Wednesday, July 24, 2024

High Wet Bulb Globe Temperature Danger

Wet Bulb Globe Temperature (WBGT) takes into account the effect of temperature, RH (relative humidity), wind speed, and solar radiation. WBGT is used by weather.gov to warn about extreme heat stress when in direct sunlight, as is forecast to occur in grey areas on July 26, 2024 at 21 UTC. 

[ click on images to enlarge ]

The inset shows that a temperature of 113°F or 45°C and a Wet Bulb Globe Temperature of 95°F or 35°C is forecast for a location 8 miles south of Parker, Arizona, on July 26, 2024 at 21 UTC. 

The above map illustrates that extreme heat stress can occur at higher latitudes, e.g. the grey areas in the north of the United States that extend into Canada. The danger occurs where high temperatures coincide with high relative humidity. 

The image below further illustrates the danger. It shows that a 'feel like' temperature of 54°C (129.1°F) and a wet bulb temperature of 31°C (87.7°F) hit an area west of Wuhan, China, on July 23, 2024 at 10:00 UTC (green circle). 

The temperature at that location in China wasn't the highest on the map, it was 36.4°C (97.4°F), which is high, but what further contributed to make conditions hard to bear was that relative humidity was 68%.

The image on the right, adapted from Climate Reanalyzer, shows a 3-day forecast of temperatures in the region, run on July 23, 2024. 

Heat stress is the leading cause of weather-related deaths in the United States, as illustrated by the image below (credit: NOAA). 


As the above image notes, the values for heat fatalities may be conservative. Research finds that where heat is being listed as an official cause of death, this likely underestimates the full toll of these events. Extreme heat can trigger heart attacks and strokes. In addition, some heart disease risk factors, such as diabetes—as well as heart medications, such as diuretics and beta blockers—can affect a person’s ability to regulate their body temperature and make it difficult to handle extreme heat. The study finds that extreme heat accounted for about 600-700 additional deaths from cardiovascular disease annually. A study estimates that extreme heat accounted for 12,000 premature deaths in the contiguous U.S. from 2000 to 2010, and an analysis calculates that the summer 2022 heatwave killed 61,000 people in Europe alone.

As temperatures and humidity levels keep rising, a tipping point can be reached where the wind factor no longer matters, in the sense that wind can no longer provide cooling. The human body can cool itself by sweating, which has a physiological limit that was long described as a 35°C wet-bulb temperature. Once the wet-bulb temperature reaches 35°C, one can no longer lose heat by perspiration, even in strong wind, but instead one will start gaining heat from the air beyond a wet-bulb temperature of 35°C.

Accordingly, a 35°C wet-bulb temperature (equal to 95°F at 100% humidity or 115°F at 50% humidity) was long seen as the theoretical limit, the maximum a human could endure.

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


A 2022 study (by Vecellio et al.) finds that the actual limit is lower — about 31°C wet-bulb or 87°F at 100% humidity — even for young, healthy subjects. The temperature for older populations, who are more vulnerable to heat, is likely even lower. In practice the limit will typically be lower and depending on circumstances could be as low as a wet-bulb temperature of 25°C.

Climate change danger assessment

The image below, earlier discussed here, expands risk assessment beyond its typical definition as the product of the severity of impact and probability of occurrence, by adding a third dimension: timescale, in particular imminence.



Imminence alone could make that the danger constituted by rising temperatures needs to be acted upon immediately, comprehensively and effectively. While questions may remain regarding probability, severity and timescale of the dangers associated with climate change, the precautionary principle should prevail and this should prompt for action, i.e. comprehensive and effective action to reduce damage and improve the situation is imperative and must be taken as soon as possible.

Rapidly rising temperatures constitute tipping points in several ways

Firstly, there is a biological threshold beyond which rising temperatures become lethal for humans, as discussed above.

Secondly, as Gerardo Ceballos describes in the video below and in a 2017 analysis, there is a biological tipping point that threatens annihilation of species via the ongoing sixth mass extinction. Researchers such as Gerardo Ceballos (2020), Kevin Burke (2018) and Ignation Quintero (2013) have for years warned that mammals and vertebrates cannot keep up with the rapid rise in temperature. Humans are classified as vertebrate mammals, indicating that we will not avoid the fate of extinction, Guy McPherson (2020) adds.

Thirdly, there are further tipping points, e.g. social-political ones. On the one hand, it would be good if people became more aware, as this could prompt more people into supporting the necessary action. On the other hand, as temperatures keep rising, there is also a danger that panic will break out, dictators will grab power and civilization as we know it will collapse abruptly, as warned about earlier, e.g. in 2007.

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

• Wet Bulb Globe Temperature
https://digital.mdl.nws.noaa.gov

• National Weather Service - Wet Bulb Globe Temperature: How and when to use it
https://www.weather.gov/news/211009-WBGT

• The emergence of heat and humidity too severe for human tolerance - by Colin Raymons et al. (2020)
https://www.science.org/doi/10.1126/sciadv.aaw1838

• Brief periods of dangerous humid heat arrive decades early
https://www.climate.gov/news-features/featured-images/brief-periods-dangerous-humid-heat-arrive-decades-early

• Evaluating the 35°C wet-bulb temperature adaptability threshold for young, healthy subjects (PSU HEAT Project) - by Daniel Vecellio et al. (2022)
https://journals.physiology.org/doi/full/10.1152/japplphysiol.00738.2021
Discussed at facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10159973158374679

• NOAA - Weather Fatalities 2022
https://www.weather.gov/hazstat

• The Effects of Heat Exposure on Human Mortality Throughout the United States - by Drew Shindell (2021)
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GH000234

• Heat-related mortality in Europe during the summer of 2022 - by Joan Ballester et al.
https://www.nature.com/articles/s41591-023-02419-z
Discussed at facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10160875637104679

• As Temperatures Spike, So Do Deaths from Heart Disease (2022 News release)
https://www.acc.org/About-ACC/Press-Releases/2022/03/22/20/06/As-Temperatures-Spike-So-Do-Deaths-from-Heart-Disease

• Association of Extreme Heat and Cardiovascular Mortality in the United States: A County-Level Longitudinal Analysis From 2008 to 2017 - by Sameed Khatana et al. (2022)
https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.122.060746

• 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
Discussed at facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10156903792219679

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

• Climate Reanalyzer - Hourly Forecast Maps
https://climatereanalyzer.org/wx/fcst/?mdl_id=nam&dm_id=conus-lc&wm_id=t2

• PBS video - Too HOT and HUMID to Live: Extreme Wet Bulb Events are on the Rise
https://www.pbs.org/video/too-hot-and-humid-to-live-extreme-wet-bulb-events-are-on-th-fazocs

• Nullschool
https://earth.nullschool.net

• How agriculture hastens species extinction | 60 Minutes (CBS News) | Gerardo Ceballos
https://www.youtube.com/watch?app=desktop&v=f21WWocqR-c

• Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines - by Gerardo Ceballos, Paul R. Ehrlich and Rodolfo Dirzo (2017)
https://www.pnas.org/content/114/30/E6089

• Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction - by Gerardo Ceballos, Paul Ehrlich, and Peter Raven (2020)
https://www.pnas.org/content/early/2020/05/27/1922686117
Discussed at facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10158460232764679

• Rates of projected climate change dramatically exceed past rates of climatic niche evolution among vertebrate species - by Ignatio Quintero et al. (2013)
https://onlinelibrary.wiley.com/doi/abs/10.1111/ele.12144

• Pliocene and Eocene provide best analogs for near-future climates - by Kevin Burke et al. (2018)
https://www.pnas.org/doi/10.1073/pnas.1809600115
Discussed at facebook at: 


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Saturday, July 13, 2024

Both Paris Agreement thresholds clearly crossed

Temperatures are rising

The NASA temperature anomaly vs. 1904-1924 shows that the temperature has been above 1.5°C for the past twelve months, as illustrated by the image below. The red line shows the trend (one-year Lowess Smoothing) associated with the rapid recent rise.


Note that the 1904-1924 base is not pre-industrial. When using a genuinely pre-industrial base, the temperature anomaly has over the past twelve months also been above the 2°C threshold that politicians at the 2015 Paris Agreement pledged wouldn't be crossed.

[ from earlier post ]
The above image, from an earlier post, shows that the February 2024 temperature was 1.76°C above 1885-1915, potentially 2.75°C above pre-industrial (bright yellow inset right). The image was created by Sam Carana for Arctic-news.blogspot.com with an April 2024 data.giss.nasa.gov screenshot. The red line (6 months Lowess smoothing) highlights the steep rise that had already taken place by then.

On July 21, 2024, the global temperature reached 17.09°C (62.76°F), a new record high. The previous record, 17.08°C, was reached on July 6, 2023.

The next day, on July 22, 2024, the global temperature reached 17.15°C (62.87°F), a new record high.


The image below shows that the sea surface temperature (60°S-60°N) was 20.9°C (69.62°F) on July 19, 2024, up from 20.82°C (69.48°F) on July 3, 2024. The question is whether the August 2024 sea surface temperatures will be higher than the peak reached in 2023.

The temperature at the North Pole was 0.1°C (32.3°F) on July 21, 2024, and is forecast to rise over the next few days.


Feedbacks

Higher temperatures come with feedbacks, as illustrated by the image below, from an earlier post.


As sea ice disappears, feedbacks accelerate the loss, e.g.:
• Albedo feedback #1 (water is less reflective than ice)
• Emissivity feedback #23 (water is less efficient than ice in emitting in the far-infrared region of the spectrum)
• Water vapor and clouds feedback #25 (warmer water comes more water vapor and less low-level clouds that reflect sunlight back into space).

[ click on images to enlarge ]
Furthermore, decline of sea ice and permafrost is forecast to result in huge emissions of carbon dioxide, nitrous oxide and methane, including seafloor methane (feedback #16).

Permafrost decline also results in more meltwater in rivers. Heatwaves further heat up the water in rivers flowing into the Arctic Ocean. The image on the right shows sea surface temperatures as high as 20.2°C (68.36°F) in the Bering Strait on July 25, 2024.

Deformation of the Jet Stream occurs as the Arctic heats up more rapidly than the rest of the world, which narrows the temperature difference between the Tropics and the Arctic, and this in turn changes the shape of the Jet Stream (feedback #19).

The Jet Stream will meander more and can at times even form circular wind patterns in some areas, which can strongly amplify extreme weather events such as storms that come with flooding and heatwaves, increasing their intensity, frequency, duration and area covered.

On land, more extreme weather can cause strong rainfall, causing even stronger thawing of permafrost and more run-off of water into the Arctic Ocean (feedback #24). Storms and heatwaves further accelerate heating up of river water, causing a lot more heat to enter the Arctic Ocean (feedback #4).

[ click on images to enlarge ]
Additionally, deformation of the Jet Stream can at times speed up the flow of ocean heat toward the Arctic Ocean. Deformation of the Jet Stream enables strong winds to develop over the North Atlantic, which can in turn strongly accelerate the speed at which hot water is flowing toward the Arctic Ocean along path of the Gulf Stream. As a deformed Jet Stream speeds up this flow, huge amounts of ocean heat can abruptly be pushed from the North Atlantic into the Arctic Ocean in the path of the Gulf Stream.

The image on the right shows hot water getting pushed along the path of the Gulf Stream from the Gulf of Mexico toward the Arctic Ocean. The image shows sea surface temperatures as high as 32.9°C (91.22°F) on July 15, 2024.

Furthermore, a freshwater lid can form on top of the surface of the North Atlantic, enabling more hot water to flow underneath this lid into the Arctic Ocean (feedback #28). 


Biochar needed to fight forest fires

Higher temperatures also come with greater forest fires hazards (feedback #9). Stronger drought and heatwaves and increased lightning further increase forest fire hazards. Forest fires result in emissions that cause black carbon to settle on ice, accelerating the temperature rise due to albedo loss and speeding up thawing of permafrost and melting of sea ice. The image below, adapted from Copernicus, shows a biomass burning aerosols forecast for July 22, 2024.


Forest fires contribute to the temperature rise in multiple ways, including:
• forest fires cause emissions that cause more heat to be trapped; 
• forest fires contributed to the 2023 global net land carbon dioxide sink to be the weakest since 2003; 
• forest fires reduce soil moisture content, which in turn reduces health and growth of vegetation and makes the land more vulnerable to erosion; 
• forest fires cause emissions of black carbon that darkens the surface, resulting in less sunlight getting reflected back into space.

The study into the carbon sources and sinks refers to itself as an "analysis of the global carbon budget", which can give the wrong impression that it was healthy and sustainable to cause carbon emissions as long as emissions were "compensated" by carbon taken up by land and ocean "sinks". Similarly, the IPCC refers to a "carbon budget" as if there was an amount of carbon to be divided among polluters and to be consumed for decades to come. Instead, action is needed to reduce concentrations of carbon both in oceans and in the atmosphere. On land, the soil carbon content needs to increase, which can be achieved by methods such as pyrolysis of biowaste and adding the resulting biochar to the soil, which will reduce fire hazards, sequester carbon and support the presence of moisture & nutrients in the soil and the health & growth of vegetation, as discussed at the Climate Plan group and the biochar group.

For more on feedbacks, see the feedbacks page.

Sea surface temperatures in the Northern Hemisphere

After an astonishing rise in 2023, sea surface temperature anomalies fell for six months in the Northern Hemisphere, but they are rising again, threatening to cause dramatic sea ice loss over the next few months and destabilize sediments at the seafloor, resulting in huge amounts of methane erupting and abruptly entering the atmosphere.


Rising sea surface temperatures are a major driver of sea ice loss.

Global sea ice extent takes a tumble

Higher temperatures result in more loss of sea ice. The image below shows that the global sea ice extent remained at a record low for the time of year on July 25, 2024, after a huge fall from 22.45 million km² on July 9, 2024, to 21.15 million km² on July 25, 2024.


Global sea ice extent is at record low for the time of year, as feedbacks kick in with greater ferocity, such as albedo loss, latent heat buffer loss, emissivity loss, more water vapor, less lower clouds, Jet Stream changes, more emissions, lightning and forest fires, all contributing to accelerate sea ice loss and the temperature rise.

Arctic sea ice

The image below, adapted from the Danish Metereological Institute, indicates that Arctic sea ice volume is at a record low for the time of year, as it has been for most of the year. At the same time, Arctic sea ice extent is not the lowest on record for the time of year; on July 25, 2024, Arctic sea ice extent was third lowest on record, extent was lower only in 2019 and 2020 of all years on record. See discussion at facebook. The implication is that sea ice must be very thin.


The image below, adapted from the University of Bremen, shows Arctic sea ice thickness on July 19, 2024. 

The above images shows that most of the thicker Arctic sea ice has melted, i.e. the latent heat buffer has virtually disappeared. This and further feedbacks and events (e.g. high sunspots) may cause temperatures to keep rising, even while La Niña is expected to prevail in Aug-Oct 2024. The screenshot below, from an earlier post, further illustrates the danger.


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

• NASA - datasets and images
https://data.giss.nasa.gov

• Copernicus - Climate Pulse


• Copernicus - aerosol forecasts

• Low latency carbon budget analysis reveals a large decline of the land carbon sink in 2023 - by Piyu Ke et al. 
https://arxiv.org/abs/2407.12447
• Arctic Data archive System - National Institute of Polar Research - Japan
https://ads.nipr.ac.jp/vishop

• NOAA - Office of Satellite and Product Operations (OSPO)
• NOAA - National Centers for Environmental Information - Climate at a Glance - Global Time Series
https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/global/time-series/nhem/ocean/1/0/1850-2024

• Feedbacks

• Danish Meteorological Institute - Arctic sea ice volume and thickness 
https://ocean.dmi.dk/arctic/icethickness/thk.uk.php

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

• Sunspots
https://arctic-news.blogspot.com/p/sunspots.html

• NOAA - Climate Prediction Center - ENSO: Recent Evolution, Current Status and Predictions 
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Thursday, July 11, 2024

The predicament of climate scientists on the road to a super tropical Earth

 by Andrew Glikson

As temperatures in large parts of the Earth are soaring (cf. 52.3°C in Delhi, flames engulf large regions in California, tornadoes ravage the Gulf of Mexico states, severe drought starve populations in southern Africa and climate extremes continue to taking over large parts of the Earth. Much like oncologists advising patients and their families of a terminal illness, so do climate scientists agonizing while reporting the advent of dangerous warming as temperatures rise and tipping points are broken. But while climate change has become more than evident, there is a heavy price to be paid by those who try to alert the public.
Figure 2. Global temperature relative to 1880-1920 based on the GISS analysis (Hansen et al., 2024).

One of the glaring misconceptions, which ignores the dispersal of greenhouse gases throughout the atmosphere, is as if their global effects depend on the country from which the carbon is extracted. Further, politically originated stigmas labels scientists as some kind of “alarmists” or “Cassandras”. A threat of institutional penalties affects scientist’s jobs. Along with the dominion of vested pro-carbon interests these factors drive humanity blind toward the Sixth Mass Extinction of Species.


In private conversations, many climate scientists express far greater concern at the progression and consequences of global warming than they do in public.


A number of prominent climate scientists representing the scientific consensus on climate change, as documented by the IPCC, have tried their best to convey the message in public forums, but were mostly shunned by conservative media. At the same time many climate scientists tend to regard the IPCC-based climate consensus as too optimistic. An article titled When the End of Human Civilization Is Your Day Job (Richardson, 2015) states … “Among many climate scientists, gloom has set in. Things are worse than we think, but they can’t really talk about it … Climate scientists have been so distracted and intimidated by the relentless campaign against them that they tend to avoid any statements that might get them labelled “alarmists”, instead retreating into a world of charts and data.“

As stated by Noam Chomsky: “It’s interesting that these public climate debates leave out almost entirely a third part of the debate, namely a very substantial number of scientists, competent scientists, who think that the scientific consensus is much too optimistic. A group of scientists at MIT came out with a report about a year ago describing what they called the most comprehensive modelling of the climate that had ever been done. Their conclusion, which was unreported in public media as far as I know, was that the major scientific consensus of the international commission is just way off, it’s much too optimistic … their own conclusion was that unless we terminate use of fossil fuels almost immediately, it’s finished. We’ll never be able to overcome the consequences. That’s avoided in the debate.”

Antarctica is losing ice at an average rate of more than 150 billion tons per year, and Greenland is losing more than 270 billion tons per year, adding to sea level rise. Some glaciologists and Arctic scientists consider the accelerated rate of glacial melt in Greenland and West Antarctica may result in little remaining ice over these terrains toward the end of the century, leading to sea level rise on the scale of many meters, with catastrophic consequences for coastal and river valley population centres.

The Arctic Ocean contains vast amounts of carbon accumulated during the Pleistocene ice ages. The greenhouse effect of methane traps up to 100 times more heat in the atmosphere than carbon dioxide within a 5 year period, and 72 times more within a 20 year period. Atmospheric levels of greenhouse gases – carbon dioxide, methane, and nitrous oxide – continued their climb during 2023 according to the latest measurements from NOAA and CIRES scientists. The current CO₂ growth rate threatens an irreversible shift in the state of the Earth climate through looming tipping points, including transient cooling events induced by flow of cold ice melt water into the oceans from Greenland and Antarctica; Glikson (2019).

Figure 4. Carbon dioxide at Mauna Loa, Hawaii.


There is little evidence that climate science had much of an effect on the outcome of the Paris Agreement. The warming target of +1.5°C has already been breached over the continents or is masked by the reflective albedo of transient sulphur aerosols. At the current growth rate of ~3 ppm/year CO₂ will rise closer to the stability threshold of the polar ice sheets.

Little encouragement can be gained from the non-binding promises emerging from climate conferences, which James Hansen described as a “fraud”.

While the implications of the global climate emergency have reached the defence establishment, the world continues to spend near to $2.4 trillion each year on the military instead on the protection of life.

As the portents for a major mass extinction of species are rising – who will defend life on Earth?


A/Prof. Andrew Y Glikson
Earth and climate scientist

Andrew Glikson
Books:

The Asteroid Impact Connection of Planetary Evolution
https://www.springer.com/gp/book/9789400763272
The Archaean: Geological and Geochemical Windows into the Early Earth
https://www.springer.com/gp/book/9783319079073
The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth
https://www.springer.com/gp/book/9783319572369
The Event Horizon: Homo Prometheus and the Climate Catastrophe
https://www.springer.com/gp/book/9783030547332
Climate, Fire and Human Evolution: The Deep Time Dimensions of the Anthropocene
https://www.springer.com/gp/book/9783319225111
Evolution of the Atmosphere, Fire and the Anthropocene Climate Event Horizon
https://www.springer.com/gp/book/9789400773318
From Stars to Brains: Milestones in the Planetary Evolution of Life and Intelligence
https://www.springer.com/us/book/9783030106027
Asteroids Impacts, Crustal Evolution and Related Mineral Systems with Special Reference to Australia
https://www.springer.com/us/book/9783319745442
The Fatal Species: From Warlike Primates to Planetary Mass Extinction
https://www.springer.com/gp/book/9783030754679
The Trials of Gaia. Milestones in the evolution of Earth with reference to the Antropocene
https://www.amazon.com.au/Trials-Gaia-Milestones-Evolution-Anthropocene/dp/3031237080




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Monday, July 8, 2024

Temperature rise threatens to accelerate even more

Global temperature

[ from earlier post ]

The above image, from an earlier post, shows that the February 2024 temperature was 1.76°C above 1885-1915, potentially 2.75°C above pre-industrial (bright yellow inset right). The image was created by Sam Carana for Arctic-news.blogspot.com with an April 2024 data.giss.nasa.gov screenshot. The red line (6 months Lowess smoothing) highlights the steep rise that had already taken place in early 2023. 

The image below, created with Climate Reanalyzer content, shows that June 2024 was substantially hotter than June 2023, which is significant since we're not in an El Niño anymore. Moreover, monthly temperatures are also rising.



According to Copernicus, the global-average temperature for the past 12 months (July 2023 – June 2024) has been more than 1.5°C above the 1850-1900 average. Carlo Buontempo, Director of the Copernicus Climate Change Service (C3S), adds: "June marks the 13th consecutive month of record-breaking global temperatures, and the 12th in a row above 1.5°C with respect to pre-industrial. This is more than a statistical oddity and it highlights a large and continuing shift in our climate." Note that anomalies from a genuinely pre-industrial base could be much higher, as the image at the top discusses.

Carbon dioxide growth

CO₂ at Mauna Loa was 426.91 ppm in June 2024, 3.23 ppm above June 2023, close to the 3.36 ppm growth in 2023, which is the highest annual growth on record up to now, as illustrated by the compilation image below, created with NOAA content. 


Furthermore, CO₂ in June is typically lower than it is in May, but it was (slightly) higher in June 2024 than it was in May 2024.

Sea surface temperatures

On July 9, 2024, sea surface temperatures were back at about 21°C again. For more than a year, sea surface temperatures have been at around 21°C, much higher than in previous years, as illustrated by the image below. 


Feedbacks and further developments

Higher temperatures come with feedbacks, as illustrated by the image below, from an earlier post.


[ from earlier post ]

Deformation of the Jet Stream enables strong winds to develop over the North Atlantic, which can at times strongly accelerate the speed at which hot water is flowing toward the Arctic Ocean along path of the Gulf Stream.

A deformed Jet Stream combined with high sea surface temperatures can temporarily speed up this flow, by strengthening storms and hurricanes along the path of the Gulf Stream, resulting in huge amounts of ocean heat to get abruptly pushed into the Arctic Ocean.

The image below shows sea surface temperatures as high as 32.5°C on July 11, 2024, with hot water getting pushed along the path of the Gulf Stream from the Gulf of Mexico toward the Arctic Ocean. 


The danger is that such feedbacks and further developments will accelerate the temperature rise even more. Critical in this respect is the condition of Arctic sea ice. 

Arctic sea ice decline

The image below, adapted from the Danish Metereological Institute, indicates that Arctic sea ice volume is at a record low for the time of year, as it has been for most of the year. At the same time, sea ice extent is still relatively large; Arctic sea ice extent was 3% below average in June 2024, close to the values observed most years since 2010, according to Copernicus. The implication is that sea ice must be very thin. 

The combination image below, from an earlier post and adapted from the University of Bremen, indicates that most of the thicker sea ice has melted in the course of June 2024, and that the latent heat buffer may be gone soon.


Latent heat buffer

Sea ice constitutes a buffer that consumes ocean heat; the temperature of the water will not rise as long as there is ice, but once all ice has melted, further heat will raise the temperature of the water. 


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

[ The Buffer has gone, feedback #14 on the Feedbacks page ]
Loss of the latent heat buffer threatens to strongly heat up the Arctic Ocean, and this increases the danger that further heat will reach methane hydrates at the seafloor of the Arctic Ocean, causing them to get destabilized resulting in eruption of methane from these hydrates and from free gas underneath that was previously sealed by the hydrates. 

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

• Climate Reanalyzer
https://climatereanalyzer.org

• Copernicus: June 2024 marks 12th month of global temperature reaching 1.5°C above pre-industrial 
https://climate.copernicus.eu/copernicus-june-2024-marks-12th-month-global-temperature-reaching-15degc-above-pre-industrial

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

• Carbon dioxide keeps rising in June 2024 
https://arctic-news.blogspot.com/2024/07/carbon-dioxide-keeps-rising-in-june-2024.html

• Did the climate experience a Regime Change in 2023? 
https://arctic-news.blogspot.com/2024/04/did-the-climate-experience-a-regime-change-in-2023.html

• NOAA - Global Monitoring Laboratory - Carbon Cycle Greenhouse Gases




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