Arctic News: Arctic

Showing posts with label Arctic. Show all posts

Saturday, January 18, 2025

Why downplay the need for action?

The 2024 global average surface temperature was 1.55°C above the 1850-1900 average, according to WMO’s consolidated analysis of six datasets.

[ click on images to enlarge ]

Differences between datasets are mainly due to the ways temperatures are measured, e.g. ERA5 measures the temperature of the air above oceans, whereas NASA and NOAA measure the surface temperature of the water, which is lower. There can also be differences in how temperatures are measured in areas with sea ice - the sea ice can be measured, or the water underneath the sea ice, or the air above the sea ice. Also, in some areas there once was sea ice that has meanwhile disappeared. Different ways of measuring things can raise the temperature record by as much as 0.2°C and even more in case of earlier years, where the margin of error is also larger.

Importantly, the temperature rise in the above image is compared to the period 1850-1900, which is not pre-industrial. When using a genuinely pre-industrial base, the temperature anomaly may already have been above the 2°C threshold in 2015, when politicians at the Paris Agreement pledged that this threshold wouldn't be crossed.

[ from earlier post ]

“Individual years pushing past the 1.5 degree limit do not mean the long-term goal is shot", UN Secretary-General Antóno Guterres says: “It is important to emphasize that a single year of more than 1.5°C for a year does NOT mean that we have failed to meet Paris Agreement long-term temperature goals, which are measured over decades rather than an individual year", WMO Secretary-General Celeste Saulo adds.

However, for this argument to hold, the average anomaly would need to fall to under 1.5°C from now. Should we really have to wait for another decade or two, before a confirmation is allowed to be issued that 1.5°C has been crossed. Isn't such a mandate part of downplaying how dire the situation is, an effort to delay the necessary action? Moreover, does such a mandate make sense?

[ click on images to enlarge ]

[ for more background, also view the Extinction page ]

To illustrate this point, the above image uses NASA anomalies (blue dots) that are conservatively compared to NASA's default 1951-1980 base, with data going back to 2010. The image thus shows a 30-year review period centered around January 1, 2025. Eight imaginary years of data have been added beyond existing data, extending the trend into the future (yellow dots). The wide pink trend is based on both NASA existing data and these imaginary data, jointly covering data from 2010-2032. The narrow black trend is not based on imaginary data, it is purely based on existing data, from 2010-2024, showing the potential for such a trend to eventuate when using existing (i.e. past) data only.

In case such a trend would indeed eventuate, confirmation of the crossing of the 1.5°C threshold should NOT be delayed until all the years of a 30-year period have been entirely completed. In fact, 2°C (vs 1951-1980) would already be crossed early 2026. In the course of 2032, a 16°C rise would be reached, while the average anomaly for the period 2010-2032 would be higher than 3°C (vs 1951-1980) with still 7 years to go before the 30-year period would be completed.

Warnings about the potential for such a rise have been sounded before, e.g. see the extinction page.

See also the image below with daily data.

[ temperature anomaly with ENSO shading, trends added, from an earlier post ]

Human extinction at 3°C

If the temperature does indeed keep rising rapidly, the anomaly compared to pre-industrial may soon or already be higher than 3°C, implying that humans are already functionally extinct, especially if no decisive, comprehensive and effective action is taken.

Analysis by Shona and Bradshaw found that, due to co-extinction, global biodiversity collapse occurs at around 5°C heating, as discussed in a 2019 post with the warning that a rise of more than 5°C could happen within a decade, possibly by 2026, and that humans who depend on many other species will likely go extinct with a 3°C rise.

A recent study by Joseph Williamson et al. finds that many species that live together appear to share remarkably similar thermal limits. That is to say, individuals of different species can tolerate temperatures up to similar points. This is deeply concerning as it suggests that, as ecosystems warm due to climate change, species will disappear from an ecosystem at the same time rather than gradually, resulting in sudden biodiversity loss. It also means that ecosystems may exhibit few symptoms of heat stress before a threshold of warming is passed and catastrophic losses occur.

Arctic sea ice

[ Arctic sea ice extent, click on images to enlarge ]

During the first few months of the year, Arctic sea ice is still growing in extent. In the above image, the red line and red marker shows 2025 sea ice extent. Dots mark Arctic sea ice extent on January 19 for the respective year and Arctic sea ice extent was at a record low for the time of year on January 19, 2025, despite La Niña conditions.

A new El Niño may emerge in the course of 2025, while both Arctic sea ice extent and volume are at record low, while numerous self-reinforcing feedbacks are kicking in with accelerating ferocity and while further mechanisms are active that drive up temperatures such as high sunspots. Such a combination of mechanisms could cause a huge temperature rise and a Blue Ocean Event in 2025, threatening huge amounts of methane to erupt from the seafloor.

[ Arctic sea ice volume, click to enlarge ]

On Jan 18, 2025, the sea surface temperature south of Svalbard (green circle) was 5.1°C, 3.4°C higher than 1981-2011, as the above image shows.

High ocean temperatures result in low Arctic sea ice volume, as illustrated by the image on the right and discussed in this earlier post.

Guy McPherson discussed the consequences of an ice-free Arctic Ocean in the video below, adding that "a near-term, ice-free Arctic Ocean—the so-called Blue Ocean Event—is the extinction-causing event over which we have the least control. The rate of environmental change in the wake of such an event will suffice to cause the extinction of all life on Earth.

I’m not a fan."

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

• WMO confirms 2024 as warmest year on record at about 1.55°C above pre-industrial level
https://wmo.int/news/media-centre/wmo-confirms-2024-warmest-year-record-about-155degc-above-pre-industrial-level

• Met Office - 2024: record-breaking watershed year for global climate
https://www.metoffice.gov.uk/about-us/news-and-media/media-centre/weather-and-climate-news/2025/2024-record-breaking-watershed-year-for-global-climate

• Berkeley Earth - Global Temperature Report for 2024
https://berkeleyearth.org/global-temperature-report-for-2024

• NASA - Goddard Institute Surface Temperature (GISTEMP v4) analysis
https://data.giss.nasa.gov/gistemp

• NASA - Temperatures Rising: NASA Confirms 2024 Warmest Year on Record

https://www.nasa.gov/news-release/temperatures-rising-nasa-confirms-2024-warmest-year-on-record

• NOAA - 2024 was the world’s warmest year on record
https://www.noaa.gov/news/2024-was-worlds-warmest-year-on-record

• Paris Agreement
https://unfccc.int/process-and-meetings/the-paris-agreement

• pre-industrial

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

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

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

• Clustered warming tolerances and the nonlinear risks of biodiversity loss on a warming planet - by Joseph Williamson et al.

https://royalsocietypublishing.org/doi/10.1098/rstb.2023.0321

also discussed on Facebook at:

https://www.facebook.com/groups/arcticnews/posts/10162295497964679

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

• Arctic and Antarctic Data Archive System (ADS) of the National Institute of Polar Research of Japan
https://ads.nipr.ac.jp

• nullschool.net
https://earth.nullschool.net

• Double Blue Ocean Event 2025?

https://arctic-news.blogspot.com/2024/10/double-blue-ocean-event-2025.html

• Guy McPherson - consequences of an ice-free Arctic Ocean

https://www.youtube.com/watch?v=sK97O9Buqmk

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

• The first ice-free day in the Arctic Ocean could occur before 2030 - by Céline Heuzé et al. https://www.nature.com/articles/s41467-024-54508-3

als0o discussed on facebook at:

https://www.facebook.com/groups/arcticnews/posts/10162207185219679

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

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

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

Wednesday, July 31, 2024

Thickest sea ice breaking away from Greenland

Large pieces of sea ice are breaking away from the northern tip of Greenland, to be carried by ocean currents to the Fram Strait east of Greenland. On their way they will melt away, illustrating how ocean heat can make even the thickest parts of the sea ice disappear in a matter of days.

The thick sea ice north of Greenland is breaking away due to high ocean heat and due to strong wind blowing from Greenland toward the North Pole, which is in turn due to deformation of the Jet Stream, one of the many feedbacks of the temperature rise.

[ click on images to enlarge ]

The above image shows wind at 250 hPa and sea surface temperatures. Sea surface temperatures as high as 1.2°C (34.2°F) show up at the green circle just north of Greenland, on July 30, 2024.

On the right is a Naval Research Laboratory animation of Arctic sea ice thickness through July 29, 2024, with forecasts added through August 6, 2024.

The animation below shows a NASA Worldview animation of satellite images from July 25, 2024 to July 29, 2024. This is a 6.5 MB file, so if it doesn't show up due to its size, you may be able to view it by clicking on the Facebook comment box underneath.

[ click on images to enlarge ]

The animation below shows the thickest Arctic sea ice breaking away from Greenland between July 24, 2024, and August 1, 2024.

Deformation of the Jet Stream

The Arctic Ocean is heating up as a result of increases in ocean heat and air temperatures. As sea ice melts away, feedbacks such as albedo changes further speed up the temperature rise. The Arctic Ocean is also heating up due to higher temperatures of river water. The temperature was as much as 14.8°C or 26.6°F higher than 1981-2011 at a location where water of the Ob River is flowing into the Arctic Ocean (green circle), as illustrated by the image below.

The image below shows the situation on August 2, 2024, when sea surface temperatures were as much as 15.8°C or 28.4°F higher than 1981-2011 where water of the Ob River is flowing into the Arctic Ocean (green circle). The image also shows wind at 250 hPa, illustrating deformation of the Jet Stream, with many circular wind patterns, another feedback of the temperature rise.

Permafrost decline results in more meltwater entering the Arctic Ocean from rivers. Deformation of the Jet Stream can strengthen heatwaves that heat up river water, causing a lot more heat to enter the Arctic Ocean. A deformed Jet Stream can also strengthen storms and rainfall, further speeding up the thawing of permafrost and resulting in more run-off of water into the Arctic Ocean. Furthermore, deformation of the Jet Stream can at times strengthen wind patterns that speed up the flow of rivers and ocean currents, speeding up disintegration of sea ice and resulting in more heat getting abruptly pushed into the Arctic Ocean.

The combination image below shows, on the left, a 16.7°C or 62.1°F sea surface temperature recorded on August 8, 2024, off the coast where the Mackenzie River flows into the Arctic Ocean (green circle); the Jet Stream shows many circular patterns and an omega pattern over the area with the green circle. On the right, the image shows a 34°C or 93.1°F surface temperature over land recorded on August 8, 2024, south of where the Mackenzie River enters the Arctic Ocean (green circle).

[ click on images to enlarge ]

Deformation of the Jet Stream enables heatwaves to extend over the Arctic Ocean, with high air temperatures speeding up sea ice decline, while hot water from rivers further speeds up sea ice decline, resulting in loss of albedo, loss of the latent heat buffer and further changes that jointly speed up the temperature rise and further deform the Jet Stream.

The image below, from an earlier post, illustrates how multiple feedbacks and their interaction can accelerate the temperature rise.

In conclusion, deformation of the Jet Stream can contribute to higher temperatures by strengthening extreme weather events such as circular wind patterns, heatwaves, fires, storms, lightning and rainfall, i.e. by strengthening their intensity, frequency, duration and area covered, as also discussed and illustrated in earlier posts such as this one.

Further illustrating this is the image below, which shows numerous fires in Canada that cause emissions that in turn cause black carbon to be deposited on sea ice and permafrost, speeding up their decline and the temperature rise.

Links

• Nullschool

https://earth.nullschool.net

• Naval Research Laboratory

https://www7320.nrlssc.navy.mil/GLBhycomcice1-12/arctic.html

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

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.

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

Discussed at Facebook at:
https://www.facebook.com/groups/arcticnews/posts/10161520778324679

• 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

https://gml.noaa.gov/ccgg/trends

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

• Copernicus - Sea ice cover for June 2024
https://climate.copernicus.eu/sea-ice-cover-june-2024

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

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

• 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

Wednesday, July 3, 2024

Feedbacks

Water vapor feedback

There are numerous self-amplifying feedbacks that accelerate the temperature rise. One of them is the water vapor feedback. Just the temperature rise itself will cause more water vapor to be in the atmosphere.

[ from Moistening Atmosphere ]

The February 2024 temperature was 1.76°C above 1885-1915, which could be as much as 2.75°C above the pre-industrial temperature.

A 2.75°C rise corresponds with almost ⅕ more water vapor in the atmosphere, as the extinction page points out.

The increase in water vapor in the atmosphere is a self-amplifying feedback, since water vapor is a powerful greenhouse gas, accelerating the temperature rise, as illustrated by the image on the right.

As illustrated by the image below, created with NOAA data, surface precipitable water reached 26.741 kg/m² in June 2024.

As the above image also illustrates, surface precipitable water reached a record high of 27.139 kg/m² in July 2023, and was much higher for each of the first six months in 2024 than for the same months in 2023.

More emissions of greenhouse gases (from earlier post)

As temperatures rise, due to stronger emissions of carbon dioxide, methane and nitrous oxide, there will be a corresponding extra amount of water vapor in the atmosphere.

Studies such as by Hubau (2020) warn that the uptake of carbon into Earth’s intact tropical forests peaked in the 1990s. Thawing permafrost can cause huge emissions of carbon dioxide, methane and nitrous oxide. Studies now warn that the Arctic has also changed from sink to source.

A study by Del Vecchi et al. (2024) suggests that a gradual thawing of Arctic permafrost could release between 22 billion and 432 billion tons of carbon dioxide by 2100 if current greenhouse gas emissions are reined in — and as much as 550 billion tons if they are not.

An analysis by Ramage et al. (2024) concludes that Arctic terrestrial permafrost now emits more greenhouse gases than it stores, and the trend is likely to accelerate as temperatures keep rising in the Arctic. The highest carbon dioxide emissions over the 2000-2020 period came from inland rivers and wildfires. The non-permafrost wetlands exhaled the most methane, and dry tundra released the most nitrous oxide.

The prospect of further releases looks dire. The analysis gives estimates that the upper three meters of permafrost region soils store 1,000 Gt of soil organic carbon, while deeper deposits could store an additional amount of as much as 1,000 Gt C. The analysis concludes that the permafrost region is the largest terrestrial carbon and nitrogen pool on Earth.

Note that the joint CO₂e of emissions in this analysis only covers part of global emissions, e.g. the analysis excludes emissions from Arctic subsea permafrost and from oceans in general, from many mountain areas and from the Southern Hemisphere. The study also appears to have excluded emissions caused by anthropogenic disturbances such as clear-cutting, logging and fracking activities in the region, while calculations typically use a low global warming potential (GWP) for methane (100-year horizon).

Miesner et al. (2023) warn that an additional 2822 Gt of organic carbon is stored in subsea Arctic shelf permafrost and Huang et al. (2024) warn that the top two meters of soil globally holds about 2300 Gt of inorganic carbon, which has been left out of environmental models, and 23 Gt of this carbon may be released over the next 30 years.

The transition from sink to source of the region is an important feedback of the temperature rise that is not fully reflected in many climate models. According to the IPCC, 14–175 Gt CO₂e (in carbon dioxide and methane) gets released per 1°C of global warming, which is likely to underestimate the situation by downplaying many feedbacks. Despite the dire situation, the IPCC keeps promoting less effective policies such as support for biofuel and tighter fuel efficiency standards, as discussed in earlier posts such as this 2022 one.

Further feedbacks

The image below illustrates the mechanism of how multiple feedbacks accelerate the heating up of the atmosphere.

Feedback #1: albedo loss (loss of reflectivity) as sea ice melts due to rising temperatures and due to the ice getting covered by soot, dust, algae, meltpools and rainwater pools;

Feedback #14: loss of the latent heat buffer - as sea ice disappears, heat can no longer be consumed by the process of melting, and the heat will instead go into increasing the temperature;

Feedback #16: eruptions of seafloor methane - as more heat reaches the seafloor of the Arctic Ocean, sediments and hydrates contained in them destabilize, resulting in methane releases;

Feedback #25: extra water vapor feedback - rising temperatures will result in more water vapor 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;

Feedback #19: distortion of the Jet Stream as the temperature difference narrows between the Arctic and the Tropics, in turn causing further feedbacks to kick in stronger, such as hot air moving into the Arctic and cold air moving out, and more extreme weather events bringing heavier rain and more intense heatwaves, droughts and forest fires that cause black carbon to settle on the sea ice;

Feedback #28: freshwater lid on the North Atlantic - melting of sea ice and glaciers and thawing of the permafrost results in meltwater accumulating in the North Atlantic, where it forms a cold freshwater lid on top of the water; this lid grows further due to more rain falling on top of this lid. This results in less evaporation and transfer of heat from the North Atlantic to the atmosphere, and more ocean heat getting carried by the Gulf Stream underneath the sea surface into the Arctic Ocean.

There is interaction between feedbacks; the image's focus is on illustrating the mechanism, rather than the proportional contribution or the order of feedbacks over time. Sea ice decline comes with both loss of albedo and loss of the latent heat buffer, each of which will accelerate the temperature rise of the water of the Arctic Ocean, thus contributing to the threat that hydrates contained in sediments at the seafloor of the Arctic Ocean will be destabilized, which in turn threatens to cause eruption of huge amounts of methane.

A further danger lies in changes occurring to wind and ocean current patterns; the temperature rise will cause stronger wind, waves and storms, as well as deformation of the Jet Stream. In addition, the temperature rise causes loss of reflectivity of clouds and more ocean stratification, exacerbated by more freshwater accumulating at the surface of oceans, due to stronger ice melting, due to heavier runoff from land and rivers and due to changes in wind patterns and ocean currents and circulation. In the North Atlantic, there is the additional danger that formation of a freshwater lid will cause huge amounts of ocean heat to be pushed into the Arctic Ocean and enter the atmosphere as sea ice disappears.

Further developments

Furthermore, developments such as rising emissions from industry, transport, land use, forest fires and waste fires, ocean acidification and reductions in sulfur emissions can all contribute to further acceleration of the temperature rise.

Links

• Moistening Atmosphere
https://arctic-news.blogspot.com/p/moistening-atmosphere.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

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

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

• NOAA - Physical Sciences Laboratory
https://psl.noaa.gov

• Arctic Sea Ice Alert

https://arctic-news.blogspot.com/2024/06/arctic-sea-ice-alert.html

• Will there be Arctic sea ice left in September 2023?

https://arctic-news.blogspot.com/2023/05/will-there-be-arctic-sea-ice-left-in-september-2023.html

Monday, June 24, 2024

How hot will it get?

Temperatures as high as 125°F or 51.67°C are forecast to hit California on July 6, 2024, as illustrated by the image below, adapted from Climate Reanalyzer by the University of Maine.

On June 23, 2024, the temperature in the Northern Hemisphere was higher than it was last year at this time of year, as illustrated by the image below, created with University of Maine content. The image shows that a temperature of 21.5°C was reached in the Northern Hemisphere on June 23, 2024. The question is: Will temperatures over the next few months exceed the high temperatures reached last year?

El Niño is no longer prevalent and La Niña conditions are expected to be dominant soon, as illustrated by the NOAA ENSO update on the right, from an earlier post.

Nonetheless, there are fears that temperatures will remain high and continue to rise, as self-amplifying feedbacks have taken over as the dominant drivers of the temperature rise. This was discussed earlier, in recent posts such as this one and this one.

There are numerous feedbacks that can further accelerate the temperature rise. Higher temperatures come with more water vapor in the atmosphere, an important feedback since water vapor is also a potent greenhouse gas.

Surface precipitable water reached a record high of 27.139 kg/m² in July 2023, as illustrated by the image below, adapted from NOAA, from an earlier post. Worryingly, a value of 26.138 kg/m² was reached in May 2024, much higher than the 25.378 kg/m² in May 2023, which raises fears that surface precipitable water will reach an even higher peak in 2024 than was reached in 2023.

Rising temperatures speed up the decline of sea ice and permafrost, which can in turn result in huge emissions of carbon dioxide, methane and nitrous oxide.

The decline of permafrost results in more meltwater that speeds up the flow of rivers. The image on the right shows sea surface temperatures as high as 18.3°C in the Bering Strait on June 29, 2024.

Deformation of the Jet Stream is another important feedback and it particularly affects the Northern Hemisphere where the Arctic heats up more rapidly than the rest of the world, thus narrowing the temperature difference between the Tropics and the Arctic, which changes the shape of the Jet Stream.

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 that come with forest fires on land.

On land, more extreme weather can cause strong rainfall, resulting in more water running off into the Arctic Ocean. As heatwaves cause the water of rivers to heat up, a lot more heat can enter the Arctic Ocean.

Heatwaves and increased lightning can also cause fires that result in emissions and cause black carbon to settle on ice, causing temperature rise due to albedo loss and speeding up the thawing of permafrost and melting of sea ice. The image below, adapted from Copernicus, shows biomass burning aerosols, i.e. a forecast for June 29, 2024.

Over oceans, the impact of deformation of the Jet Stream can be even larger, since wind tends to be stronger over oceans than over land. Near the ocean, the greater temperature difference between land and sea will result in stronger winds.

The image below shows sea surface temperatures in the Northern Hemisphere. Heavy melting occurs in the blue-colored areas. Where the sea ice has disappeared, red and yellow colors show up, indicating temperatures higher than they used to be at this time of year in the respective area. High anomalies result from the loss of the latent heat buffer that previously absorbed heat and from the albedo changes that result in more sunlight getting absorbed by the surface.

Furthermore, the image shows a deformed Jet Stream with many circular wind patterns (at 250 hPa) over the Arctic. Deformation of the Jet Stream contributes to these high temperatures, by enabling heatwaves to extend over the Arctic Ocean, increasing not only the intensity, but also the frequency, duration and areas covered by such events.

The above image shows sea surface temperatures as high as 8.2°C or 46.7°F (i.e. 4.5°C or 8.1°F higher than 1981-2011) in the Laptev Sea (at the green circle), illustrating how a deformed Jet Stream is moving hot air over the Arctic Ocean and is also heating up the water of the Lena River and accelerating the speed at which the water is flowing into the Arctic Ocean.

The image below shows sea surface temperatures as high as 15.4°C or 59.7°F (i.e. 14.9°C or 26.8°F higher than 1981-2011) in Hudson Bay (at the green circle), while a deformed Jet Stream is moving hot air from Siberia far over the Arctic Ocean.

[ click on images to enlarge ]

A deformed Jet Stream can temporarily speed up this flow, causing huge amounts of ocean heat to get abruptly pushed 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 32.3°C on June 22, 2024.

As Arctic temperatures keep rising, two tipping points threaten to get crossed as temperatures rise and Arctic sea ice disappears, i.e. the latent heat tipping point and the seafloor methane tipping point, as discussed in an earlier post.

The combination image below, 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.

As illustrated by the image below, adapted from IRI, La Niña may develop during July-September 2024. A combination of feedbacks and their interaction, including the water vapor feedback, deformation of the Jet Stream and loss of albedo and loss of the latent heat buffer, may cause a continuation of high temperatures even during this La Niña. A new El Niño may develop in 2025 and be prevalent in 2026.

In other words, we may move into the next El Niño while the temperature rise keeps accelerating, while the masking effect of aerosols gets further reduced and while sunspots are moving toward a peak (in July 2025).

Links

• Climate Reanalyzer
https://climatereanalyzer.org

• Arctic Sea Ice Alert

https://arctic-news.blogspot.com/2024/06/arctic-sea-ice-alert.html