Showing posts with label Paul Beckwith. Show all posts
Showing posts with label Paul Beckwith. Show all posts

Friday, February 23, 2024

Stephen Salter, a giant in combating climate change passes away

   Stephen Salter (2012)
Stephen Hugh Salter, MBE, FRSE, Emeritus Professor of Engineering Design at the University of Edinburgh, was born December 7, 1938, and passed away peacefully on February 23, 2024, at the age of 85.

Stephen Salter was a giant who persisted to dedicate his life to combating climate change, and he did so in many ways until the very end. 

Stephen's work on wave energy led to Salter's Duck (1974), a device able to both generate energy and reduce wave strength. In 1977, Stephen built a multi-directional wave tank at the University of Edinburgh. 

In 2011, Stephen looked at ways to capture methane released in the Arctic, such as by covering lakes and parts of seas by sheets to collect the methane (drawing below).

Empty and filled extruded rubber trough cases with 4 times enlarged views of end and centre

Stephen was perhaps best known for his work on marine cloud brightening, i.e. deploying vessels to spray salt particles into the air in an effort to reduce sea surface temperatures, and thus also reducing sea ice loss and reducing the strength of extreme weather events including storms and hurricanes.

In the video below, Stephen discusses marine cloud brightening in a TEDx talk in 2016. 


Marine cloud brightening | Prof. Stephen Salter | TEDx Talks Published 15 Nov 2016

The image below is from the post Hurricane Moderation at Arctic-news.blogspot.com. 


In the video below, by theedinburghreporter, Stephen Salter talks about marine cloud brightening.


In the video below, Stephen Salter is interviewed by Nick Breeze (2022). 


Below is a screenshot from the above video by Nick Breeze. 

Stephen Salter discusses sending solar energy back out to space by means of Marine Cloud Brightening.
Screenshot by Sam Carana from video by Nick Breeze.

Stephen Salter (2022): "A jolly small change in reflectivity of the clouds will be sending solar energy back out to space enough to balance what the excess is that's being retained here by greenhouse gases (4:26-4:41). Maybe 10 cubic meters of water a second as sub micron drops sprayed in the right place would offset all the damage we've done since pre-industrial times (5:15-5:24)." 

Our hearts are saddened by this huge loss, and our thoughts are with Stephen's family and his many friends. Stephen's work will not be forgotten.

Added below is a video featuring Stephen Salter, Peter Wadhams, Paul Beckwith, Robert Tulip, Herb Simmens, Alaxandra Price and Win Rampen. 



Links

• Futuristic fleet of 'cloudseeders' - by John Latham (2007)
https://news.bbc.co.uk/2/hi/programmes/6354759.stm

• Sea-going hardware for the cloud albedo method of reversing global warming - by Stephen Salter, Graham Sortino and John Latham (2008)
https://royalsocietypublishing.org/doi/10.1098/rsta.2008.0136

• Can we capture methane from the Arctic seabed? (2011)

• Professor Stephen Salter receives top Academy Award (2012)

• Leading wave energy pioneer Prof Stephen Salter (2012) 
https://www.theengineer.co.uk/content/in-depth/leading-wave-energy-pioneer-prof-stephen-salter

• Coded modulation of computer climate models for the prediction of precipitation and other side-effects of marine cloud brightening (2013)

• Marine cloud brightening | Prof. Stephen Salter | TEDxHeriotWattUniversity |  TEDx talk (2016)
• Hurricane Moderation (2018)
https://arctic-news.blogspot.com/2018/09/hurricane-moderation.html

• Talking to Professor Stephen Salter - TheEdinburghReporter (May 23, 2019)

• Speaking with Professor Stephen Salter - The Edinburgh Report (June 1, 2019)

• Professor Stephen Salter at Holyrood speaking about project to arrest climate change

• John Latham obituary (2021)
https://www.theguardian.com/science/2021/may/30/john-latham-obituay

• Stephen Salter - Whole interview by Nick Breeze ClimateGenn (2022)



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Tuesday, December 5, 2023

Will temperatures keep rising fast?

[ discussed at facebook - click on images to enlarge ]

The above image, created with Climate Reanalyzer data, shows the temperature anomaly (in °C) compared to the 1979-2000 mean. In blue are the years 1979-2022 and in black and white is the year 2023 through December 3, 2023. A trend is added in pink and white, based on 2023 data. Note that the 1979-2000 mean isn't pre-industrial, the anomaly from pre-industrial is significantly higher.

[ click on images to enlarge ]
The trend warns that temperatures could keep rising rapidly over the next few months. A number of things can contribute to such a rapid rise:

  • The chance that the current El Niño will slow down over the next few months is minimal, as illustrated by the IRI image on the right.

  • Earth's radiation imbalance is very high, as illustrated by the NASA image below.


  • Antarctic sea ice extent is at record low for the time of year, as illustrated by the NSIDC image below, and the fall in extent is particularly steep in December. Sea ice loss results in less sunlight getting reflected back into space and instead getting absorbed by the ocean and the impact of Antarctic sea ice loss is even stronger than Arctic sea ice loss, as Antarctic sea ice is located closer to the Equator, as pointed out by Paul Beckwith in a video in an earlier post. A warmer Southern Ocean also comes with fewer bright clouds, further reducing albedo, as discussed here and here. For decades, there still were many lower clouds over the Southern Ocean, reflecting much sunlight back into space, but these lower clouds have been decreasing over time, further speeding up the amount of sunlight getting absorbed by the water of the Southern Ocean, and this 'pattern effect' could make a huge difference globally, as this study points out. Emissivity is a further factor; open oceans are less efficient than sea ice when it comes to emitting in the far-infrared region of the spectrum (feedback #23 on the feedbacks page).
  • There is a huge danger that ocean heat will reach and destabilize methane hydrates that are contained in sediments at the seafloor of oceans, resulting in massive methane eruptions, as discussed in many earlier posts such as this one.

  • Emissions are high and rising. On December 6, 2023, CO₂ was 420.16 ppm at Mauna Loa, Hawaii. Today’s greenhouse gas forcing of 4.6 W/m² is relative to mid-Holocene CO₂ of 260 ppm, i.e. the natural Holocene CO₂ level. Equilibrium global warming for today’s amount of greenhouse gases is 10°C, which is reduced to 8°C by today’s human-made aerosols. Warming in the past 6000 years was slowed down by aerosol cooling. Growing population, agriculture and land clearance produced aerosols and CO₂; wood was the main fuel for cooking and heating. Nonlinear aerosol forcing is largest in a pristine atmosphere. Impacts on people and nature will accelerate as global warming increases hydrologic (weather) extremes. The enormity of consequences demands a return to Holocene-level global temperature. (from: Global warming in the pipeline, by James Hansen et al.)
    Rises in methane can cause rapid warming. The image below, created with a Copernicus forecast for December 6, 2023 03 UTC, shows very high methane levels at higher latitudes north at 500 hPa.
  • [ image from a 2014 post ]
    Meanwhile, as emissions keep rising, politicians refuse to act, preferring to debate the size of the "carbon budget". Sadly, the IPCC lends credibility to the idea that there was a "budget" to be divided among polluters, a "budget" that would enable polluters to keep polluting for decades to come. This adds a false sense of accountability to this "budget", as if it was checked and verified by scientists across the world. Instead, there is just a huge carbon debt that has to be removed from the atmosphere and the oceans.

  • [ image from the Extinction page ]
    As more people become aware of the dire situation, widespread panic can set in, as warned about in this 2007 post. Instead of crossing a social tipping point that prompts people into action to combat the temperature rise, panic may set in that stops many people from showing up at work, resulting in a rapid loss of the aerosol masking effect, as industries that now co-emit cooling aerosols (such as sulfates) grind to a halt. People may start to collect and burn more wood, resulting in an increase in emissions that speed up the temperature rise. As temperatures rise, more fires could also break out in forests, peatlands and urban areas including landfills and waste dumps, further contributing to emissions that speed up the temperature rise. 
As said, the 1979-2000 base used in the image at the top is not pre-industrial. Anomalies would be much higher when using a genuinely pre-industrial base. The image on the right uses a 2.29°C 2020 anomaly from 3480 BC.

The image on the right shows many elements that could jointly cause a rapid temperature rise of more than 10°C, in the process causing the clouds tipping point to get crossed that on its own can push up the temperature rise by a further 8°C.

Much of this is described at the extinction page.

Conclusion

The precautionary principle calls for comprehensive and effective action to reduce the damage and to improve the situation as described in this 2022 post, in line with recognition of the climate emergency we're in.


Links

• Climate Reanalyzer
https://climatereanalyzer.org/clim/t2_daily/?dm_id=world

• Columbia Climate School, International Research Institute for Climate and Society

• NASA - Earth's Radiation Balance
https://svs.gsfc.nasa.gov/5173

• National Snow and Ice Data Center (NSIDC)
https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph

• Global warming in the pipeline, by James Hansen et al. 
https://academic.oup.com/oocc/article/3/1/kgad008/7335889

• Copernicus - Methane forecasts
https://atmosphere.copernicus.eu/charts/packages/cams/products/methane-forecasts

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

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

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

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

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

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


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Friday, October 13, 2023

Temperature rise - September 2023 and beyond

The above image, adapted from NASA and the image below, adapted from Climate Reanalyzer and using the same baseline, illustrate the September 2023 temperature anomaly.


September 2023 was the month with the highest temperature anomaly on record. What contributed to this?

El Niño
 

The temperature rose about 0.5°C from November 2022 to March 2023, and this occurred at a time when we were not even in an El Niño yet, as illustrated by the above image, from an earlier post. Below is an updated image, from January 1950 to September 2023, adapted from NOAA

[ click on images to enlarge ]
[ click on images to enlarge ]
The current El Niño is still strengthening, as illustrated by the image on the right, adapted from IRI.

Further contributors

There are further reasons why the temperature can be expected to keep rising beyond September 2023.

The number of sunspots has been higher than predicted and looks set to keep rising above predicted levels until July 2025, as discussed here.

The eruption of the submarine volcano near Tonga in January 2022 caused a lot of water vapor to reach high up into the atmosphere and this may still contribute to the temperature rise, as discussed here.

Aerosols that have a cooling effect, such as dust and sulfates (SO₄), are also important. As fossil fuel is burned, sulfates are co-emitted. Since they pollute the air, measures have been taken and are being taken to reduce them, e.g. in shipping, and this has pushed up the temperature rise. Meanwhile, cooling aerosols such as sulfates are still high. As illustrated by the image below, adapted from nullschool.net, SO₄ was as high as 8.621 τ at the green circle on October 6, 2023, at 07:00 UTC. In future, SO₄ could fall dramatically, e.g. in case of a sudden economic collapse, reducing the aerosol masking effect rapidly and abruptly causing a substantial rise in temperature.


After little change in the Antarctic sea ice extent graph for decades, extent loss was dramatic in 2022 and even more dramatic in 2023, as less and less sunlight was getting reflected back into space and instead was getting absorbed by the water of the Southern Ocean, as illustrated by the image below, adapted from NSIDC.
Sea ice retreat comes with loss of albedo, i.e. loss of the amount of sunlight reflected back into space, resulting in more heat getting absorbed in the Southern Ocean, making it a self-reinforcing feedback loop. Clouds constitute another self-reinforcing feedback loop; a warmer Southern Ocean comes with fewer bright clouds, further reducing albedo, as discussed here and here. For decades, there still were many lower clouds over the Southern Ocean, reflecting much sunlight back into space, but these lower clouds have been decreasing over time, further speeding up the amount of sunlight getting absorbed by the water of the Southern Ocean, and this 'pattern effect' could make a huge difference globally, as a recent study points out. Emissivity is a further factor; open oceans are less efficient than sea ice when it comes to emitting in the far-infrared region of the spectrum (feedback #23 on the feedbacks page). 



The above image was created by Zach Labe with NSIDC data (Arctic + Antarctic) for each year from 1979 to 2023 (satellite-era; NSIDC, DMSP SSM/I-SSMIS). The image illustrates that global sea ice extent  recently reached the largest anomaly in the satellite record. Anomalies are calculated using a 5-day running mean from a climatological baseline of 1981-2010. 2016 is shown with a yellow line. 2023 is shown using a red line (updated 10/16/2023).

In the video below, Paul Beckwith discusses the importance of loss of sea ice at around -60° (South).


As said, there are many factors behind the temperature increase around latitude -60° (South). As Paul mentions, this latitude receives a lot of sunlight around the year. Therefore, it is not surprising that, as oceans continue to heat up, there is huge loss of sea ice at this latitude, as well as loss of lower clouds, while open oceans are additionally less efficient than sea ice when it comes to emitting in the far-infrared region of the spectrum. The image below, adapted from NASA, shows a white band around -60° (South), indicating that the Southern Ocean has long been colder there than elsewhere, but has recently started to catch up with the global temperature rise.



The above image also illustrates that anomalies are highest in the Arctic, narrowing the temperature difference between the Arctic and the Tropics, with the air flow slowing down accordingly. 

[ image adapted from Copernicus ]
This in turn changes the Jet Stream and the Polar Vortex, resulting in blocking patterns that can, in combination with rising temperatures, strongly increase the frequency, intensity, duration and area coverage of extreme weather events such as storms and lightning, heatwaves and forest fires.

Forest fires in Canada have been releasing massive amounts of emissions that push up the temperature, including greenhouse gases such as carbon dioxide, warming aerosols such as black carbon & brown carbon and NMVOC (non-methane volatile organic carbon) and carbon monoxide that reduce the availability of hydroxyl, resulting in more methane and ozone in the atmosphere. 

[ NH sea surface temperature anomaly ]
At the same time, slowing down of the Atlantic Meridional Ocean Current (AMOC) can result in more ocean heat accumulating at the surface of the North Atlantic, as illustrated by the image on the right, from an earlier post.

As temperatures rise, increased meltwater runoff from Greenland and more icebergs moving south, in combination with stronger ocean stratification and stronger storms over the North Atlantic, can also cause a freshwater lid to form at the surface of North Atlantic that can at times enable a lot of hot water to get pushed abruptly underneath this lid toward the Arctic Ocean. The danger is that more heat will reach the seafloor and destabilize methane hydrates contained in sediments at the seafloor of the Arctic ocean. 

Ominously, very high methane levels continue to be recorded at Barrow, Alaska, as illustrated by the image below, adapted from NOAA.

The next few months will be critical as Arctic sea ice is sealing off the Arctic Ocean from the atmosphere, trapping heat underneath the ice and making it harder for ocean heat to get transferred from the Arctic Ocean to the atmosphere above the Arctic. Furthermore, sea ice is very thin, reducing the latent heat buffer that could otherwise have consumed ocean heat. 

The next danger is that the thin Arctic sea ice will rapidly retreat early next year as a warming Arctic Ocean will transfer more heat to the atmosphere over the Arctic, resulting in more rain and more clouds in the atmosphere over the Arctic, speeding up sea ice loss and further pushing up the temperature rise over the Arctic, as discussed at the feedbacks page, which also discusses how less Arctic sea ice can push up temperatures through the emissivity feedback. As temperatures rise over the Arctic, permafrost on land also threatens to thaw faster, threatening to cause huge releases of greenhouse gases, including carbon dioxide, methane and nitrous oxide. 


Meanwhile, emissions of greenhouse gases keep rising, further pushing up the temperature, as illustrated by the image below, from an earlier post.
  
[ Global energy-related greenhouse gas emissions 2000-2022, adapted from EIA ]
In the video below, Guy McPherson describes how temperature rise, loss of habitat and meltdown of nuclear power facilities each could result in rapid extinction of humans and many other species.


There are numerous further feedbacks that can accelerate the temperature rise and tipping points that can get crossed and cause even more abrupt rise of the temperature. One of these is the clouds tipping point that in itself can cause a temperature rise of 8°C, as discussed here.

Further feedbacks are also discussed at the Extinction page.  One further feedback is water vapor. A warmer atmosphere holds more water vapor, at a rate of 7% for each Degree Celsius the temperature rises. As temperatures keep rising, ever more water vapor will be sucked up by the atmosphere. This will also cause more droughts, reducing the ability of land to sustain vegetation and provide soil cooling through shading and through evaporation and formation of lower clouds, as discussed here. More water vapor in the atmosphere will also speed up the temperature rise because water vapor is a potent greenhouse gas.

The fact that such tipping points and feedbacks occur as greenhouse gas levels reach certain levels and as the temperature rise makes it critical to assess how fast greenhouse gas levels could rise and by how much the temperature has already risen. 

NASA data up through September 2023

The image below, adapted from NASA, shows that the September 2023 NASA Land+Ocean temperature was 1.78°C higher than it was in September 1923. The anomaly is 1.74°C when compared to a base centered around the year 1900 (1885-1915). The 1.74°C anomaly can be adjusted by 0.99°C to reflect a pre-industrial base, air temperature and higher polar anomalies (as shown in the box on the bottom right of the image), adding up to a potential anomaly of 2.73°C. 

[ click on images to enlarge ]
Indeed, earlier analysis such as discussed here, points out that the temperature may already have risen by more than 2°C (compared to pre-industrial) in 2015, when politicians pledged at the Paris Agreement to take action to combat the temperature rise to prevent this from happening. 

Blue: Polynomial trend based on Jan.1880-Sep.2023 data. 
Magenta: Polynomial trend based on Jan.2010-Sep.2023 data.
The above image is created with NASA Land+Ocean monthly mean global temperature anomalies vs 1885-1915, adjusted by 0.99°C to reflect ocean air temperature, higher polar anomalies and a pre-industrial base, and has trends added.  

Alarms bells have been sounding loud and clear for a long time, as discussed in posts such as this one, warning that the temperature could rise by more than 3°C by 2026. The above magenta graph shows how this could occur as early as next year (end 2024).

[ image from earlier post ]
[ image from the Extinction page ]
The above image illustrates the latent heat tipping point - estimated to correspond with a sea surface temperature anomaly of 1°C above the long term average (1901-1930 on the above image) - to get crossed and the seafloor methane tipping point - estimated to correspond with a sea surface temperature anomaly of 1.35°C - to get reached, as discussed in earlier posts such as this one, .

A Blue Ocean Event could occur as the latent heat and seafloor methane tipping points get crossed, and the ocean temperature keeps rising, as huge amounts of methane get released in the Arctic, as ever more heat keeps reaching and destabilizing methane hydrates contained in sediments at the seafloor of the Arctic Ocean, as discussed in many earlier posts such as this one.

Seafloor methane is one of many elements that could jointly cause a temperature rise of over 10°C, in the process causing the clouds tipping point to get crossed that can push up the temperature rise by a further 8°C, as illustrated by the image on the right, from the extinction page.

Conclusion

The precautionary principle should prevail and the looming dangers should prompt people into demanding comprehensive and effective action to reduce the damage and to improve the situation. 

To combat rising temperatures, a transformation of society should be undertaken, along the lines of this 2022 post in combination with a declaration of a climate emergency.


Links

• NASA - global maps

• NOAA - ENSO and Temperature bars

• The International Research Institute for Climate and Society, Columbia University Climate School
https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-sst_table

• Nullschool.net

• NSIDC - sea ice graph

• Zach Labe - Global sea ice - extent, concentration, etc.

• NASA - zonal means
https://data.giss.nasa.gov/gistemp/zonal_means

• Copernicus - Northern Hemisphere wildfires: A summer of extremes
https://atmosphere.copernicus.eu/northern-hemisphere-wildfires-summer-extremes

• NOAA - Barrow Atmospheric Baseline Observatory, United States
https://gml.noaa.gov/dv/iadv/graph.php?code=BRW&program=ccgg&type=ts

• Paul Beckwith - Accelerated Global Warming from Antarctic Sea Ice Collapse: Albedo, Latitude, Snow Cover on Ice…
https://www.youtube.com/watch?v=-5P1W4TrczQ

• Guy McPherson - College of Complexes Presentation (with Improved Audio) 

• NASA custom plots
https://data.giss.nasa.gov/gistemp/graphs_v4/customize.html

• Transforming Society



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Wednesday, August 9, 2023

Arctic sea ice August 2023

Arctic Ocean heating up

There are at least five mechanisms that cause the water of the Arctic Ocean to heat up, as described below. 

1. Direct Heat. Heat from sunlight directly reaches the surface, i.e. the sea ice or the water of the Arctic Ocean.

The August 8, 2023, image on the right, from Climate Reanalyzer, shows a 1-3 days forecast of maximum surface temperatures (2m). Heatwaves over land can extend over the Arctic Ocean. 

High levels of emissions and greenhouse gases over the Arctic increase the amount of heat that is reaching the water of the Arctic Ocean and the sea ice. 

The NASA satellite image below shows smoke from forest fires in Canada moving over the Beaufort Sea and over the sea ice on August 6, 2023. 
[ click on images to enlarge ]

A recent study highlights that forest fires can strongly contribute to the temperature rise. Smoke, soot and further aerosols settling on the sea ice also darken the surface, resulting in more sunlight getting absorbed (feedback #9 on the feedbacks page). 

The image on the right, from a Copernicus news release dated August 3, 2023, shows the dramatic growth in emissions from fires in Canada up to end July 2023. 

The news release quotes Copernicus Atmosphere Monitoring Service senior scientist, Mark Parrington, who comments: "As fire emissions from boreal regions typically peak at the end of July and early August, the total is still likely to continue rising for some more weeks."

The Climate Reanalyzer image below shows that the temperature in the Arctic was at a record high for the time of year of 5.64°C or 42.15°F on August 9, 2023. Earlier, a record temperature of 5.81°C or 42.46°F was reached (on July 27, 2023).

Arctic sea ice typically reaches its minimum extent half September, when temperatures in the Arctic fall below 0°C and water at the surface of the Arctic Ocean starts refreezing.


2. Heat from Rivers. Hot water from rivers ending in the Arctic Ocean is another way the water is heating up and this is melting the sea ice from the side.

The August 10, 2023, image below, from nullschool.net, illustrates the added impact of heat that is carried by rivers into the Arctic Ocean, with sea surface temperatures as high as 20.4°C or 68.7°F recorded at a location where the Mackenzie River flows into the Arctic Ocean (at the green circle, where the green arrow is pointing at).


On August 6, 2023, the sea surface was 14.5°C or 26.2°F hotter than in 1981-2011, at a nearby location where the Mackenzie River is flowing into the Arctic Ocean, as illustrated by the image below.


The image on the right shows that on August 10, 2023, the sea surface temperature was 17.6°C or 63.7°F at a location where the Lena River in Siberia enters the Arctic Ocean, i.e. 14.2°C or 25.5°F hotter than it was in 1981-2011 (at green circle).

The Lena River flows into the Laptev Sea which is mostly less than 50 meters deep, making it relatively easy for surface heat to reach the seafloor. 

The NOAA image underneath on the right shows sea surface temperatures in the Bering Strait as high as 19.2°C or 66.56°F on August 8, 2023.

The image illustrates that the water can heat up strongly where hot water from rivers and run-off from rainwater enters the Bering Strait.

3. Ocean Heat. Yet another mechanism is heat that is entering the Arctic Ocean from other oceans, i.e. from the North Atlantic Ocean and the Pacific Ocean. Sea ice underneath the sea surface is melting from below due to ocean heat. 

An earlier post discusses why we are currently facing record high sea surface temperatures in the North Atlantic.

The image below shows how the Gulf Stream is pushing ocean heat toward the Arctic Ocean, while sea surface temperatures show up as high as 33.1°C or 91.58°F on August 9, 2023. 


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

[ from earlier post ]

This ocean current contributes to the stronger and accelerating rise in temperature in the Arctic (compared to the rest of the world), which in turn causes deformation of the Jet Stream that can at times cause strong winds that speed up this ocean current, as discussed in earlier post such as this 2017 one. 

[ from earlier post ]

4. Sea ice moving out. The Arctic Ocean is also heating up as sea ice is getting pushed into the Atlantic Ocean. Even the thickest sea ice can break up into pieces and move along with the flow of meltwater from glaciers, ocean currents and/or strong wind.

[ Click on images to enlarge ]
The animation below, created with NASA Worldview satellite images, shows the northern tip of Greenland at the top left of each frame. The green square on the image on the right indicates the area of the animation. It's around Prinsesse Thyra Island in Northeast Greenland National Park. 

This is where typically the thickest sea ice is located. The animation shows the sea ice breaking up and moving out of the Arctic Ocean. What is left of the pieces will eventually melt in the Atlantic Ocean. Pieces of sea ice that are pushed out of the Arctic Ocean reduce the latent heat buffer, as they can no longer consume heat in the Arctic Ocean through melting.  


5. Sea ice sealing off the Arctic Ocean from the atmosphere

The sea ice used to reach its lowest extent approximately half September. With the change in seasons, air temperatures decrease and sea ice starts increasing in extent at the sea surface. The image below illustrates how, as the Arctic Ocean starts freezing over, less heat will from then on be able to escape to the atmosphere. Sealed off from the atmosphere by sea ice, greater mixing of heat in the water will occur down to the seafloor of the Arctic Ocean, as discussed in FAQ#21.

[ From the post September 2015 Sea Surface Warmest On Record ]

In October, sea ice has stopped melting and is increasing in extent at the surface of the Arctic Ocean. Also, as land around the Arctic Ocean freezes over, less fresh water will flow from rivers into the Arctic Ocean, while hot, salty water will continue to flow into the Arctic Ocean. As a result, the salt content of the Arctic Ocean increases, all the way down to the seafloor of the Arctic Ocean, increasing the danger that ice in cracks and passages in sediments at the seafloor will melt, allowing methane contained in the sediment to escape and enter the atmosphere.

[ Pingos and conduits. Hovland et al. (2006) ]
Warmer water reaching these sediments can penetrate them by traveling down cracks and fractures in the sediments, and reach the hydrates. The image on the right, from a study by Hovland et al., shows that hydrates can exist at the end of conduits in the sediment. Such conduits were formed when some of the methane did escape from such hydrates in the past. Heat can travel down such conduits relatively fast and reach methane hydrates that keep methane in cages of ice. As heat reaches the ice cages, a temperature rise less than 1°C can suffice to destabilize such cages, resulting in a huge abrupt eruption, as the methane expands more than 160 times in volume.

[ The Buffer has gone, feedback #14 on the Feedbacks page ]
Further increasing the danger, this return of the sea ice results in less moisture evaporationg from the water, which together with the change of seasons results in lower hydroxyl levels at the higher latitudes of the Northern Hemisphere, in turn resulting in less methane getting broken down in the atmosphere over the Arctic.

Feedbacks and further developments

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

In the video below, Peter Carter, Paul Beckwith and Dale Walkonen discuss the situation.


One such feedbacks is the formation and growth of a cold freshwater lid at the surface of the North Atlantic that enables large amounts of salty and relatively hot water to flow underneath this lid and underneath the remaining sea ice, to enter the Arctic Ocean, as discussed earlier here, as well as here and at the feedbacks page.


This further increases the danger of destabilization of methane hydrates contained in sediments at the seafloor of the Arctic Ocean. 

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

The situation is dire and the outlook is getting more grim every day, calling for a Climate Emergency Declaration and implementation of comprehensive and effective action, as described in the Climate Plan and as most recently discussed at Transforming Society.


Links

• Climate Reanalyzer - Outlook Forecast Maps

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

• Shortwave absorption by wildfire smoke dominated by dark brown carbon - by Rajan Chakrabarty et al.
https://www.nature.com/articles/s41561-023-01237-9
discussed at: https://www.facebook.com/groups/arcticnews/posts/10160935394954679

• Feedbacks

• Climate Reanalyzer - Daily 2-meter Air Temperature

• NOAA - Sea Surface Temperature (SST) Contour Charts

• NOAA - Global Monitoring Laboratory - Barrow, Alaska

• Feedbacks in the Arctic

• Record high North Atlantic sea surface temperature

• NASA Worldview

• Copernicus news release - 2023 Canada wildfires emissions have already doubled previous annual record (August 3, 2023)
https://atmosphere.copernicus.eu/2023-canada-wildfires-emissions-have-already-doubled-previous-annual-record

• Warning of mass extinction of species, including humans, within one decade

• Cold freshwater lid on North Atlantic





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