Wednesday, October 5, 2022

Methane keeps rising

WMO Report on Greenhouse Gases 

In 2020 and 2021, the global network of the World Meteorological Organization (WMO) detected the largest within-year increases (15 and 18 ppb, respectively) of atmospheric methane (CH₄) since systematic measurements began in the early 1980s. 

[ IPCC/WMO data through 2021 ]
The image on the right illustrates methane's rise, showing IPCC and, more recently, WMO data. Methane reached 1908 parts per billion (ppb) in 2021, 262% of the 1750 level, while carbon dioxide (CO₂) reached 415.7 parts per million (ppm) in 2021, 149% of the 1750 level, and nitrous oxide (N₂O) reached 334.5 ppb, 124% of the 1750 level. 

The WMO adds that analyses of measurements of the abundances of atmospheric CH₄ and its stable carbon isotope ratio ¹³C/¹²C (reported as δ¹³C(CH₄)) indicate that the increase in CH₄ since 2007 is associated with biogenic processes.

Methane's rise has been accelerating since 2007, which makes this a scary suggestion, as increasing decomposition of plant material as a result of climate change is a self-reinforcing feedback loop that is hard to stop.

Interestingly, a different explanation is pointed at in the 2019 analysis is shale gas a major driver of recent increase in global atmospheric methane?. 

Another explanation, discussed in an earlier post, is that there was a slowdown from 1984 to 2004 in the rise of methane as a result of rising temperatures increasing the water vapor in the atmosphere, resulting in more hydroxyl decomposing more methane in the atmosphere in the 1990s (compared to the 1980s). Accordingly, while the rise in methane concentration appeared to slow down over those years, methane emissions actually kept growing and continued to do so at accelerating pace, but since an increasingly large part of methane was decomposed by hydroxyl, this continuing rise in methane emissions was overlooked.

This could still mean that plant material is now getting decomposed at higher rates, but an even larger danger is that methane emissions started to increase more strongly from the early 2000s due in part to more methane eruptions from the seafloor of the Arctic Ocean. In other words, while hydroxyl kept increasing, seafloor methane emissions kept increasing even faster, to the extent that methane emissions increasingly started to overwhelm this growth in hydroxyl, resulting in a stronger rise in overall methane abundance in the atmosphere. 

Sadly, there are few measurements available for methane that could erupt from the seafloor of the Arctic Ocean. Moreover, WMO and NOAA data that are used to calculate global means are typically taken at marine surface level, which may be appropriate for carbon dioxide that is present more strongly at sea surface level, but methane is much lighter and will rise quickly and accumulate at higher altitude, as indicated by the satellite images further below. Moreover, the lack of measurements of methane over the Arctic Ocean and at higher altitudes makes it hard to determine from where the methane originated. Much methane could originate from the seafloor of the Arctic Ocean and rise to the Tropopause, while moving from there closer to the Equator, all largely without getting reported.  

What's happening in 2022?

So, what's happening in 2022? Well, it appears that the rise in methane keeps accelerating, as illustrated by the image below showing daily average methane measurements at Mauna Loa, Hawaii, since 2001.

The image below shows methane in situ measurements at Barrow, Alaska, indicating that methane is present in even higher abundance over the Arctic and that levels are rising fast over the Arctic. 


The image below, adapted from Copernicus, shows a forecast for October 27, 2022, 03 UTC at 500 hPa. High levels of methane show up over the Arctic. 


The MetOp-B satellite recorded a mean methane level of 1981 ppb at 293 mb on October 2, 2022 am, while plenty of methane was present over the Arctic Ocean at the three altitudes shown on compilation image below.
The MetOp-B satellite recorded a peak methane level of 2901 ppb at 293 mb on October 20, 2022 am, while plenty of methane was again present over the Arctic Ocean at the three altitudes shown on the compilation image below.

This supports the possibility that large amounts of methane are getting released from the Arctic Ocean, with even more to follow.

While the IPCC keeps hiding the potential for a huge rise in temperature by 2026, as discussed in an earlier post, a recently-published article points out that prudent risk management requires consideration of bad-to-worst-case scenarios. 

How bad could it be? A 2016 analysis warned that there could be a temperature rise of more than 10°C from pre-industral by 2026. An additional danger is that, as methane keeps rising, the clouds tipping point could be crossed even earlier than in 2026. Let's re-evaluate these dangers. 

The above 1981 ppb mean methane level translates into 396.2 ppm CO₂e at a 1-year GWP of 200. Destabilization of sediments at the seafloor of the Arctic Ocean could cause a large abrupt burst of methane to enter the atmosphere over the Arctic Ocean. A doubling of the mean methane level could push up the mean methane level to twice as much, to 792.4 ppm CO₂e, which is only 407.6 ppm CO₂ away from the 1200 ppm CO₂e clouds tipping point that on its own could push up the temperature by some 8°C globally. This gap of 407.6 ppm CO₂ could be more than covered by the current carbon dioxide level. The September 2022 CO₂ level at Mauna Loa was higher than that, i.e. 415.96 ppm. Since the CO₂ level at Mauna Loa in September typically is at its lowest point for the year, this implies that a large abrupt burst of methane could cause the the clouds tipping point to be instantly crossed due to methane and CO₂ alone.

Note that there are additional forcers, such as CFCs, while there are also further events and developments that could additionally speed up the temperature rise, as further discussed below. The scary situation therefore is that the clouds tipping point could be instantly crossed with a burst of methane that is far smaller in size than the methane already in the atmosphere. Such a burst of methane could be released at any time, as discussed in earlier posts such as this one. 

[ from earlier post ]
That's not even the worst-case scenario. In the above calculation, global mean methane levels are used. However, there is a possibility that low-lying clouds could at first break up and vanish abruptly at one specific point, due to a high methane peak, and that this could lead to break-up of neighboring clouds, propagating break-up across the globe and thus pushing up the temperature rise virtually instantly by some 8°C globally.

The MetOp satellite recorded a peak methane level of 3644 ppb and a mean level of 1944 ppb at 367 mb on November 21, 2021, pm, as discussed in an earlier post. This 3644 ppb translates into 728.8 ppm CO₂e, again at a 1-year GWP of 200. This is 471.2 ppm CO₂e away from the clouds tipping point and that 471.2 ppm CO₂e could be covered by the carbon dioxide, nitrous oxide and CFCs currently in the atmosphere.

How high could the temperature rise be by 2026? 

There are a number of scenarios that could cause the clouds tipping point to be crossed soon, e.g. if the rise in methane kept following a trend as depicted in the image below, showing WMO 2015-2021 global annual surface mean methane abundance, with a trend added.

[ click on images to enlarge ]
The trend points at a potential mean global abundance of methane of more than 700 ppm CO₂e by the end of 2026, implying that when including further forcers the clouds tipping point could be crossed in 2026. Furthermore, the trend points at 1200 ppm CO₂e getting crossed in 2028 due to the forcing of methane alone. 

Even without such an increase in methane, a huge temperature rise could eventuate by 2026, first of all due to a cataclysmic alignment of El Niño and sunspots.

We are currently in the depths of a persistent La Niña, as illustrated by the image on the right, adapted from NOAA, and this suppresses the temperature rise at the moment.

The next El Niño is already overdue, so the peak of the next El Niño may well coincide with a peak in sunspots which look set to reach a higher than expected maximum impact around July 2025. The rise in sunspots from May 2020 to July 2025 could make a difference of some 0.15°C, concluded an earlier post.

Moving from the bottom of the current La Niña to the peak of a strong El Niño could make a difference of more than half a degree Celsius, as indicated by the image below, adapted from NOAA. 


Therefore, the rise due to the combined impact of El Niño and sunspots could be 0.65°C by 2025. When adding this to the temperature rise that has already occurred and that, when measured from pre-industrial could be as high as 2.29°C, the total land-ocean global temperature rise could be as high as 2.94°C by 2025,  while the rise on land on the Northern Hemisphere could peak at more than 3°C above pre-industrial, noting that when there was a strong El Niño in February 2016, the land-only monthly anomaly from 1880-1920 was 2.95°C, as illustrated by the image below. 

[ from earlier post ]
Such a huge rise could cause heatwaves and droughts that could result in a huge peak in power demand, as everyone switches on their air conditioners, while at the same time rivers could either dry up or their water could become too hot to cool power plants. This could bring the grid down, which would mean that coal-fired power plants would stop emitting sulfates.

[ from Track Buckling Research ]
This could mean that equipment and appliances that need electricity such as heaters and air conditioners could stop working. Electric pumps could stop working, so there may no longer be water coming out of taps. The internet could stop working where routers require power from the grid.

Furthermore, the heat could cause asphalt and tarmac to melt and rail tracks to buckle, while airports could be closed, not only because the surface of the runway could get too hot, but also because the air could become too thin for planes to take off due to the heat.

In short, traffic, transport and industrial activities such as smelting, which are emitting a lot of sulfates as well at the moment, could grind to a halt at many places on the Northern Hemisphere. The result would be a large reduction in aerosols that are currently masking the full wrath of global warming (mainly sulfates). 

[ see the Extinction page ]
How much difference could it make? The IPCC in AR6 estimates the aerosol ERF to be −1.3 W m⁻², adding that there has been an increase in the estimated magnitude of the total aerosol ERF relative to AR5. In AR6, the IPCC estimate for liquid water path (LWP, i.e., the vertically integrated cloud water) adjustment is 0.2 W m⁻², but a recent analysis found a forcing from LWP adjustment of −0.76 W m⁻², which would mean that the IPCC estimate of −1.3 W m⁻² should be changed to -2.26 W m⁻². When using a sensitivity of ¾°C per W m⁻², this translates into an impact of -1.695°C. Since the IPCC's total for aerosols includes a net positive impact for warming aerosols such as black carbon, the impact of cooling aerosols only (without warming aerosols) will be even more negative.

This supports the 2016 analysis that warned that by 2026 there could be a 1.9°C temperature rise due to a decrease in cooling aerosols, while there could be an additional 0.6°C temperature rise due to an increase in warming aerosols and gases as a result of more biomass and waste burning and forest fires by 2026.

So, together with the upcoming El Niño and a peak in sunspots, that could result in a total rise by 2026 of 5.44°C above pre-industrial. There's more to come! Additionally, the 2016 analysis warned about further rises in temperature due to loss of Arctic sea ice and permafrost, and associated changes, as well as further rises due to gases, concluding that there could be a temperature rise by 2026 of more than 10°C compared to pre-industrial.

With a temperature rise of more than 10°C by 2026, the clouds tipping point will also be crossed, which would result in a total rise of more than 18°C by 2026. Keep in mind that humans are likely to go extinct with a rise of 3°C, as illustrated by the image below, from an analysis discussed in an earlier post.


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

• WMO - More bad news for the planet: greenhouse gas levels hit new highs 

• WMO - Greenhouse Gas Bulletin 
https://public.wmo.int/en/greenhouse-gas-bulletin

• Ideas and perspectives: is shale gas a major driver of recent increase in global atmospheric methane? - by Robert Howarth

• NOAA - Global Monitoring Laboratory
https://gml.noaa.gov/dv/iadv

• Copernicus methane at 500 hPa, forecast for October 18, 2022, 03 UTC
https://atmosphere.copernicus.eu/charts/cams/methane-forecasts?facets=undefined&time=2022101800,3,2022101803&projection=classical_global&layer_name=composition_ch4_500hpa

• What the IPCC impacts report is hiding
https://arctic-news.blogspot.com/2022/02/what-the-ipcc-impacts-report-is-hiding.html

• Climate Endgame: Exploring catastrophic climate change scenarios - by Luke Kemp et al.
https://www.pnas.org/doi/full/10.1073/pnas.2108146119

Also discussed at:
https://www.facebook.com/groups/arcticnews/posts/10160138721434679

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

• Arctic Ocean invaded by hot, salty water

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

• NOAA National Centers for Environmental Information, State of the Climate: Monthly Global Climate Report for September 2022, retrieved October 16, 2022
https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202209/supplemental/page-4

• 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

• Crossing 3C
https://arctic-news.blogspot.com/2022/09/crossing-3c.html

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

• Track Buckling Research
https://www.volpe.dot.gov/infrastructure-systems-and-technology/structures-and-dynamics/track-buckling-research

• Invisible ship tracks show large cloud sensitivity to aerosol - by Peter Manhausen et al. 

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






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Thursday, September 29, 2022

Crossing 3C

The Northern Hemisphere is where most people live. Furthermore, most people live on land. Let's first look at the temperature rise on the Northern Hemisphere. 

The image below, created with a September 30, 2022 screenshot from NASA customized analysis plots, shows June-July-August temperature anomalies from 1880-1920 on the Northern Hemisphere with June-July-August 2022 highlighted with an anomaly of 1.4°C or 2.52°F, a record high in a tie with 2020. 


Secondly, most people live on land. The image below shows the monthly mean global surface temperature anomaly on land. It is similarly created with a September 30, 2022 screenshot from NASA customized analysis plots and shows a peak anomaly from 1880-1920 of 2.95°C or 5.31°F (for February 2016, land only).


The year 2016 was an El Niño year. During an El Niño, temperatures are higher than usual. We are currently in the depths of a persistent La Niña, which suppresses temperatures. We look set to move into another El Niño within years. 

In conclusion, the temperature rise on land on the Northern Hemisphere looks set to cross 3°C soon, the more so since we are also facing a peak in sunspots (by 2025), which may coincide with peak temperatures associated with the upcoming El Niño. Also keep in mind that the above temperature anomalies are measured from 1880-1920, so the temperature rise from pre-industrial is significantly higher than that. 


There are further events and developments that could additionally speed up the temperature rise, as discussed at the extinction page. Humans are likely to go extinct with a rise of 3°C, as illustrated by the above image, from an analysis discussed in an earlier post.

Methane levels keep rising

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 there also are further events and developments that could additionally speed up the temperature rise, as discussed in earlier posts such as this one. Furthermore, the NOAA data used in the above image rise are for marine surface measurements. Methane is accumulating at higher altitude, as illustrated by the compilation images below. 


The top image of above compilation image shows that the MetOp-B (also known as MetOp-1) satellite recorded a mean methane concentration of 1979 parts per billion (ppb) at 293 mb on September 30, 2022 pm. 

The above compilation image shows high concentrations of methane close to sea level, all the way up to the Tropopause. Does this indicate that methane is rising up from the seafloor of the Arctic Ocean?  

Polar Jet Stream (blue) and Subtropical
Jet Stream (red) - NOAA image
Let's first take a look at prevailing wind pattern and how they changed. On the Northern Hemisphere, the coldest point used to be the North Pole, so wind used to flow from the tropics to the North Pole.

This and the deflection due to the Coriolis force resulted in two Jet Streams forming, circumnavigating the globe in what used to be narrow and straight bands, i.e. the Polar Jet Stream at 60° North and the Subtropical Jet Stream at about 30°, both on the Northern and Southern Hemisphere, resulting in a total of four Jet Streams.

The Jet Stream used to circumnavigate the globe in narrow and straight bands, predominantly following a path from East to West, in line with its strength and with this deflection.

Polar Jet Stream and Subtropical Jet Stream - NOAA image
The Jet Stream used to circumnavigate the globe at specific latitudes, as illustrated by the images on the right.

Prevailing wind patterns cause carbon dioxide to accumulate at the poles, as illustrated by the image underneath on the right that shows a high carbon dioxide concentration of 235 ppm over the North Pole. 

Some things changed as, due to emissions by people, the difference in temperature between the Arctic and the Tropics narrowed. 

This decreases the speed at which heat is moving to the North on the Northern Hemisphere and it deforms the Jet Stream and the prevailing wind patterns, which can make it even more easy for methane that is released from the Arctic Ocean to rise up and accumulate at the Tropopause, and move from there toward the Equator as it rises. 

Emissions by people are also causing the Troposhere to expand. 

Note the important difference in weight between carbon dioxide and methane. Carbon dioxide tends to accumulate at lower altitudes since it is heavier than air. Methane, on the other hand, is lighter than air, causing methane to rise and accumulate at altitudes near the Tropopause, from where methane moves closer to the Equator, since the Tropopause is higher in altitude at the Tropics than at the Poles. 

The accumulation of methane at higher altitudes is further illustrated in the compilation image below that shows that methane mean levels are highest where the troposphere ends over the Arctic. 


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

• NASA - GISS Surface Temperature Analysis
https://data.giss.nasa.gov/gistemp/graphs_v4/customize.html

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

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

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

• When will we die?
https://arctic-news.blogspot.com/2019/06/when-will-we-die.html

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

• Blue Ocean Event 2022?

• Jet Stream

• nullschool.net

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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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