Showing posts with label extent. Show all posts
Showing posts with label extent. Show all posts

Saturday, July 5, 2025

Arctic Blue Ocean Event? (update July 2025)


Arctic sea ice extent was 8.35 million km² on July 4, 2025, a record low extent for this time of year. This record daily low extent is the more significant since it was reached in the absence of El Niño conditions. Instead, ENSO-neutral and borderline La Niña conditions are currently dominant.

Sea ice extent is one out of several measurements indicating the miserable state the Arctic sea ice is in, as also discussed in an earlier post. The image below shows Arctic sea ice concentration on July 6, 2025. 

The combination image below shows Arctic sea ice thickness on July 4, 2025 (left) and sea surface temperature on July 5, 2025 (right). 

Arctic sea ice volume was at a record daily low on July 5, 2025, as it has been for more than a year, as illustrated by the image below. 

The global sea ice extent anomaly was -2.98 million km² on July 5, 2025, a standard deviation of -4.81σ, as illustrated by the image below.


Will an Arctic Blue Ocean Event occur in 2025? 
[ from earlier post ]
Most climate models do not anticipate an Arctic Blue Ocean Event (BOE) to occur soon. For such a BOE to occur in 2025 would therefore count as a Black Swan event, i.e. something unexpected. Having said that, there are many things that most climate models didn't expect to occur, including: 

- Very high temperatures, starting in 2023 and still persisting this year 
- Very low Antarctic sea ice over the pasty few years 
- Record high concentrations of greenhouse gases 
- Heat rising from the Southern Ocean into the atmosphere, as discussed in an earlier post 
- Record low Earth's albedo (as illustrated by the image below) 

[ Earth's albedo, image from Eliot Jacobson ]


[ James Hansen: Inferred contributions
to reduced Earth albedo ]
The image on the right, from an earlier post, shows inferred contributions to this drop in albedo, by Hansen et al.

There is a compound impact in that sea ice loss comes with albedo loss that causes more heat to be absorbed by oceans, while higher global sea surface temperatures also cause further loss of lower clouds, further reducing albedo and thus accelerating the temperature rise.

Polar amplification of the temperature rise narrows the temperature difference between the poles and the Equator, which causes distortion of the Jet Stream that in turn results in more extreme weather events. A 2025 study led by Tselioudis suggests that this causes the band of clouds over the Tropics to contract. Since clouds over the Tropics reflect relatively more sunlight, this results in reduced global albedo.

The extraordinary albedo loss depicted in the above image causes the temperature to rise, increasing the probability for a Blue Ocean Event to occur in the course of 2025. 

2024 temperature anomaly: an 11.157σ event




Talking about probabilities, the 2024 world 2m temperature standard deviation from 1951-1980 was very high, an anomaly of 11.157 σ, as illustrated by the above image. In statistics, the empirical rule states that in a normal distribution, 68% of the observed data will occur within one standard deviation (σ), 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. The 2024 temperature anomaly was an 11.157σ event.
Danger Assessment
[ image from earlier post ]
The very continuation of life on Earth is at stake and the sheer potential that all life on Earth may be condemned to disappear due to a refusal by some people to do the right thing, that should prompt the whole world into rapid and dramatic climate action.

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

• National Institute of Polar Research Japan
https://ads.nipr.ac.jp

• Nullschool.net

• University of Bremen

• Kevin Pluck - sea ice visuals

• Climate Reanalyzer

• Heads in the clouds while Earth is burning

• Saltier water, less sea ice

• Arctic Blue Ocean Event 2025? (update June 2025)
• 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, February 3, 2025

Sea ice loss

Global sea ice area was 13.00 million km² on February 9, 2025, a deviation (1981-2000 base) of -5.75 σ and the lowest area on record, as illustrated by the image below, adapted from seaice.visuals.earth.


What is the difference between sea ice area and extent? Extent is the total region with at least 15% sea ice cover. Extent can include holes or cracks in the sea ice and melt ponds on top of the ice, all having a darker color than ice. Sea ice area is the total region covered by ice alone. 

Therefore, sea ice area is a critical measure in regard to albedo. Loss of sea ice area is a self-reinforcing feedback that causes the temperature to rise, resulting in further melting of sea ice, thus accelerating the temperature rise. 

A Blue Ocean Event is often defined as crossing a tipping point that is crossed when sea ice falls below 1 million km² in extent. Doesn't it make more sense to look at sea ice area, rather than at sea ice extent?

Loss of albedo as a result of loss in sea ice is only one out of many feedbacks that come with rising temperatures, as described at the Threat. 

Antarctic sea ice

There are many mechanisms that are driving up, if not accelerating the temperature rise and loss of sea ice.  

As illustrated by the image below, Antarctic sea ice area was 1.05 million km² on February 22, 2023, and was 1.39 million km² on February 9, 2025. Will there be a Double Blue Ocean Event 2025? 


Sea ice thickness is another important measure. The image below shows Antarctic sea ice thickness on four different dates, including February 4, 2025, from the University of Bremen.


The image below shows Antarctic sea ice thickness on February 7, 2025.
For a comparison of Antarctic sea ice thickness at earlier dates, also have a look at this earlier post. 

Arctic sea ice

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 and further accelerating the temperature rise.

[ from the earlier post Double Blue Ocean Event 2025? and discussed here ]

The image below shows Arctic sea ice extent up to February 8, 2025. During the first few months of the year, Arctic sea ice extent is growing, but this recently stopped and extent was at a record low for the time of year on February 8, 2025, despite La Niña conditions. The red line and red marker shows 2025 sea ice. Dots mark sea ice extent on February 8 for the respective year. 


As said, extent is only one way the sea ice can be measured; another way is to measure sea ice area. Furthermore, 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.

[ from earlier post ]

[ Arctic sea ice volume, click to enlarge ]
The image on the right shows Arctic sea ice volume up to February 10, 2025. Arctic sea ice volume in 2024 and 2025 has been much lower than in previous years. 

More incoming heat therefore threatens to reach the seafloor of the Arctic Ocean and destabilize methane hydrates contained in sediments at the seafloor, resulting in eruptions of huge amounts of methane, as illustrated by the above image.

Following the influx of ocean heat from the North Atlantic into the Arctic Ocean, methane peaks above 2400 ppb were recorded by three different satellites, as illustrated by the image below, i.e.
2413 ppb at 399.1 mb by the N20 satellite on February 2, 2025 (left), 
2469 ppb at 399.1 mb by the N21 satellite on February 2, 2025 (center), and 
2446 ppb at 487.2 mb by the Metop-C satellite on February 3, 2025 (right). 

[ Methane peaks above 2400 ppb on Feb 2 & 3, 2025, click to enlarge ]
Arctic temperature rise

The image below shows that the Arctic temperature, i.e. at latitudes higher than 80°N, on February 6, 2025, was much higher than the mean temperature for the period 1959-2002. 

As said before, rising temperatures come with many feedbacks, such as albedo loss and loss of the latent heat buffer. Feedbacks can contribute strongly to further acceleration of the temperature rise. Another feedback is more water vapor ending up in the atmosphere, as illustrated by the image below.

[ from earlier post ]
The above image shows the average daily precipitable water anomaly on February 2, 2025. More water vapor is another self-reinforcing feedback, since water vapor is a potent greenhouse gas that further accelerates the temperature rise.

A new El Niño may emerge in the course of 2025, while Arctic sea ice extent, area thickness and volume are all at record low, while numerous self-reinforcing feedbacks are kicking in with accelerating ferocity and while further mechanisms are accelerating the temperature rise, such as high sunspots and reductions in cooling aerosols, which could lead to a huge temperature rise and an Arctic Blue Ocean Event in 2025, threatening huge amounts of methane to erupt from the seafloor — yet another feedback that comes with rising temperatures.

Ominously, very high temperature anomalies are forecast over the Arctic Ocean for November 2025. 

[ Very high temperature anomalies forecast over Arctic Ocean, click to enlarge ]

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

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

• NSIDC - What is the difference between sea ice area and extent?

• Albedo, latent heat, insolation and more
https://arctic-news.blogspot.com/p/albedo.html

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

• Heat flux forecast to enter Arctic early February 2025
https://arctic-news.blogspot.com/2025/01/heat-flux-forecast-to-enter-arctic-early-february-2025.html

• Danish Meteorological Institute - daily temperature Arctic
https://ocean.dmi.dk/arctic/meant80n.uk.php

• 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

• Climate Reanalyzer
https://climatereanalyzer.org

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

• Tropical Tidbits
https://www.tropicaltidbits.com

• 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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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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