Thursday, September 8, 2022

Blue Ocean Event 2022?

The image on the right shows a NASA Worldview satellite image of a blue Beaufort Sea (with Barrow, Alaska, at the top left, on September 7, 2022). 

The image shows that there is a lot of open water between the coast of Alaska and the sea ice.

Such a satellite image provides a visual way to determine how much sea ice is present. It can be hard to determine where there is open water and where the sea ice starts; the sea ice is often covered by clouds; furthermore, even when there are no clouds, the question remains what is to be regarded as sea ice and what is to be regarded as water. 

Another way to measure how much sea ice is there is to look at sea ice concentration. Sea ice concentration in the Central Arctic region has been very low for some time. 

The image on the right, from an earlier post, shows that on August 12, 2022, sea ice concentration in a large area close to the North Pole was as low as 0%. 

In the two images below, Nico Sun calculates the impact of albedo loss based on NSIDC sea ice concentration data. The images illustrate why sea ice loss in the Central Arctic region is so important.

The image below shows that further albedo loss in the Barents Sea, which is virtually icefree at the moment, doesn't make much difference now. 



The image below shows that, by contrast, more albedo loss in the Central Arctic region makes much more difference, even in September. 


Arctic sea ice has become extremely thin, so the latent heat buffer loss is also very strong. This loss of the latent heat buffer can continue to result in higher temperatures of the water for a long time, even long after insolation has passed its annual peak on the Northern Hemisphere, thus causing the combined accumulative impact to continue to be high.

Another way to measure how much sea ice is present is to look at the extent of the sea ice. According to many, a Blue Ocean Event starts once the Arctic sea ice falls below 1 million km² in extent.

Arctic sea ice extent was 4.912 million km² on September 6, 2022, which is larger than the extent in many previous years around this time of year (see NSIDC image below). However, the sea ice has become very thin, resulting in many areas where only small pieces of ice are present. 


NSIDC regard a cell to have sea ice if it has at least 15% sea ice, but when regarding a cell to have sea ice if it has at least 50% ice and if that's the case for ⅕ of the cells where there is (some) ice, then we're already in a Blue Ocean Event right now.

So let's have another look at how much of the above 4.912 million km² can be regarded as sea ice, by using the NSIDC map with sea ice concentration as a guide. 

The roughly-sketched outline drawn over the NASA map below indicates that there may only have been some 991 thousand km² of concentrated sea ice left on September 6, 2022 (inset shows NSIDC sea ice concentration for the day). 


As said, it's a rough sketch, so some cells with a higher concentration of sea ice may have been left out. Having said that, we're currently in the depth of a persistent La Niña and the associated lower air temperatures contribute to a relatively larger sea ice extent than would otherwise be the case. 

In conclusion, depending on what is counted as sea ice, we could already be experiencing a Blue Ocean Event right now. 

Further events and developments

A Blue Ocean Event constitutes the crossing of a huge tipping point and, as a strong El Niño looks set to emerge, this could trigger the unfolding of further events and developments leading to extinction of most species (including humans), as: 
  1. a strong El Niño triggers: 
  2. further decline of the Arctic sea ice, with loss of the latent heat buffer, combined with
  3. associated loss of sea ice albedo and
  4. destabilization of seafloor methane hydrates, causing eruption of vast amounts of methane that further speed up Arctic warming and cause
  5. rapid thawing of terrestrial permafrost, resulting in even more emissions,
  6. while the Jet Stream gets even more deformed, resulting in more extreme weather events
  7. causing forest fires, at first in Siberia and Canada and
  8. eventually also in the peat fields and tropical rain forests of the Amazon, in Africa and South-east Asia, resulting in
  9. decline of snow and ice on mountains, at first causing huge flooding, followed by 
  10. drought, heatwaves and urban collapse,
  11. collapse of the Greenland and West-Antarctic ice sheets,
  12. falling away of aerosol masking as civilization grinds to a halt, 
  13. further heating due to gases and particulates from wood and waste burning and biomass decomposition, and 
  14. further heating due to additional gases (including water vapor), cirrus clouds, albedo changes and heat rising up from oceans. 


Importantly, depicted above is only one scenario out of many. Things may eventuate in different order and occur simultaneously, i.e. instead of one domino tipping over the next one sequentially, many events may occur simultaneously and reinforce each other. Further events and developments could be added to the list, such as ocean stratification and stronger storms that can push large amounts of warm salty water into the Arctic Ocean.


Here is another example of such a scenario. Recent studies indicate that human-caused climate change will soon increase El Niño frequency and intensity. Accordingly, the upcoming El Niño may well be strong. As illustrated with above image, we're currently in the depth of a persistent La Niña, which suppresses the temperature rise, whereas the opposite occurs during El Niño, which amplifies the temperature rise, and this especially affects the Arctic, which is already heating up much faster than the rest of the world. Also, the upcoming El Niño may very well coincide with a peak in sunspots in 2025, further pushing up temperatures.

The image below shows that the rise in sea surface temperatures on the Northern Hemisphere has been suppressed during the ongoing La Niña, but as we move into the next El Niño, the seafloor methane tipping point could be crossed even earlier than the current trend indicates, say by 2025. 


One reason for this is that the narrowing temperature difference between the Arctic and the Tropics will further deform the Jet Stream and in turn cause more extreme weather, leading to more loss of sea ice and thus of its capacity to reflect sunlight and act as a buffer against incoming ocean heat.

A huge amount of heat has built up in the North Atlantic off the coast of North America, as illustrated by the image on the right.

Furthermore, the temperature of the water may well be substantially higher some 50 meter below the sea surface than at the sea surface. 

As discussed in an earlier post, rising temperatures result in stronger winds along the path of the Gulf Stream that can make huge amounts of warm, salty water travel from the Atlantic Ocean toward the Arctic and reach shallow parts of the Arctic Ocean such as the East Siberian Arctic Shelf (ESAS), where most of the sea is less than 50 m deep. The danger is illustrated by the Argo float compilation below.



Very high methane levels

The image below, from an earlier post, shows annual global mean methane with a trend added that points at a methane rise that could in 2028 represent a forcing of 780 ppm CO₂e (with a 1-year GWP of 200). 

In other words, the clouds tipping point at 1200 ppm CO₂e could be crossed in 2028 due to the forcing of methane and CO₂ alone, assuming that CO₂ concentration in 2028 will exceed 420 ppm. Moreover, this could happen even earlier, since there are further forcers, while further events and developments could additionally push up the temperature further, as discussed above. Furthermore, the NOAA data used in the above image are for marine surface measurements. More methane tends to accumulate at higher altitudes, as illustrated by the compilation image below. 


NOAA's globally averaged marine surface mean for April 2022 was 1909.9 ppb. The above image shows that, on September 4, 2022 am, the MetOp satellite recorded a mean methane concentration of 1904 ppb at 586 mb, which is close to sea level. At 293 mb, however, the MetOp satellite recorded a mean of 1977 ppb, while at 218 mb it recorded a peak of 2805 ppb. 

Such high methane levels could be caused by destabilization of methane hydrates at the seafloor of the Arctic Ocean, with large amounts of methane erupting (increasing 160 x in volume) and rising up at accelerating speed through the water column (since methane is lighter than water), concentrated in the form of plumes, which makes that less methane gets broken down in the water by microbes and in the air by hydroxyl, of which there is very little in the Arctic in the first place. Such a methane eruption entering the atmosphere in the form of a plume can be hard to detect as long as it still doesn't cover enough of the 12 km in diameter footprint to give a pixel the color associated with high methane levels. 


The above Copernicus image shows a forecast  for September 9, 2022 18 UTC, of methane at 500 hPa. 

In the video below, from this page, Guy McPherson addresses the question: Has the “Methane Bomb” Been Triggered?


Conclusion

The situation is dire and the right thing to do now is to help avoid or delay the worst from happening, through action as described in the Climate Plan. 


Links

• NSIDC - Frequently asked questions

• NASA Worldview

• NSIDC - sea ice concentration

• Nico Sun - CryosphereComputing

• NSIDC - sea ice extent

• More Frequent El Niño Events Predicted by 2040
Cutting-edge models predict that El Niño frequency will increase within 2 decades because of climate change, regardless of emissions mitigation efforts.

• Emergence of climate change in the tropical Pacific - by Yun Ying et al. 
https://www.nature.com/articles/s41558-022-01301-z

• Climate Reanalyzer

• Argo Float

• Monitoring of atmospheric composition using the thermal infrared IASI/MetOp sounder - by C. Clerbaux et al. 

• NOAA - MetOp satellite methane data 

• Copernicus methane forecasts

• Clouds feedback and tipping point

• NOAA - global methane

• NOAA - Sea surface temperature anomalies on the Northern Hemisphere 

• NOAA - Monthly Temperature Anomalies Versus El Niño

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

• WMO predicts first “triple-dip” La Niña of the century


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Monday, August 22, 2022

Dangerously large Arctic sea ice extent

Arctic sea ice extent was 5.88 million km² on August 21, 2022, larger in extent than in any of the years from 2010 through 2021 at this time of year, as illustrated by the NSIDC image below. 


At first glance, one might think that this relatively large extent was a sign of healthy sea ice. After all, the larger the sea ice, the more sunlight gets reflected back into space. At the same time, however, the situation is very dangerous, as there is a growing risk that large eruptions of methane will occur from the seafloor of the Arctic Ocean.

Why is the situation so dangerous? There are many contributors to the danger, three of them are:

1. Ice acts as a seal

Ice acts as a seal, insulating the soil from warmer air and holding the soil together, like a glue. A 2022 study by Elizabeth Webb et al. concludes that rainwater carries heat into the soil and accelerates permafrost thaw, and the glue that holds the soil together disappears. This can open up underground channels that drain the surface. 

Rainwater can also travel along cracks deeper into sediments, where the heat can destabilize methane hydrates, resulting in the release of large amounts of methane into the atmosphere from hydrates and from gas underneath hydrates. As temperatures rise in the Arctic, more rain will fall over the Arctic, increasing this danger.


Where rain falls onto the sea ice, the rainwater also adds heat to the sea ice, speeding up its demise, and stronger winds can further accelerate this. The compound impact is that such feedbacks accelerate the pace at which the Arctic is warming, but as long as air temperatures are low enough, there will continue to be sea ice that acts as a seal, impeding transfer of ocean heat from the Arctic Ocean to the atmosphere. 

Temperatures in the Arctic are rising faster than in the rest of the world. As temperatures rise in the Arctic, increased precipitation, meltwater and runoff from land, and flow of freshwater from rivers all decrease salinity of the water in the Arctic Ocean. Lower salinity makes it harder for sea ice to melt. 

As temperatures in the Arctic are rising faster than in the rest of the world, the Jet stream is getting deformed. Deformation of the Jet Stream causes more wind to go over the Arctic Ocean, which can cool down the sea surface, resulting in more extensive sea ice. 

Furthermore, we're currently in the depth of a persistent La Niña (NOAA image on the right), and the associated lower air temperatures further contribute to a relatively larger extent of the sea ice. 

More extensive sea ice in turn makes it harder for ocean heat to be transferred to the atmosphere, thus instead raising the temperature of the water of the Arctic Ocean.


The larger the sea ice is in extent, the less ocean heat can be transferred from the Arctic Ocean to the atmosphere, which means that more heat will remain in the Arctic Ocean.

2. Lid on North Atlantic

 Ocean stratification is increasing globally, as ocean warming is stronger for upper layers versus the deep ocean. Stratification increased from 1960 to 2018 by 5.3% for the upper 2000m and by as much as 18% for the upper 150m, while salinity changes also play an important role locally, a 2020 study finds.

[ SSTA (left) and SST (right), August 23, 2022 - click on image to enlarge ]

Deformation of the Jet Stream can at times strongly increase evaporation over the North Atlantic with more precipitation further down the path of the Atlantic meridional overturning circulation (AMOC).

Deformation of the Jet Stream can also increase runoff from land (including from melting glaciers).

In both these cases, this can contribute to the formation and growth of a relatively cold, freshwater lid at the surface of the North Atlantic.


This lid on the North Atlantic reduces transfer of ocean heat to the atmosphere and enables large amounts of salty, warm water to enter the Arctic Ocean, diving under the sea ice. 

This lid also increases the risk of a sudden, large influx of hot, salty water. Slowdown of AMOC causes ocean heat to accumulate, while more warm water travels underneath this lid (instead of at the sea surface) toward the Arctic Ocean. As the Jet Stream gets more deformed, strong winds along the path of AMOC can at times speed up the flow of water that travels underneath this cold freshwater lid over the North Atlantic, suddenly pushing large amounts of salty, warm water into the Arctic Ocean. 

3. Latent heat buffer loss

The navy.mil combination image below has three panels. The left panel shows the sea ice on August 30, 2012, the center panel shows the sea ice on August 30, 2015, and the right panel shows a forecast for the sea ice for August 30, 2022, run on August 22, 2022.


The image illustrates that Arctic sea ice is currently larger in extent than it was in 2012 and 2015 at this time of year, while there has been a dramatic reduction in thickness of the sea ice over time.

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.


This ice has meanwhile all but disappeared, so without this latent heat buffer further incoming heat must go elsewhere, i.e. the heat will further raise the temperature of the water of the Arctic Ocean.

Compound impact

The danger is that, as more salty, warm water keeps arriving in the Arctic Ocean while the latent heat buffer has largely disappeared and while sea ice extent is relatively large, this will raise the temperatures and salinity levels at the bottom of the Arctic Ocean enough to destabilize hydrates in sediment at the seafloor of the Arctic Ocean, resulting in methane eruptions both from these hydrates and from free gas underneath these hydrates.

[ The Buffer has gone, feedback #14 on the Feedbacks page ]
Very high methane levels

The Copernicus image below shows a forecast of high levels of methane over the Arctic on August 28, 2022 18:00 UTC at 500 hPa. 


Methane levels are already at record high and growth is accelerating, even without an extra burst of seafloor methane. The NOAA record shows that methane grew by 18.31 ppb in 2021, the highest annual growth on record. 

The most recent monthly NOAA data are for the globally averaged marine surface mean for April 2022, which was 1909.9 ppb. This is 18.7 ppb higher than April 2021, as illustrated by the image on the right, from an earlier post.

NOAA's data are for marine surface measurements. More methane tends to accumulate at higher altitudes, as illustrated by the two data images on the right.

The top data image on the right shows methane recorded by the MetOp satellite on August 22, 2022 am. The image shows means of 1972 ppb at five pressure levels (of 280 mb and less), with a peak level of 2543 ppb, the highest that day, occurring at 218 mb.

The second data image on the right shows methane means recorded by the MetOp satellite on August 25, 2022 pm of 1975 ppb at four pressure levels (at 254 mb, 266 mb, 280 mb and 283 mb).

The image underneath on the right shows a methane peak of 2622 ppb (marked by the red oval), recorded by the N20 satellite on August 20, 2022 am at 399.1 mb. High methane levels are visible north of Siberia, indicating that much of the methane may originate in the Arctic.

Another N20 satellite image is added underneath showing high methane concentrations over the Arctic, also on August 20, 2022 am, but at 695.1 mb, which is much closer to sea level. This confirms that much of the methane may have originated in the Arctic.

An image is added underneath from another satellite, the MetOp satellite, also showing high methane concentrations over the Arctic, also on August 20, 2022 am, this time at 586 mb, further confirming that much of the methane may have originated in the Arctic.

A large abrupt methane release could double the methane in the atmosphere. Methane releases from the seafloor of the Arctic Ocean are very dangerous because there is very little hydroxyl in the atmosphere over the Arctic to break down the methane.
A level twice as high as that 1975 ppb mean is a mean of 3950 ppb, and when using a 1-year GWP of 200, this translates into 790 ppm CO₂e, i.e. only 410 ppm away from the 1200 ppm clouds tipping point.

The average monthly CO₂ at Mauna Loa, Hawaii, was 420.99 ppm both in May and in June 2022. As illustrated by the image on the right, average daily CO₂ hasn't been below 416 ppm in July and August 2022, while some hourly measurements were around 425 ppm CO₂.
On August 25, 2022 16:30 UTC, CO₂ at the North Pole was 422 ppm, as illustrated by the nullschool.net image on the right. 

In other words, a large eruption of methane from the seafloor of the Arctic Ocean could abruptly cause the joint CO₂e of just two greenhouse gases, i.e. methane and CO₂, to cross the 1200 ppm clouds tipping point globally and trigger a further 8°C global temperature rise, due to the clouds feedback alone. When adding further forcers, a huge temperature rise could be triggered even with far less methane erupting from the seafloor.

Conclusion

In conclusion, there is a growing danger that methane will erupt from the seafloor of the Arctic Ocean and cause a dramatic rise in temperature.

Even without such eruption of methane from the seafloor of the Arctic Ocean, temperatures look set to rise strongly soon, as we move into an El Niño and face a peak in sunspots. 

Either way, the resulting temperature rise could drive humans extinct as early as in 2025 with temperatures continuing to skyrocket in 2026. 

This makes 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.


Arctic sea ice (earlier posts in 2022)

• Arctic sea ice June 2022 - why the situation is so dangerous
https://arctic-news.blogspot.com/2022/06/arctic-sea-ice-june-2022-why-situation-is-so-dangerous.html

• Arctic sea ice July 2022
https://arctic-news.blogspot.com/2022/07/arctic-sea-ice-july-2022.html

• Arctic sea ice August 2022


Further links

• Permafrost thaw drives surface water decline across lake-rich regions of the Arctic - by Elizabeth Webb et al. 
also discussed at: 

• Increasing ocean stratification over the past half-century - by Guancheng Li et al. 
https://www.nature.com/articles/s41558-020-00918-2

• The ocean has become more stratified with global warming - news release

• IPCC AR6 WG1 SPM


• NOAA - Globally averaged marine surface annual mean methane growth rates.

• NOAA - Trends in Atmospheric Carbon Dioxide

• NOAA - MetOp satellite 

• NOAA - N20 satellite

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

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

• NOAA - Monthly Temperature Anomalies Versus El Niño
https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202207/supplemental/page-4

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

• NSIDC - Arctic sea ice concentration
https://nsidc.org/arcticseaicenews

• NSIDC - Chartic, interactive sea ice graph
https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph

• NOAA - Trends in Atmospheric Methane
https://gml.noaa.gov/ccgg/trends_ch4

• nullschool
https://earth.nullschool.net

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

• Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf - by Natalia Shakhova et al. (2019)
https://www.mdpi.com/2076-3263/9/6/251


• Warning of mass extinction of species, including humans, within one decade
https://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html

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

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

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

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

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

• How much time is there left to act?
https://arctic-news.blogspot.com/p/how-much-time-is-there-left-to-act.html

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

• Cataclysmic Alignment
https://arctic-news.blogspot.com/2022/06/cataclysmic-alignment.html

• Human Extinction by 2025?
https://arctic-news.blogspot.com/2022/07/human-extinction-by-2025.html

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

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



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Wednesday, August 10, 2022

Arctic sea ice August 2022

Ocean currents keep pushing heat toward the Arctic Ocean

Arctic sea ice is getting very thin, as temperatures keep rising and ocean currents keep pushing heat toward the Arctic, as illustrated by the NOAA image below that shows sea surface temperatures as high as 33°C or 91.4°F on August 13, 2022. 


The Gulf Stream is an ocean current that extends into the Arctic Ocean, as pictured below and discussed at this page. This ocean current is driven by the Coriolis force and by prevailing wind patterns. 

[ from earlier post ]
This ocean current contributes to the stronger and accelerating warming of the Arctic (compared to the rest of the world), which in turn causes deformation of the Jet Stream that can at times cause strong winds to speed up this ocean current. The image below shows the Jet Stream over the North Atlantic, where the ocean current dives under the sea ice. Sea surface temperature anomalies are much lower over the area where the deformed Jet Stream causes water to evaporate, thus cooling the surface. 


The danger is that a cold freshwater lid grows at the surface of the North Atlantic that enables large amounts of salty, warm water to dive under the sea ice and enter the Arctic Ocean, as discussed earlier here, as well as here and at the feedbacks page. 


Latent heat

Latent heat is ocean heat that is, or rather was previously consumed by melting of the sea ice underneath the sea surface. 

[ The Latent Heat Buffer ]
This ice has meanwhile all but disappeared, so without this latent heat buffer further incoming heat must go elsewhere, i.e. the heat will further raise the temperature of the water and it will also cause more evaporation to take place where the sea ice has disappeared altogether, and this in turn will further heat up the atmosphere over the Arctic. 

The nullschool.net image below shows sea surface temperature anomalies from 1981-2011. At the green circle, anomalies were 16.1°C or 29°F on August 9, 2022. Back in 1981-2011, the temperature at that spot was 0°C. 


Thin layer of sea ice

The image below, adapted from University of Bremen, shows Arctic sea ice concentration on August 12, 2022, with concentration in a large area close to the North Pole as low as 0%.


The image below, from NSIDC, also shows sea ice concentration on August 9, 2022. 


The Naval Research Laboratory image below, a forecast for August 18, 2022, run on August 10, 2022, shows that the sea ice is getting very thin. 

Danger of methane eruptions

The navy.mil combination image below has three panels. The left panel shows the sea ice on August 30, 2012, the center panel shows the sea ice on August 30, 2015, and the right panel shows a forecast for the sea ice for August 21, 2022. 

[ click on images to enlarge ]
[ click on images to enlarge ]
There still is a relatively extensive but very thin layer of sea ice present at the surface. This is also illustrated by the NSIDC image on the right that shows an Arctic sea ice extent of 6.438 million km² on August 11, 2022. This relatively large extent is mainly due to the suppression of air temperatures that comes with the current La Niña (see images further below). 

As long as air temperatures are low enough to keep this surface ice frozen and as long as there are no strong winds pushing the ice out of the Arctic Ocean, this thin layer of ice will act as a seal, preventing transfer of heat from the Arctic Ocean to the atmosphere. 


The larger the remaining sea ice is in extent, the less ocean heat can be transferred from the Arctic Ocean to the atmosphere, which means that more heat will remain in the Arctic Ocean.

[ The Buffer has gone, feedback #14 on the Feedbacks page ]
The danger is that ocean heat keeps arriving in the Arctic Ocean, while the latent heat buffer is gone, causing more of this heat to reach sediments at the seafloor of the Arctic Ocean that threatens to destabilize hydrates in these sediment, resulting in methane eruptions both from these hydrates and from free gas underneath these hydrates.

Record high methane levels 

Methane levels are already at record high and growth is accelerating, even without an extra burst of seafloor methane.

NOAA registered a globally averaged marine surface April 2022 mean of 1909.9 ppb, which is 18.7 ppb higher than April 2021, as illustrated by the image on the right. By comparison, the highest annual growth on the NOAA record is 18.31 ppb for 2021. 

NOAA's data are for marine surface measurements.  More methane tends to accumulate at higher altitudes, as illustrated by the image on the right.

The MetOp satellite recorded a mean global methane level of 1971 ppb at 293 mb on August 11, 2022 am. When using a 1-year GWP of 200, this translates into 394.2 ppm CO₂e.

As the image underneath also shows, the MetOp satellite also recorded a peak methane level of 3009 ppb at 469 mb on August 9, 2022 pm. 

Record high carbon dioxide levels

Carbon dioxide (CO₂) levels have been quite high over the past few months. Monthly CO₂ was 420.99 ppm both in May and in June 2022. Some hourly CO₂ measurements were well above 422 ppm in May 2022. On May 28, 2022, one hourly average at Mauna Loa was recorded of 424 ppm.

When adding this monthly CO₂ concentration of 420.99 ppm to the above 394.2 ppm CO₂e for methane, that gives a total of 815.19 ppm CO₂e. 



Clouds feedback

Copernicus recorded high concentrations of methane over the Arctic Ocean on August 16, 2022 (forecast for 03 UTC run on 00 UTC). 

The image below shows methane at surface level, where the scale goes up to 10,000 ppb. At a 1-year global warming potential of 200, this top end of the scale translates into 2000 ppm CO₂e. 

[ click on images to enlarge ]
This 2000 ppm CO₂e is well above the 1200 ppm CO₂e clouds tipping point that will trigger the disappearance of the lower clouds. The presence of lower clouds and sea ice causes a lot of sunlight to be reflected back into space, so the danger is that at locations where these clouds and sea ice cover have both disappeared, the water of the Arctic Ocean will strongly heat up at this time of year.

What makes the situation in the Arctic very dangerous is that there is very little hydroxyl in the air over the Arctic to break down methane.

Furthermore, the Arctic Ocean in many places is very shallow, especially off the coast of Siberia, as illustrated by the NOAA image on the right. Shallow waters enable hot surface water to be mixed down all the way to the seafloor. 

[ click on images to enlarge ]
This threatens to trigger destabilization of methane hydrates contained in sediments at the seafloor and result in eruption of huge amounts of methane from such hydrates as well as from free gas contained in sediments underneath the hydrates, as illustrated by the image on the right, from this page.

Abrupt eruption of an additional 5 Gt of methane from the seafloor of the Arctic Ocean would double the methane in the atmosphere.  

An amount of 5 Gt of methane is only 10% of the 50 Gt that Natalia Shakhova et al. warned about long ago, while 50 Gt is in turn only a small fraction of all the methane contained in sediments in the Arctic, as illustrated by the image on the right, from Shakhova et al. (2019). 

On its own, a 5 Gt eruption of seafloor methane could raise the global mean methane concentration by as much as 1971 ppb which, at a 1-year GWP of 200, would translate into another 394.2 ppm CO₂e and when added to the above 815.19 ppm CO₂e, adds up to a total of 1209.39 ppm CO₂e.

[ from earlier post, click on images to enlarge ]
So, that would abruptly cause the joint CO₂e of just two greenhouse gases, i.e. methane and CO₂, to cross the 1200 ppm clouds tipping point globally and trigger a further 8°C global temperature rise, due to the clouds feedback alone.

There are further forcers and feedbacks to be taken into account, which means that the clouds tipping point could be crossed globally even with a far smaller abrupt release of seafloor methane. While it would take longer for the clouds tipping points to get crossed that way, the associated temperature rise could be enough to drive humans into extinctions well before the tipping point was even reached. A rise of 3°C above pre-industrial could occur on land and drive humans into extinction by 2025.

La Niña

[ adapted from NOAA - click on images to enlarge ]
As said, sea ice extent is relatively large at the moment, because we are currently in the depths of a persistent La Niña, which is suppressing the temperature rise.

El Niños typically occur every 3 to 5 years, according to NOAA and as also illustrated by the NOAA image below, so the upcoming El Niño can be expected to occur soon.

The NOAA image below indicates that going from the bottom of a La Niña to the peak of an El Niño could make a difference of more than half a degree Celsius (0.5°C or 0.9°F).


Furthermore, the rise in sunspots from May 2020 to July 2025 could make a difference of some 0.15°C (0.27°F). The next El Niño looks set to line up with a high peak in sunspots, in a cataclysmic alignment that could push up the temperature enough to cause even more dramatic sea ice loss in the Arctic, resulting in runaway temperature rise.

Conclusion

In conclusion, there is a growing risk that methane will erupt from the seafloor of the Arctic Ocean and cause a dramatic rise in temperature. 

Even without such eruption of methane from the seafloor of the Arctic Ocean, temperatures look set to rise strongly soon, as we move into an El Niño and face a peak in sunspots. The resulting temperature rise could drive humans extinct as early as in 2025 with temperatures continuing 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.


Arctic sea ice (previous months)

• Arctic sea ice June 2022 - why the situation is so dangerous

• Arctic sea ice July 2022


Further links

• NOAA - Sea Surface Temperature (SST) Contour Charts
• Jet Stream
https://arctic-news.blogspot.com/p/jet-stream.html

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

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

• NOAA - Monthly Temperature Anomalies Versus El Niño
https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202207/supplemental/page-4

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

• NSIDC - Arctic sea ice concentration

• NSIDC - Chartic, interactive sea ice graph

• NOAA - Trends in Atmospheric Methane

• nullschool
https://earth.nullschool.net

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

• Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf - by Natalia Shakhova et al. (2019) 
https://www.mdpi.com/2076-3263/9/6/251

• Warning of mass extinction of species, including humans, within one decade
• Cold freshwater lid on North Atlantic

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

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

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

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

• How much time is there left to act?



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