Showing posts with label concentration. Show all posts
Showing posts with label concentration. Show all posts

Sunday, August 17, 2025

Dire State of Climate

El Niño may emerge early 2026

On the image below, very high sea surface temperature anomalies (vs 1981-2011) are showing up in the Northern Hemisphere, as high as 17.1°C or 30.8°F in the Gulf of Ob, where the water of the Ob River flows into the Kara Sea (at the location marked by the green circle).

At the same time, water is colder than 1981-2011 in the equatorial Pacific region, causing a La Niña to emerge, which means that current temperatures are actually suppressed.


El Niño-Southern Oscillation (ENSO) is a climate pattern that fluctuates from El Niño to La Niña conditions and back. El Niño raises temperatures, whereas La Niña suppresses temperatures. This year, there have been neutral to borderline La Niña conditions, as illustrated by the image below, which also shows that over the past few months, there has been a zigzag pattern of rises and falls around the mean sea surface temperature in Niño 3.4, an area in the Pacific (inset) that is critical to the development of El Niño. 


The image below shows the July 2025 sea surface temperature anomaly vs 1951-1980. Note the higher than 10°C anomalies in the Kara Sea in the Arctic Ocean (white area, anomalies are compared to 1951-1980).


The image below shows the sea surface temperature anomaly on August 27, 2025, this time versus 1971-2000. Note the large area with high temperature anomalies in the Kara Sea and the colder temperatures in the equatorial Pacific region, indicating that these high temperature anomalies are reached in the absence of El Niño, i.e. temperatures are actually suppressed.


   [ click on images to enlarge ]
As illustrated by the image on the right, the sea surface temperatures of the U.S. North Atlantic were as high as 32.8°C on August 24, 2025, the same peak temperature that was reached on August 5, 2025.

The image shows heat moving north along the path of the Gulf Stream toward the Arctic, threatening to cause more loss of sea ice and permafrost.

Heat naturally flows from hot to cold areas. Furthermore, warm water floats on top of colder water because it is less dense, resulting in stratification. This in combination with the Coriolis effect causes higher sea surface temperatures along the path of the Gulf Stream toward the Arctic, as indicated by water with an orange color on the image. 

Similarly, warm water moves along the path of the Kuroshio Current in the North Pacific. 

[ click on images to enlarge ]
Despite the current absence of El Niño conditions, extreme weather events have hit many areas around the world over the past few months, temperatures have been very high and Arctic sea ice is in a dire state, as illustrated by the images further below.

As illustrated by the image on the right, adapted from NOAA, the ENSO outlook (CFSv2 ensemble mean, black dashed line) favors La Niña during the Northern Hemisphere fall and early winter 2025-2026. 

[ image from earlier post ]
The image on the right, adapted from ECMWF, shows an ENSO forecast for developments in Niño3.4 through August 2026, indicating that the next El Niño may emerge early 2026 and grow in strength in the course of 2026.

High temperatures in absence of El Niño

In the Northern Hemisphere, the 2024 temperature anomaly was 1.701°C higher than the 1951-1980 mean, as discussed in an earlier post. This constitutes a 14.349σ event, as illustrated by the image below.

[ image from earlier post ]
So, what happened in 2025? In the absence of El Niño, one would expect temperatures to fall. However, as illustrated by the image below, monthly temperatures have risen in the Northern Hemisphere, reaching a standard deviation of 10.673 in July 2025 (vs 1951-1980).  


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

As said, the 2024 temperature anomaly in the Northern Hemisphere was a 14.349σ event. Natural variability fails to explain such an anomaly. This year, in the absence of El Niño, monthly deviations from the temperature anomaly have risen in the Northern Hemisphere, reaching a standard deviation of 10.673 in July 2025. This indicates that El Niño alone cannot be blamed for this rise, not even in combination with reductions of the aerosol masking effect. What appears to be driving the acceleration of the temperature rise most strongly is a combination of feedbacks including loss of snow and ice, loss of lower clouds, changes to soil moisture and water vapor in the atmosphere, changes to ocean currents and wind patterns, etc.  

As illustrated by the image below, the temperature in the Arctic (66.5–90°N, 0–360°E) was 4.49°C on August 23, 2025, a record high for that day and an anomaly of +2.54°C versus 1979-2000. The inset shows a map with Arctic temperature anomalies versus 1991-2020 highlighted on August 23, 2025. 


The image below shows a larger version of the inset, with temperatures over the Arctic (66.5–90°N, 0–360°E) highlighted on August 23, 2025. Note that the temperature anomaly also was very high over Antarctica on August 23, 2025. 


Albedo loss

The next El Niño could be catastrophic, given the dire state of the climate, which is getting increasingly dire, as emissions keep rising, albedo keeps falling, and feedbacks keep growing in strength. The fall in albedo is illustrated by the image below, created with an image by Eliot Jacobson.  


The fall in albedo can be attributed to snow and ice decline, reductions in cooling aerosols (Hansen, May 2025) and changes in clouds (Loeb, 2024). Snow and ice decline and changes in clouds are self-amplifying feedbacks that can rapidly and strongly accelerate the temperature rise as well as trigger and amplify further feedbacks.

Snow and ice decline

The image below shows the global sea ice extent anomaly through August 27, 2025, when the global sea ice extent was 2.91 million km² below the 1981-2010 mean, a deviation from 1981-2010 of -3.87σ. 
The global sea ice extent anomaly is far below the 1981-2010 mean and close to the anomalies of 2023 and 2024 that were far outside the 1981-2010 mean at this time of year. That is very worrying, more so given the current absence of El Niño conditions. Also, sea ice area is only one way of looking at the sea ice decline. The data for concentration, thickness and volume of Arctic sea ice make the situation even more worrying, as discussed below.  

Heavy melting is taking place in the Arctic. The image below shows Arctic sea ice concentration on August 26, 2025.

The combination image below compares Arctic sea ice on August 17, 2025, i.e. concentration (left) and thickness (right).


In the panel on the right of the above image, melt pools may give the impression of zero thickness in areas close to the North Pole. Melt pools can indicate that rainfall and/or heavy melting is taking place. 

The image below shows temperature anomalies on August 21, 2025 (left) and on August 22, 2025 (right). As discussed in earlier posts such as this one, in the Northern Hemisphere water evaporates from the sea surface of the North Atlantic and the North Pacific. Prevailing winds carry much water vapor in the direction of the Arctic. Precipitation over the Arctic Ocean freshens the surface, forming a buffer that temporarily slows down the decline of the sea ice extent. Similarly, much of the precipitation over land is carried by rivers into the Arctic Ocean, also freshening the surface of the Arctic Ocean. Furthermore, heavy melting of Arctic sea ice over the past few months has added further freshwater to the surface of the Arctic Ocean. The slowdown of AMOC can also create a buffer by delaying the transport of ocean heat toward the Arctic Ocean. This makes the dire state of Arctic sea ice very significant, even more so since we're in borderline La Niña conditions. Given the increase of Earth's Energy Imbalance and the additional heat that is instead accumulating in the north Pacific and the North Atlantic, more heat looks set to eventually reach the Arctic Ocean, overwhelming such buffers and threatening to cause Arctic sea ice collapse.

[ click on images to enlarge ]
The image below shows the precipitable water anomaly on August 21, 2025 (left) and on August 22, 2025 (right).

[ click on images to enlarge ]
As discussed in earlier posts such as this one, in the Southern Hemisphere water evaporates from the Southern Ocean and part of it falls on the Antarctic ice sheet, thickening the snow layer, as also illustrated by the above image that shows persistently high precipitable water anomalies over Antarctica over the past two days (on August 20, 2025 and on August 21, 2025). As a result, the Southern Ocean surface is getting more salty. As also discussed in an earlier post, saltier surface waters sink more readily, allowing heat from the deep to rise, which can melt Antarctic sea ice from below, even during winter, making it harder for ice to reform. This vertical circulation also draws up more salt from deeper layers, reinforcing the cycle.

The image below shows that Arctic sea ice volume was at a record low for the day on August 26, 2025, as it has been for more than a year. Volume is important, as also discussed on facebook


As the image below shows, Arctic sea ice reached a new record annual low volume in September 2024.

On the image below, markers are added for September (red) and April (blue) corresponding with the year's minimum- and maximum volume, confirming the downward path since 2015 for both the annual sea ice volume minimum and maximum.

Arctic sea ice volume has steadily declined since 2005, as the above measurements by the Danish Meteorological Institute show. Arctic sea ice volume now is less than 5000 km³, about half of what the volume was in 2004-2013.

Absence of thick sea ice makes it prone to collapse, and this raises the question whether it could collapse soon, even this year. Storms could rapidly push the remaining pieces of thicker sea ice out of the Arctic Ocean. Such storms could also mix surface heat all the way down to the seafloor, especially in areas where seas are shallow. 

Methane

[ The Buffer is gone, from Accelerating Temperature Rise ]
Sea ice constitutes a buffer that previously consumed much incoming ocean heat (left); as sea ice thins, the buffer disappears while more heat also enters the Arctic Ocean (right). Further heat entering the Arctic Ocean from the Atlantic Ocean and the Pacific Ocean threatens to destabilize sediments that contain methane, causing eruption of huge amounts of methane.


As temperatures rise, methane concentrations are increasing due to more fires and decomposing organic carbon.

In addition, rising temperatures threaten to destabilize sediments containing vast amounts of methane in the form of hydrates and free gas, causing huge amounts of methane to erupt and enter the atmosphere. Over the Arctic, there is very little hydroxyl in the air, which extends the lifetime of methane over the Arctic. The temperature is already rising much more rapidly in the Arctic than elsewhere in the world, so this would act as a strong self-amplifying feedback.

[ from earlier post ]

The image below shows hourly methane average recorded at the Barrow Atmospheric Baseline Observatory (BRW), a NOAA facility located near Utqiaġvik (formerly Barrow), Alaska, at 71.32 degrees North.


The image below shows a (+3 h) forecast for methane concentration at 850 hPa valid for August 26, 2025 (run August 25, 2025).

The image below shows that the NOAA 20 satellite recorded methane levels as high as 2507 parts per billion (ppb) at 399.1 mb on August 26, 2025 AM. 


Climate Emergency Declaration

The temperature rise is accelerating and the rise could accelerate even more due to decreases in buffers (as described in earlier posts such as this one), due to strengthening feedbacks, especially during an El Niño, and due to further reduction of the aerosol masking effect, which are all developments that could rapidly speed up existing feedbacks and trigger new feedbacks.

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.net

• Climate Reanalyzer

• NOAA - sea surface temperatures 
Also discussed on facebook at: 

• NOAA - Climate Prediction Center - ENSO: Recent Evolution, Current Status and Predictions

• ECMWF - El Niño forecast

• Extreme Heat Risk

• University of Bremen

• Danish Meteorological Institute - Arctic sea ice thickness and volume

• NOAA - CarbonTracker-CH4

• The Methane Monster





Monday, July 10, 2023

Arctic sea ice July 2023

World temperatures during each of the past 16 days have been higher than they have been for millions of years. Moreover, the temperature is now rising faster than during any period before, and could rise 18.44°C (versus pre-industrial) by the year 2026.


In each of the past 16 days, the temperature has been higher than the peak temperature reached in previous years in the record going back to 1979, i.e. 16.92°C (62.46°F) reached on July 24, 2022 (orange), as well as on August 13+14, 2016.
July   3, 2023: 17.01°C or 62.62°F
July   4, 2023: 17.18°C or 62.92°F
July   5, 2023: 17.18°C or 62.92°F
July   6, 2023: 17.23°C or 63.01°F
July   7, 2023: 17.20°C or 62.96°F
July   8, 2023: 17.17°C or 62.91°F
July   9, 2023: 17.11°C or 62.80°F
July 10, 2023: 17.12°C or 62.82°F
July 11, 2023: 17.08°C or 62.74°F
July 12, 2023: 17.04°C or 62.67°F
July 13, 2023: 16.98°C or 62.56°F
July 14, 2023: 16.94°C or 62.49°F
July 15, 2023: 16.99°C or 62.58°F
July 16, 2023: 17.03°C or 62.65°F
July 17, 2023: 17.11°C or 62.80°F
July 18, 2023: 17.17°C or 62.91°F
The comparison with the year 2016 is important, since 2016 was a strong El Niño year and the peak temperature in that year was reached in August. Therefore, if indicative, temperatures in 2023 may reach even higher peaks later this month and in August, which seems confirmed by predictions of the currently unfolding El Niño, such as the above image from Copernicus, showing El Niño gaining in strength.

Arctic Ocean heating up

The Arctic reached high temperatures on July 9, 2023, as illustrated by the combination image below, created with nullschool.net images.

[ click on images to enlarge ]
1. Firstly, the water of the Arctic Ocean heats up as it receives direct heat from sunlight. The globe on the right on the above combination image shows that on July 9, 2023, a temperature of 33°C or 91.3°F was recorded in Canada over land near the Arctic Ocean and near the Mackenzie River (green circle), with the heatwave on land extending over the Arctic Ocean. As the globe at the center shows, sea surface temperature anomalies as high as 13.2°C or 23.7°F were recorded that day nearby, in the area marked by the green circle. 

2. Hot water from rivers ending in the Arctic Ocean is another way the water is heating up, as also illustrated by the above image. 

The above globe on the left shows that, on July 9, 2023, sea surface temperatures as high as 13.5°C or 56.4°F were recorded at a location nearby location where the Mackenzie River flows into the Arctic Ocean (at the green circle), while on July 23, 2023, the sea surface was 13.8°C or 24.8°F hotter than in 1981-2011, at a nearby location where the Mackenzie River is flowing into the Arctic Ocean.  

As illustrated by the image on the right, the sea surface was 18.4°C or 33°F hotter than in 1981-2011 where the Ob River meets the Kara Sea (at the green circle) on July 24, 2023.  

The image on the right shows sea surface temperatures in the Bering Strait as high as 18.8°C or 65.4°F on July 27, 2023. The water heats up strongly where hot water from rivers and run-off from rainwater enters the Bering Strait. 

3. Yet another way heat is entering the Arctic Ocean is from oceans, i.e. from the North Atlantic Ocean and the Pacific Ocean, and this is melting the sea ice from below. 

The image below, created with Climate Reanalyzer images, shows that the North Atlantic sea surface temperature was 24.8°C on July 21, 2023 (black), no less than 1.2°C higher than the 23.6°C recorded on July 21, 2022 (orange).


As the above image also shows, a record high temperature was reached on the North Atlantic of 24.9°C on September 4, 2022. 

The comparison with the peak in 2022 is important, as it was reached at a time when La Niña was suppressing the temperature, whereas now El Niño is strongly pushing up the temperature. Therefore, if the 1.2°C difference is indicative, temperatures above 26°C can be expected for the North Atlantic in September this year.

The image on the right shows sea surface temperatures as high as 33.6°C or 92.4°F off the Florida coast (green circle) on July 13, 2023.

A buoy in Manatee Bay in the Upper Keys south of Florida recorded a water temperature of 38.89°C or 101.1°F on July 24, 2023.

The image below shows sea surface temperatures as high as 33°C or 91.4°F on July 27, 2023.


The video below gives a sequential view of the situation:


The Gulf Stream is pushing ocean heat toward the Arctic Ocean, as illustrated by the image below.


It takes some time for peak ocean heat to reach the Arctic Ocean. Arctic sea ice typically reaches an annual minimum extent about mid-September.

As the above image also shows, a sea surface temperature east of Svalbard of 10.6°C or 51°F was recorded on July 15, 2023 (at the green circle).

Arctic sea ice under threat

As described in earlier posts such as this one, this rapid temperature rise threatens to cause Arctic sea ice to disappear.

The three images on the right, adapted from University of Bremen, shows that Arctic sea ice thickness is very vulnerable. 

The top image shows that most Arctic sea ice was less than 20 cm thick on July 16, 2023.

The second image on the right shows Arctic sea ice concentration on July 9, 2023.

The image underneath shows sea ice age for the week of June 25 to July 1, 2023, from NSIDC.

More generally, the rapid temperature rise threatens to cause numerous feedbacks to accelerate and further developments to occur such as crossing of tipping points, with the danger that the temperature will keep rising.

Ominously, some very high methane levels were recorded recently at Barrow, Alaska, as illustrated by the NOAA image below.

Conclusion

The outlook is dire and is getting more dire every day.

This calls for a Climate Emergency Declaration and implementation of comprehensive and effective action, as described in the Climate Plan with an update at Transforming Society


Links


• Nullschool
https://earth.nullschool.net

• Climate Reanalyzer - sea surface temperature

• Potential world record: South Florida ocean temperature surges beyond 100 degrees 

• Copernicus

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

• The Threat
https://arctic-news.blogspot.com/p/threat.html

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

• NSIDC - Mid-summer bliss - sea ice age
https://nsidc.org/arcticseaicenews/2023/07/mid-summer-bliss

• NOAA - Global Monitoring Laboratory - Barrow, Alaska





Saturday, July 23, 2022

Arctic sea ice July 2022

Blue Ocean Event

[ from Blue Ocean Event ]
A Blue Ocean Event occurs when virtually all sea ice disappears and the surface color changes from white (sea ice) to blue (ocean). According to many, a Blue Ocean Event starts once Arctic sea ice extent falls below 1 million km².

The image on the right shows a trend pointing at zero Arctic sea ice volume by September 2027.

Note that the volume data in the image are averages for the month September ⁠— the minimum for each year is even lower. Furthermore, since zero volume implies zero extent, this indicates that a Blue Ocean Event (extent below 1 million km²) could happen well before 2027.

Sea ice extent

The image below, adapted from NSIDC, shows the extent of Arctic sea ice on July 26, 2022. 
[ click on images to enlarge ]

The extent of Arctic sea ice was among the lowest on record for the time of year on July 26, 2022. Furthermore, Antarctic sea ice extent is currently at a record low for the time of year, as illustrated by the image below, adapted from Vishop and showing the situation up to July 27, 2022. 


As a result, global extent of sea ice is close to record low for the time of year, as illustrated by the image below, adapted from Vishop and showing the situation up to July 27, 2022. 


Both Vishop and NSIDC use 15% concentration as the threshold for including an area in calculations of sea ice extent. This makes it important to look at the concentration of the sea ice. 

Sea ice concentration

The image below, adapted from University of Bremen, shows Arctic sea ice concentration on July 22, 2022, with concentration in many areas close to the North Pole down to 0%. 


The image below, adapted from NSIDC, shows Arctic sea ice concentration on July 26, 2022, with very low concentration of sea ice visible close to the North Pole. 


Sea ice thickness

The Naval Research Laboratory one-month animation below shows Arctic sea ice thickness up to July 25, 2022, with 8 days of forecasts added. 


The combination image below shows the fall in Arctic sea ice thickness from June 8 through August 6, 2022.

[ click on images to enlarge ]
The above combination image shows that most sea ice on June 8 (left) was forecast to be over 2 meters thick, that most sea ice on July 8 (center) was forecast to be over 1 meter thick, and that most sea was forecast to be under 1 meter thick on August 6, 2022 (right).

While the fall in extent over this period wasn't as dramatic, due to the suppression of air temperatures by the current La Niña, note that the green and yellow colors where the sea ice on June 8 was more than 2.5 meters thick, north of Greenland and north of the Canadian Arctic Archipelago, have virtually disappeared in the August 6 forecast.

The above maps show a dramatic fall in sea ice thickness over a large area. This fall in thickness is mostly due to warm water from the Atlantic Ocean that is melting the sea ice hanging underneath the surface. This is where the sea ice constitutes the latent heat buffer, consuming incoming heat in the process of melting.

The above Naval Research Laboratory maps may be conservative. The NASA Worldview and University of Bremen images below indicate that Arctic sea ice may be even thinner than that, especially north of the North Pole. 

The NASA Worldview combination image below shows the sea ice north of the North Pole on July 22, 2022 (left), and on July 23, 2022 (right), indicating that at many places there is no sea ice left at all. Note that the view in many places is obscured due to clouds. 


The University of Bremen combination image below shows the difference in sea ice thickness between June 1, 2022, June 30, 2022, and July 22, 2022. The images at the center and on the right show large areas where sea ice is less than 20 cm thick, indicating that the latent heat buffer had already disappeared in June 2022,  as also discussed further below. 

[ click on images to enlarge ]
The NASA Worldview combination image below shows the sea ice north of Greenland on July 19, 2022 (top), and on July 22, 2022 (bottom), indicating that even at places where the sea ice once was the thickest, it can melt away rapidly. The mechanism behind this is that, as thick ice breaks off and fragments, it additionally gets heated up from the sides, and this further accelerates the melting as the sea ice breaks up further, into ever smaller pieces.


The image below was created with a screenshot of a July 26, 2022, NASA Worldview satellite image, with the Earth at Night layer activated and brightness and contrast enhanced, which enables a closer look to be taken through the clouds. The image shows very little sea ice near the North Pole. 


The image below, a screenshot of a July 26, 2022, NASA Worldview satellite image, further shows that there is little sea ice close to the North Pole. 


Conditions behind the danger

One reason why sea ice has fallen so much in thickness so close to the North Pole is that around the time of the June Solstice (June 22, 2022) the North Pole receives more insolation than anywhere else on Earth.

Around this time of year, the sunlight has less distance to travel through the thinner atmosphere over the Arctic, so less sunlight gets absorbed or scattered before reaching the surface. In addition, the high angle of the Sun produces long days and sunlight is concentrated over a smaller area. Above the Arctic Circle, the Sun does not set at this time of year, so solar radiation continues all day and night.


How much sunlight does reach the surface further depends on weather conditions such as clouds and how much heat gets pushed by the wind toward the North Pole. As temperatures have risen over the years, the Jet Stream has become more deformed, increasing the chance that heatwaves over land extend over the Arctic Ocean. Deformation of the Jet Stream can also lead to increasingly strong winds speeding up ocean currents that can abruptly push huge amounts of ocean heat into the Arctic ocean, as further discussed below. For more background, also see the feedbacks page. 

Ocean heat

On July 19, 2022, the sea surface was as warm as 1.8°C or 35.2°F north of Greenland, as the nullschool.net image below shows. 


The above image also shows how cold water (blue) flows down to the east of Greenland, while warm water (green) flows off the west coast of Norway toward to Arctic Ocean, diving under the sea ice north of Svalbard and reaching areas north of Greenland where sea surface temperatures rise above freezing point. 

Of the extra heat from Earth's energy imbalance, about 93% ends up in the ocean as increasing ocean heat content (see image below), 3% goes into melting ice, 4% goes into raising temperatures of land and melting permafrost, and less than 1% remains in the atmosphere, as discussed in an earlier post.

[ from earlier post ]

Sea ice has disappeared in the Bering Strait, in part due to warm water from rivers in Alaska, as illustrated by the NOAA image below, which shows sea surface temperatures as high as 18.6°C or 65.48°F.


On July 19, 2022, the sea surface temperature anomaly from 1981-2011 in the Arctic Ocean was as high as 14.0°C or 25.2°F (at green circle), as illustrated by the screenshot below of a nullschool.net image (with text added). In 1981-2011, the sea surface temperature at this spot (at the green circle in the Kara Sea) at this time of year was around freezing point.


The above image also shows a distorted Jet Stream (at 250 hPa) moving over the Arctic ocean, instead of circumventing the Arctic and thus keeping heat out of the Arctic and keeping cold inside the Arctic, as it used to be.  


The above NOAA image illustrates how the Gulf Stream is pushing warm water toward the Arctic, with sea surface temperatures in the North Atlantic reaching as high as 32.6°C or 90.68°F on July 23, 2022.

Latent heat

Latent heat is heat that is (less and less) going into melting the sea ice. The reason this heat is called latent (hidden) heat, is that it doesn't raise the temperature of the water, but instead gets consumed in the process of melting the ice. Latent heat is energy associated with a phase change, such as the energy consumed when solid ice turns into water (i.e. melting). During a phase change, the temperature remains constant. Sea ice acts as a buffer that absorbs heat, while keeping the temperature at zero degrees Celsius. As long as there is sea ice in the water, this sea ice will keep absorbing heat, so the temperature doesn't rise at the sea surface. 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.


Once most of the sea ice that was hanging underneath the surface is gone, further heat will still keep moving underneath the sea ice from the Atlantic Ocean and - to a lesser extent - from the Pacific Ocean into the Arctic Ocean. Without the latent heat buffer, this heat must go elsewhere, i.e. it will typically raise the temperature of the water. The atmosphere will also warm up faster. More evaporation will occur once the sea ice is gone, further warming up the atmosphere.

A 2019 analysis concludes that the latent heat tipping point gets crossed when the sea surface temperature anomaly on the Northern Hemisphere gets higher than 1°C above 20th century's temperature and when there is little or no thick sea ice left. As the image below indicates, the temperature anomaly of 1°C above the 20th century average looks set to be crossed in the course of the year 2021.
As the Latent Heat Tipping Point gets crossed, there may still be a thin layer of ice at the surface, at least as long as air temperatures are low enough to keep it frozen and as long as strong winds haven't pushed the sea ice out of the Arctic Ocean. This thin layer of ice will still consume some ocean heat below the surface, but at the same time it acts as a seal, preventing heat from the Arctic Ocean to enter the atmosphere. Even if a lot of sea ice remains, the situation is dangerous, if not even more dangerous. The continuing La Niña could cause a lot of thin sea ice to remain at the surface of the Arctic Ocean this year. The more sea ice remains, the less ocean heat can be transferred from the Arctic Ocean to the atmosphere over the Arctic Ocean, which means that more heat remains in the Arctic Ocean.

One huge danger is that, as the buffer disappears that until now has consumed huge amounts of ocean heat, more heat will reach methane hydrates at the seafloor of the Arctic Ocean, causing them to get destabilized and resulting in releases of methane from these hydrates and from free gas underneath that was previously sealed by the hydrates.

As the latent heat buffer of the sea ice underneath the surface disappears, more of this heat could then reach sediments at the seafloor of the Arctic Ocean, threatening eruptions to occur of seafloor methane (from hydrates and from free gas underneath the hydrates). The methane could similarly push up temperatures dramatically over the Arctic, and globally over the next few years.

[ feedback #14: Latent Heat ]

The above 2014 image, from the feedbacks page, shows three of the numerous feedbacks that are accelerating warming in the Arctic. Feedback #1 is the albedo feedback. Feedback #14 refers to the loss of the Latent Heat Buffer and warming of the Arctic Ocean. Feedback #2 refers to methane releases.

Heatwaves look set to continue on the Northern Hemisphere, extending heat over the Arctic Ocean and thus affecting Arctic sea ice from above, while warm water from rivers will cause more melting at the surface, and while rising ocean heat will continue to cause more melting of the ice underneath the surface. If this continues, we can expect a new record low for sea ice in September 2022 and the joint loss of the latent heat buffer and the loss of albedo could push up temperatures dramatically over the Arctic, while the additional methane could similarly push up temperatures dramatically over the Arctic, and globally over the next few years.

[ The Buffer has gone, feedback #14 on the Feedbacks page ]
As discussed at the albedo page and the feedbacks page, albedo change, loss of the latent heat buffer and changes to the Jet Stream are important feedbacks. 


The above image, adapted from an ECMWF.int forecast for July 29, 2022, 12 UTC, run at that time, shows virtually no snow and ice cover over land except Greenland. The image also shows the difference such cover or the lack thereof makes in albedo. 

[ click on images to enlarge ]
The above image, adapted from NOAA Coral Bleaching Heat Stress Monitoring, shows expected coral bleaching heat stress for August to November 2022. The image on the right shows that coral bleaching alert level 2 was reached in the Barents Sea (green circle) on July 29, 2022, while a distorted Jet Stream is pushing warm, salty water from the Atlantic Ocean into the Arctic Ocean. 

2022 study of the Blob, a warm water area in the North Pacific that began in late 2013, concludes that the unusually warm waters were transported northward from further south. The researchers found that abnormally warm temperatures extended 1,000 meters (3,280 feet) below the surface.


The above image shows the Blob on July 24, 2022, with sea surface temperature anomalies as high as 10.5°C or 18.8°F on July 24, 2022. The North Pacific Current is visible, extending eastward from the coast of Japan.

Arctic-news has long (e.g. in this 2017 post) warned that changes to the Jet Stream can strengthen storms that can in turn cause a large amount of warm, salty water to abruptly move north and enter the Arctic Ocean from the Atlantic Ocean and trigger destabilization of methane hydrates at the seafloor of the Arctic Ocean, resulting in eruption of huge amounts of methane that could drive humans into extinction in a matter of years. 


Conclusion

In conclusion, temperatures could rise strongly in the Arctic soon, due to sea ice loss in combination with feedbacks and an upcoming El Niño coinciding with a peak in sunspots, with the potential to drive humans extinct as early as in 2025, while temperatures would continue to skyrocket in 2026, making it in many respects rather futile to speculate about what will happen beyond 2026. At the same time, the right thing to do now is to help avoid the worst things from happening, through comprehensive and effective action as described in the Climate Plan.


Links

• Blue Ocean Event
https://arctic-news.blogspot.com/p/blue-ocean-event.html

• National Snow and Ice Data Center (NSIDC)
https://nsidc.org

• Visualization Service of Horizontal scale Observations at Polar region (Vishop) 
https://ads.nipr.ac.jp/vishop/#/extent

• Naval Research Laboratory
https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/arctic.html

• University of Bremen
https://seaice.uni-bremen.de/databrowser

• NASA Worldview satellite
https://worldview.earthdata.nasa.gov

• NOAA - sea surface temperature

• Human Extinction by 2025?