Monday, November 16, 2020

Accelerated global warming and stadial cooling events: IPCC oversights regarding future climate trends

 by Andrew Glikson

The linear nature of global warming projections by the IPCC (2014) Assessment Report (AR5) (Figure 1) appears to take little account of stadial cooling events, such as have followed peak temperature rises in previous interglacial stages. The linear trends appear to take only limited account of amplifying positive feedback effects of the warming from land and ocean. A number of factors cast doubt on IPCC climate change projections to 2100 AD and 2300 AD, including:
Figure 1 (a) IPCC average surface temperature change to 2100 relative to 1986-2005 IPCC AR5;
(b) IPCC average surface temperature change to 2300 relative to 1986-2005 IPCC AR5

However, global temperature measurements for 2015-2020 indicate accelerated warming due to both the greenhouse effect reinforced by a solar radiation maximum (Hansen and Sato 2020) (Figure 2).

Figure 2. Accelerated Global Warming reinforced by both greenhouse 
gases and a solar maximum Hansen and Sato, 2020

The weakening of the northern Jet stream, due to polar warming and thus reduced longitudinal temperature contrasts, allows penetration of warm air masses into the polar region and consequent fires (Figure 3). The clash between tropical and polar air and water masses (Figure 3A) leads to regional storminess and contrasting climate change trajectories in different parts of the Earth, in particular along land-ocean boundaries and island chains. 

The weakening of the jet stream and migration of climate zones constitute manifestations of an evolving Earth’s energy imbalance¹, namely a decrease in reflection of solar radiation from Earth to space and thereby global warming. Earth retained 0.6 Watt/m² during 2005-2010 and 0.87 Watt/m² during 2010-2020 (Hansen and Sato 2020), primarily due to a rise in greenhouse gases but also due to a solar radiation peak. During 2015-2020 global warming rates exceeded the 1970-2015 warming rate of 0.18°C/per decade, a deviation greater than climate variability. Hansen and Sato (2020) conclude the accelerated warming is caused by an increasing global climate forcing, specifically by the role of atmospheric aerosols.

Figure 3 A. Undulating and weakening jet stream and the polar vortex and penetration
of warm air, inducing Arctic warming and fires.     B. Satellite images of Wildfires
ravaging parts of the Arctic
, with areas of Siberia, Alaska, Greenland and Canada
engulfed in flames and smoke. While wildfires are common at this time of year, record-
breaking summer temperatures and strong winds have made 2020 fires particularly bad.

Bronselaer et al., 2018 modelled a meltwater-induced cooling of the southern hemisphere toward the end 21st century by as low as -1.5°C (Figure 4A). Hansen et al. 2016 estimated the time frame of 21st century stadial cooling event as dependent on the rates of ice melt (Figure 4B), reaching near global extent toward the end of the century (Figure 4C).

Figure 4 A. 2080–2100 meltwater-induced sea-air temperature anomalies relative to
the standard RCP8.5 ensemble (Bronselaer et al., 2018). Hatching indicates where the
anomalies are not significant at the 95% level;  B. Negative temperature anomalies
through the 21st-22nd centuries signifying stadial cooling intervals (Hansen et al., 2016);
C. A model of Global warming for 2096, where cold ice melt water occupies large parts
of the North Atlantic and circum-Antarctica, raises sea level by about 5 meters and
decreases global temperature by -0.33°C (Hansen et al., 2016).

With the concentration of greenhouse gases rising by approximately 47% during the last century and a half, faster than almost any observed rise in the Cenozoic geological record, the term “climate change” refers to an extreme shift in state of the atmosphere-ocean system. The greenhouse gas rise and temperature rise rates are faster than those of the K-T mass extinction, the Paleocene-Eocene extinction and the last glacial termination.

The consequences for future climate change trends include:
  • Further expansion of the tropical climate zones and a polar-ward shift of intermediate climate zones, leading to encroachment of subtropical deserts over fertile Mediterranean zones. 
  • Spates of regional to continent-scale fires, including in Brazil, Siberia, California, around the Mediterranean, Australia.
  • A weakened undulating jet stream (Figure 3) allowing penetration of and clashes between warm and cold air and water masses, with ensuing storms. 
  • In Australia the prolonged drought, low vegetation moisture, high temperatures and warm winds emanating from the northern Indian Ocean and from the inland, rendering large parts of the continent tinder dry and creating severe fire weather subject to ignition by lightning.
  • The delayed melting of the large ice sheets due to hysteresis², would be followed by sea level rise to Pliocene levels, ~25 meters above pre-industrial levels, once sea level reaches equilibrium with temperature of 2 to 3 degrees Celsius or higher, changing the geography of the continents.
It would follow from these considerations that succeeding periods of peak temperatures, extensive melting of the ice sheets, flow of ice melt into the oceans and thereby stadial cooling would lead to clashes between tropical fronts and cooling masses of air, producing storminess, in particular along continental margins and island chains. The modelled time frame of these developments (Figure 4B) may be cyclical, or may extend further in time and place as long as the ice sheets continue to breakdown.


¹ Earth's energy imbalance is the difference between the amount of solar energy
absorbed 
by Earth and the amount of energy the planet radiates to space as heat.
If the imbalance is 
positive, more energy coming in than going out, we can expect
Earth to become warmer in t
he future — but cooler if the imbalance is negative.
² Hysteresis is the dependence of the state of a system on its history. For example the 
melting of an ice sheet may occur slowly depending on its previous state.

Andrew Glikson

Dr Andrew Glikson
Earth and Paleo-climate scientist
ANU Climate Science Institute
ANU Planetary Science Institute
Canberra, Australia


Books:
The Asteroid Impact Connection of Planetary Evolution
http://www.springer.com/gp/book/9789400763272
The Archaean: Geological and Geochemical Windows into the Early Earth
http://www.springer.com/gp/book/9783319079073
Climate, Fire and Human Evolution: The Deep Time Dimensions of the Anthropocene
http://www.springer.com/gp/book/9783319225111
The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth
http://www.springer.com/gp/book/9783319572369
Evolution of the Atmosphere, Fire and the Anthropocene Climate Event Horizon
http://www.springer.com/gp/book/9789400773318
From Stars to Brains: Milestones in the Planetary Evolution of Life and Intelligence
https://www.springer.com/us/book/9783030106027
Asteroids Impacts, Crustal Evolution and Related Mineral Systems with Special Reference to Australia
http://www.springer.com/us/book/9783319745442





Wednesday, November 11, 2020

Above Zero Celsius at North Pole November 2020

Above image shows that, in October 2020, the Arctic Ocean was very hot. The Copernicus image below shows temperatures averaged over the twelve-month period from November 2019 to October 2020.

Keep in mind that, in the Copernicus image, anomalies are compared to the 1981-2010 average.

Note that the shape of the recent twelve-month period is similar to the 2016 peak, when there was a strong El Niño, while in October 2020 the temperature was suppressed due to La Niña and due to low sunspots.

The image below shows how a hot Arctic Ocean distorts the Jet Stream and hot air moves all the way up to the North Pole. 

Above image shows the Northern Hemisphere at November 12, 2020, with a temperature forecast of 2.0°C or 35.5°F at the North Pole at 1000 hPa at 15:00Z. On the right, jet stream crosses the Arctic Ocean (at 250 hPa). At surface level, a temperature was forecast to be 0.6°C or 33.2°F. 


As it turned out, the highest temperature at the North Pole was 1.1°C or 34.1°F on November 12, 2020, at 1000 hPa at 18:00Z, as above image shows. At 15:00Z that day, a temperature of 1.9°C or 35.3°F was recorded at 1000 hPa just south of the North Pole, at 89.50° N, 1.50° E.

The image below shows temperature anomalies for November 12, 2020, with forecasts approaching 30°C. 


[ Click on images to enlarge ]
These high temperatures over the Arctic Ocean are caused by transfer of huge amounts of heat from the Arctic Ocean to the atmosphere, indicating severe overheating of the Arctic Ocean as a result of the ongoing movement of ocean heat at the surface of the North Atlantic to the Arctic Ocean along the Gulf Stream. 

As the image on the right shows, temperature anomalies above 20°C were recorded over a large part of the Arctic Ocean on November 16, 2020. 

As illustrated by the image below, temperature anomalies are forecast to remain high over the Arctic Ocean, with the forecast for November 26, 2020, showing anomalies approaching 30°C. 


The resulting distortion of the Jet Stream can at times speed up winds that move hot air from the North Atlantic Ocean toward to Arctic Ocean, as illustrated by the image at the top. 

[ click on images to enlarge ]
The image on the right shows that the Jet Stream was as fast as 411 km/h or 255 mph south of Greenland (at the green circle), before crossing the Arctic Ocean on November 4, 2020. 

The image below shows how, on November 20, 2020 15:00 UTC, a distorted Jet Stream reaches a speed of 327 km/h or 203 mph (at circle, globe left). At 850 hPa, wind reaches speeds as high as 161 km/h or 100 mph (circle, globe right). 

The danger is that such strong wind will speed up ocean currents in the North Atlantic that carry huge amounts of heat toward the Arctic Ocean. 


The image below shows sea surface temperature anomalies compared to 1981-2011 on the Northern Hemisphere on October 23, 2020, when anomalies off the coast of North America were as high as 10.8°C or 19.5°F (left), and on December 3, 2020, when anomalies off the coast of North America were as high as 12.7°C or 22.8°F (right). 


According to a recent news report, an atmospheric river smashed into Juneau, Alaska, dropping 5.08 inches of rain in 24 hours ending 3 a.m. Wednesday December 2, 2020.

This is not an isolated event, but a symptom of the unfolding catastrophe referred to as global warming, which threatens to remove all life from Earth.

Sea surface temperatures around North America are very high. The above image shows that sea surface temperatures were as much as 12.7°C or 22.8°F higher than 1981-2011 off the east coast of North America on December 3, 2020 (green circle). On the image below, the globe on the left shows that sea surface temperature anomalies (SSTA) were as high as 4.1°C or 7.3°F off the west coast of North America on December 4, 2020 (at the green circle).

These high sea surface temperatures speed up de Jet Stream over oceans. At this time of year, temperatures over continents are low, so there is greater ocean/land temperature difference, which further speeds up the Jet Stream where it travels over oceans toward continents. The center globe shows wind as fast as 381 km/h or 237 mph at the time (at circle). 

At the same time, the narrowing temperature difference between the Equator and the North Pole is slowing down the Jet Stream. This is making the Jet Stream more wavy at higher latitudes, even resulting in circular wind patterns, and this can make a lot of cold air leave the Arctic and move over continents, thus further widening the ocean/land temperature difference. Given that more than 90% of global warming goes into oceans, this is an important self-reinforcing feedback of global warming. 

Stronger wind results in stronger evaporation, which cools down the sea surface somewhat, as the blue areas over the Pacific Ocean indicate. Due to the strong wind, much of the moisture falls down farther on the path of the wind. The globe on the right shows 3-hour precipitation accumulation as high as 31.3 mm or 1.23 in off the west coast of North America (green circle). 


The image below shows an earlier analysis, describing the situation in September 6, 2020, when high sea surface temperatures on the Northern Hemisphere and a narrow difference between the Equator and the North Pole distorted the Jet Stream, making it cross the Arctic Ocean, form circular wind patterns and reach speeds as fast as 262 km/h or 163 mph (250 hPa, green circle) over the North Atlantic. The globe on the right shows that the Gulf Stream off the North American coast reached speeds of 8 km/h or 5 mph (at green circle). 

[ click on images to enlarge ]

More ocean heat can move into the Arctic Ocean for a number of reasons, including: 
  • At times, the Jet Stream becomes very strong and elongated over the North Atlantic, speeding up the flow of ocean heat along the path of Gulf Stream all the way to the Arctic Ocean;
  • Overall, winds are getting stronger, speeding up ocean currents running just below the sea surface;
  • Stratification of the North Atlantic results in less heat mixing down to lower parts of the ocean; and 
  • Increased evaporation and increased subsequent rainfall farther down the path of the Gulf Stream forms a colder freshwater lid stretched out at the sea surface from the North Atlantic to the Arctic Ocean, sealing off transfer of heat from ocean to atmosphere and consequently moving more heat just underneath the sea surface into the Arctic Ocean.

    [ from earlier post ]
As the image below shows, sea surface temperatures as high as 16.6°C or 61.9°F were recorded north of Svalbard on November 9, 2020. 


As the image below shows, the N2O satellite recorded a peak methane level of 2762 ppb on the morning of November 16, 2020.


As the image below shows, the MetOp-1 satellite recorded a peak methane level of 2725 ppb on the afternoon of November 18, 2020.


The video below shows a methane plume or bubble cloud spotted by a team of 69 scientists from ten countries documenting bubble clouds rising from a depth of around 300 metres (985ft) along a 150km (93 mile) undersea slope in the Laptev Sea.


The danger is that even more hot and salty water will reach the shallow parts of the Arctic Ocean that contain huge amounts of methane in the form of hydrates and free gas in sediments at the seafloor, resulting in huge eruptions of methane that, on its own, could almost instantly cause the 1200 ppm CO₂e cloud feedback tipping point to be crossed, which can cause global temperatures to rise by 8°C.

Latent heat loss, feedback #14 on the Feedbacks page

The situation is dire and calls for comprehensive and effective action, as discussed in the Climate Plan.


Links

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

• NASA GISS Surface Temperature Analysis - global maps

• Copernicus - surface air temperature for October 2020

• Climate Reanalyzer

• nullschool earth wind map

• Atmospheric River Smashes Alaskan Capital’s 24-Hour Rain Record

• Bubbling methane craters and super seeps - is this the worrying new face of the undersea Arctic? - by Valeria Sukhova, Olga Gertcyk - Siberian Post

• Why stronger winds over the North Atlantic are so dangerous

• Feedbacks in the Arctic

• September 2015 Sea Surface Warmest On Record

Monday, October 19, 2020

Earthquake hits Alaska October 19, 2020


An earthquake with a magnitude of 7.5 on the Richter scale hit Alaska (blue circle on map) on October 19, 2020 8:54 pm UTC.

The image shows a screenshot taken October 19, 2020 11:30 pm UTC featuring earthquakes over the past 7 days, with the M7.5 earthquake showing up in blue and the other earthquakes colored by age, i.e. hour (red), day (orange) and week (yellow). 

Such huge earthquakes can cause tsunamis.

In the Arctic, such huge earthquakes also come with the danger that they will destabilize methane hydrates at the seafloor which can cause huge amounts of methane to erupt. Shockwaves can travel along faults and cause eruptions at places far away from where the original eathquake occurred. 

Ominously, the MetOp-1 satellite recorded methane levels as high as 2618 ppb on the morning of October 22, 2020 at 586 mb. 


On the afternoon of October 23, 2020, the SNPP satellite recorded methane levels as high as 2735 ppb at 487.2 mb. 



The situation is dire and calls for immediate, comprehensive and effective action, as described in the Climate Plan.


Links

• USGS - M 7.5 - 91 km SE of Sand Point, Alaska - 2020-10-19 20:54:40 (UTC)
https://earthquake.usgs.gov/earthquakes/eventpage/us6000c9hg/executive

• USGS - Earthquakes map
https://earthquake.usgs.gov/earthquakes/map

• Seismic Events
https://arctic-news.blogspot.com/p/seismic-events.html

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

Tuesday, October 13, 2020

High Temperatures October 2020


September 2020 was the warmest September in the NASA record that goes back to 1880. In the image, September 2020 temperatures are compared to 1951-1980.

Global warming is accelerating

Similarly, Copernicus reports that September 2020 global surface air temperature was the highest September temperature on record. The image below shows temperatures averaged over the twelve-month period from October 2019 to September 2020.

Keep in mind that anomalies in the NASA image are compared to 1951-1980, while in the Copernicus image, anomalies are compared to the 1981-2010 average. Anomalies are even higher when compared to pre-industrial levels, as discussed further below.

The Copernicus image shows that the shape of the global anomaly over the past twelve months is very similar to the peak reached around 2016. This confirms that global warming is accelerating, because the peak around 2016 was reached under El Niño conditions, whereas current temperatures are reached under La Niña conditions and while sunspots are at a low, both of which are suppressing temperatures, as discussed in a recent post

What causes this acceleration of the temperature rise?

James Hansen and Makiko Sato confirm that global warming is accelerating and they explore whether this acceleration could be caused by fast feedbacks and short-term natural variability such as the sunspot solar cycle, which they give an amplitude of some 0.25 W/m². James Hansen and Makiko Sato conclude that global warming is accelerating due to a less negative atmospheric aerosol forcing.

Indeed, sunspots cannot explain this acceleration, because we're currently in a sunspot low. 


El Niño/La Niña cannot explain this acceleration either, because we're currently experiencing La Niña conditions, as also illustrated by above NOAA image

Further causes could be explored. As the image below shows, more than 90% of global warming currently goes into oceans. 

[ see also earlier post ]

The two images below shows that high sea surface temperature anomalies feature on the Northern Hemisphere on October 22, 2020, with anomalies (from 1981-2011) as high as 10.2°C or 18.3°F (off the coast of North America). This is the more remarkable since, at the same time, low sea surface temperatures show up over the mid-Pacific, associated with La Niña (image right). 



Stratification may cause oceans to take up less heat and the more heat will remain in the troposphere, the faster the temperature of the troposphere will rise, as discussed in an earlier post

As discussed under feedback #25 at the feedbacks page, the atmosphere can be expected to carry more water vapor as temperatures rise. Since water vapor is a potent greenhouse gas, more water vapor in the atmosphere will contribute to global warming. 

More evaporation also brings more heat into the atmosphere, as illustrated by the image on the right, and more heat will also be transferred to the atmosphere as the area of open water increases in the Arctic Ocean.

Further acceleration of the temperature rise

[ from earlier post ]
Further acceleration of global warming looks set to occur over the next few years as sunspot activity increases and as El Niño conditions will return. 

In 2019, Tiar Dani et al. analyzed a number of studies and forecasts pointing at the maximum in the upcoming Solar Cycle occurring in the year 2023 or 2024.

This analysis, discussed in a recent post, found some variation in intensity between forecasts, adding images including the one on the right, which is based on linear regression and suggests that the Solar Cycle 25 may be higher than the previous Solar Cycle 24. 

The need to rapidly transition to clean, renewable energy 

The international treaty banning nuclear weapons has now been ratified by 50 countries and the treaty will come into force on 22 January 2021, making it illegal to stockpile, produce and use nuclear weapons from January 22, 2021.

The treaty complements the Paris Agreement, the Montreal Protocol and further international agreements that politicians should abide by.

Clean, renewable energy - key to world peace

In the year 1900, there were more electric cars on U.S. roads than gasoline cars. Solar panels were used on a satellite, launched by the US back in 1958. William Thomson proposed using heat pumps for space heating in 1852. The first electricity-generating wind turbine was invented in 1888 in Cleveland, Ohio by Charles Brush.

What has been holding up the innovation in clean, renewable energy technologies such as batteries, solar panels, wind turbines and heat pumps? What stood in the way was the disastrous turn that history took into fossil fuel and nuclear power. Historically, fossil fuel has been a source of conflict that blocked the road to progress. The key to progress and world peace is a rapid transition to clean, renewable energy.

Fossil fuel and control over its supply is behind much of the conflict and violence, as well as pollution that has infested the world for more than a century. Instead of continuing to use fossil fuel, the world must rapidly transition to the use wind turbines, geothermal power, solar power, wave power, and similar ways to generate clean, renewable energy, in combination with hydrogen and batteries and other ways to store energy.

Abundance of local clean, renewable energy

This transition to clean, renewable energy will remove much cause for conflict. Clean, renewable energy is available in abundance LOCALLY around the world (unlike fossil fuel) and the use of clean, renewable energy in one place doesn't exclude use of clean, renewable energy elsewhere.

Clean, renewable energy's numerous benefits

This transition also comes with greater energy security and reliability, next to its numerous further benefits, e.g. it will make more land and water available for growing food and it will generate better and more jobs and investment opportunities, and improve our health, in addition to the reductions in greenhouse gases that come with this transition.

Clean, renewable energy is also cheaper

Importantly, it is also more economic to use clean, renewable energy, so the transition will more than pay for itself as we go. The more prices of solar panels, batteries, heat pumps, etc. keep falling, and the more urgency there is to act on climate change, the more sense it makes to transition to clean, renewable energy as soon as possible. Innovation has resulted in a huge drop in the cost of generating and storing clean, renewable electricity. In the Lazard 2019 analysis of the cost of energy and storage, the unsubsidized cost of solar PV (thin film utility scale) was $US32-42/MWh, i.e. already lower than the cost of fossil fuel and nuclear, which ranged from $US44-199/MWh (see image). A recent tender for solar panels in Portugal received an offer equivalent to a price of $US13/MWh. 

Aerosols
 
Yet, while the transition to clean, renewable energy makes sense from so many perspectives, while it is absolutely necessary, and while it will reduce temperatures, this transition will not immediately result in lower overall temperatures, for a number of reasons. Maximum warming occurs about one decade after a carbon dioxide emission, so the full warming wrath of the carbon dioxide emissions over the past ten years is still to come, as discussed at the extinction page. Even with dramatic cuts in emissions, temperatures will not fall as long as levels of greenhouse gases in the atmosphere remain high. Additionally, sulfate cooling loss will further increase temperatures, as the world progresses with the necessary transition to the use of clean, renewable electricity. So, additional action is needed! 

A rapid, steep temperature rise

The danger is that a rapid and steep temperature rise will be triggered by a combination of elements such as El Niño, sunspots, oceans taking up less heat and changes to aerosols such as further sulfate cooling loss. 

The potential for such a rapid, steep temperature rise is also illustrated by the image below, posted in February 2019 and showing a potential total rise of 18°C or 32.4°F from 1750 by the year 2026.

[ from earlier post ]

A rapid, steep temperature rise would be felt most strongly in the Arctic, causing albedo loss, emissions and transfer of heat from ocean to atmosphere that would all hit the Arctic most strongly, thus further speeding up the temperature rise, as also illustrated by the image below. 


As discussed in an earlier post, a rise of more than 5°C could happen within a decade, possible by 2026. Humans will likely go extinct with a 3°C rise and most life on Earth will disappear with a 5°C rise. 

[ from earlier post ]

Arctic Sea Ice

Meanwhile, temperatures in the Arctic have been very high, as illustrated by the image below showing air temperature in the Arctic up to October 12, 2020 (red line). 


For some time, Arctic sea ice exent has been at a record low for the time of year, as illustrated by the image below, showing the situation on October 20, 2020. 


For some time, sea ice area has also been at a record low for the time of year, as illustrated by the image below, showing the situation up to October 22, 2020.


Arctic sea ice volume has been very low, as illustrated by the image below showing volume up to September 30, 2020. 


As the image below shows, there was a lot of open water north of Greenland on October 23, 2020.


The image below, showing land outlines, is added for reference purposes. See also further images at this facebook post.


Temperature anomalies over the Arctic Ocean remain high. The image below shows a forecast for November 8, 2020 12Z. Very high temperature anomalies are visible over the Arctic Ocean, in particular over the East Siberian Arctic Shelf, while the Arctic as a whole shows an anomaly of 6.1°C compared to 1979-2000.


These high temperature anomalies reflect overheating of the Arctic Ocean with the sea ice no longer acting as a buffer to consume heat.

Furthermore, these high temperatures in October and November 2020 reduce the chances that sea ice will build up much thickness over the next few months, meaning there will be little or no buffer to consume incoming heat as temperatures start to rise again early next year. 

Without such a buffer, and with greater odds of high temperatures at the start of the melting season, the threat increases of destabilization of methane hydrates contained in sediments at the seafloor of the Arctic Ocean. 

Meanwhile, the temperature of the ocean on the Northern Hemisphere keeps increasing, as illustrated by the image below, from an earlier post


As the Arctic warms up faster than the rest of the world, the temperature difference between the North Pole and the Equator narrows, making the jet stream wavier, thus enabling warm air over the Pacific Arctic to move more easily into the Arctic, as discussed in many earlier posts such as this one, which featured a forecast for March 31, 2019, with a temperature anomaly for the Arctic of 7.7°C or 13.86°F and local anomalies approaching 30°C or 54°F higher than 1979-2000.

So, the odds are increasing that very high temperatures will hit the Arctic at the start of the melting season, further increasing the threat of destabilization of methane hydrates contained in sediments at the seafloor of the Arctic Ocean. 

The Methane Threat

On October 26, 2020 pm, the NetOp-1 satellite recorded methane levels as high as 2537 ppb. 

Where did such high levels originate? The animation shows areas solidly magenta-colored and indicating high methane levels to first appear over the East Siberian Arctic Shelf close to sea level, and to grow larger and cover more of the Arctic Ocean at higher altitudes. 

As discussed repeatedly in earlier posts such as this one and as illustrated by the image below, from a recent post, methane levels are rising most strongly at higher altitudes. 

[ from earlier post ]

As discussed in a 2017 post, methane eruptions from the Arctic Ocean can be missed by measuring stations that are located on land and that often take measurements at low altitude, thus missing the methane that rises in plumes from the Arctic Ocean. Since seafloor methane is rising in plumes, it hardly shows up on satellite images at lower altitude either, as the methane is very concentrated inside the area of the plume, while little or no increase in methane levels is taking place outside the plume. Since the plume will cover less than half the area of one pixel, such a plume doesn't show up well at low altitudes on satellite images.

Over the poles, the Troposphere doesn't reach the heights it does over the tropics. At higher altitudes, methane will follow the Tropopause, i.e. the methane will rise in altitude while moving closer to the Equator.

Methane rises from the Arctic Ocean concentrated in plumes, pushing away the aerosols and gases that slow down the rise of methane elsewhere, which enables methane erupting from the Arctic Ocean to rise straight up fast and reach the stratosphere. Since little hydroxyl is present in the atmosphere over the Arctic, it is much harder for this methane to be broken down. 

What further makes the rise of methane at these high altitudes very worrying is that once methane does reach the stratosphere, it can remain there for a long time. The IPCC in 2013 (AR5) gave methane a lifetime of 12.4 years. The IPCC in 2001 (TAR) gave stratospheric methane a lifetime of 120 years, adding that less than 7% of methane did reach the stratosphere.

Conclusion

The situation is dire and calls for immediate, comprehensive and effective action, as described in the Climate Plan.


Links

• Copernicus - Surface air temperature for September 2020
https://climate.copernicus.eu/surface-air-temperature-september-2020

• NASA - Temperature anomalies September 2020
https://data.giss.nasa.gov/gistemp/maps/index.html

• September 2020 Global Temperature Update - by James Hansen
http://www.columbia.edu/~mhs119/Temperature/Emails/September2020.pdf

• Accelerated Global Warming (14 October 2020) - by James Hansen and Makiko Sato
http://www.columbia.edu/~jeh1/mailings/2020/20201014_AcceleratedWarming.pdf

• NOAA - Global monthly temperature anomalies, with ENSO status
https://www.ncdc.noaa.gov/sotc/global/202009/supplemental/page-4

• ENSO: Recent Evolution, Current Status and Predictions - NOAA, October 12, 2020
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

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

• Climate reanalyzer
https://climatereanalyzer.org

• Cryospherecomputing - by Nico Sun 
http://cryospherecomputing.tk

• Arctic sea ice extent - Vishop, Arctic Data archive System, National Institute of Polar Research, Japan 
https://ads.nipr.ac.jp/vishop/#/extent

• Portugal’s second solar PV tender sets new world record low price

• Lazard 2019 analysis of the cost of energy and storage 
https://www.lazard.com/perspective/lcoe2019

• UN Secretary-General's Spokesman - on the occasion of the 50th ratification of the Treaty on the Prohibition of Nuclear Weapons 
https://www.un.org/sg/en/content/sg/statement/2020-10-24/un-secretary-generals-spokesman-the-occasion-of-the-50th-ratification-of-the-treaty-the-prohibition-of-nuclear-weapons

• Temperatures threaten to become unbearable
https://arctic-news.blogspot.com/2020/09/temperatures-threaten-to-become-unbearable.html 

• Methane Hydrates Tipping Point threatens to get crossed
https://arctic-news.blogspot.com/2017/04/10c-or-18f-warmer-by-2021.html

• A Global Temperature Rise Of More than Ten Degrees Celsius By 2026?