Water near North Pole

Water is visible near the North Pole, as illustrated by the satellite image below, dated September 4, 2026.

With much water being visible near the North Pole, Arctic sea ice volume is currently not the lowest for the time of year, as illustrated by the image below. 

Why isn't Arctic sea ice volume currently at a record low? There still is a lot of relatively thick sea ice present North of Greenland and the Canadian Arctic Archipelago. The image below shows Arctic sea ice thickness on September 3, 2026.  

Rising temperatures and distortion of the Jet Stream can cause extreme weather events to become more extreme. Rising temperatures will result in more water vapor in the atmosphere (7% more water vapor for every 1°C warming). As illustrated by the combination image below, this can cause more snow to fall over the Arctic Ocean, which can thicken the sea ice or contribute to more freshwater at the surface. 

[ Forecasts for September 5, 2026. Click on images to enlarge ]

Stronger heatwaves and storms over land can also cause increasingly larger amounts of freshwater to get added to the surface of the Arctic Ocean in the form of water from rivers and from runoff from land, as illustrated by the image below. Less salty water can contribute to a temporary slowing down of Arctic sea ice melting, but given the speed at which the ocean heat keeps rising, such a slowdown looks set to be overwhelmed soon and huge melting of sea ice threatens to return with a vengeance, i.e. abruptly, as sea surface temperatures keep rising in line with the 2026 El Niño. 

Temperatures of the sea surface are very high, as much as 13°C or 23.3°F higher than 1981-2011 on September 4, 2026, in the Gulf of Ob (green circle on the above image). The image also shows that the cold area that was previously visible south of Greenland got overwhelmed by the huge rise in ocean heat, as the 2026/2027 El Niño keeps gaining in strength and as Earth's Energy Imbalance keeps increasing, as illustrated by the image below, by Leon Simons. 

The absorbed incoming solar radiation (the black line in the above image, but orange in the image below) is increasing rapidly, due to albedo loss, while outgoing longwave radiation (the red line in the above image, but black in the image below) is decreasing proportionally, due to rising concentrations of greenhouse gases. Further gases, aerosols and feedbacks can make things worse. The result is an increasingly larger amount of extra energy stored on Earth, referred to as Earth's Energy Imbalance. The image below, from an earlier post, depicts Earth energy imbalance (red in the image below) and shows where the extra energy is going (in percentages).

According to the IPCC AR6 WG1, 91% of the extra energy is taken up by oceans, 5% by land, 3% by ice melting and 1% remains in the atmosphere. Oceans, land and ice melting thus act as a buffer that did take up the vast majority (99%) of the extra energy, based on IPCC data.

More ocean heat entering the Arctic Ocean subsequently threatens to cause abrupt destabilization of sediments containing huge amounts of methane.

Pingos and conduits. Hovland et al. (2006)

Warm water can cause melting of the ice that is held in cracks and passages in sediments at the seafloor of the Arctic Ocean, allowing methane contained in the sediment to escape.

The image on the right, from a study by Hovland et al., featured in an earlier post. Hydrates can be present at the end of conduits leading to Pingos that were formed in the sediment where methane did escape from hydrates in the past. Heat can travel down such conduits relatively fast, warming up the ice in the Pingos and conduits, destabilizing hydrates and resulting in huge abrupt releases of methane from the hydrates, as well as from methane held in the form of free gas underneath such hydrates.

The huge amount of ocean heat present in the Pacific Ocean at the Equator is illustrated by the image below, adapted from NOAA, with subsurface temperature anomalies of +10.0°C at 100 m depth. 

In the Atlantic Ocean, slowing down of AMOC can cause less warm water to flow at the sea surface of the North Atlantic into the Arctic ocean. However, the rising ocean heat is not disappearing, but more heat is instead accumulating in the Atlantic Ocean. The danger is that, as more heat rises to the surface, a single cyclone may suffice to abruptly move huge parts of the accumulated ocean heat into the Arctic Ocean. Furthermore, a freshwater lid is forming at the surface of the North Atlantic, due to ocean stratification, meltwater and increased precipitation falling down the path of the Gulf Stream, facilitating warm, salty water to be carried underneath this freshwater lid into the Arctic Ocean.

The above combination image shows the situation on September 3, 2026, with Arctic sea ice concentration in the panel on the left, and sea surface temperature anomalies in the panel on the right, with a 0.6°C higher temperature than 1981-2011 highlighted at the green circle near the North Pole. 

Teleconnections: High temperatures in Tropics contributing to Antarctic sea ice decline

The image below shows ECMWF sea surface temperature anomaly forecast plumes in three El Niño regions dated September 1, 2026.

The image below shows sea surface temperatures in the El Niño 3.4 region through September 6, 2026, when the temperature was 29.62°C or 85.32°F, an anomaly of 2.96°C or 5.33°F versus 1982-2010 and a jump of 3.87°C from the 25.75°C recorded on January 9, 2026. The globe (inset bottom) shows sea surface temperature anomalies versus 1991-2020 on September 6, 2026 with the Nino3.4 region highlighted in the Pacific Ocean.

The image below shows sea surface temperatures in the Tropics through September 1, 2026, when the temperature in the Tropics was 26.23°C or 79.21°F, an anomaly of 1.3°C or 2.34°F versus 1979-2000. The globe (inset top right) shows sea surface temperature anomalies versus 1991-2020 on September 1, 2026 with the Tropics highlighted.

Sea surface temperatures are high and this contributes to Antarctic sea ice decline. Additionally, there is another mechanism contributing to the decline of Antarctic sea ice. At this time of year, the temperature can be -70°C or even lower near the South Pole and over East Antarctica, so temperature differences between the Equator and the South Pole can be very large. As a result, there can be strong wind patterns driving warm, moist air in the form of atmospheric rivers toward Antarctica, on the way taking up more moisture evaporating from the Southern Ocean. This can cause snow to fall over parts of Antarctica, thickening the snow and ice cover on Antarctica, while increasing the salt content of the Southern Ocean surface. Saltier surface waters sink more readily, allowing heat from the deep to rise, which can melt Antarctic 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 this self-amplifying feedback loop, as discussed at the Antarctica page.

Antarctic sea ice

The image below shows Antarctic sea ice concentration on September 5, 2026, by the University of Bremen (left) and the National Snow and Ice Data Center (right). Low concentration of the sea ice and of the snow and ice cover on land lowers albedo, resulting in more sunlight getting absorbed by Antarctica and by the sea ice around Antarctica.

On September 5, 2026, Antarctic sea ice area was 1.27 million km² lower than 1981-2010, the lowest on record for that day and a deviation of -3.39σ, as illustrated by the image below. The year 2026 is highlighted in black, the year 2023 is highlighted in blue and the years 2016, 2024 and 2025 are highlighted in purple.

Both 2016 and 2023 were strong El Niño years and the 2026 El Niño is on track to become even stronger. Antarctic sea ice typically reaches its annual minimum in February, but this time most sea ice may be gone earlier, as the 2026 El Niño is on track to increase in strength in the course of 2026 and become the strongest El Niño on record, which could devastate the sea ice over the coming months. 

Conclusion

The situation is dire and unacceptably dangerous, and the precautionary principle necessitates the danger to be acknowledged, while facilitating rapid, comprehensive and effective action to reduce the damage and to improve the outlook, where needed in combination with a Climate Emergency Declaration, as described in posts such as in this 2022 post and this 2025 post, and as discussed in the Climate Plan group.

Links

• Climate Reanalyzer
https://climatereanalyzer.org

• NSIDC - National Snow and Ice Data Center
https://nsidc.org/sea-ice-today

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

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

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

• NOAA - El Niño/Southern Oscillation (ENSO) diagnostic discussion - 13 August 2026

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.pdf

• ECMWF - European Centre for Medium-Range Weather Forecasts

https://charts.ecmwf.int

• Double Blue Ocean Event 2026-2027? - update June 2026
https://arctic-news.blogspot.com/2026/06/double-blue-ocean-event-2026-2027-update.html

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

• Antarctic sea ice increasingly in danger
https://arctic-news.blogspot.com/2026/08/antarctic-sea-ice-increasingly-in-danger.html

• A Tale of Two Poles
https://arctic-news.blogspot.com/p/a-tale-of-two-poles.html

• Antarctica

https://arctic-news.blogspot.com/p/antarctica.html

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

• Extreme Weather
https://arctic-news.blogspot.com/p/extreme-weather.html

• 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

Have feedbacks taken over?

For about one year now, global temperature anomalies have been extremely high, as illustrated by the image below, created with a screenshot from Copernicus, showing an anomaly from 1991-2020 of 0.86°C on June 1, 2024.

What could be behind these persistently high temperatures? Many causes such as El Niño and sunspots have been discussed in earlier posts. How much do emissions contribute to these high temperatures?

Despite pledges by politicians to ensure that temperatures would not cross 1.5°C above pre-industrial, the growth rate of the concentration of carbon dioxide in the atmosphere appears to be accelerating, as illustrated by the image below, adapted from NOAA and showing concentration of carbon dioxide at Mauna Loa, Hawaii.

Have feedbacks taken over as the dominant driver of the temperature rise? The image below shows NOAA March 2009 through May 2024 monthly CO₂ concentration at Mauna Loa (black) with a trend (magenta) added for a joint 30-year coverage. The trend shows how CO₂ could cross the clouds tipping point at 1200 ppm (parts per million) in 2038, which in itself would push up temperatures by a further 8°C.

What could cause such a steep rise? Many studies point at organic carbon and inorganic carbon releases from soils that could further raise both CO₂ concentrations and temperatures. A recent study by Weiskopf (2024) finds that biodiversity declines from climate and land use change could lead to a global loss of up to 103.14 GtC for a global sustainability scenario and up to 145.95 GtC for a fossil-fueled development scenario, indicating a self-reinforcing feedback loop where higher levels of climate change lead to greater biodiversity loss, in turn leading to greater carbon emissions. 

The clouds tipping point is actually at 1200 ppm CO₂e (carbon dioxide equivalent), so it could be crossed even earlier when also taking into account more methane, nitrous oxide, etc. As discussed in an earlier post, the daily mean CO₂ on April 26, 2024, was 428.59 ppm, while peak daily average methane is approaching 2000 parts per billion (ppb) at Mauna Loa, Hawaii. A methane concentration of 2000 ppb corresponds, at a Global Warming Potential (GWP) of 200, with 400 ppm CO₂e. Together with the daily average CO₂ concentration of 428.63 ppm this adds up to a joint CO₂e of 828.63 ppm, i.e. only 371.37 ppm away from the clouds tipping point. 

This 371.37 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 earlier posts such as this one and at the threat page.

There are many further developments and feedbacks that should be taken into account. Furthermore, note that anomalies in the image at the top are calculated from a 1991-2000 base. The temperature rise and the resulting feedbacks are even larger when anomalies are calculated from a pre-industrial base.

[ from earlier post ]

[ from Moistening Atmosphere ]

The above image, created with NASA content, shows that the February 2024 temperature was 1.76°C above 1885-1915, which could be as much as 2.75°C above pre-industrial (bright yellow inset right).

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, further accelerating the temperature rise.

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 earlier post ]

Worryingly, data for the first four months of 2024 are way higher than they were in 2023 at the same time of year, which raises fears that surface precipitable water will reach an even higher peak in 2024 than was reached in 2023. The situation is depicted even more clearly on the image below, created with the same data.

As said, more water in the atmosphere further accelerates the temperature rise. Furthermore, high relative humidity also makes high temperatures more unbearable. The human body can cool itself by sweating, which has a physiological limit that was long described as a 35°C wet-bulb temperature, i.e. 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. 

A 2022 study (by Vecellio et al., 2022) finds that the actual limit is lower — about 31°C wet-bulb or 87°F at 100% relative 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, as discussed in an earlier post. 

Temperature in either °C or °F and the relative humidity for spots on Earth can be viewed at nullschool, and then the associated wet-bulb temperature can be calculated here.

North Atlantic

There are numerous tipping points and non-linear, self-amplifying feedbacks that can all contribute, interact and start to kick in with greater ferocity, amplifying and further accelerating the rise, as discussed at the feedbacks page. 

What could push up temperatures dramatically is loss of Arctic sea ice, as discussed in earlier posts such as this one. Ominously, the North Atlantic sea surface temperature anomaly has risen strongly recently, as illustrated by the images below. 

The maps below, adapted from Climate Reanalyzer, show sea surface temperatures (left) and sea surface temperature anomalies (right) on June 2, 2024. 

North Atlantic sea surface temperatures keep rising, as illustrated by the image below that highlights temperature anomalies from 1951-1980 for May 2022, May 2023 and May 2024. 

[ click on images to enlarge ]

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

• United Nations - Adoption of the Paris Agreement (2015)

https://unfccc.int/sites/default/files/english_paris_agreement.pdf

• NOAA - Global Monitoring Laboratory - Carbon Cycle Gases, Mauna Loa, Hawaii, U.S.
https://gml.noaa.gov/dv/iadv/graph.php?code=MLO&program=ccgg&type=ts

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

• Climate Reanalyzer
https://climatereanalyzer.org

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

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

• Copernicus - Climate Pulse

https://pulse.climate.copernicus.eu

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

• Amplifying feedback loop between drought, soil desiccation cracking, and greenhouse gas emissions - by Farshid Vahedifard et al.
https://iopscience.iop.org/article/10.1088/1748-9326/ad2c23
discussed on facebook at
https://www.facebook.com/groups/arcticnews/posts/10161298567849679

• Size, distribution, and vulnerability of the global soil inorganic carbon - by Yuanyuan Huang et al. https://www.science.org/doi/10.1126/science.adi7918
discussed at facebook at
https://www.facebook.com/groups/arcticnews/posts/10161354439024679

• Biodiversity loss reduces global terrestrial carbon storage - by Sarah Weiskopf et al. (2024)  https://www.nature.com/articles/s41467-024-47872-7

Discussed at Facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10161454674974679

• Very high temperatures in Tropics
https://arctic-news.blogshttps://arctic-news.blogspot.com/2023/07/wet-bulb-globe-temperature-tipping-point.htmlpot.com/2024/05/very-high-temperatures-in-tropics.html

• Extreme heat stress
https://arctic-news.blogspot.com/2023/06/extreme-heat-stress.html

• Wet Bulb Globe Temperature Tipping Point

https://arctic-news.blogspot.com/2023/07/wet-bulb-globe-temperature-tipping-point.html

• 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

• Temperature rise may soon accelerate even more
https://arctic-news.blogspot.com/2024/05/temperature-rise-may-soon-accelerate-even-more.html

• nullschool

https://earth.nullschool.net

• wet bulb temperature calculator

https://www.mit.edu/~eltahirgroup/calTW.html

• Convert the temperature between Celsius and Fahrenheit

https://www.convert-me.com/en/convert/temperature/?u=dcelsius&v=40

• Feebacks in the Arctic
https://arctic-news.blogspot.com/p/feedbacks.html

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

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

• Arctic Ocean Feedbacks
https://arctic-news.blogspot.com/2017/01/arctic-ocean-feedbacks.html

• Arctic sea ice set for steep decline
https://arctic-news.blogspot.com/2024/03/arctic-sea-ice-set-for-steep-decline.html

• 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

  

Dangerous situation in Arctic

In the North Pacific, the flow of warmer water is clearly visible (see images right, green circle left).

In the North Atlantic, huge amounts of heat are moving into the Arctic Ocean (green circle right).

At some spots, heat that is traveling underneath the sea surface comes to the surface (green circle at the top).

Most warming caused by people's emissions goes into oceans, especially into the top layer of oceans.

Furthermore, warmer air and warmer sea surfaces can cause winds to grow dramatically stronger. As the Arctic is warming much faster than the rest of the world, the narrowing difference between the temperatures at the North Pole and the Equator is decreasing the speed at which winds circumnavigate Earth; at the same time, the amount of heat that is moving north can grow dramatically, both due to winds and sea currents, and cyclones can further accelerate this.

The danger is that an influx of warm salty water will reach the seafloor and trigger methane eruptions.

The situation is especially critical in many parts of the Arctic Ocean where the water is very shallow. Some 75% of the East Siberian Arctic Shelf (ESAS) is shallower than 50 m (see maps on the right).

[ warm water from the Atlantic Ocean is
increasingly invading the Arctic Ocean ]

The danger here is huge, for numerous reasons, incl.:

• shallow waters can warm up very rapidly in case of an influx of warm water;

• these shallow seas are now covered by ice, so the heat cannot escape to the atmosphere;

• sea ice is very thin, so the sea ice won't act as a buffer to absorb the heat;

• methane rising through shallow waters will pass through the water column and enter the atmosphere more quickly;

• in shallow waters, large abrupt releases will more quickly deplete the oxygen in the water, making it harder for microbes to break down the methane;

• hydroxyl levels over the Arctic are very low, which means that it takes much longer for methane over the Arctic to get broken down.

The four videos below provide a good introduction into the various issues and illustrate how dangerous the situation is in the Arctic.

Each video is part of a talk between Dave Borlace and Peter Wadhams.

Part 1 discusses albedo change in the Arctic and associated changes such as jet stream changes.

Part 2 discusses the threat of huge methane releases in the Arctic.

Part 3 discusses the thermohaline circulation and methods that could improve the situation such as carbon removal and Ocean Mechanical thermal Energy Conversion (OMTEC).

Part 4 discusses sea level rise and fires.

The situation is dire and calls for comprehensive and effective action, as described at the Climate Plan, i.e. multiple lines of action implemented in parallel and locally where possible.


Links

• As El Niño sets in, will global biodiversity collapse in 2019?
https://arctic-news.blogspot.com/2018/11/as-el-nino-sets-in-will-global-biodiversity-collapse-in-2019.html

• Doomsday by 2021?
https://arctic-news.blogspot.com/2018/11/doomsday-by-2021.html

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

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

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

• Seismic Events
https://arctic-news.blogspot.com/p/seismic-events.html

• Can we weather the Danger Zone?
https://arctic-news.blogspot.com/2018/07/can-we-weather-the-danger-zone.html

• How much warmer is it now?
https://arctic-news.blogspot.com/2018/04/how-much-warmer-is-it-now.html

• What Does Runaway Warming Look Like?
https://arctic-news.blogspot.com/2018/10/what-does-runaway-warming-look-like.html

• Peaks Matter
https://arctic-news.blogspot.com/2018/08/peaks-matter.html

• Warning of mass extinction of species, including humans, within one decade
https://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html

Will August 2018 be the hottest month on record?

July and August are typically about 3.6ºC or 6.5ºF warmer than December and January. August is typically 1.8°C or 3.24ºF warmer than the average annual temperature. Above image shows how much higher the temperature was for selected months, compared to the annual global mean for the period 1980-2015. Will August 2018 be the hottest month on record?

Numerous temperature records have fallen across the world recently. Heat stress hazard is high under conditions of high surface air temperature and high relative humidity. When looking at heat stress hazards, it's therefore important to look at surface air temperatures over land, i.e. the temperature of the air above the land surface.

Fire hazard is high under conditions of hot and dry soil and strong wind. When looking at fire hazards, it's therefore important to look at land surface temperatures, reflecting how hot the surface of the Earth would feel to touch in a particular location. The map below shows land surface temperatures.

When calculating how much warmer it is now, a number of things must be taken into account:

1. Baseline
   
   What baseline is used and how is the temperature at the baseline calculated? In the image at the top, the baseline is 1980-2015, which is a very recent period. When using a preindustrial baseline, anomalies could be more than 0.6°C higher than when using the 1951-1980 baseline that NASA normally uses.
   
   
2. Surface temperatures or surface air temperatures?
   
   Above map shows land surface temperatures. As said above, this is different from surface air temperatures over land that show the temperature of the air above the land surface.
   
   Similarly, sea surface temperatures indicate the temperature of the water at the surface. Sea surface air temperatures, on the other hand, are slightly higher, they are measurements of the air temperature just above the surface of the water.
   
   NASA typically uses surface air temperatures over land, while using surface water temperatures over oceans. When instead using air temperatures globally, the temperature anomaly could be more than 0.1°C higher.
    
3. Missing data
   
   How are missing data dealt with? To calculate the global mean on maps, NASA uses four zonal regions (90-24ºS, 24-0ºS, 0-24ºN, and 24-90ºN) and fills gaps in a region by the mean over the available data in that region. In datasets, however, missing data are typically ignored. This could make a difference of 0.2°C. Ignoring data for the Arctic alone could make a difference of 0.1°C.  

Depending on how the above three points are dealt with, the temperature in August 2018 may well be more than 3°C above the mean annual global temperature in 1750. The question is whether August 2018 will be warmer than August 2016, which was 2.3°C warmer than 1980-2015.

Anthropogenic Global Warming

Remember the Paris Agreement, when politicians pledged to take efforts to ensure that the temperature would not cross 1.5°C above pre-industrial? Why did the Paris Agreement not specify a year for pre-industrial? Perhaps the idea was that total anthropogenic global warming should not exceed 1.5°C. In other words, the warming that people had already caused by 1750, plus the warming people caused since 1750, plus the warming that is already baked in for the decades to come. The image below illustrates this idea and also shows that we're well above 1.5°C anthropogenic global warming.

In the image below, temperatures have also been adjusted to better reflect a preindustrial baseline (1750), showing that temperatures were not higher than 1°C above pre-industrial during the entire Holocene, until recently.

In a recent paper, James Hansen et al. conclude that temperatures also weren't more than 1°C above pre-industrial during the previous interglacial, the Eemian, which implies that temperatures haven't been more than 1°C above pre-industrial for the entire 200,000 years that modern people, i.e. the species homo sapiens, have existed, and that temperatures have only recently rising to levels more than 1°C above pre-industrial. Quite likely, to find temperatures as high as today's, one would have to go back some 3 million years.

Fires over North America, August 2018

Fires can significantly influence temperatures in a number of ways. The images below show how fires boosted carbon dioxide, carbon monoxide and sulfur dioxide levels on August 19, 2018. Carbon dioxide and carbon monoxide both raise temperatures. On the other hand, sulfur dioxide lowers temperature by reflecting sunlight back into space.

Top left: carbon monoxide as high as 51495 ppb Top right: carbon dioxide as high as 836 ppm Bottom left: Smoke over North America Bottom right: sulfur dioxide as high as 1917.57 µg/m³

The image below illustrates to what extent smoke from fires boosted black carbon in the air over North America on August 23, 2018. Black carbon causes both cooling and warming. Black carbon shades the surface, somewhat cooling the surface of land and water, while it also absorbs heat, thus warming the air above the surface. Furthermore, black carbon causes warming by darkening the surface once it settles down. Studies have calculated that black carbon has a total net global warming effect of more than 1.1 W/m².

Dust and further aerosols

The impact of aerosols such as sulfur dioxide and dust is often overlooked. The image below shows that τ, i.e. light at 550 nm as a measurement of aerosol optical thickness due to dust aerosols, was as high as 4.0641 on June 16, 2018.

[ goats, from Wikipedia ]

Dust is one reason why temperatures didn't cross the 1°C above pre-industrial mark during the peak of the recent Milankovitch cycle. A recent study calculates that the global annual mean surface temperature increases by 0.3°C for the mid-Holocene (6 ka), if the dust is completely removed.

Most dust appears to originate from the Sahara Desert, which lost its vegetation during the Holocene due to goats, according to this study, as people removed predators such as lions and tigers. As the Sahara lost its vegetation, the surface became more reflective, while dust further made that temperatures didn't rise as much as they otherwise would have.

Deforestation has caused a lot of carbon dioxide to be added during pre-industrial times, and there is also the impact of black carbon aerosols, resulting from biomass and fossil fuel burning, which causes some 1.1W/m² warming today and some 0.2W/m² is coming from pre-industrial activities.

In conclusion, temperatures would be a lot lower in the absence of human activities, while total anthropogenic global warming over the past few thousand years is much larger than most people think.

The situation is dire and calls for comprehensive and effective action, as described in the Climate Plan.


Links

• NASA - The Northwest is Running Hot and Dry
https://earthobservatory.nasa.gov/images/92601/the-northwest-is-running-hot-and-dry

• NASA GISS (Goddard Institute for Space Studies) Surface Temperature Analysis (GISTEMP)
https://data.giss.nasa.gov/gistemp

• NASA - Just Another Day on Aerosol Earth
https://earthobservatory.nasa.gov/images/92654/just-another-day-on-aerosol-earth

• Aerosols
https://arctic-news.blogspot.com/p/aerosols.html

• How much warming have humans caused?
https://arctic-news.blogspot.com/2016/05/how-much-warming-have-humans-caused.html

• How much warmer is it now?
https://arctic-news.blogspot.com/2018/04/how-much-warmer-is-it-now.html

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

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

A Global Temperature Rise Of More than Ten Degrees Celsius By 2026?

How much have temperatures risen and how much additional warming could eventuate over the next decade? The image on the right shows a potential global temperature rise by 2026 from pre-industrial levels. This rise contains a number of elements, as discussed below from the top down.

February 2016 rise from 1900 (1.62°C)

The magenta element at the top reflects the temperature rise since 1900. In February 2016, it was 1.62°C warmer compared to the year 1900, so that's a rise that has already manifested itself.

Rise from pre-industrial levels to 1900 (0.3°C)

Additional warming was caused by humans before 1900. Accordingly, the next (light blue) element from the top down uses 0.3°C warming to reflect anthropogenic warming from pre-industrial levels to the year 1900.

When also taking this warming into account, then it was 1.92°C (3.46°F) warmer in February 2016 than in pre-industrial times, as is also illustrated on the image below.

Warming from the other elements (described below) comes on top of the warming that was already achieved in February 2016.

Rise due to carbon dioxide from 2016 to 2026 (0.5°C)

The purple element reflects warming due to the amount of carbon dioxide in the atmosphere by 2026. While the IEA reported that energy-related carbon dioxide emissions had not risen over the past few years, carbon dioxide levels in the atmosphere have continued to rise, due to feedbacks that are kicking in, such as wildfires and reduced carbon sinks. Furthermore, maximum warming occurs about one decade after a carbon dioxide emission, so the full warming wrath of the carbon dioxide emissions over the past ten years is still to come. In conclusion, an extra 0.5°C warming by 2026 seems possible as long as carbon dioxide levels in the atmosphere and oceans remain high and as temperatures keep rising.

Removal of aerosols masking effect (2.5°C)

With dramatic cuts in emissions, there will also be a dramatic fall in aerosols that currently mask the full warming of greenhouse gases. From 1850 to 2010, anthropogenic aerosols brought about a decrease of ∼2.53 K, says a recent paper. While on the one hand not all of the aerosols masking effect may be removed over the next ten years, there now are a lot more aerosols than in 2010. A 2.5°C warming due to removal of part of the aerosols masking effect therefore seems well possible by the year 2026.

Albedo changes in the Arctic (1.6°C) 

Warming due to Arctic snow and ice loss may well exceed 2 W per square meter, i.e. it could more than double the net warming now caused by all emissions by people of the world, calculated Professor Peter Wadhams in 2012. A 1.6°C warming due to albedo changes (i.e. decline of both Arctic sea ice and snow and ice cover on land) therefore seems well possible by the year 2026.

Methane eruptions from the seafloor (1.1°C)

". . we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time," Dr. Natalia Shakhova et al. wrote in a paper presented at EGU General Assembly 2008. Authors found that such a release would cause 1.3°C warming by 2100. Note that such warming from an extra 50 Gt of methane seems conservative when considering that there now is only some 5 Gt of methane in the atmosphere, and over a period of ten years this 5 Gt is already responsible for more warming than all the carbon dioxide emitted by people since the start of the industrial revolution. Professor Peter Wadhams co-authored a study that calculated that methane release from the seafloor of the Arctic Ocean could yield 0.6°C warming of the planet in 5 years (see video at earlier post). In conclusion, as temperatures keep rising, a 1.1°C warming due to methane releases from clathrates at the seafloor of the world's oceans seems well possible by the year 2026.

Extra water vapor feedback (2.1°C)

Rising temperatures will result in more water vapor in the atmosphere (7% more water vapor for every 1°C warming), further amplifying warming, since water vapor is a potent greenhouse gas. Extra water vapor will result from warming due to the above-mentioned albedo changes in the Arctic and methane releases from the seafloor that could strike within years and could result in huge warming in addition to the warming that is already there now. As the IPCC says: "Water vapour feedback acting alone approximately doubles the warming from what it would be for fixed water vapour. Furthermore, water vapour feedback acts to amplify other feedbacks in models, such as cloud feedback and ice albedo feedback. If cloud feedback is strongly positive, the water vapour feedback can lead to 3.5 times as much warming as would be the case if water vapour concentration were held fixed", according to the IPCC. Given a possible additional warming of 2.7°C due to just two elements, i.e. Arctic albedo changes and seafloor methane, an additional warming over the next decade of 2.1°C due to extra water vapor in the atmosphere therefore does seem well possible by the year 2026.

Further feedbacks (0.3°C)

Further feedbacks will result from interactions between the above elements. Additional water vapor in the atmosphere and extra energy trapped in the atmosphere will result in more intense storms and precipitation, flooding and lightning. Flooding can cause rapid decomposition of vegetation, resulting in strong methane releases. Furthermore, plumes above the anvils of severe storms can bring water vapor up into the stratosphere, contributing to the formation of cirrus clouds that trap a lot of heat that would otherwise be radiated away, from Earth into space. The number of lightning strikes can be expected to increase by about 12% for every 1°C of rise in global average air temperature. At 3-8 miles height, during the summer months, lightning activity increases NOx by as much as 90% and ozone by more than 30%. The combination of higher temperatures and more lightning will also cause more wildfires, resulting in emissions such as of methane and carbon monoxide. Ozone acts as a direct greenhouse gas, while ozone and carbon monoxide can both act to extend the lifetime of methane. Such feedbacks may well result in an additional 0.3°C warming by the year 2026.

Total potential global temperature rise by 2026 (10°C or 18°F)

Adding up all the warming associated with the above elements results in a total potential global temperature rise (land and ocean) of more than than 10°C or 18°F within a decade, i.e. by 2026. As said before, this scenario assumes that no geoengineering will take place over the next decade.

The situation is dire and calls for comprehensive and effective action as described in the Climate Plan.