlarge ]
The above compilation image shows the Southern Hemisphere on January 8, 2025, when the sea surface temperature of the Pacific Ocean was 22.5°C at the green circle (image left), an anomaly of 5.2°C compared to 1981-2011 (image right).


The above image shows zonal mean ocean temperature trends down to 2000 m, from Cheng et al. 


The above image, from Berkeley Earth, illustrates the importance of Antarctic Sea ice loss in accelerating the temperature rise.  

High temperatures despite La Niña

The image below, adapted from NOAA, shows monthly temperature anomalies colored by ENSO values.

[ temperature anomaly colored by ENSO values, click on images to enlarge ]
While La Niña conditions are strongly present in January 2025, the La Niña is expected to be short-lived.


Temperatures are typically suppressed during La Niña. Despite temperatures being suppressed, the global surface air temperature reached 13.23°C on January 10, 2025, the highest temperature on record for the time of year, according to ERA5 data. Temperatures keep rising, as indicated by the trends in the image below. Will a new El Niño emerge in the course of 2025?

[ temperature anomaly with ENSO shading, trends added ]
The image below, created with NASA data through December 2024 while using a 1903-1924 custom base, illustrates that the monthly temperature anomalies have been above 1.5°C compared to this base for 18 consecutive months (from July 2023 through December 2024). The red line shows a trend (2-year Lowess Smoothing) associated with recent data and the trend indicates that the anomaly is rising.

[ monthly temperature anomalies compared to 1903-1924 ]
The image below shows that temperature anomalies for the past two years (2023 and 2024) have been at least 1.5°C above this custom 1903-1924. The red line again shows a 2-year Lowess Smoothing trend. 

[ 2023 and 2024 temperature anomalies compared to 1903-1924 ]
Note that the 1903-1924 base is not pre-industrial. When using a genuinely pre-industrial base, anomalies may be well above 2°C, as discussed at the pre-industrial page and in many earlier posts such as this one.

Sea surface temperature anomalies are also very high, as high as 8.5°C off the coast of Japan (at the green circle) on January 8, 2025.

[ Sea surface temperature anomaly on January 8, 2025 ]
The probabilities of El Niño conditions are expected to rise in the course of 2025. Keep in mind that the last El Niño wasn't even very strong. Moving from the bottom of a La Niña to the peak of a strong El Niño could make a difference of more than 0.5°C, as illustrated by the image below.

[ Temperature rise due to El Niño from earlier post ]
In a cataclysmic alignment, the upcoming El Niño threatens to develop while sunspots that are higher than expected are peaking in July 2025. The temperature difference between maximum versus minimum sunspots could be as much as 0.25°C. 

There are numerous additional mechanisms that could strongly accelerate the temperature rise, such as loss of sea ice and changes in ocean currents that could cause oceans to take up less heat and more heat to instead remain in the atmosphere. The dangers increase as sea surface temperatures keep rising.

[ Global Sea surface temperature ]
The Northern Hemisphere, where seasonal temperature peaks are more extreme, could be hit strongly. One of the largest dangers is that huge amounts of methane could erupt from the seafloor of the Arctic Ocean and from thawing permafrost. The images above and below illustrate the danger, showing an even steeper rise of sea surface temperatures in the Northern Hemisphere. 

[ NH Sea surface temperature ]
As temperatures keep rising, feedbacks can be expected to kick in with accelerating ferocity, such as more water vapor in the atmosphere, less lower clouds and changes to wind patterns, further accelerating the temperature rise and contributing to extreme weather disasters hitting the world more frequently over larger areas, with greater intensity and for longer periods. On land on the Northern Hemisphere, the danger of rapidly rising temperatures is particularly high. This can trigger widespread flooding, fires, drought, famine, heat stress, storms and other weather disasters, while crop loss, loss of habitable land and corrupt politicians threaten to cause violent conflicts to erupt around the world. 

[ Aerosols, from earlier post ]
As illustrated by the above combination image, changes in aerosols could cause temperatures to rise strongly in the Northern Hemisphere and in particular in the Arctic. As industrial activity grinds to a halt, temperatures could rise due to a loss of cooling aerosols that are currently masking the full wrath of the temperature rise, as discussed in earlier posts such a as this one. 

At the same time, releases of heating aerosols could increase due to more burning of wood and biofuel, more forest fires, peat field fires and urban fires, and more burning of industrial facilities and waste pits. Black and brown carbon cause the air temperature to rise, while they also darken the surface when settling down, thus further speeding up the decline of the snow and ice cover in the Arctic. 

[ Arctic sea ice volume ]
These mechanisms could jointly cause the global temperature to rise above 3°C from pre-industrial and drive many species (including humans) into extinction by 2026, as has been discussed in many earlier posts such as this one. 

Meanwhile, Arctic sea ice volume remains at a record low for the time of year. The image on the right, from dmi.dk, shows volume through January 13, 2025 (black arrow points at 2025 Arctic sea ice volume). 

High sea surface temperature anomalies are forecast for the Arctic Ocean for August 2025, as illustrated by the image below, from tropicaltidbits. 

[ Sea surface temperatures anomalies ]
As illustrated by the image below, very high temperature anomalies forecast over the Arctic Ocean for October 2025.

[ Temperature Anomalies (2 m) ]
  
Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.



Links

• Double Blue Ocean Event 2025?
https://arctic-news.blogspot.com/2024/10/double-blue-ocean-event-2025.html

• Did a Terminal Temperature Acceleration Event start in December 2024?

• Record High Temperatures in the Ocean in 2024 - by Lijing Cheng et al. (2025)

• Berkeley Earth
• NOAA - Monthly Temperature Anomalies Versus El Niño/La Niña


• Copernicus - Global surface air temperature
https://pulse.climate.copernicus.eu

• NASA - GISS Surface Temperature Analysis

• Paris Agreement thresholds crossed 
https://arctic-news.blogspot.com/2024/08/paris-agreement-thresholds-crossed.html

• NOAA - National Centers for Environmental Information - Climate at a Glance - Global Time Series

• pre-industrial

• Sunspots

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Monday, December 9, 2024

Did a Terminal Temperature Acceleration Event start in December 2024?

Terminal Temperature Acceleration?

On December 30, 2024, the temperature was at a record high for the time of year. Given that La Niña suppresses temperatures, the question is what is driving up the temperature. 


The red dots in the above image are Copernicus ERA5 global daily mean near-surface (2m) air temperature anomalies December 13, 2022 through December 30, 2024, compared to a 1991-2020 base (left vertical axis) and a 1901-1930 base (right vertical axis). 

The pink shading indicates El Niño (end May 2023 to early May 2024) and the blue shading indicates ENSO-neutral conditions and La Niña. The gray shading indicates uncertainty regarding ENSO and the potential for Terminal Temperature Acceleration. 

Two trends are added based on these data (red dots). The linear trend (black) shows a steady, rapid rise. The non-linear trend (red) better follows variable mechanisms such as El Niño and sunspots, and the red trend indicates that a Terminal Temperature Acceleration Event may have started end December 2024 (the area with the grey shading). 

The grey shading may seem to be a grey area, but note that as La Niña will gradually decline in the course of 2025 (as predicted), the suppressing impact that La Niña has on temperatures will disappear and the prospect for a steep rise can be expected to become more manifest, as indicated by the red trend. Furthermore, as discussed below and in earlier posts such as this one, there are additional mechanisms that jointly and through their interaction increase the potential for a steep temperature rise in the course of 2025. 

Pre-industrial base
[ click on images to enlarge ]

The above comparison image illustrates that the use of a 1901-1930 base instead of the default Copernicus 1991-2020 base comes with an adjustment of the temperature anomaly of 0.91°C. Note that neither of these bases are pre-industrial. As discussed at the pre-industrial page, using pre-industrial as a base requires a further adjustment of as much as an additional 0.99°C, which would correspond with a total temperature anomaly for the year 2023 of as much as 2.47°C.

The image below, created with NASA data through November 2024 while using a 1903-1924 custom base, illustrates that the monthly temperature anomaly has been more than 1.5°C above this base for 17 consecutive months (from July 2023 through November 2024). The red line shows a trend (2-year Lowess Smoothing) associated with recent data and the trend indicates that the anomaly is rising.


Note that the 1903-1924 base is not pre-industrial. When using a genuinely pre-industrial base, anomalies such as the above-mentioned 1.89°C for February 2024 will exceed 2°C, as discussed at the pre-industrial page.

El Niño–Southern Oscillation (ENSO)

The current La Niña is predicted to be weak and short-lived, as illustrated by the image below, from NOAA, with probabilities for an El Niño getting progressively higher in the course of 2025.


The image below, adapted from NOAA, confirms that La Niña is expected to persist through February-April 2025.


The image below, adapted from NOAA, shows monthly temperature anomalies versus El Niño/La Niña through November 2024.


Since a La Niña typically suppresses temperatures, the question arises as to what is causing the temperatures to remain high. The strength of La Niña is also discussed here and here on facebook.

Temperature maps November 2024


As the images above and below show, temperature anomalies in November 2024 were particularly high in the Arctic.


The image on the right also shows temperature anomalies versus 1951-1980 for November 2024 over the Arctic, this time using NCEP/NCAR data.

Keep in mind that, while the 1951-1980 base for the above maps is NASA's default base, none of the bases used in the above images is pre-industrial. As said, anomalies from a pre-industrial base are higher.

Carbon dioxide keeps rising rapidly

Carbon dioxide (CO₂) keeps rising rapidly. On December 31, 2024, the CO₂ concentration reached 427.16 parts per million (ppm) at Mauna Loa, Hawaii, after reaching an earlier peak of 427.85 ppm on December 11, 2024, as illustrated by the image below, adapted from NOAA. 

The mean annual carbon dioxide was 424.61 ppm in 2024, an increase of 3.53 ppm compared to 2023 and the highest annual growth on record. This record high growth rate indicates that emissions of carbon dioxide are increasing while carbon sinks are weakening at the same time.  


A trend, based on 2015-2024 annual data, points at 1200 ppm CO₂ getting crossed in the year 2032.


The above trend illustrates that the clouds tipping point could get crossed in early 2032 due to rising CO₂ alone, which on its own could push temperatures up by an additional 8°C. The clouds tipping point is actually at 1200 ppm CO₂e, so when growth of other greenhouse gases and further mechanisms is taken into account, the tipping point could be crossed much earlier than in 2033. 

Mechanisms behind accelerated temperature rise

Research led by Helge Goessling suggests that global warming itself may be reducing the number of low clouds, resulting in less sunlight getting reflected back into space. “If a large part of the decline in albedo is indeed due to feedbacks between global warming and low clouds, as some climate models indicate, we should expect rather intense warming in the future,” Helge Goessling warns.

A Terminal Temperature Acceleration Event may occur soon due to a number of mechanisms, incl.:
- falling sea ice volume causing hydrates to destabilize, resulting in methane eruptions
- falling albedo as a result of reduction in sea ice extent
- falling albedo as a result of a reduction in lower clouds      
- El Niño developing in the course of 2025
- sunspots reaching a maximum in the current cycle (predicted to occur July 2025)
- reductions in sulfur aerosols combined with an increase in black carbon and brown carbon 
- less ocean heat reaching deeper parts of the ocean as a result of changes in ocean currents
  (see below)

Atlantic Meridional Overturning Circulation (AMOC)
[ Zonal and meridional flow, from Freshwater lid ]
[ Gulf Stream, from Freshwater lid ]
[ AMOC, from Freshwater lid ]
[ Global Ocean Circulation System, from Freshwater lid ]

For more details on the above mechanisms also have a look at the post Double Blue Ocean Event 2025?, which warns about the potential for dramatic ice decline at both poles.

Antarctic sea ice


[ Antarctic sea ice thickness in cm ]
The above compilation of four images by the University of Bremen and the image on the right illustrate the decline in Antarctic sea ice thickness between August 27, 2024, and December 29, 2024.

Changes to ocean currents can cause more heat 
to accumulate at the ocean surface, resulting in more Antarctic sea ice melting from below and losing thickness. Where the temperature of the (saline) ocean water rises above -1.8°C (28.7°F), the sea ice will start melting away. 

The image below shows the Southern Hemisphere 
on December 22, 2024, when the sea surface temperature off the coast of East Antarctica was 0.1°C at the green circle (image left), an anomaly from 1981-2011 of 1.4°C (image right).


Arctic sea ice

In 2023, North Atlantic (0-60°N 0-80°W) sea surface temperature anomalies vs 1882-2010 rose strongly in line with El Niño. In 2024, temperature anomalies remained consistently high, despite La Niña conditions present at the end of 2024.


As illustrated by the images above and below, the North Atlantic sea surface temperature was 21.31°C on December 26, 2024, a record high for the time of year and 1.03°C above 1982-2010. For much of 2024, the anomaly has been higher than it was in 2023.


As discussed in earlier posts, Arctic sea ice has also become very thin, diminishing its capacity to act as a buffer that consumes ocean heat entering the Arctic Ocean from the North Atlantic. Of the combination image below, the top part is adapted from an image by the Danish Meteorological Institute and this illustrates that both maximum- and minimum Arctic sea ice volume reached a new record low in September 2024. Markers for September (red) and April (blue) correspond with the year's minimum- and maximum volume.


One out of many dangers of rising temperatures is that, as Arctic sea ice keeps declining in volume while the water of the North Atlantic keeps heating up, more heat will reach the seafloor of the Arctic Ocean, destabilizing methane hydrates contained in sediments at the seafloor and resulting in eruptions of huge amounts of methane, as illustrated by the bottom part of the above combination image. 

The danger is particularly large in the East Siberian Arctic shelf (ESAS), where the sea has a mean depth of less than 50 m. This shallow depth makes it easier for heat to reach the seafloor and destabilize hydrates contained in sediments at the seafloor, resulting in methane eruptions. This shallow depth also means there is less opportunity for the methane to be broken down while rising in the water. 

As illustrated by the image on the right, Arctic sea ice volume was at a record low for the time of year on December 31, 2024.

On December 29, 2024, Arctic sea ice extent was at a record low for the time of year, as illustrated by the image below, adapted from ads.nipr.ac.jp. 






The above image shows Arctic sea ice extent in December, a month when Arctic sea ice is growing in extent. The red line shows 2024 sea ice extent through December 29, 2024. Dots mark Arctic sea ice extent on December 29 for the respective year. Arctic sea ice was at a record daily low extent on December 29, 2024.

The image on the right, adapted from NSIDC.org, shows that Arctic sea ice extent was 12.195 million million km² on December 30, 2024, a record low for this date.

The record low daily Arctic sea ice volume and extent occur under La Niña conditions that suppress temperatures. 

As said, as La Niña will gradually decline in the course of 2025 (as predicted), the suppressing impact that La Niña has on temperatures will disappear and the prospect for a steep temperature rise can be expected to become more manifest, with rapid decline of Arctic sea ice constituting just one out of many feedback mechanisms further accelerating the temperature rise.

Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.



Links



• Recent global temperature surge intensified by record-low planetary albedo - by Helge Goessling et al.
https://www.science.org/doi/10.1126/science.adq7280
also discussed on facebook at:
https://www.facebook.com/groups/arcticnews/posts/10162210409914679


• NOAA - ENSO: Recent Evolution, Current Status and Predictions - 30 December 2024 update
also discussed on facebook at:

• NOAA - Monthly Temperature Anomalies Versus El Niño/La Niña
https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202411/supplemental/page-4




• NOAA - Global Monitoring Laboratory - monthly trends in CO2
https://gml.noaa.gov/ccgg/trends/monthly.html


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

• Arctic and Antarctic Data Archive System (ADS) of the National Institute of Polar Research of Japan
https://ads.nipr.ac.jp

• NSIDC - Charctic Interactive Sea Ice Graph

• Cold freshwater lid on North Atlantic
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