Saturday, October 26, 2024

Models downplay wrath of what they sow

Models that analyze what is driving up the temperature all too often omit specific sources, or when included, models all too often downplay their contribution. Accordingly, policies that are promoted based on such models are all too often ineffective or even counter-productive. 

Methane is all too often referred to as 'natural gas' originating from wetlands, swamps, cows and pigs, as if calling methane 'natural' implied that human activities were not responsible for such emissions. Moreover, people with vested interests all too often suggest that such 'natural emissions' should be captured and used for heating, cooking or industrial purposes, to offset 'human emissions'. Similarly, forest fires are all too often referred to as 'wildfires', as if human activities were not responsible for them. 

The compilation of images below shows forest fires as the largest source of carbon dioxide emissions on October 26, 2024. An image of carbon monoxide is also added (bottom right), as carbon monoxide is an indicator of forest fires. Carbon monoxide is also important since it is a precursor of tropospheric ozone and carbon monoxide depletes tropospheric hydroxyl radicals, thus extending methane's lifetime. 


The methane image (top right) shows a high presence of methane in northern Europe. The cause for this is the high temperatures anomaly in northern Europe on October 26, 2024, resulting in strong decomposition of vegetation, which comes with high emissions of carbon dioxide, carbon monoxide and methane. 


The high temperatures anomaly in northern Europe is illustrated by the above image. The image also illustrates polar amplification of the temperature rise, one of the mechanisms that drives up the temperature rise. Numerous mechanisms driving up the temperature rise are discussed in an earlier post that warns about a Double Blue Ocean Event. Thawing permafrost can cause huge emissions of carbon dioxide (CO₂), methane and nitrous oxide. 

The image below, from an earlier post, shows an added trend that is based on August 2009 through July 2024 data. If this trend continues, 1200 ppm CO₂ could be crossed in early 2035. In other words, the clouds tipping point could get crossed in early 2035 due to rising CO₂ alone, and because this tipping point is measured in CO₂e, this could occur well before 2035 when including the impact of further forcers.


[ from earlier post ]
Rising emissions could originate from many sources, the more so as more sinks turn into sources.
[ from earlier post ]

Climate Emergency Declaration

Instead of omitting such emissions, all mechanisms driving up the temperature should be fully included in any action plan that seeks to improve the situation. Multiple policy instruments and combinations of policy instruments should be considered for implementation, preferably through local feebates. 

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

• Copernicus - Climate Pulse
https://atmosphere.climate.copernicus.eu

• Climate Reanalyzer 
https://climatereanalyzer.org

• Double Blue Ocean Event 2025? 



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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 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 on 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

Global sea ice extent at record low for time of year

Low global sea ice is driving up global temperatures at the moment, in multiple ways, as discussed further below.

On October 17, 2024, global sea ice extent was 22.03 million km², a record low for the time of year. Global sea ice extent is now several million km² lower than it was decades ago, i.e. more than 2.5 million km² lower than the 2010's average extent and more than 5 million km² lower than the 1980's average extent. 

[ click on images to enlarge ]

Antarctic Sea ice thickness and volume

There are indications that Antarctic sea ice volume is already decreasing. The images by University of Bremen below show sea ice thickness on August 27, 2024 (left), September 29, 2024 (center) and October 5, 2024 (right).

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 image below, adapted from Copernicus, illustrates that for most of the year, temperatures in 2024 have been higher than in 2023. The temperature was 15.06°C on October 24, 2024, a record high for the time of year. 


The image below, based on ERA5 data from early 2023 through October 25, 2024, indicates that, overall, temperature anomalies have been rising strongly since the start of El Niño, a rise that has continued during ENSO-neutral conditions into La Niña. 


Note that the above anomalies are calculated from 1991-2020, which isn't pre-industrial. When using a pre-industrial base, temperature 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, and even more when compared to a pre-industrial base. The red line shows the trend (2-year Lowess Smoothing) associated with the rapid recent rise.

Mechanisms accelerating the temperature rise

As illustrated by the image below, there are at least seven mechanisms that are accelerating the surface temperatures rise, and therefore are 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, wind patterns and ocean currents, 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 ]

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 impacts 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.

A 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.


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. 

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, then 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 (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

• 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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Sunday, September 22, 2024

High temperatures despite La Niña?


[ click on images to enlarge ]
Temperatures remain extremely high, even though La Niña conditions may already be present, as illustrated by the above image, showing sea surface temperature anomalies (SSTA) versus 1981-2011. 

The image on the right shows the Northern Hemisphere (-90°,90°) with SSTA as high as 24.8°F (13.8°C) in Hudson Bay (green circle) on Sep. 22, 2024. There are only very few cold spots, while massive amounts of ocean heat are present in the North Atlantic and the North Pacific. 

On September 26, 2024, the sea surface temperature (60°S-60°N, 0-360°E) was 20.97°C, a record high for the time of year and 0.83°C above the 1982-2010 average, as illustrated by the image below. 


North Atlantic (0-60°N 0-80°W) sea surface temperature anomalies remained high and reached a record high for the time of year on September 26, 2024, as illustrated by the image below (SSTA vs 1882-2011).


The image below shows that the North Atlantic sea surface reached a temperature of 24.97°C (76.95°F) on September 22, 2024, a record high for the time of year and 1.07°C (1.926°F) above 1991-2020 or 1.3°C (2.34°F) above 1981-2010. The image also shows a 0.23°C difference in anomalies when shifting the base by a decade, indicating that the anomaly would be much higher when calculated from a pre-industral base. 
 

The image below, by Brian McNoldy shows that ocean heat content in the Gulf of Mexico was at a record high for the time of year on September 23, 2024. 


La Niña conditions may already be present

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, adapted from NOAA, illustrates that El Niño conditions were present from June 2023 through April 2024, and that ENSO-neutral started in May 2024.


While El Niños typically occur every 3 to 5 years, as NOAA explains, El Niños can occur as frequently as every two years, as happened in 2002, 2004 and 2006, as the above image shows. 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.

The danger is that we could move into a new El Niño in 2025, while sunspots move toward a peak and while temperatures remain high due to Earth's high Energy Imbalance and due to feedbacks, as discussed in a recent post. The peak in sunspots in this cycle is expected to occur in July 2025, at which time Arctic sea ice may disappear, triggering further feedbacks, leading to a huge temperature rise by end 2026 that could drive humans into extinction. 


The above image from Copernicus illustrates that, for many months, the temperature anomaly has been high, i.e. about 0.8°C (± 0.3°C) above the 1991-2020 average and much more when compared to a pre-industrial base, with little or no sign of a return to earlier temperatures.


The above image illustrates that global daily mean near-surface (2m) air temperature anomalies vs 1991-2020 (Copernicus) have been above about 0.5°C for almost 16 consecutive months, i.e. since El Niño started (in June 2023, blue shade) and under ENSO-neutral conditions (starting May 2024). La Niña is expected to start October 2024 and the added trends point at a continued rise.   

The danger of methane hydrates getting destabilized

[ click on images to enlarge ]
The image on the right shows sea surface temperatures as high as 32.6°C on September 21, 2024. The image also shows the Gulf Stream pushing ocean heat toward the Arctic Ocean.

This flow of ocean heat can be accelerated by storms that are amplified due to high sea surface temperatures, deformation of the Jet Stream and a freshwater lid forming at the surface of the North Atlantic. 

At the same time, Arctic sea ice starts expanding rapidly in extent at this time of year, effectively sealing off the Arctic Ocean and making it hard for heat to get transferred from the surface of the Arctic Ocean to the atmosphere. 

As discussed in earlier posts, Arctic sea ice has become very thin, diminishing its capacity to act as a buffer that consumes ocean heat entering the Arctic Ocean from the North Atlantic. 

Sea ice constitutes a latent heat buffer, consuming incoming heat as it melts. While the ice is melting, all energy (at 334 J/g) goes into changing ice into water and the temperature remains the same. Once all ice has turned into water, all subsequent energy goes into heating up the water, and will do so at 4.18 J/g for every 1°C the temperature of the water rises.

[ The Latent Heat Buffer ]
Ocean heat that was previously consumed by melting the sea ice, can no longer get consumed by melting of the sea ice once Arctic sea ice has become very thin, and further incoming heat instead gets absorbed by the Arctic Ocean, rapidly pushing up the temperature of the water of the Arctic Ocean.

The danger is that, as the water of the Arctic Ocean keeps heating up, more heat will reach the seafloor and destabilize methane hydrates contained in sediments at the seafloor, resulting in eruptions of huge amounts of methane. 

The image below illustrates how incoming ocean heat that previously was consumed in the process of melting of the sea ice, is now causing the water of the Arctic Ocean to heat up, with more heat reaching the seafloor of the Arctic Ocean, which has seas that in many places are very shallow.
[ Latent heat loss, feedback #14 on the Feedbacks page ]

Eruptions from hydrates occur at great force, since the methane expands 160 times in volume when it vaporizes, resulting in the methane rapidly rising in the form of plumes, leaving little or no opportunity for microbes to decompose the methane in the water column, which especially applies to the many areas where the Arctic Ocean is very shallow. Furthermore, the atmosphere over the Arctic contains very little hydroxyl, resulting in methane persisting in the air over the Arctic much longer than elsewhere.

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

• Nullschool
https://earth.nullschool.net

• Climate Reanalyzer
https://climatereanalyzer.org

• Ocean Heat Content - by Brian McNoldy
https://bmcnoldy.earth.miami.edu/tropics/ohc

• 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





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