Showing posts with label ocean. Show all posts
Showing posts with label ocean. Show all posts

Thursday, July 27, 2023

Record high North Atlantic sea surface temperature

On July 25, 2023, the North Atlantic sea surface reached a record high temperature of 24.9°C. The previous record was in early September 2022, when the temperature peaked at 24.89°C, according to NOAA scientist Xungang Yin and as illustrated by the image below. 

In previous years, a La Niña was suppressing temperatures, whereas El Niño is now pushing up temperatures. Arctic sea ice typically reaches its minimum extent about half September. We are facing huge sea ice loss over the coming weeks.

Temperatures are very high (and rising) and the following eight points contribute to this rise:

1. Emissions are high and greenhouse gas levels keep rising, and this is increasing Earth's Energy Imbalance. Oceans take up 89% of the extra heat.

2. El Niño is pushing up temperatures, whereas in previous years La Niña was suppressing temperatures. Moving from the bottom of a La Niña to the peak of a strong El Niño could make a difference of more than half a degree Celsius, as discussed in an earlier post.

In February 2016, when there was a strong El Niño, the temperature on land was 3.28°C (5.904°F) hotter than 1880-1896, and 3.68°C (6.624°F) hotter than February 1880 on land. Note that 1880-1896 is not pre-industrial, the difference will be even larger when using a genuinely pre-industrial base.

The above image, from an earlier post discussing extreme heat stress, adds a poignant punchline: Looking at global averages over long periods is a diversion, peak temperature rise is the killer!

[ click on images to enlarge ]
3. Sunspots in June 2023 were more than twice as high in number as predicted, as illustrated by the image on the right, from an earlier post and adapted from NOAA.

If this trend continues, the rise in sunspots forcing from May 2020 to July 2025 may well make a global temperature difference of more than 0.25°C, a recent analysis found.

4. A submarine volcano eruption near Tonga in January 2022 did add a huge amount of water vapor to the atmosphere, as discussed in an earlier post and also at facebook.

Since water vapor is a potent greenhouse gas, this further contributes to speeding up the temperature rise. A 2023 study calculates that the eruption will have a warming effect of 0.12 Watts/m² over the next few years.

5. Aerosol changes are also contributing to the temperature rise, such as less Sahara dust than usual and less sulfur aerosols that are co-emitted with fossil fuel combustion, which previously masked the full impact of greenhouse gases.

6. The Jet Stream is getting increasingly deformed as the temperature difference between the Arctic and the Tropics narrows, and this can strongly increase the intensity, duration and frequency of extreme weather events in the Northern Hemisphere. 

The image on the right shows North Atlantic sea surface temperatures as much as 8.2°C or 14.7°F higher than 1981-2011 (green circle) on July 24, 2023. The image also shows that the Jet Stream is very deformed and features many circular patterns that contribute to stronger heating up of the North Atlantic, especially along the path of the Gulf Stream where the Jet Stream has a strong presence.

Deformation of the Jet Stream can also lead to stronger heatwaves on land that extend over the Arctic Ocean, which in turn can also strongly heat up the water of rivers that end in the Arctic Ocean. The image on the right shows huge amounts of heat surrounding Arctic sea ice and also shows that on July 28, 2023, the sea surface was as much as 19.7°C or 35.4°F hotter than 1981-2011 at an area where the Ob River meets the Kara Sea (green circle).

7. AMOC (the Atlantic meridional overturning circulation) is slowing down, further contributing to more hot water accumulating in the North Atlantic. Instead of reaching the Arctic Ocean gradually, a huge part of this heat that is now accumulating in the
North Atlantic may abruptly be pushed into the Arctic Ocean by strong storms that gain strength as the Jet Stream gets increasingly deformed. This danger grows as more ocean heat is accumulating in the North Atlantic and this situation threatens to cause huge eruptions of methane from the seafloor. 

8. Increased stratification, as temperatures rise, combines with increased meltwater and with stronger evaporation over the North Atlantic and stronger precipitation further down the path of the Gulf Stream. This threatens to result in the formation of a freshwater lid on top of the North Atlantic, enabling more hot water to flow underneath this lid into the Arctic Ocean, further increasing the methane threat.


Arctic reaches record high air temperature

The Arctic reached a record high 2-meter air temperature of 5.81°C on July 27, 2023, almost 2°C higher than the daily mean for the period 1979-2000, as illustrated by the image below. Arctic sea ice typically reaches its minimum extent half September, when the temperature in the Arctic falls below 0°C and water at the surface starts refreezing. 


One danger is that, as more heat is reaching sediments at the seafloor of the Arctic Ocean, hydrates will be destabilized, resulting in eruption of huge amounts of methane from the seafloor.

As sea ice melts away, less sunlight gets reflected back into space, so more heat will reach the Arctic ocean and heat up the water, as discussed at the albedo page.

Furthermore, Arctic sea ice is already very thin, as illustrated by the image on the right. The thinner the sea ice, the less heat can be consumed in the process of melting the ice, as discussed at the latent heat page.

These are just three out of numerous developments that could unfold in the Arctic soon, such as tipping points getting crossed and feedbacks starting to kick in with greater ferocity, as discussed in an earlier post.

Latent heat loss, feedback #14 on the Feedbacks page

Feedbacks

Syee Weldeab et al., in a 2022 study, looked at the early part (128,000 to 125,000 years ago) of the penultimate interglacial, the Eemian, when meltwater from Greenland caused a weakening of the Atlantic meridional overturning circulation (AMOC). “What happens when you put a large amount of fresh water into the North Atlantic is basically it disturbs ocean circulation and reduces the advection of cold water into the intermediate depth of the tropical Atlantic, and as a result warms the waters at this depth,” he said. “We show a hitherto undocumented and remarkably large warming of water at intermediate depths, exhibiting a temperature increase of 6.7°C from the average background value,” Weldeab said.

Weldeab and colleagues used carbon isotopes (13C/12C) in the shells of microorganisms to uncover the fingerprint of methane release and methane oxidation across the water column. “This is one of several amplifying climatic feedback processes where a warming climate caused accelerated ice sheet melting,” he said. “The meltwater weakened the ocean circulation and, as a consequence, the waters at intermediate depth warmed significantly, leading to destabilization of shallow subsurface methane hydrates and release of methane, a potent greenhouse gas.”

Furthermore, more methane over the Arctic would push up temperatures locally over the Arctic Ocean as well as over permafrost on land. A 2020 study by Turetsky et al. found that Arctic permafrost thaw plays a greater role in climate change than previously estimated.

Ominously, some very high methane levels were recorded recently at Barrow, Alaska, as illustrated by the NOAA image below.
Further feedbacks can make the situation even more threatening. As an example, dissolved oxygen in oceans decreases as the temperature rises, further pushing up the temperature rise, as discussed, e.g., in a 2022 study by Jitao Chen et al. As the temperature rises, soil moisture content decreases, further pushing up temperatures, as discussed in an earlier post.

Conclusion

The situation is dire and is getting more dire every day, which calls for a Climate Emergency Declaration and implementation of comprehensive and effective action, as described in the Climate Plan with an update at Transforming Society.


Links

• N. Atlantic ocean temperature sets record high: US agency

• Nullschool
https://earth.nullschool.net

• Climate Reanalyzer - sea surface temperature
https://climatereanalyzer.org/clim/sst_daily

• Copernicus
https://climate.copernicus.eu

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

• A Prehistoric Climate Feedback Loop - Paleoclimatologist uncovers an ancient climate feedback loop that accelerated the effects of Earth's last warming episode (news release)
Evidence for massive methane hydrate destabilization during the penultimate interglacial warming - by Syee Weldeab et al. (study, 2022)

• Marine anoxia linked to abrupt global warming during Earth’s penultimate icehouse - by Jitao Chen et al. (2022)

• Carbon release through abrupt permafrost thaw - by Merritt Turetsky et al. (2020)
• NOAA - Global Monitoring Laboratory - Barrow, Alaska
https://gml.noaa.gov/dv/iadv/graph.php?code=BRW&program=ccgg&type=ts


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

• Will there be Arctic sea ice left in September 2023?
• Dire situation gets more dire every day
https://arctic-news.blogspot.com/2023/07/dire-situation-gets-more-dire-every-day.html

• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html





Posted by at
Labels: , , , , , , , , , ,

Friday, June 30, 2023

Arctic sea ice under threat - update 5

The NASA Worldview satellite image below shows Arctic sea ice on June 29, 2023, with the North Pole on the left. 


The animation below shows that, while clouds can obscure a closer look, sea ice is clearly very thin with the thickest ice breaking up near the top of Greenland, some 750 km from the North Pole. 


The Uni of Bremen image below shows Arctic sea ice thickness on June 28, 2023.


The danger is that, as El Niño strengthens, there will be massive loss of Arctic sea ice over the coming months, with water in the Arctic Ocean heating up strongly due to loss of the latent heat buffer and loss of albedo, while huge amounts of ocean heat keep entering the Arctic Ocean from the Atlantic Ocean and the Pacific Ocean.

The image below shows that the North Atlantic sea surface temperature was 23.5°C on June 28, 2023 (on the black line), 0.9°C higher than the 22.6°C on June 28, 2022 (on the orange line). A record high of 24.9°C was reached on Sept. 4, 2022, even while La Niña was suppressing the temperature. This time, there's an El Niño. 


The image below, adapted from NOAA, shows ocean heat moving toward the Arctic along the path of the Gulf Stream on June 25, 2023, while sea surface temperatures on the map are as high as 32.6°C.


In addition, the Jet Stream is strongly deformed, and this threatens to strengthen heatwaves extending over the Arctic Ocean and causing hot water from rivers to enter the Arctic Ocean, and to strengthen storms accelerating the flow of ocean heat into the Arctic Ocean, while fires and storms contribute to darkening of the sea ice, further speeding up its demise.

The danger is that, as El Niño strengthens and as ocean heat keeps entering the Arctic Ocean from the Atlantic Ocean and the Pacific Ocean, a huge amount of heat will abruptly be pushed into the Arctic Ocean.

This danger is illustrated by the image on the right, from an earlier post, showing the Jet Stream pushing wind at a speed of 126 km/h (78 mph) up through Fram Strait (at the green circle) into the Arctic Ocean on June 21, 2023.

This situation threatens to cause massive loss of Arctic sea ice over the coming months, with water in the Arctic Ocean heating up strongly due to loss of the latent heat buffer and loss of albedo.

This in turn threatens to trigger methane eruptions from the seafloor of the Arctic Ocean, a threat that has been described many times before, such as here, here and here.

[ Latent heat loss, feedback #14 on the Feedbacks page ]
[ see the Extinction page ]
Loss of Arctic sea ice albedo, loss of the latent heat buffer and eruption of seafloor methane all constitute tipping points that threaten to abruptly accelerate the temperature rise in the Arctic, further speeding up loss of permafrost in Siberia and North America and thus threatening to trigger further releases of greenhouse gases.

In addition, there are further events and developments that could unfold and make things even worse.

The upcoming temperature rise on land on the Northern Hemisphere could be of such a severity that much traffic, transport and industrial activity will grind to a halt, resulting in a reduction in cooling aerosols that are now masking the full wrath of global heating. Without these cooling aerosols, the temperature is projected to rise strongly, while there could be an additional temperature rise due to an increase in warming aerosols and gases as a result of more biomass and waste burning and forest fires. Furthermore, as traffic slows down, there will be less nitrogen oxide emissions, which could result in less hydroxyl to curtail methane.

The bar on the right depicts the threat, as discussed at the Extinction page.

In conclusion, the situation is dire and calls for support for a Climate Emergency Declaration.


Links

• Arctic sea ice under threat

• Arctic sea ice under threat - update 1

• Arctic sea ice under threat - update 2

• Arctic sea ice under threat - update 3
https://arctic-news.blogspot.com/2023/06/arctic-sea-ice-under-threat-update-3.html

• Arctic sea ice under threat - update 4
https://arctic-news.blogspot.com/2023/06/arctic-sea-ice-under-threat-update-4.html

• Climate Reanalyzer - Daily sea surface temperatures
https://climatereanalyzer.org/clim/sst_daily

• NOAA - The National Centers for Environment Prediction Climate Forecast System Version 2  

• NOAA - Climate Prediction Center - ENSO Diagnostic Discussions
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

• NOAA - sea surface temperature
https://www.ospo.noaa.gov/Products/ocean/sst/contour/index.html

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

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


Posted by at
Labels: , , , , , , , ,

Friday, June 23, 2023

Arctic sea ice under threat - update 4

The image below, created by Eliot Jacobson, shows the North Atlantic sea surface temperature anomaly through June 20, 2023 (versus 1982-2023 mean).

The image below, created by Eliot Jacobson, shows the North Atlantic sea surface temperature on June 21, for the years 1982-2023.

The image below shows that the North Atlantic sea surface temperature was 23.3°C on June 21, 2023 (on the black line), 0.9°C higher than the 22.4°C on June 21, 2022 (on the orange line). A record high of 24.9°C was reached on September 4, 2022, even while La Niña then was suppressing the temperature, whereas now there's an El Niño.

[ click on images to enlarge ]

Global sea ice extent was at a record low for the time of year on June 23, 2023, i.e. only 21.57 million km², as illustrated by the image below.

[ click on images to enlarge ]

Contributing to this is very low Antarctic sea ice extent. The image below shows Antarctic sea ice extent up to June 23, 2023. Values in the column on the left are for February 16; Antarctic sea ice extent reached a record minimum on February 16, 2023. Values in the column on the right are for June 23. Highlighted are three years: 2023 (red), 2022 (blue) and 2016 (black). Antarctic sea ice extent was also very low at the end of the year 2016, which was a strong El Niño year, yet extent was even lower at the very end of the year in 2022, even though that was during a La Niña.


The image on the right, adapted from NOAA, shows ocean heat moving toward the Arctic along the path of the Gulf Stream on June 21, 2023, while sea surface temperatures on the map are as high as 32.5°C.

In addition, the Jet Stream is strongly deformed, and this threatens to strengthen heatwaves extending over the Arctic Ocean and causing hot water from rivers to enter the Arctic Ocean, and to strengthen storms accelerating the flow of ocean heat into the Arctic Ocean, while fires and storms contribute to darkening of the sea ice, further speeding up its demise.

The danger is that, as El Niño strengthens and as ocean heat keeps entering the Arctic Ocean from the Atlantic Ocean and the Pacific Ocean, a huge amount of heat will abruptly be pushed into the Arctic Ocean. 

This danger is illustrated by the image on the right, showing the Jet Stream pushing wind at a speed of 126 km/h (78 mph) up through Fram Strait (at the green circle) into the Arctic Ocean on June 21, 2023.

This situation threatens to cause massive loss of Arctic sea ice over the coming months, with water in the Arctic Ocean heating up strongly due to loss of the latent heat buffer and loss of albedo.

This in turn threatens to trigger methane eruptions from the seafloor of the Arctic Ocean, a threat that has been described many times before, such as here, here and here.

[ Latent heat loss, feedback #14 on the Feedbacks page ]
[ see the Extinction page ]
Loss of Arctic sea ice albedo, loss of the latent heat buffer and eruption of seafloor methane all constitute tipping points that threaten to abruptly accelerate the temperature rise in the Arctic, thus also further speeding up loss of permafrost in Siberia and North America and thus threatening to trigger further releases of greenhouse gases.

In addition, there are further events and developments that could unfold and make things even worse.

The upcoming temperature rise on land on the Northern Hemisphere could be of such a severity that much traffic, transport and industrial activity will grind to a halt, resulting in a reduction in cooling aerosols that are now masking the full wrath of global heating. Without these cooling aerosols, the temperature is projected to rise strongly, while there could be an additional temperature rise due to an increase in warming aerosols and gases as a result of more biomass and waste burning and forest fires. Furthermore, as traffic slows down, there will be less nitrogen oxide emissions, which could result in less hydroxyl to curtail methane.

The bar on the right depicts the threat, as discussed at the Extinction page.

In conclusion, the situation is dire and calls for support for a Climate Emergency Declaration.


Links

• Arctic sea ice under threat

• Arctic sea ice under threat - update 1

• Arctic sea ice under threat - update 2

• Arctic sea ice under threat - update 3

• Eliot Jacobson - North Atlantic sea surface temperature anomaly through June 20, 2023

• Eliot Jacobson - North Atlantic sea surface temperature on June 21, for the years 1982-2023
https://twitter.com/EliotJacobson/status/1672232859409723392/photo/1

• Climate Reanalyzer - Daily sea surface temperatures
https://climatereanalyzer.org/clim/sst_daily

• NOAA - The National Centers for Environment Prediction Climate Forecast System Version 2  

• NOAA - Climate Prediction Center - ENSO Diagnostic Discussions
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

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

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

• Wetland emission and atmospheric sink changes explain methane growth in 2020 - by Sushi Peng et al. 

• NOAA - sea surface temperature

• Nullschool.net

• Latent Heat

• Albedo

• Extinction

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

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html




Posted by at
Labels: , , , , , , , ,

Friday, April 14, 2023

Temperatures rising fast March 2023

Monthly Northern Hemisphere Land Temperature Anomaly

Temperatures have been rising fast in March 2023. The image below shows the Monthly Northern Hemisphere Land Temperature Anomaly up to March 2023, with two trends added. The blue trend, based on Jan.1850-Mar.2023 NOAA data, points at a 3°C rise in 2032. The magenta trend, based on Oct.2010-Mar.2023 NOAA data, better reflects variables such as El Niño and sunspots, and illustrates how they could trigger a rise of more than 5°C in 2026. Anomalies are versus 1901-2000 (not versus pre-industrial). 


Could it be possible for the temperature to keep following the magenta trend? Let's have a look at how dire the situation is.

Greenhouse gas concentrations keep rising

Reducing emissions is the right thing to do, even though it comes with loss of the aerosol masking effect, a loss that causes a rise in temperatures, as discussed in an earlier post. Yet, despite pledges by politicians, greenhouse gas concentrations in the atmosphere keep rising, as discussed earlier, such as in this post.
The above image illustrates that carbon dioxide (CO₂) was at a record high at Mauna Loa, Hawaii, in three ways: 
  • Daily Record: CO₂ was 424.83 ppm on April 17, 2023;
  • Weekly Record: Average CO₂ was 422.88 ppm for the week beginning April 9, 2023; and
  • Monthly Record: CO₂ in March 2023 was 421 ppm.
CO₂ typically reaches its annual high in May or June, so these records can be expected to be broken over the next few months. 
[ from earlier post ]

Crucially, methane emissions should be cut. The Clouds Tipping Point, at 1200 ppm CO₂e, could be crossed as early as in 2027 due to forcing caused by the rise in methane alone, and crossing this tipping point on its own could result in a further rise of 8°C. When further forcing than the forcing just from methane is taken into account, this could happen even earlier than in 2027.

El Niño and further variables

[ click on images to enlarge ]
Meanwhile, we're moving into an El Niño, as illustrated by the image on the right, adapted from NOAA.

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

NOAA has issued an El Niño Watch, and the range of possibilities toward the end of the year includes a strong El Niño (4 in 10 chance of Niño-3.4 ≥ 1.5°C) to no El Niño (1 in 10 chance).


As illustrated by the image below, the difference in temperature between November 2022 and March 2023 already is about half a degree Celsius and we are not even in an El Niño yet.


El Niño is expected to reach its full strength within a few years, with a maximum possible in 2026.

Furthermore, sunspots look set to reach a high maximum within years, and the 2022 Tonga submarine volcano eruption did add a huge amount of water vapor to the atmosphere, as discussed in an earlier post.

Ocean heat, feedbacks and tipping points

This year (2023), the sea surface temperature (60°S-60°N) has already been above 21°C for 27 days. Such temperatures are unprecedented in the NOAA record that goes back to 1981. The image below shows the difference between all those years. The black line (2023) is as much as 0.3°C hotter than the orange line (2022), and we're only just entering the upcoming El Niño. 


Vast amounts of ocean heat are moving toward the Arctic this year. With further melting of sea ice and thawing of permafrost, the Arctic Ocean can be expected to receive more and more heat over the next few years, i.e. more heat from direct sunlight, more heat from rivers, more heat from heatwaves and more ocean heat from the Atlantic Ocean and the Pacific Ocean.

Last year, North Atlantic sea surface temperatures reached a record high of 24.9°C in early September. Rising temperatures threaten to trigger massive loss of sea ice (and loss of albedo) and eruptions of methane from the seafloor of the Arctic Ocean, as has been described many times before, such as in this post, in this post and in this post.

[ from earlier post ]

The above image illustrates the danger of two tipping points getting crossed, i.e. the Latent Heat Tipping Point and the Seafloor Methane Tipping Point.

Latent heat loss, feedback #14 on the Feedbacks page
[ see the Extinction page ]
This threatens to cause rapid destabilization of methane hydrates at the seafloor of the Arctic Ocean leading to explosive eruptions of methane, as its volume increases 160 to 180-fold when leaving the hydrates, as illustrated by the above image.

Conclusion

A huge temperature rise thus threatens to unfold over the next few years, as illustrated by the image on the right. Altogether, the rise from pre-industrial to 2026 could be more than 18.44°C by 2026.

Meanwhile, humans are likely to go extinct with a rise of 3°C and most life on Earth will disappear with a 5°C rise, as illustrated by the image below, from an analysis discussed in an earlier post. 

This situation calls for urgent action. Reducing emissions alone won't be enough. Carbon also needs to be removed from the atmosphere and oceans, through re-/afforestation, through pyrolysis of biowaste with the resulting biochar (and nutrients) returned to the soil and further methods. Even with a rapid transition to clean, renewable energy, with changes to food, land use, construction and waste management, and with removal of large amounts of carbon from the atmosphere and oceans, still more action is needed.


Marine Cloud Brightening is a good idea, while many further methods may first need more surplus clean energy to be available and/or require more R&D.

Whether action will happen successfully and rapidly enough is indeed a good question, but that question shouldn't be used as an excuse to delay such action, since taking such action simply is the right thing to do.

Accordingly, everyone is encouraged to support and share this Climate Emergency Declaration. 

[ image from Climate Emergency Declaration ]




Links

• NOAA - Monthly Northern Hemisphere Land Temperature Anomaly 
https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/global/time-series/nhem/land/all/3/1850-2023

• NOAA - Recent Daily Average Mauna Loa CO2

• NOAA - Weekly average CO2 at Mauna Loa
https://gml.noaa.gov/ccgg/trends/weekly.html

• Climate Reanalyzer - Daily sea surface temperatures
https://climatereanalyzer.org/clim/sst_daily

• Sea surface temperature at record high
https://arctic-news.blogspot.com/2023/03/sea-surface-temperature-at-record-high.html

• Dire situation gets even more dire

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

• NOAA - Climate Prediction Center - ENSO Discussion

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html


Posted by at
Labels: , , , , ,

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


Posted by at
Labels: , , , , , , , ,
Subscribe to: Posts (Atom)