Showing posts with label seafloor. Show all posts
Showing posts with label seafloor. Show all posts

Friday, February 2, 2024

Blue Ocean Event 2024?

How likely is an Arctic Blue Ocean Event (BOE) to occur in 2024 or even a Double BOE? The image below is alarming. 


The highest daily sea surface temperatures on record (going back to 1981) were reached in February 2024, even higher than the peaks in 2023. Even higher temperatures may be reached over soon, in March 2024 and April 2024.

As the above image shows, the highest temperatures for the year are typically reached in March. This was the case for the previous years on record, except for 2023 when the current El Niño started to emerge and when the highest peak for the year occurred in August. According to NOAA, the majority of models indicate that this El Niño will persist through March-May 2024. 

Antarctic sea ice extent typically reaches an annual minimum end February, while Arctic sea ice extent typically reaches an annual minimum in September, after a steep decline resulting from more sunlight reaching higher latitudes North and ocean heat reaching a second peak in August.   

Ominously, daily surface air temperatures in the Southern Hemisphere exceeded 17°C recently, something that never happened before in the record going back to 1981. Antarctic sea ice extent typically reaches an annual minimum end February. Loss of sea ice acts as a self-reinforcing feedback loop, accelerating the temperature rise. The daily surface air temperature in the Southern Hemisphere was 17.005°C on Feb 1, 2024, following a peak of 17.01°C on Jan 31, 2024.


Higher temperatures can cause sea ice to melt, even out of season

As illustrated by the image below, adapted from Pidwirny, sunlight does not reach the North Pole until the March Equinox. From that time on, insolation rises steeply. Around the June Solstice, more sunlight reaches the North Pole than anywhere else on Earth. In the image below, insolation is calculated taking into account the combined effects of angle of incidence and day length duration. 

The conclusion is that ocean heat is the main reason why melting of Arctic sea ice can occur early in the year. More specifically, the narrowing of the temperature difference between the Arctic and the Tropics can at times cause strong wind to be present along the path of the Gulf Stream. Rising ocean heat combined with strong wind can cause heat to move abruptly toward the Arctic Ocean, causing sea ice to fall in extent. 

Such an event is illustrated by the image below, adapted from NSIDC. The image shows a drop in sea ice extent at the end of January 2024 (blue), a time of year when Arctic sea ice is still expected to increase in extent and to keep increasing in extent for some time to come (grey). In this case, strong wind may have caused a huge amount of ocean heat that is present in the North Atlantic to move abruptly toward the Arctic Ocean, as discussed in an earlier post

For the time of year, Arctic sea ice extent is currently still extensive, compared to earlier years, which is a reflection of more water vapor in the atmosphere and more precipitation. While sea ice extent is relatively large, sea ice volume is among the lowest of all years on record for the time of year, as illustrated by the image below. 

This indicates that Arctic sea ice is very thin. Ominously, the image below indicates that there is a huge area near the North Pole with very thin sea ice. 


Furthermore, much of the thicker sea ice is located off the east coast of Greenland, which means that this sea ice is likely to melt away quickly as more sunlight starts reaching the Northern Hemisphere and temperatures rise in line with seasonal changes (see the insolation image further above).


The North Atlantic sea surface temperature was 20.4°C on February 15, 2024, i.e. 0.6°C higher than on February 15, 2023.

High North Atlantic sea surface temperatures spell bad news for the Arctic, as much ocean heat gets pushed toward the Arctic from the North Atlantic. 

North Atlantic sea surface temperatures are just starting to heat up from their annual minimum and can be expected to rise strongly, in line with seasonal changes. 

[ click on images to enlarge ]
Ominously, a peak temperature of 25.4°C was reached on Aug.31, 2023, much higher than the peak in any of the preceding years dating back to 1981.

During the six months between the September Equinox and the March Equinox (see image further above), no sunlight is reaching the North Pole. 

Nonetheless, temperature anomalies in the Arctic are already extremely high, due to ocean heat that has entered the Arctic Ocean from the North Atlantic, as illustrated by the two maps on the right and the two maps on the right further below.

Northern Hemisphere Sea Surface Temperature Anomalies were as much as 12.6°C or 22.7°F higher than 1981-2011 on February 15, 2024, locarion marked by the green circle on the image below.


Feedbacks 

Slowing down of AMOC and cooling due to heavier melting of Greenland's ice is causing less ocean heat to reach the Arctic Ocean, while a huge amount of ocean heat is accumulating in the North Atlantic, as it did in 2023. A large part of this heat in the North Atlantic can also be present underneath the sea surface.

These developments occur at the same time as ocean stratification increases (as temperatures rise, see above images), as more freshwater enters the ocean (as a result of more meltwater and of runoff from land and from rivers), and as more evaporation takes place and more rain falls further down the path of the Gulf Stream, all of which can contribute to formation and growth of a cold, freshwater lid at the surface of the North Atlantic.

cold freshwater lid on North Atlantic ]

Furthermore, storms can get stronger as temperatures rise and as changes take place to the Jet Stream. Strong wind can temporarily speed up currents that carry huge amounts of ocean heat with them toward the Arctic Ocean, as discussed in earlier posts such as this one. Much of the ocean heat in the North Atlantic can therefore be pushed abruptly underneath this freshwater lid and flow into the Arctic Ocean. The image below shows that the Jet Stream reached speeds as high as 455 km/h or 283 mph north of Washington on February 18, 2024 03:00 UTC, with Instantaneous Wind Power Density as high as 387.5 kW/m².


The image below shows wind speed at 250 hPa on a background of sea surface temperature anomalies versus 1981-2011. 


The danger is that, due to strong wind along the path of the Gulf Stream, huge amounts of ocean heat will abruptly get pushed into the Arctic Ocean, with the influx of ocean heat causing destabilization of hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane.

Changes to the Jet Stream and ocean heat accumulating in the North Atlantic Ocean are both consequences of the overall temperature rise. A distorted Jet Stream can cause an abrupt influx of ocean heat into the Arctic Ocean.

Such additional ocean heat, combined with a steep rise in insolation hitting the Arctic in April and May, may suffice to cause a Blue Ocean Event (BOE) to occur in 2024.

[ click on images to enlarge ]
The far North has the highest temperature anomalies, they can as high as 7.04°C, as the image on the right shows.

A BOE occurs when virtually all sea ice disappears and less than 1 million km² of sea ice remains. As the sea ice disappears, the surface color changes from white (sea ice) to blue (ocean) resulting in far more sunlight getting absorbed by the Arctic Ocean, instead of getting reflected back into space as was previously the case.

Albedo change constitutes a huge self-reinforcing feedback loop, i.e. the more sea ice disappears, the more sunlight gets absorbed by the Arctic Ocean, further accelerating sea ice melting. 

[ Albedo change, from the Albedo page ]

Next to the albedo loss, there is loss of the latent heat buffer constituted by the sea ice. Latent heat is energy associated with a phase change, such as the energy consumed when solid ice turns into water (i.e. melts). During a phase change, the temperature remains constant. Sea ice acts as a buffer that absorbs heat, while keeping the temperature at about zero degrees Celsius. As long as there is sea ice in the water, this sea ice will keep absorbing heat, so the temperature doesn't rise at the sea surface.

The amount of energy absorbed by melting ice is as much as it takes to heat up an equivalent mass of water from zero to 80°C. 

Without the buffer constituted by thicker sea ice, an influx of ocean heat could destabilize hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane.

[ click on images to enlarge ]
The above image illustrates these tipping points and Northern Hemisphere Ocean Temperature anomalies vs 1901-2000, created with NOAA data. Trends and tipping point estimates are added. The magenta trend is based on Jan.1880-Jan.2024 data and warns that the Seafloor Methane Tipping Point may be crossed in 2025. The red trend is based on Jan.2010-Jan.2024 data and better reflects variables such as El Niño, and it warns that the Seafloor Methane Tipping Point may be crossed in 2024. 


The above image, adapted from tropicaltidbits.com, shows a forecast for November 2024 of the 2-meter temperature anomaly in degrees Celsius, based on 1984-2009 model climatology. The anomalies are forecast to be very high for the Arctic Ocean.

Many additional feedbacks are active, such as changes to the Jet Stream and slowing down of AMOC, and they could speed up the crossing of such tipping points, as also discussed at the feedbacks page. The danger is that a cascade of events will unfold like a domino effect, leading to extinction of most species, including humans, as the image below warns. 

[ from earlier post - click on images to enlarge ]

Greenhouse gases rising

Meanwhile, concentrations of greenhouse gases keeps rising, as illustrated by the image below. 

The average daily carbon dioxide (CO₂) at Mauna Loa, Hawaii, was 426.21 ppm (parts per million) on February 4, 2024. The weekly average was 425.83 ppm. 

Critical is the rate of change, in particular the rapid rise in temperatures and greenhouse gas concentrations. To find higher CO₂ concentrations, one has to go back millions of years. 


A recent study concludes that: 
- A doubling of CO₂ is predicted to warm the planet a whopping 5°C to 8°C.
- The last time atmospheric CO₂ consistently reached today’s human-driven levels of 420 ppm was 14 million years ago.
- The hottest period was about 50 million years ago, when temperatures were as much as 12°C higher than today.

Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.



Links

• Blue Ocean Event
https://arctic-news.blogspot.com/p/blue-ocean-event.html

• Climate Reanalyzer - Daily Sea Surface Temperature, World (60°S-60°N)
https://climatereanalyzer.org/clim/sst_daily

• Pidwirny, M. "Earth-Sun Relationships and Insolation". Fundamentals of Physical Geography, 2nd Edition (2006)
http://www.physicalgeography.net/fundamentals/6i.html

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

• NSIDC - Arctic sea ice extent
https://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph

• Polar Portal - Sea Ice Thickness and Volume
http://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-thickness-and-volume

• University of Bremen - Arctic sea ice

• Scripps Institution of Oceanography at UC San Diego.

• Toward a Cenozoic history of atmospheric CO₂ - by The Cenozoic CO₂ Proxy Integration Project (CenCO₂PIP) Consortium






Sunday, January 14, 2024

Seafloor methane tipping point crossed in 2024?

The heat in December 2023 was felt most strongly in the Arctic, as illustrated by the NASA image below, showing anomalies above 1951-1980 as high as 9.9°C. 

The image below further illustrates heat striking the northern latitudes in 2023, showing that the temperature anomaly in 2023 was 2.19°C above 1880-1920 in between 24°North and the North Pole


The danger is that ocean heat could abruptly be pushed from the North Atlantic into the Arctic Ocean, temporarily raising temperatures at the seafloor of the Arctic Ocean, as discussed in earlier posts such as this one

Terrifying rise of Northern Hemisphere ocean temperature anomalies

The image shows the terrifying rise of Northern Hemisphere ocean temperature anomalies from 1901-2000, illustrating crossing of two tipping points, i.e. the Latent Heat Tipping Point and the Seafloor Methane Tipping Point.

This threatens to cause rapid destabilization of methane hydrates at the seafloor of the Arctic Ocean and lead to explosive eruptions of methane, as its volume increases 160 to 180-fold when leaving the hydrates. 


The image is an update of the image below, from a 2023 post and added here for reference purposes. Check out that post for more on the Latent Heat tipping Point and the Seafloor Methane Tipping Point.


Note that the above analyses are for annual data. An earlier analysis using monthly data shows that the seafloor methane tipping point was reached in August 2023. 

The danger is that, as the latent heat buffer disappears, incoming ocean heat can no longer be consumed by sea ice, but will instead heat up sediments at the seafloor of the Arctic ocean.

Latent heat loss, feedback #14 on the Feedbacks page
Ominously, sea surface temperatures (60°South-60°North) are on the rise in 2024, as illustrated by the image below.


The image below, adapted from NOAA, shows how high temperatures line up with El Niño months.

[ click on images to enlarge ]

Annual temperature anomalies as high as 2.5°C above pre-industrial

The temperature anomaly in 2023 may be as high as 2.5°C above pre-industrial, as illustrated by the image below.


For more on the analysis behind this potential rise of 2.5°C, see the pre-industrial page. Acknowledging the full strength of the rise is important, because of the feedbacks that come with it. Rising temperatures result in more water vapor getting in the atmosphere (7% more water vapor for every 1°C warming), further amplifying the temperature rise, since water vapor is a potent greenhouse gas. 

The IPCC likes people to believe that the temperature rise is only 1.1°C above pre-industrial, in which case there would be only 7.7% more water vapor in the atmosphere, but with a 2.5°C rise, there would be 17.5% more water vapor in the atmosphere. Those who seek to downplay the danger act as if changes to the Jet Stream and to ocean currents, Arctic sea ice, methane and water vapor can all be ignored.

Humans will likely go extinct with a 3°C rise. The image below shows annual mean global surface temperature (Land-Ocean) created with NASA Land-Ocean temperature anomaly versus 1902-1920, further adjusted by 0.99°C to reflect ocean air temperature, higher polar anomalies and an earlier (pre-industrial) base. The blue line shows a polynomial trend based on 1880-2023 data, indicating that a 3°C rise could eventuate by 2035. The magenta line shows a polynomial trend based on data from a shorter period (2010-2023), which better reflects short term variables such as El Niño and which indicates that a 3°C rise could eventuate as early as in 2024, i.e. this year. 


Note again that the above analyses are for annual data. An earlier analysis using monthly data 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). This 1.74°C anomaly can be adjusted by 0.99°C to reflect a pre-industrial base, air temperature and higher polar anomalies, adding up to a potential anomaly of 2.73°C.

Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at the Climate Emergency Declaration group.


Links

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

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

• 2024 looks to be worse than 2023
https://arctic-news.blogspot.com/2024/01/2024-looks-to-be-worse-than-2023.html

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

• NOAA - Northern Hemisphere ocean temperature anomalies vs 1991-2020
https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/global/time-series/nhem/ocean/12/12/1850-2023

• NOAA - Monthly temperature anomalies versus El Niño
https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202313/supplemental/page-2

• 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

• Cold freshwater lid on North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html

• Albedo, latent heat, insolation and more
https://arctic-news.blogspot.com/p/albedo.html

• Latent Heat
https://arctic-news.blogspot.com/p/latent-heat.html

• The Threat of Global Warming causing Near-Term Human Extinction
https://arctic-news.blogspot.com/p/threat.html

• Feedbacks
https://arctic-news.blogspot.com/p/feedbacks.html

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

• When Will We Die?

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

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

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

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




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