Showing posts with label heat. Show all posts
Showing posts with label heat. Show all posts

Friday, September 15, 2023

Seafloor methane tipping point reached

The bold black line at the top of the image below, adapted from Climate Reanalyzer, shows extremely high sea surface temperatures up to September 13, 2023, much higher than in any previous year on record.

The image below, created with NASA data, shows why these extremely high sea surface temperatures are so worrying. The image shows monthly mean global surface temperature anomalies (open ocean) vs 1901-1930. The ochre trend, based on January 1900-August 2023 data, indicates the latent heat tipping point was crossed in 2021 and the seafloor methane tipping point could be crossed in 2033. The red trend, based on August 2008-August 2023 data and better reflecting variables such as El Niño, indicates that the seafloor methane tipping point could be crossed late 2023. Data show the seafloor methane tipping point was reached in August 2023.

The latent heat tipping point is estimated to correspond with a sea surface temperature anomaly of 1°C above the long term average, 1901-1930 on the above image, as discussed in earlier posts such as this one.

Sea ice constitutes a latent heat buffer, consuming incoming heat as it melts. While the ice is melting, all energy (at 334 J/g) goes into changing ice into water and the temperature remains at 0°C (273.15K or 32 °F). Once all ice has turned into water, all subsequent energy goes into heating up the water, and will do so at 4.18 J/g for every 1°C the temperature of the water rises. 

Once Arctic sea ice has become very thin, ocean heat that was previously consumed by melting the sea ice, no longer gets consumed by melting of the sea ice, and further incoming heat instead gets absorbed by the Arctic Ocean, rapidly pushing up the temperature of the water of the Arctic Ocean. 

The latent heat tipping point has meanwhile been crossed. Loss of this buffer is linked to the seafloor methane tipping point, i.e. the point where additional heat reaches the seafloor and destabilizes hydrates contained in sediments at the seafloor. This tipping point comes with multiple self-reinforcing feedback loops, such as explosive growth in methane volume setting off further destabilization, rapid rise of Arctic temperatures, loss of permafrost and loss of albedo, and release of further greenhouse gases.

Crossing of the seafloor methane tipping point will occur later than crossing of the latent heat tipping point, i.e. the seafloor methane tipping point corresponds with a higher ocean temperature anomaly, estimated to correspond with a sea surface temperature anomaly of 1.35°C above the long term average.

The current situation is particularly precarious in the Arctic, as the North Atlantic Ocean is very hot and the Gulf Stream keeps pushing hot water toward the Arctic Ocean, while Arctic sea ice has become very thin and the latent heat tipping point has been crossed.

As the temperature of the Arctic Ocean keeps rising, more heat can reach sediments located at the seafloor, since much of the Arctic Ocean is very shallow and sediments at the seafloor of the Arctic Ocean can contain vast amounts of methane.

The danger is that additional heat will destabilize hydrates in these sediments, leading to explosive eruptions of methane, as its volume increases 160 to 180-fold when leaving the hydrates, and resulting in huge eruptions of methane both from the destabilizing hydrates and from methane that is present in the form of free gas underneath the hydrates.

[ from earlier post, click on images to enlarge ]

The above image, from an earlier post, illustrates that warnings have been given before about the danger of these two tipping points getting crossed in the Arctic. In the above image, the trends are based on annual sea surface temperature data for the Northern Hemisphere. The seafloor methane tipping point is estimated to correspond with ocean temperature anomalies reaching 1.35°C above the long term average.

The image below further illustrates the high sea surface temperatures in and around the Arctic Ocean, with the red to yellow colors indicating temperature anomalies above the 1981-2011 average, and the green circle marking a sea surface temperature anomaly near the North Pole of 0.4°C on September 13, 2023.  


The image below illustrates how incoming ocean heat that previously was consumed in the process of melting of the sea ice, is now causing the water of the Arctic Ocean to heat up, with more heat reaching the seafloor of the Arctic Ocean, which has seas that in many places are very shallow.

[ Latent heat loss, feedback #14 on the Feedbacks page ]
Further adding to the danger is that destabilization of methane hydrates can cause huge amounts of methane to erupt with great force from the seafloor in the form of plumes. Consequently, little of the methane can be broken down in the water by microbes, while there is very little hydroxyl in the atmosphere over the Arctic Ocean to break down the methane that enters the atmosphere.


[ click on images to enlarge ]
Ominously, very high methane levels continue to be recorded at Barrow, Alaska, as illustrated by the above NOAA image.

The MetOp satellite image on the right shows methane levels, with the magenta color indicating the highest methane levels recorded at surface level (1000 mb), on September 15, 2023 am.

The N20 satellite image underneath shows methane levels at an altitude corresponding with 487 mb on September 10, 2023 am. The magenta color again indicates the highest methane levels recorded at the time.

Note the high levels over the Beaufort Sea and elsewhere over the Arctic Ocean, as well as high levels recorded over oceans in the Southern Hemisphere.

Climate Emergency Declaration

A catastrophe of unimaginable proportions is unfolding. Life is disappearing from Earth and runaway heating could destroy all life on Earth. At 5°C heating, most life on Earth will have disappeared. When looking only at near-term human extinction, 3°C will likely suffice.

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

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

• NASA - GISS Surface Temperature Analysis

• Record high North Atlantic sea surface temperature




Sunday, September 10, 2023

Methane eruptions threaten


The above image, adapted from Climate Reanalyzer, shows that on September 8, 2023, the North Atlantic sea surface reached a new record high temperature, of 25.4°C, even higher than the record reached the day before.

The situation is critical! More heat entering the Arctic Ocean threatens to destabilize hydrates and cause huge amounts of methane to erupt and enter the atmosphere.

The image on the right, adapted from NASA Worldview, shows the poor state of the sea ice.

On September 8, 2023, the Polarstern reached the North Pole. The image below shows the research vessel and the sea ice at the North Pole.
 

The image on the right, adapted from University of Bremen, shows Arctic sea ice concentration and the route followed by the Polarstern. 

The threat is that, as the water of the Arctic Ocean keeps heating up, heat will reach the seafloor and destabilize methane hydrates contained in sediments at the seafloor, resulting in eruptions of huge amounts of methane. 

Erupting from the hydrates occurs at great force, since the methane expands 160 when decompressed, resulting in the methane rapidly rising in the form of plumes, leaving little or no opportunity for microbes to decompose the methane in the water column. Furthermore, the atmosphere over the Arctic contains very little hydroxyl, resulting in methane persisting in the air over the Arctic much longer than elsewhere. 

After months of very high temperatures, the Arctic reached a new record high temperature for the time of year, i.e. 1.52°C on September 10, 2023, an anomaly of 2.25°C.


Meanwhile, global sea ice extent is much lower than in any other year on record for this time of year.


Ominously, very high methane levels continue to be recorded at Barrow, Alaska, U.S. 

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

• Climate Reanalyzer - North Atlantic sea surface temperature

• NASA Worldview

• Polarstern reaches North Pole - Research icebreaker at the northernmost point of the earth for the seventh time

• University of Bremen - Arctic sea ice concentration

• Arctic Data archive System

• NOAA - Barrow Atmospheric Baseline Observatory, United States

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


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





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


Wednesday, April 27, 2022

Carbon dioxide crosses 422 ppm

Carbon dioxide (CO₂) reached an average daily concentration of 422.06 ppm on April 26, 2022, at Mauna Loa, Hawaii.


Furthermore, very high methane (CH₄) concentrations were recorded recently at Mauna Loa, Hawaii, with surface flask readings appearing to be as high as 1955 ppb.  


Clouds tipping point

A methane concentration of 1955 ppb corresponds, at a Global Warming Potential (GWP) of 200, with a carbon dioxide equivalent (CO₂e) of 391 ppm. Together with the above daily average CO₂ concentration of 422.06 ppm this adds up to a joint CO₂e of 813.06 ppm, i.e. less than 387 ppm away from the clouds tipping point (at 1200 ppm CO₂e) that on its own could raise the global temperature by 8°C.

Such a 387 ppm CO₂e could be added almost immediately by a burst of seafloor methane less than the size of the methane that is currently in the atmosphere (about 5 Gt). There is plenty of potential for such an abrupt release, given the rising ocean heat and the vast amounts of methane present in vulnerable sediments at the seafloor of the Arctic Ocean, as discussed in posts such as this one.


The 1200 ppm CO₂e clouds tipping point could also be crossed even without such an abrupt seafloor methane release. Carbon dioxide and methane levels are rising rapidly. The above image shows carbon dioxide concentration with a trend added, based on NOAA 1980-2021 mean global annual carbon dioxide data, illustrating how carbon dioxide concentration could cross 750 ppm by the end of the year 2029.

[ see also the importance of methane ]

The above image shows methane concentration with a trend added, based on NOAA 2008-2021 mean global annual methane data, illustrating how methane concentration could cross 4100 ppb by the end of the year 2029 and how methane's impact could cross 820 ppm CO₂e by the end of the year 2029.

As illustrated by the image below, 750 ppm carbon dioxide and 820 ppm CO₂e methane would together yield a joint CO₂e of 1570 ppm and thus would have already raised the global temperature by 8°C due to the clouds feedback much earlier than 2029, while the temperature rise would also have been driven up by the higher carbon dioxide and the methane concentrations. 


Furthermore, nitrous oxide is also rising and there are many further forcers, as discussed at the Extinction page. Altogether, there is the potential for a temperature rise of well over 18°C by 2026, as discussed in an earlier post.

Such high carbon dioxide concentrations could occur due to forest fires causing soils to burn (especially peat soils), which can also add vast amounts of methane to the atmosphere. 

The IPCC does contemplate high carbon dioxide scenarios (see image right), but as discussed in an earlier post, does not mention the clouds tipping point.

High carbon dioxide scenarios typically stop at the year 2100 and rarely do concentrations reach higher than 1200 ppm.

In the image on the right, from a 2020 analysis by Malte Meinshausen et al., the SSP5-8.5 scenario is extended to the year 2300 and a carbon dioxide concentration of well over 2100 ppm is reached around 2240.

In conclusion, there is plenty of scientific consideration of the potential for high concentrations of carbon dioxide and methane to eventuate, but it is typically ignored or waved away as too distant in the future to worry about. 

In other words, what's lacking is analysis of abrupt catastrophic climate change.

Climate change danger assessment

The image below expands risk assessment beyond its typical definition as the product of the severity of impact and probability, by adding a third dimension: timescale.


Water in soil and atmosphere

The image on the right, from a news release associated with a recent study, shows changes in atmospheric thirst, measured in terms of reference evapotranspiration from 1980-202 (in mm).

As temperatures rise due to people's emissions, more evaporation will take place over both land oceans, but not all water will return as precipitation, so more water vapor will stay in the air.

[ click on images to enlarge ]
The water-holding capacity of the atmosphere increases by about 7% for every 1°C (1.8°F) rise in temperature, in line with the Clausius–Clapeyron relation

In many cases, this means drier soils and vegetation, making vegetation more vulnerable to pests and diseases, and more prone to fire hazards. 

Water in the soil acts as a buffer, slowing down the temperature rise, so drier soil will heat up faster and further, causing land surface temperatures to rise even more and amplifying the impact of Urban heat island and Heat dome phenomena.

The image on the right, adapted from ESA, shows land surface temperatures as high as 65°C (149°F) in India on April 26, 2022. Note that land surface temperatures can be substantially higher than air temperatures. 

As temperatures rise, extreme weather events increase in frequency and intensity. The duration of extreme weather events can also increase, due to blocked weather patterns resulting from changes to the Jet Stream.

This contributes to shortages in food and water supplies. As long as glaciers are melting in the mountains, rivers will keep supplying some water, but the snow and ice cover is disappearing rapidly around the globe. 

The image on the right shows that food prices have risen strongly over the past few years and extreme weather events resulting from the global temperature rise have strongly contributed to the price rise. 

Further contributing to this rise is the rising demand for fertilizers that are currently all too often produced with fossil fuel, as political will to produce food in better ways remains lacking. 

Heat stress

Another issue is humidity. The more water vapor there is in the air, the harder temperature peaks are to bear.

The human body can cool itself by sweating, which has a physiological limit that is often described as a 35°C wet-bulb temperature

A 2020 study (by Raymond et al.) warned that this limit could be regularly exceeded with a temperature rise of less than 2.5°C (compared to pre-industrial).

Meanwhile, recent research found that in practice the limit will typically be lower and depending on circumstances could be as low as a wet-bulb temperature of 25°C.

In the video below, Paul Beckwith discusses the danger of combined high heat and humidity. 


In the video below, Guy McPherson also discusses the danger of combined high heat and humidity. 


Extinction

A 2018 study (by Strona & Bradshaw) indicates that most life on Earth will disappear with a 5°C rise. Humans, who depend for their survival on many other species, will likely go extinct with a 3°C rise, as illustrated by the image below, from an earlier post.


Conclusion

This further highlights the imminence of the danger and adds further urgency to the call for immediate, comprehensive and effective action, as described in the Climate Plan.


Links

• NOAA - Global Monitoring Laboratory, Recent Daily Average CO₂ at Mauna Loa, Hawaii, U.S. 
• NOAA - Global Monitoring Laboratory, Methane (surface flasks) at Mauna Loa, Hawaii, U.S. 
• The Importance of Methane
https://arctic-news.blogspot.com/p/the-importance-of-methane-in-climate.html

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

• NOAA - Globally averaged marine surface annual mean carbon dioxide data
https://gml.noaa.gov/webdata/ccgg/trends/co2/co2_annmean_gl.txt

• NOAA - Globally averaged marine surface annual mean methane data
https://gml.noaa.gov/webdata/ccgg/trends/ch4/ch4_annmean_gl.txt

• NOAA - Mauna Loa CO2 weekly mean and historical comparisons
https://gml.noaa.gov/webdata/ccgg/trends/co2/co2_weekly_mlo.txt

• Methane rise is accelerating

• Runaway temperature rise by 2026?
• Extinction
https://arctic-news.blogspot.com/p/extinction.html

• Shortcomings of IPCC AR6 WGIII - Mitigation of Climate Change
https://arctic-news.blogspot.com/2022/04/shortcomings-of-ipcc-ar6-wgiii-mitigation-of-climate-change.html

• NOAA Mauna Loa CO₂ annual mean data
https://gml.noaa.gov/ccgg/trends/data.html

• NOAA globaly averaged marine surface annual mean methane data
https://gml.noaa.gov/ccgg/trends_ch4

• Is the IPCC creating false perceptions, again?
https://arctic-news.blogspot.com/2021/08/is-the-ipcc-creating-false-perceptions-again.html

• The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500 - by Malte Meinshausen et al. 
https://gmd.copernicus.org/articles/13/3571/2020

• Clausius–Clapeyron relation

• Heat dome
https://en.wikipedia.org/wiki/Heat_dome

• ESA - Heatwave across India
https://www.esa.int/ESA_Multimedia/Images/2022/04/Heatwave_across_India

• Evaporative Demand Increase Across Lower 48 Means Less Water Supplies, Drier Vegetation, and Higher Fire Risk
https://www.drought.gov/news/evaporative-demand-increase-across-lower-48-means-less-water-supplies

• A Multidataset Assessment of Climatic Drivers and Uncertainties of Recent Trends in Evaporative Demand across the Continental United States - by Christine Albano et al.
https://journals.ametsoc.org/view/journals/hydr/23/4/JHM-D-21-0163.1.xml

• It could be unbearably hot in many places within a few years time
https://arctic-news.blogspot.com/2016/07/it-could-be-unbearably-hot-in-many-places-within-a-few-years-time.html

• The emergence of heat and humidity too severe for human tolerance - by Colin Raymond et al.
https://www.science.org/doi/10.1126/sciadv.aaw1838

• Evaluating the 35°C wet-bulb temperature adaptability threshold for young, healthy subjects (PSU HEAT Project) - by Daniel Vecellio et al.
https://pennstate.pure.elsevier.com/en/publications/evaluating-the-35c-wet-bulb-temperature-adaptability-threshold-fo

• Co-extinctions annihilate planetary life during extreme environmental change, by Giovanni Strona and Corey Bradshaw (2018)
https://www.nature.com/articles/s41598-018-35068-1

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

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

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