Showing posts with label albedo. Show all posts
Showing posts with label albedo. Show all posts

Monday, June 2, 2025

Arctic Blue Ocean Event 2025? (update June 2025)

High temperatures

The image below shows the temperature anomaly (versus 1951-19801) for May 2025. The large difference in anomalies on and around Antarctica is striking, highlighting the predicament of the West Antarctic Ice Sheet.   


How large is the temperature rise now? In the image below, created with NASA data, the decade from 1903 through 1912 is used as a custom base, illustrating that temperature anomalies were 1.5°C or more above this base for the past two years, i.e. for each of the 24 consecutive months from June 2023 through May 2025. So, when using 1903-1912 as a reference, the temperature rise has clearly breached the 1.5°C threshold for the averaging period going back two years through May 2025. What is the best reference period or base against which the rise is to be measured? An earlier analysis suggests that the rise may be even higher when compared to a genuinely pre-industrial base. What averaging period is most appropriate in analyses that include the temperature rise to come? The issue is discussed below. 

  
In the above image, the red line (two-year Lowess Smoothing trend) shows a steep rise that, when extended, points at 2°C above this base (1903-1911) getting crossed in late 2026, implying both goals of the Paris Agreement have been breached, i.e. to limit the temperature increase to 1.5°C above pre-industrial and to limit it to well below 2°C. What type of trend is most appropriate in analyses that include the temperature rise to come? Using a Lowess Smoothing trend and extending that trend linearly into the future may not be the most appropriate way to go. 

The image below shows a polynomial trend, calculated over data from 24 months ago (June 2023) through May 2025, and extended 24 months into the future. It's a cubic trend indicating that the temperature rise may be 3°C in 2026 and 5°C in 2027. 
[ A 3°C rise in 2026 and a 5°C rise in 2027? - click on images to enlarge ] 
How bad could 3°C or 5°C be? The image below adds some perspective, it is from the 2019 post When Will We Die?


Would things look much better when calculating the temperature rise over a longer period?

When using only past data, the average anomaly for the period starting 12 months ago through May 2025 is 1.67°C, for the period starting 24 months ago through May 2025 it is 1.69°C. When using an averaging period starting 10 years ago through May 2025, the average rise is 1.41°C. 

Going back further in time can reduce the average, but such an analysis would incorporate unacceptable bias toward past data at the expense of the rise to come. Indeed, the rise to come should not be ignored by selecting an averaging period that only uses past data. Instead, it makes sense to look at both past data and projections into the future and to also take into account potential acceleration of the rise due to compound impact of feedbacks and further mechanisms, as discussed further below.

The image below uses a 20-year averaging period centered around the end of May 2025. If the temperature rise followed a cubic trend based on data going back one decade, the rise averaged over the entire period would be 5.79°C, while the rise would cross 5°C in late 2031 and would cross 8°C at the end of 2034.
[ click on images to enlarge ]
What if an even longer averaging period was used? In the image below, the inset is added to confirm that the temperature rise vs 1903-1912 has been 1.5°C or higher for each of the past 24 months. The trend in the image covers a 30-year averaging period, centered around the end of May 2025. The trend confirms indications that the temperature rise would be high and cross 8°C in 2037 and 10°C in 2039.
[ click on images to enlarge ]
In other words, the longer the averaging period, the more the trend will be based on (and may be biased toward) data going further back in the past when temperatures were lower and feedbacks were weaker. As temperatures rise over time, however, feedbacks are likely to get stronger. Furthermore, tipping points may get crossed and Black Swan Events may occur. As an example, crossing the clouds tipping point at 1200 ppm CO₂ could - on its own - push temperatures up by an additional 8°C globally, which may occur well before 2028 (as discussed further below) and such tipping points should not be ignored. Indeed, much depends on the strength and combined impact of feedbacks and further mechanisms that could accelerate the temperature rise, so the more reason to discuss them in more detail. 

There are many conditions contributing to even higher temperatures. Emissions and temperatures have recently been rising at a rate that is unprecedented in history. The temperature rise may accelerate further and there are many conditions, feedbacks and further mechanisms that point at further acceleration.  

Earth's Energy Imbalance has more than doubled in recent decades, and reached 1.8 W/m⁻² in 2023, twice the "best" estimate from the IPCC, after having more than doubled within just two decades, as illustrated by the image below, from Mauritsen, 2025).


Below is a video in which Paul Beckwith discusses the study led by Mauritsen. Paul's video has the title: 57 scientists (@46 institutions) co-author 4-page paper ignoring almost all James Hansen's EEI work. James Hansen attributes 1.05 W/m² of the albedo loss to the clouds feedback, 0.15 W/m² to the snow/ice feedback and 0.5 W/m² to changes in shipping regulations (aerosol forcing). James Hansen blames the IPCC for failing to warn about the impact of many feedbacks and further mechanisms that are causing albedo loss. Indeed, the IPCC keeps downplaying the dangers in many ways, such as by ignoring a potentially much higher historic temperature rise and rise to come. Paul Beckwith highlights that the 57 authors of the study are merely calling for a "robust and reliable capability to observe the energy imbalance", without calling for more effective climate action that includes an overhaul of the IPCC narrative.


Concentrations and emissions of greenhouse gases are high and rising. The image below shows recent carbon dioxide (CO₂) concentrations at Mauna Loa, Hawaii.


The image below shows monthly CO₂ at Mauna Loa, Hawaii.


Black Swan Event 1. Crossing the clouds tipping point

The image below shows the same monthly data, this time from May 2022 through May 2025, with a trend added that warns about 1200 parts per million (ppm) getting crossed in 2028. 

Crossing the clouds tipping point at 1200 ppm CO₂ could - on its own - push temperatures up by 8°C globally, in addition to the temperature rise caused by the extra CO₂ to reach the tipping point. Moreover, the clouds tipping point is actually at 1200 ppm CO₂e (carbon dioxide equivalent), so when taking into account the impact of growth of other gases, strengthening feedbacks and further mechanisms, this tipping point could be crossed much earlier than in 2028, potentially as early as in 2026. 

Crossing the clouds tipping point early could be regarded as a Black Swan Event. Black Swan Events are events that are unforeseen in climate models. Such events can suddenly and unexpectedly increase temperatures. While there have been many warnings about such events, they are typically ignored or minimized in climate models. In fact, many warnings about acceleration of the temperature rise are ignored in climate models. Ten black swan events are identified in this post. Since black swan events are inherently unforeseen in climate models, there is little or no discussion about them and there may be many more of them on the way than the ten that are mentioned here.

The situation is also dire regarding other conditions, i.e. concentrations and emissions other than CO₂ are also higher for further gases and aerosols (also fueled by fires and war), while sea ice is low, the Jet Stream is distorted, AMOC is slowing down and sunspots are high.

On top of this, there are numerous self-amplifying feedbacks that can dramatically accelerate the temperature rise and mechanisms are in progress that increase temperatures, such as reductions of aerosols that are currently masking the temperature rise. Not only are many of the feedbacks self-amplifying, strengthening feedbacks and changing conditions can also amplify each other, e.g. a freshwater lid can form at the surface of the North Atlantic and a distorted Jet Stream can combine with hurricanes to cause more ocean heat to get pushed toward the Arctic Ocean underneath this lid, and subsequently speed up sea ice loss and cause eruptions of methane from the seafloor of the Arctic Ocean.
[ formation of a freshwater lid at the surface of the North Atlantic ]
There are further tipping points, in addition to the above-mentioned clouds tipping point. Tipping points include loss of Arctic sea ice and loss of the latent heat buffer as Arctic sea ice disappears; crossing such tipping points can abruptly and strongly increase temperatures and thus trigger crossing of further tipping points. 

Black Swan Event 2. Early El Niño

Models do not predict the next El Niño to appear soon, as illustrated by the image below. Instead, NOAA expects La Niña to return in the Northern Hemisphere fall and winter 2025-26. 


Nevertheless, the next El Niño may emerge earlier, and it may be a strong El Niño. Over the past few months, there's been a zigzag pattern of rises and falls in sea surface temperatures in Niño 3.4, an area in the Pacific (inset) that is critical to the development of El Niño, as illustrated by the image below.


Black Swan Event 3. Low sea ice

One feedback of high temperatures and high concentrations of greenhouse gases is loss of sea ice. Polar amplification of the temperature rise is hitting the Arctic hard, and is also causing dramatic loss of Antarctic sea ice. Global sea ice area has been very low over the past few years, as illustrated by the image below, something that wasn't anticipated in climate models. Low global sea ice comes with dramatic loss of albedo, i.e. a lot of sunlight was in previous years reflected back into space and it is now instead getting absorbed by the sea surface. On June 2, 2025, global sea ice area was 17.52 million km², lowest on record for the day. 


Arctic sea ice extent is currently lowest on record for the day, as illustrated by the image below. On June 16, 2025, Arctic sea ice extent was 10.653 million km², lowest on record for the day.


Low sea ice can also be regarded as a Black Swan Event, the more so since there currently is no El Niño present, but instead ENSO-neutral conditions dominate. Importantly, low sea ice does increase ocean heat, as discussed next. 

Black Swan Event 4. Loss of lower clouds

Low global sea ice area comes with albedo loss and this causes more heat to be absorbed by oceans. Higher sea surface temperatures result in loss of lower clouds, further reducing albedo and thus accelerating the temperature rise. 


This extraordinary loss of albedo may result in a Blue Ocean Event in the course of 2025, as discussed next.

Black Swan Event 5. Blue Ocean Event 

On June 2, 2025, Arctic sea ice area was 2nd lowest on record for that day, only slightly higher than 2016. Significantly, 2016 was a strong El Niño year. On June 2, 2025, Arctic sea ice area was 0.44 million km² lower than on June 2, 2012. If the sea ice area will be 1.34 million km² less than 2012 on September 12 this year, there will be a Blue Ocean Event.  
[ from earlier post ]
Black Swan Event 6. Loss of latent heat buffer

Volume and thickness are two further measures to assess the health of Arctic sea ice, and they are critical in regard to the latent heat buffer, which decreases as sea ice, permafrost and glaciers disappear.

Latent heat is energy associated with a phase change, such as the energy consumed when ice turns into water. During a phase change, the temperature remains constant. As long as there is ice, additional heat will be absorbed by the process of ice turning into water, so the temperature doesn't rise at the surface.

[ from Albedo, latent heat, insolation and more ]
     [ Arctic sea ice volume, click to enlarge ]
The amount of energy absorbed by melting ice is as much as it takes to heat an equivalent mass of water from zero to 80°C. The energy required to melt a volume of ice can raise the temperature of the same volume of rock by as much as 150ºC.

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. 

     [ Arctic sea ice volume, click to enlarge ]
Similarly, there is a point beyond which thawing of permafrost on land and melting of glaciers can no longer consume heat, and all further heat will instead warm up the surface.

The image on the right shows that Arctic sea ice volume has been at a record daily low for more than a year, reflecting severe loss of the latent heat buffer.

Loss of the latent heat buffer constitutes a tipping point. Beyond a certain point, further ocean heat arriving in the Arctic Ocean from the Atlantic Ocean and the Pacific Ocean will no longer be able to be consumed by melting sea ice from below.

The combination image below shows Arctic sea ice thickness on April 28, 2025 (left), May 13, 2025 (center) and June 13, 2025 (right).

[ Arctic sea ice thickness, click on images to enlarge ]
The image below shows Arctic sea ice thickness on June 15, 2025. 
Black Swan Event 7. Seafloor methane eruptions

Further incoming heat therefore threatens to instead reach the seafloor of the Arctic Ocean and destabilize methane hydrates contained in sediments at the seafloor, resulting in abrupt eruptions of huge amounts of methane, in turn threatening increased loss of permafrost, resulting in additional emissions, as illustrated by the above image and the image below. 
[ The Buffer is gone, from earlier post, click to enlarge ]
The danger is especially large in the East Siberian Arctic Shelf (ESAS), which contains huge amounts of methane and which is hit strongly by the temperature rise, as described in earlier posts such as this one.

Methane in the atmosphere could be doubled in March 2026 if a trend unfolds as depicted in the image below. A rapid rise is highlighted in the inset and reflected in the trend, which is based on January 2023-October 2024 methane data, as issued in February 2025. 
[ Double the methane in March 2026? Image from earlier post, click on images to enlarge ]
A rise like the one depicted in the trend could eventuate as rising ocean heat destabilizes methane hydrates contained in sediments at the seafloor of the Arctic Ocean. The temperature rise in the Arctic would accelerate since the methane would initially have a huge impact over the Arctic and cause depletion of hydroxyl, of which there is very little in the atmosphere over the Arctic in the first place. Such a rise in methane would also dramatically increase concentrations of ozone in the troposphere and concentrations of water vapor in the stratosphere. 

The image below with high levels of methane recorded at Utqiagvik (Barrow), Alaska, should act as a warning. 
Black Swan Event 8. Water vapor

The IPCC has failed to warn about the size of the temperature rise. Higher temperatures imply stronger feedbacks, such as stronger evaporation resulting in both a lot more water vapor and a lot more heat getting transferred from the surface to the atmosphere. Much of this will return to the surface with precipitation such as rain and snow, but 7% more water vapor will end up in the atmosphere for every degree Celsius rise in temperature. Moreover, water vapor is a potent greenhouse gas that will increase temperatures and it is a self-amplifying feedback that can strongly contribute to further acceleration of the temperature rise.

[ from April 2024 post, click on images to enlarge ]
As illustrated by the above image, the temperature rise from pre-industrial to February 2024 could be as large as 2.75°C, which corresponds with almost ⅕ more water vapor in the atmosphere. 

Water that previously remained present in the ground, is increasingly moving up into the atmosphere, since a warming atmosphere holds more water vapor and thus sucks up increasingly more water. The water vapor feedback results in more moisture getting sucked up into the air as temperatures rise, a process that is further accelerated by stronger wind as temperatures rise.

More transpiration from vegetation and more evaporation from rivers, lakes and the soil contributes to stronger drought and makes vegetation more vulnerable to pests & diseases and also makes both vegetation and the soil more prone to get burned. After fires, the soils turns black (reflecting less sunlight back into space) and is more vulnerable to erosion and to further droughts and fires, having lost the vegetation that previously held the soil together.

Trees keep the soil together with their roots and also keep the soil cool. Because of the lower temperatures, the soil will also retain more moisture. Trees cool the surface by shading it, by transpiration and by releasing volatile organic compounds into the air that contribute to the formation of clouds that reflect more sunlight back into space and that cause more rainfall. If rainwater can run deep down into the soil along the roots of trees, it helps replenish the groundwater.

The Land Evaporation Tipping Point can get crossed locally when water is no longer available locally for further evapotranspiration, i.e. from all processes by which water moves from the land surface to the atmosphere via evaporation and transpiration, including transpiration from vegetation, evaporation from the soil surface, from the capillary fringe of the groundwater table, and from water bodies on land.

Once this tipping point gets crossed, the land and atmosphere will heat up strongly. Additionally, more water vapor in the atmosphere accelerates the temperature rise, since water vapor is a potent greenhouse gas and this also contributes to speeding up the temperature rise of the atmosphere.
(discussed on facebook here, here and here).

Compound effect of several ignored Black Swan Events 

Black Swan Events may be unexpected and they are typically excluded from models that seek to downplay the dangers, but that doesn't mean that Black Swan Events should be ignored. Using non-linear trends may show unexpected things, but sometimes they can turn out - in hindsight - to be pretty accurate, as illustrated by the combination image below. 
[ screenshot from earlier post, click to enlarge ]
Several Black Swan Events can also combine with catastrophic results, as described below. 

Black Swan Event 9. Abrupt collapse of the West-Antarctic ice sheet

A recent study warns that collapse of the West Antarctic Ice Sheet (WAIS) could contribute over 4 m sea-level rise with little (0.25 °C) or even no ocean warming above present, even without additional carbon emissions. The study concludes that we are likely already at (or almost at) an overshoot scenario and adds that, once on the lower branch, WAIS recovery by tipping back to the upper branch occurs only once the ocean temperature cools between −1.25 and −1.5 °C below present.

In the video below, Paul Beckwith discusses the study. 


The very low Antarctic Sea Ice over the past few years was not anticipated by models, neither was the steep rise in sea surface temperatures. Continued loss of Antarctic sea ice could dramatically increase sea surface temperatures where the sea ice disappears. A further rise of global sea surface temperatures could make things worse. The joint impact could cause abrupt collapse of the West Antarctic Ice Sheet.

Black Swan Event 10. Fires and lightning

Emissions can increase strongly, abruptly and rapidly for many reasons, such as due to more burning of fossil fuel, forests, wood and other biofuel, and more vegetation starting to die due to droughts, heatwaves, pests and diseases, and decompose or burn due to fires. Peatlands, tar sands, rainforests and soil can all start to burn as temperatures keep rising. As temperatures rise rapidly, permafrost can release huge amounts of emissions, including carbon dioxide, methane and nitrous oxide.


The above image shows annual number of fires and area burned in Canada and is adapted from the Canadian National Fire Database, which adds that while lightning causes about 50% of all fires, it accounts for about 85% of the annual area burned. A 2022 study finds that increases in lightning ignition efficiency, together with a projected doubling of lightning strikes, result in a 39%–65% increase in lightning-caused fire occurrence per 1°C warming.

The combination of higher temperatures, stronger wind, higher vulnerability of forests and more lightning will cause more fires and more emissions of carbon dioxide, black carbon, brown carbon, methane, carbon monoxide and tropospheric ozone. At 3-8 miles height, during the summer months, lightning activity increases NOx by as much as 90% and tropospheric ozone by more than 30%. Tropospheric ozone has a direct warming impact as a greenhouse gas, while carbon monoxide can indirectly cause warming by extending the lifetime of methane. 

The worst wildfires can send smoke high enough to affect the ozone layer in the stratosphere. Damage to the ozone layer and climate change are forming a dangerous feedback loop.

Scientists are shocked to see sea ice disappear

In the video below, Guy McPherson reflects on news that scientists are shocked to see sea ice disappear.


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

• NASA - GISS Surface Temperature Analysis

• Earth's Energy Imbalance More Than Doubled in Recent Decades - by Thorsten Mauritsen et al. (2025)
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024AV001636
discussed on Facebook at: 

• NOAA - Daily, Monthly and Weekly Average CO2

• NOAA - Global Monitoring Laboratory

• Clouds Tipping Point
https://arctic-news.blogspot.com/p/clouds-feedback.html

• Arctic Blue Ocean Event 2025?

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

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

• Climate Reanalyzer
https://climatereanalyzer.org

• NOAA - Climate Prediction Center - ENSO: Recent Evolution, Current Status and Predictions
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

• NOAA - Climate Prediction Center - El Niño/Southern Oscillation (ENSO) Diagnostic Discussion
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

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

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

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

• NOAA - Office of Satellite And Product Operations - Sea Surface Temperatures
https://www.ospo.noaa.gov/products/ocean/sst/contour/index.html

• Jet Stream
https://arctic-news.blogspot.com/p/jet-stream.html

• Cold freshwater lid on North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html

• Arctic Blue Ocean Event 2025? 
https://arctic-news.blogspot.com/2025/03/arctic-blue-ocean-event-2025.html

• Accelerating Temperature Rise 
https://arctic-news.blogspot.com/p/threat.html

• Feedbacks (including the Water Vapor Feedback)
https://arctic-news.blogspot.com/2024/07/feedbacks.html

• Extinction
https://arctic-news.blogspot.com/p/extinction.html

• Antarctic Ice Sheet tipping in the last 800,000 years warns of future ice loss - by David Chandler et al. 
https://www.nature.com/articles/s43247-025-02366-2

• Future increases in lightning ignition efficiency and wildfire occurrence expected from drier fuels in boreal forest ecosystems of western North America - by Thomas Hessilt et al. (2022) 









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Friday, October 4, 2024

Double Blue Ocean Event 2025?

A double Blue Ocean Event could occur in 2025. Both Antarctic sea ice and Arctic sea ice could virtually disappear in 2025. A Blue Ocean Event (BOE) occurs when sea ice extent falls to 1 million km² or less, which could occur early 2025 for Antarctic sea ice and in Summer 2025 in the Northern Hemisphere for Arctic sea ice.

Arctic sea ice volume

In September 2024, Arctic sea ice reached a new record low volume, as illustrated by the image below, adapted from the Danish Meteorological Institute, with markers for September (red) and April (blue) corresponding with the year's minimum- and maximum volume.


Trends could be added pointing at Arctic sea ice approaching zero volume soon; even more worrying, tipping points could be crossed and speed up the temperature rise beyond a smooth curve. Feedbacks are typically seen as increasing the temperature gradually and smoothly, either in a linear or non-linear way. Feedbacks are mechanisms, but there are also mechanisms that act more abruptly.

Indeed, some mechanisms can have a more abrupt impact. Sea ice could shrink strongly and rapidly as a (tipping) point is reached where the latent heat buffer disappears abruptly and as further incoming ocean heat suddenly can no longer be consumed by melting of what once was thick sea ice that extended meters below the surface. Arctic sea ice typically reached its annual low about half September, but an abrupt decline of Arctic sea ice may well occur earlier than that. Sea ice may melt strongly, and large pieces of sea ice may additionally get pushed out of the Arctic Basin by strong winds. Large and rapid loss of Arctic sea ice may therefore well occur in July 2025 or even earlier, as the latent heat tipping point gets crossed and additional mechanisms further contribute to increase the temperature.

Antarctic Sea ice extent

Antarctic sea ice extent has passed its maximum for the year, and looks set for a steep decline, in line with seasonal changes.

On October 11, 2024, Antarctic sea ice was more than 1 million km² lower in extent than on October 11, 2022, and almost 3 million km² lower in extent than a decade ago, as illustrated by the image below.


Antarctic sea ice extent was
16.757 million km² on October 11, 2024
17.926 million km² on October 11, 2022
19.412 million km² on October 11, 2014

This difference indicates that sea ice extent may fall below 1 million km² in February 2025.

As illustrated by the image below, Antarctic sea ice extent was 1.976 million on February 25, 2022, so 1 million km² less extent than that would result in a Blue Ocean Event early next year. A Blue Ocean Event is deemed to occur when the sea ice extent falls to 1 million km² or less.

Low Antarctic sea ice extent is a tipping point, as sea ice thickness by February 2025 can be expected to be minimal, resulting in no further ocean heat getting consumed by sea ice below the surface. So, there would be less sunlight getting reflected back into space for months and by February 2025 there would no longer be thicker sea ice that previously consumed incoming ocean heat, and both of these mechanisms are further increasing temperatures.

Note also that Antarctic sea ice extent looks set for a steep decline, the more so as the impact of less sunlight getting reflected will increase over the coming months as more sunlight reaches the Southern Hemisphere, in line with seasonal changes. Albedo changes hit Antarctic sea ice in particular, as it is located at higher latitudes than Arctic sea ice, which is located mostly around the North Pole.

As the image below illustrates, the Antarctic Sea ice extent minimum was well below 2 million km² in each of the past three years.
Minimum annual Antarctic sea ice extent was:
1.976 million km² on February 25, 2022
1.788 million km² on February 21, 2023
1.985 million km² on February 20, 2024

The image below highlights Antarctic sea ice extent in the months September and October, showing NSIDC data from 2010 through November 2, 2024.


As above image shows, Antarctic sea ice extent in September and October 2023 & 2024 was much lower than in previous years, a huge difference that occurred during a period when little or no sunlight was reaching Antarctic sea ice. 

So, what mechanisms caused this huge difference?

Since little or no sunlight reaches the area around Antarctica at this time of year, sea surface albedo changes (i.e. changes from sea ice to water) or albedo changes of clouds over the sea surface are unlikely to contribute much (yet) to this huge difference.

Changes in wind patterns and changes in oceans (temperature, currents, vertical mixing and stratification) can make a lot of difference and so can changes in emissivity, a feedback that is active throughout the entire year. Mechanisms that are contributing to the demise of the snow and ice cover (and thus are contributing to the temperature rise) are discussed point by point further below in this post.  

Global sea ice extent at record low for time of year

Rising global temperatures go hand in hand with lower global sea ice extent. On November 3, 2024, global sea ice extent was 23.15 million km², a record low for the time of year and well below the 2023 extent at this time of year. This record low global sea ice extent is in turn accelerating the rise in global temperatures. Global sea ice typically reaches its annual maximum extent around this time of year, as Arctic sea ice expands in extent. 

[ Click on images to enlarge ]

Antarctic Sea ice thickness and volume

The images by University of Bremen below show sea ice thickness on August 27, 2024 (left), September 29, 2024 (center) and October 28, 2024 (right). The fall in sea ice thickness also indicates that Antarctic sea ice volume is decreasing. 

[ Click on images to enlarge ]

Temperatures keep rising

Temperature anomalies were high in September 2024, while there have been ENSO-neutral conditions since May 2024 through September 2024. Parts of Antarctic sea ice were hit by very high anomalies, of over 10°C, while very little sunlight is yet reaching Antarctic sea ice in September. 


The Copernicus image below illustrates that for most of the year, temperatures in 2024 have been higher than in 2023. The temperature was 14.71°C on November 2, 2024, a record high for the time of year. 

The image below, based on ERA5 data from early 2023 through November 2, 2024, indicates that, overall, temperature anomalies have been rising even before El Niño started, a rise that has continued during El Niño, during ENSO-neutral conditions and into La Niña. 


Note that the above temperature anomalies are calculated from 1991-2020, which isn't pre-industrial. When using a pre-industrial base, the anomalies will be a lot higher.


The above image, created with NASA data through September 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 each of the past consecutive 15 months. The red line shows the trend (2-year Lowess Smoothing) associated with the rapid recent rise.

Note again that the above temperature anomalies are not calculated from pe-industrial, in this case they are calculated from 1903-1924. When using a pre-industrial base, the anomalies will be higher.

Mechanisms accelerating the temperature rise

Emissions by people are driving up temperatures and, as temperatures rise, feedbacks can accelerate the rise. The image below illustrates the mechanism of how multiple feedbacks can jointly accelerate the temperature rise.


[ from earlier post ]

As illustrated by the image below, there are at least seven mechanisms that can accelerate the rise in surface temperatures, and thus in turn accelerating sea ice decline.


Each of these seven mechanisms are feedbacks that are also described at the feedback page and in earlier posts. These seven mechanisms are grouped together here since they all relate to changes in snow and ice cover, changes in oceans and changes in wind patterns, i.e. the orange part of the stacked bar chart at the conclusion of this article. In other words, as temperatures rise on the Southern Hemisphere, these seven mechanisms could contribute to dramatic sea ice loss around Antarctica over the next few months. The are described below in more detail:

1. latent heat buffer loss  ➭  less heat gets consumed by melting (feedback #14)

Sea ice constitutes a buffer that consumes ocean heat; the temperature of the water will not rise as long as there is ice, but once all ice has melted, further heat will raise the temperature of the water. The amount of energy absorbed by melting ice is as much as it takes to heat an equivalent mass of water from zero to 80°C.

[ Latent heat ]

2. sea ice changing into dark ocean  ➭  less sunlight is reflected (feedback #1)
Water covered by snow and ice can reflect as much as 90% of the sunlight back into space, absorbing only 10%. By contrast, water without snow and ice can absorb as much as 94% of sunlight, with as little as 6% reflected back into space.  
A study by Duspayev et al. (2024) finds that global sea ice has lost 13%–15% of its planetary cooling effect since the early/mid 1980s, and the implied global sea ice albedo feedback is 0.24–0.38 W m⁻² K⁻¹.

3. less sea ice  ➭  less outward radiation (feedback #23)

A 2014 study finds significantly lower values of far-IR emissivity for ocean surfaces than for sea ice and snow, leading to a decrease in surface emission at far-IR wavelengths, reduced cooling to space, and warmer radiative surface temperatures.

4. ocean warming  ➭  less lower clouds  ➭  less sunlight reflected (feedback #25)

A 2021 study finds that warming oceans cause fewer bright clouds to reflect sunlight into space, admitting even more energy into Earth's climate system.

[ Earthshine annual albedo anomaly expressed as reflected flux in W/m². CERES data. ] 

The image below highlights the Pattern Effect of the Southern Ocean's committed warming (around -60°S) becoming more manifest over the years, as warming causes low-level clouds to disappear that reflect sunlight back. A 2021 study concludes this could make a difference of 0.7°C.

[ The Pattern Effect could account for a 0.7°C temperature rise. ]

5. ocean warming  ➭  stratification  ➭  less heat reaches deeper waters (feedback #29)

Higher sea surface temperatures come with greater stratification.

[ from earlier post ]

A recent study by Goreau et al. concludes:
Decreased vertical exchange in cold surface currents and in upwelling zones increases thermal stratification and slows down the Atlantic Meridional Overturning Circulation (AMOC), retains heat longer in the surface ocean, and reduces CO₂ exchange among the atmosphere, surface ocean, and the deep sea. The HotSpot maps from year to year suggest that upwelling systems can abruptly shut off, causing sudden sharp rises in regional air temperatures, and reducing air-ocean exchange of temperature and CO₂.

6. ocean currents and wind patterns change  ➭  less heat reaches deeper waters (feedback #19)

[ from earlier post ]
Oceans are still absorbing an estimated 91% of the excess heat energy trapped in the Earth's climate system due to human-caused global warming. If just a small part of that heat instead remains in the atmosphere, this could constitute a huge rise in the  temperature of the lower atmosphere.

Polar amplification of the temperature rise causes a relative slowing down of the speed at which heat flows from the Equator to the poles. This can affect ocean currents and wind patterns, resulting in slowing down of the Atlantic meridional overturning circulation (AMOC) and of ocean currents around Antarctica that carry heat to the deep ocean, as well as in deformation of the Jet Stream.

Another recent study warns about intensification of global warming due to the slowdown of the overturning circulation. The overturning circulation carries carbon dioxide and heat to the deep ocean, where it is stored and hidden from the atmosphere. As the ocean storage capacity is reduced, more carbon dioxide and heat are left in the atmosphere. This feedback accelerates global warming.

7. freshwater lid forms at ocean surface  ➭  more heat reaches Arctic Ocean (feedback #28)

Greater stratification, meltwater and rain can contribute to the formation of a freshwater lid that expands at the surface of the North Atlantic, enabling more ocean heat to travel underneath this lid from the North Atlantic into the Arctic Ocean, which can occur abruptly at times when a deformed Jet Stream causes storms that speed up ocean currents along this path.

8. Further mechanisms

8.1. El Niño and sunspots

Further mechanisms that could accelerate the temperature rise include a new El Niño in 2025, coinciding with a peak in sunspots that is higher than expected. The black dashed line in the image below, adapted from NOAA, indicates a transition to La Niña in October 2024, persisting through Jan-Mar 2025.


The image below shows the October 2024 IRI ENSO forecast. NOAA adds that the IRI plume predicts a weak and a short duration La Niña, as indicated by the Niño-3.4 index values less than -0.5°C.

[ IRI ENSO forecast from Oct 2024 ]

A new El Niño looks set to emerge soon and this may occur in the course of 2025, while Earth's Energy Imbalance is high (and rising), while feedbacks and other mechanisms add further heat and while sunspots reach a peak in this cycle (expected to occur in July 2025), all contributing to further accelerate the temperature rise.

[ click on images to enlarge ]

The above image, adapted from NOAA, illustrates that El Niño conditions were present from June 2023 through April 2024, and that ENSO-neutral conditions were present from May 2024 through September 2024.

8.2. Earth's Energy Imbalance and lack of political will to act

Earth's growing energy imbalance is perhaps the most obvious mechanism that increases the temperature. 


The image below, by Leon Simons, shows Earth's Energy Imbalance to April 2024 (12-month running mean) as the difference between absorbed and outgoing radiation. 


It's obvious that political action can and must improve Earth's Energy Imbalance, which can and must be achieved by reducing greenhouse gas emissions and further action, through transitions in energy use, agriculture, transport, etc. 

The IPCC has for many years weaved and twisted findings by scientists into a political narrative that downplays the temperature rise and refuses to point at the most effective measures to be taken to act on climate change, in an effort to create the illusion that there was a carbon budget to be divided among polluters as if pollution could continue for decades to come.

Lack of political will to act on the climate emergency is perhaps the most depressing mechanism accelerating the temperature rise. Moreover, where action is taken, blunt political instruments are all too often chosen that won't last long or turn out to be counter-productive. 

8.3. Aerosols

A further mechanism that could strongly accelerate the temperature rise is the falling away of the masking effect of aerosols currently emitted jointly with the greenhouse gases produced in the process of burning fossil fuel and biofuel. Blunt measures may be taken to reduce burning of fossil fuel and biofuel, which will reduce greenhouse gas emissions and also reduce emission of cooling aerosols, while such measures can at the same time encourage many to use more wood burners, thus also causing more warming aerosols to be emitted.

Sadly, few people are calling for more sophisticated measures, let alone for more effective measures such as local feebates. It is important to be open and clear as to what can and must be achieved and how, and why.  

Scientist warn that the combined impact of aerosols and nitrogen fertilizers has been underestimated; a recent study concludes that when ammonia, nitric acid and sulfuric acid are present together, they contribute strongly to the formation of cirrus clouds.

The IPCC image below shows how much temperatures are currently suppressed in the Arctic due to aerosols and thus also shows how much temperatures in the Arctic look set to rise as the aerosol masking effect falls away. 


8.4. Water vapor and the importance of the size of the temperature rise

The water vapor feedback is also getting stronger. The image below, created with NOAA data, shows surface precipitable water through September 2024. Note that values in 2024 are higher than in 2023. 

The image below, adapted from Climate Reanalyzer, shows the spread of the September 2024 anomaly in precipitable water, with less over the Amazon, but more over the Sahara, while more also shows up at higher northern latitudes, i.e. over the Barents Sea and the Canadian Arctic Archipelago. 


Since the water vapor feedback roughly follows the temperature rise (7% more water vapor for every 1°C warming), it's important to know the full rise from pre-industrial, as opposed to a rise calculated from a later base. If the temperature rise since pre-industrial is significantly larger, then the extra water wapor feedback will accordingly be larger. 

A lot of the extra water vapor gets into the atmosphere through evaporation from oceans, but a significant part also comes from land and water bodies on land. A lot of energy gets consumed in the process of evaporation from land and lakes and in the process of thawing of permafrost. Water that previously remained present in the ground, is increasingly moving up into the atmosphere. The water vapor feedback results in more moisture getting sucked up into the air as temperatures rise, a process that can be further accelerated by stronger wind as temperatures rise.

The image on the right shows shallow groundwater storage in most of South America for the week of October 7, 2024, as measured by the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) satellites (NASA image, discussed on facebook). 

The image illustrates the danger of the Land Evaporation Tipping Point getting crossed locally when water is no longer available locally for further evapotranspiration, i.e. from all processes by which water moves from the land surface to the atmosphere via evaporation and transpiration, including transpiration from vegetation, evaporation from the soil surface, from the capillary fringe of the groundwater table, and from water bodies on land. Once this tipping point gets crossed, the land and atmosphere will heat up strongly, due to the extra heat, i.e. heat that was previously consumed by evaporation and thawing. Additionally, more water vapor in the atmosphere accelerates the temperature rise, since water vapor is a potent greenhouse gas and this also contributes to speeding up the temperature rise of the atmosphere.

Similarly, the rise to come (over the next few years) could be significantly larger than expected, e.g. due to the above seven mechanisms relating to changes in snow & ice, winds and oceans, in which case the extra water vapor will accordingly be larger. 

The image below shows the global September 2024 sea surface temperature anomaly (versus 1951-1980, ERA5 data, adapted from Climate Reanalyzer). 


The image below shows that the September 2024 sea surface temperature anomaly (versus 1951-1980) was at a record high, in a tie with October 2023, in the area between latitudes 10°North and 40°North. 


The image below shows that the September 2024 total column precipitable water anomaly (versus 1951-1980, ERA5 data) was at a record high in the area between latitudes 10°North and 40°North. 


8.5. Tipping points

Loss of Arctic sea ice and loss of Permafrost in Siberia and North America can be regarded both as feedbacks and as tipping points. Loss of Antarctic sea ice and loss of the snow and ice cover on land elsewhere (on Greenland, on Antarctica and on mountaintops such as the Tibetan Plateau) can also be regarded as tipping points. 

What makes them tipping points is that, once the snow and ice cover has disappeared and the ice in the soil has melted, further heat can no longer be consumed in the process of melting or thawing, resulting in a sudden local temperature rise that spreads to neighboring areas. 

As temperatures keep rising, this could cause a second Blue Ocean Event to occur in 2025, i.e. in the Arctic. Subsequently, as the oceans keep heating up, the seafloor methane tipping point could be crossed. 

The image below lists 14 events. Note that the 14 mechanisms below are from an earlier post and many mechanisms differ from the above 8 mechanisms. Note also that the order may differ and that, instead of one domino tipping over the next one sequentially, many events may occur simultaneously and reinforce each other in the speed at which they unfold and the temperature rise that results. There could be interaction and amplification between mechanisms, resulting in a huge abrupt acceleration of the temperature rise that leads to extinction of most species, including humans, as the image below warns, from an earlier post. Finally, note that there could be Black Swan Events that have not yet been identified. 

[ from earlier post - click on images to enlarge ]

Seven important tipping points are:
- The Latent Heat Tipping Point (feedback #14, as discussed above)
- The Seafloor Methane Tipping Point (feedback #16)
- The Clouds Tipping Point (also clouds feedback #30)
- The Terrestrial Biosphere Temperature Tipping Point
- The Ocean Surface Tipping Point (also discussed at facebook)
- The Land Evaporation Tipping Point (discussed above, also discussed at facebook)
- The Aquatic Deoxygenation Tipping Point (also discussed at facebook)

[ for more background, also view the Extinction page ]
A huge temperature rise could occur soon

A huge temperature rise could occur soon, as the impact of these mechanisms keeps growing, as the latent heat tipping point gets crossed in a Double Blue Ocean Event and the seafloor methane tipping point subsequently gets crossed. 

As temperatures keep rising in the Arctic, changes to the Jet Stream look set to intensify, resulting in loss of terrestrial albedo in the Arctic that could equal the albedo loss resulting from sea ice decline.

Further feedbacks include permafrost degradation, both terrestrial and on the seafloor of the Arctic Ocean, which looks set to cause huge releases of greenhouse gases (particularly CO₂, CH₄ and N₂O).

This would in turn also cause more water vapor to enter the atmosphere, further speeding up the temperature rise. 

The danger of a huge temperature rise is very large in the Arctic, where vast amounts of methane are held in sediments at the seafloor and in permafrost on land, and where there is very little hydroxyl in the air to break down the methane.

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

• Arctic Data archive System - National Institute of Polar Research - Japan
https://ads.nipr.ac.jp/vishop

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

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

• NSIDC - Interactive sea ice chart
https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph

• Climate Reanalyzer

• Copernicus

• Earth's Sea Ice Radiative Effect From 1980 to 2023 - by Duspayev et al. (2024) 
• NOAA - Climate Prediction Center - ENSO: Recent Evolution, Current Status and Predictions
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

• NOAA - Physical Sciences Laboratory
https://psl.noaa.gov

• NASA 
https://data.giss.nasa.gov

• Indicators of Global Climate Change 2023: annual update of key indicators of the state of the climate system and human influence - by Piers Forster et al. 
https://essd.copernicus.org/articles/16/2625/2024

• 2023 Record marine heat waves: coral reef bleaching HotSpot maps reveal global sea surface temperature extremes, coral mortality, and ocean circulation changes - by Thomas Goreau et al. 
https://academic.oup.com/oocc/article/4/1/kgae005/7666987

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

• Jet Stream
https://arctic-news.blogspot.com/p/jet-stream.html

• Freshwater lid on the North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html

• Latent Heat
https://arctic-news.blogspot.com/p/latent-heat.html

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

• Indicators of Global Climate Change 2023: annual update of key indicators of the state of the climate system and human influence - by Piers Forster et al. 


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