Saturday, July 12, 2025

Will humans go extinct soon?

The image below shows the June 2025 temperature anomaly versus 1951-1980, using ERA5 data.

[ June 2025 temperature anomaly, click on images to enlarge ]
    [ from earlier post, click to enlarge ]
The above image shows relatively low anomalies over the Arctic Ocean, with a relatively cool area persisting in the North Atlantic, south of Greenland. This appears to reflect heavy melting, slowing down of the Atlantic Meridional Overturning Circulation (AMOC) and strong evaporation followed by more rainfall further down the track of the Gulf Stream, as illustrated by the image on the right.

The above image also shows very high anomalies over Antarctica and over the Antarctic sea ice. This appears to reflect a reversal of the Southern Meridional Overturning Circulation (SMOC).

   [ marine heatwave in North Pacific ]
The image on the right shows that the sea surface temperature was as much as 7.5°C (13.4°F) higher than 1981-2011 on July 16, 2025, 12:00 UTC, at the location marked by the green circle, reflecting a strong marine heatwave in the North Pacific. The image also shows a distorted Jet Stream (at 250 hPa).

Rising temperatures result in a loss of carbon storage, concludes a recent study led by Thomas Werner into marine heatwaves. 

Covering more than 70% of Earth’s surface, our global ocean has absorbed 90% of the warming that has occurred in recent decades due to increasing greenhouse gases, and the top few meters of the ocean store as much heat as Earth's entire atmosphere, as described by a NASA post. 

A small change in this ratio could result in a huge rise in the global air temperature, and studies warn about changes that are occurring in the AMOC and SMOC, as discussed in earlier posts such as this one.

A 2024 study led by Judd finds that climate sensitivity has historically been about 8°C. According to James Hansen, equilibrium global warming for today’s amount of greenhouse gases is 10°C, which includes a 2°C rise that would eventuate by the falling away of the aerosols that currently mask the temperature rise.

    [ NOAA ENSO outlook ]
Meanwhile, the IPCC keeps down-playing the potential impact of feedbacks such as changes to ocean currents, wind patterns, clouds, water vapor, sea ice and permafrost, thus failing to warn that the temperature is likely to rise strongly with a new El Niño and with further reduction of the aerosol masking effect, triggering numerous feedbacks to kick in and more extreme weather events to strike with greater ferocity, frequency and ubiquity. 

For now, ENSO-neutral conditions dominate and are expected to persist during the Northern Hemisphere fall and winter 2025-2026 (image right).

The current ENSO-neutral conditions make it even more significant that on July 14, 2025, the global temperature was 16.86°C, as illustrated by the image below, adapted from Climate Reanalyzer. 


The earlier image below shows a preliminary 16.85°C that was later upgraded to 16.86°C (final). The point is that this is a record high for that day and 0.3°C below the highest daily temperature on record (17.16°C) that was reached on July 22, 2024 (image adapted from Copernicus).

The image below shows monthly temperature anomalies through June 2025, based on ERA5 anomalies vs 1951-1980 from Jan 2014-June 2025 (red circles). 
In the above image, data are adjusted by 1°C to reflect a pre-industrial base (black circles). Cubic trends are added to show that 3°C could be crossed late 2028 (red) or early 2027 (black). 

The image below shows surface air temperature anomalies April 1, 2023, through July 14, 2025 (final), with a red trend added that warns about a potentially huge temperature rise later in 2025.


Furthermore, sea surface temperatures are on the rise again. The image below shows the global sea surface temperature through July 20, 2025 (60°S–60°N, 0–360°E).


How much could temperatures rise? The image below is a combination image. The top image shows a trend based on annual sea surface temperature anomalies in the Northern Hemisphere through 2022. The bottom image shows a trend based on annual sea surface temperature anomalies in the Northern Hemisphere through 2023. The trend in the bottom image shows an even steeper rise than the trend in the top image. This shows that a polynomial trend can sometimes be a good indicator of the rise to come.


The image below repeats the IPCC's response, or rather its failure to respond.


A 3°C rise constitutes an important threshold, since humans will likely go extinct with such a rise. As illustrated by the image below, we may already be more than 2°C above pre-industrial and face a potentially huge temperature rise over the next few years.

[ from the post When will humans go extinct? ]
   [ from: When Will We Die? ]
Recent research led by David Fastivich finds that, historically, vegetation responded at timescales from hundreds to tens of thousands of years, but not at timescales shorter than about 150 years. It takes centuries for tree populations to adapt - far too slow to keep pace with today’s rapidly warming world.

Note that vegetation depends on the presence of a lot of things including healthy soil, microbes, moisture, nutrients and habitat. 

A 2018 study by Strona & Bradshaw indicates that most life on Earth will disappear with a 5°C rise (see box on the right). Humans, who depend on a lot of other species, will likely go extinct with a 3°C, as discussed in the earlier post When Will We Die? 

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

• Saltier water, less sea ice
https://arctic-news.blogspot.com/2025/07/saltier-water-less-sea-ice.html

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

• Marine heatwaves as hot spots of climate change and impacts on biodiversity and ecosystem services - by Thomas Wernberg et al.
discussed on Facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10162992131044679

• Copernicus
https://pulse.climate.copernicus.eu

• NASA - Ocean warming (December 2024) 
https://climate.nasa.gov/vital-signs/ocean-warming/?intent=121

• Arctic Blue Ocean Event 2025? (update June 2025)
https://arctic-news.blogspot.com/2025/06/arctic-blue-ocean-event-2025-update-June-2025.html

• A 485-million-year history of Earth’s surface temperature by Emily Judd et al. (2024) 
https://www.science.org/doi/10.1126/science.adk3705
discussed on Facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10161741588279679

• Global warming in the pipeline - by James Hansen et al. 
https://academic.oup.com/oocc/article/3/1/kgad008/7335889
discussed on Facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10161110558744679

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

• 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

• When will humans go extinct? 

• Coupled, decoupled, and abrupt responses of vegetation to climate across timescales - by David Fastovich et al. (2025)
discussed on Facebook at: 

• When Will We Die?

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

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

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




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Saturday, July 5, 2025

Arctic Blue Ocean Event? (update July 2025)


Arctic sea ice extent was 8.35 million km² on July 4, 2025, a record low extent for this time of year. This record daily low extent is the more significant since it was reached in the absence of El Niño conditions. Instead, ENSO-neutral and borderline La Niña conditions are currently dominant.

Sea ice extent is one out of several measurements indicating the miserable state the Arctic sea ice is in, as also discussed in an earlier post. The image below shows Arctic sea ice concentration on July 12, 2025.


The combination image below shows Arctic sea ice thickness on July 12, 2025 (left) and a sea surface temperature of 10.3°C or 50.6°F on July 10, 2025 (at the green circle, center), corresponding with a sea surface temperature anomaly of 11.4°C or 20.5°F on July 5, 2025 (at the green circle, right). 


Arctic sea ice volume was at a record daily low on July 11, 2025, as it has been for more than a year, as illustrated by the image below.
The Antarctic sea ice area fell from 11.72 million km² (17th place) on July 6, 2025, to 11.30 million km² (2nd place) on July 15, 2025, as illustrated by the image below.
Global sea ice extent was 21.99 million km² on July 18, 2025, a standard deviation of -5.06σ from 1981-2010, as illustrated by the image below. 

This very low global sea ice extent means loss of albedo, as a lot less sunlight now gets reflected back into space by global sea ice and instead gets absorbed by the sea surface. Low sea ice extent thus is a self-amplifying feedback loop that further drives up global temperatures, and this in turn threatens to strengthen numerous further self-amplifying feedback loops such as changes to ocean currents that cause more heat to accumulate at the ocean surface and darkening of the ocean surface, which further reduces the Earth's albedo, as warned about in a recent study led by Thomas Davies.

Will an Arctic Blue Ocean Event occur in 2025? 
[ from earlier post ]
Most climate models do not anticipate an Arctic Blue Ocean Event (BOE) to occur soon. For such a BOE to occur in 2025 would therefore count as a Black Swan event, i.e. something unexpected. Having said that, there are many things that most climate models didn't expect to occur, including: 

- Very high temperatures, starting in 2023 and still persisting this year 
- Very low Antarctic sea ice over the pasty few years 
- Record high concentrations of greenhouse gases 
- Heat rising from the Southern Ocean into the atmosphere, as discussed in an earlier post 
- Record low Earth's albedo (as illustrated by the image below) 

[ Earth's albedo, image from Eliot Jacobson, also discussed on facebook ]

[ James Hansen: Inferred contributions
to reduced Earth albedo ]
The image on the right, from an earlier post, shows inferred contributions to this drop in albedo, by Hansen et al.

There is a compound impact in that sea ice loss comes with albedo loss that causes more heat to be absorbed by oceans, while higher global sea surface temperatures also cause further loss of lower clouds, further reducing albedo and thus accelerating the temperature rise.

Polar amplification of the temperature rise narrows the temperature difference between the poles and the Equator, which causes distortion of the Jet Stream that in turn results in more extreme weather events. A 2025 study led by Tselioudis suggests that this causes the band of clouds over the Tropics to contract. Since clouds over the Tropics reflect relatively more sunlight, this results in reduced global albedo.

The extraordinary albedo loss depicted in the above image causes the temperature to rise, increasing the probability for a Blue Ocean Event to occur in the course of 2025. 

2024 temperature anomaly in the Northern Hemisphere: an 14.349σ event

Talking about probabilities, the 2024 world 2m temperature standard deviation from 1951-1980 was very high, an anomaly of 11.157 σ, as illustrated by the image below. 



In statistics, the empirical rule states that in a normal distribution, 68% of the observed data will occur within one standard deviation (1σ), 95% within two standard deviations (2σ), and 99.7% within three standard deviations (3σ) of the mean. A 4σ event indicates that the observed result is 4 standard deviations (4σ) away from the expected mean. In a normal distribution, 99.993666% of data points would fall within this range. The chance for data to fall outside of 4σ is thus infinitesimally small. The 2024 world temperature anomaly was an 11.157σ event.


In the Northern Hemisphere, the 2024 temperature anomaly was 1.701°C higher than the 1951-1980 mean, as illustrated by the above image. This constitutes a 14.349σ event, as illustrated by the image below.

The 2024 temperature anomaly in the Northern Hemisphere was much higher than the world 2024 temperature anomaly, as illustrated by the above images. The difference between the land and ocean anomalies is even larger, the 2024 temperature anomaly on land was 1.9°C, while the ocean anomaly was 0.92°C, as illustrated by the image below. 


   [ February 2024 NH anomaly ] 
Temperature anomaly peaks in specific areas can be much higher than global annual averages. As an example, temperature anomalies for February 2024 were 15-20°C higher than 1951-1980 in some areas, as illustrated by the map on the right. 

Note also that 1951-1980 is a relatively recent period; when compared with a genuinely pre-industrial base, temperature anomalies will be even higher.

In conclusion, to call the 2024 temperature anomaly on land in the Northern Hemisphere extraordinary is an understatement. There is an unacceptable danger that the temperature rise will accelerate further, hitting areas on land in the Northern Hemisphere hard, which is where after all most people live. 

Danger Assessment
[ image from earlier post ]
The very continuation of life on Earth is at stake and the sheer potential that all life on Earth may be condemned to disappear due to a refusal by some people to do the right thing, that should prompt the whole world into rapid and dramatic climate action.

Extreme heat stress warning

The image below highlights an extreme heat stress warning for Memphis, Tennessee, for July 22, 2025.


The image below shows a forecast for July 22, 2025, by Climate Reanalyzer. 



The image below shows an extreme heat stress warning for July 22, 2025, for locations in Tennessee. 



See also earlier warning for June 2025.

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

• National Institute of Polar Research Japan
https://ads.nipr.ac.jp

• Nullschool.net

• University of Bremen

• Kevin Pluck - sea ice visuals

• Darkening of the Global Ocean - by Thomas Davis et al. (2025)  
https://onlinelibrary.wiley.com/doi/10.1111/gcb.70227 
discussed on Facebook at:
https://www.facebook.com/groups/arcticnews/posts/10162720612504679

• Climate Reanalyzer

• Heads in the clouds while Earth is burning

• Saltier water, less sea ice

• Arctic Blue Ocean Event 2025? (update June 2025)

• NASA - GISS Surface Temperature Analysis

• National Weather Service - National Digital Forecast Database

• NOAA - heat risk graphics

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

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

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








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Wednesday, July 2, 2025

Saltier water, less sea ice

A study led by Alessandro Silvano (2025) finds that the deep ocean circulation in the Southern Hemisphere—known as the SMOC—is not only being altered, but has reversed. That is, instead of sinking into the depths, surface water is being replaced by deep water masses rising to the surface, bringing with them heat and carbon dioxide (CO₂) that could significantly increase atmospheric temperatures and CO₂ concentrations.
By combining satellite observations with data from underwater robots, researchers built a 15-year picture of changes in ocean salinity, temperature and sea ice, as illustrated by the above image. Around 2015, surface salinity in the Southern Ocean began rising sharply – just as sea ice extent started to crash. When surface waters become saltier, they sink more readily, stirring the ocean’s layers and allowing heat from the deep to rise. This upward heat flux can melt sea ice from below, even during winter, making it harder for ice to reform. This vertical circulation also draws up more salt from deeper layers, reinforcing the cycle.

In the video below, Paul Beckwith discusses  the study. 


Saltier water, less sea ice

   [ Saltier water, less sea ice ]
The higher the water's salt content, the lower its melting point. Seawater typically has a salinity of about 3.5% (35 grams of salt per liter of water). Sea ice starts melting when the temperature rises to about -2°C (28.4°F). By contrast, freshwater remains frozen as long as the temperature remains below 0°C (32°F).

What is causing the Southern Ocean surface to become more salty? Higher temperatures come with feedbacks, such as stronger evaporation resulting in both a lot more water vapor and a lot more heat getting transferred from the surface to the atmosphere. 

Much of the water vapor will return to the surface in the form of precipitation such as rain and snow, but part of this precipitation will fall over Antarctica. Increased snowfall over Antarctica can be attributed to rising air temperatures and stronger evaporation, changes in atmospheric circulation and the effects of ozone depletion. 

Furthermore, 7% more water vapor will remain in the atmosphere for every degree Celsius rise in temperature. Since water vapor is a potent greenhouse gas, this will further increase temperatures, making it a self-amplifying feedback that can significantly contribute to further acceleration of the temperature rise. 

Accumulating feedbacks

Warmer oceans result in stronger stratification (feedback #29), further contributing to make it harder for heat to reach the deeper parts of oceans. As a result, a larger proportion of the heat that was previously entering oceans will instead remain in the atmosphere or accumulate at the ocean surface, and slowing down of the overturning circulation further contributes to this. 
[ from earlier post ]
In conclusion, the Southern Ocean surface is becoming more salty, and this, in combination with higher sea surface temperatures, results in more melting of the sea ice. Less sea ice in turn comes with loss of albedo (water is less reflective than ice, feedback #1), 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 #14) and loss of emissivity (water is less efficient than ice in emitting in the far-infrared region of the spectrum, feedback #23), while warmer water comes with more water vapor and less low-level clouds that reflect sunlight back into space (feedback #25). 

The image below, from an earlier post, illustrates that higher temperatures come with feedbacks and the impact of one feedback can amplify the impact of other feedbacks.

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

• Rising surface salinity and declining sea ice: A new Southern Ocean state revealed by satellites - by Alessandro Silvano et al. (2025)
https://www.pnas.org/doi/full/10.1073/pnas.2500440122
discussed on facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10162876582119679

• Abrupt Antarctic Ocean Regime Shift: Reversed SMOC - Southern Meridional Overturning Circulation - video by Paul Beckwith 
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