Arctic News

Monday, June 1, 2026

Carbon dioxide highest in millions of years - update 2

SSP5-8.5 scenario

The above image shows IPCC projections for CO₂ concentration and temperature change for the SSP5-8.5 scenario. The IPCC translates concentrations of greenhouse gases into radiative forcing (see image below), which can in turn be converted into temperature change (see image above) by using a climate sensitivity multiplier.

In the SSP5-8.5 scenario, radiative forcing is by definition projected to increase to 8.5 W/m² by 2100. When using an (older) climate sensitivity multiplier of 0.75, this could result in a temperature rise of more than 6°C by 2100. Recent research such as by James Hansen et al. suggests that a higher climate sensitivity multiplier should be used, which could result in a temperature rise of more than 10°C by 2100 in the SSP5-8.5 scenario.

The IPCC has a history of trying to downplay the strength of global warming and refuses to accept that its projections have been too low. Lo and behold, some scientist have now come forward to accommodate the IPCC by suggesting to drop SSP5-8.5 altogether, arguing it had become "implausible, based on trends in the costs of renewables, the emergence of climate policy and recent emission trends".

Let's take a look into those arguments. While the cost of renewables and sales of coal have fallen, the emergence of climate policy depends on political opinion. The temperature rise is accelerating and feedbacks are threatening to kick in with greater ferocity. The rise in the Earth Energy Imbalance and in ocean heat is outpacing SPSS5-8.5, as discussed in an earlier post. Furthermore, the aerosol masking effect is decreasing. Additionally, IPCC models subtract assumed carbon dioxide removal (CDR), despite doubts regarding the way the IPCC seeks CDR to take place, as discussed in this post and in this video posted on facebook.

Therefore, it is vital to include SSP5-8.5 as a reference, in order to inform and warn about a potentially huge temperature rise, the more so since mainstream media fail to do so and policymakers typically look only a few years ahead. Indeed, not including warnings could be a recipe for bad climate policy, halting or even reversing the necessary climate action.

Now let's take another look into some recent measurements of greenhouse gas concentrations.

Carbon dioxide (CO₂)

The image below, from an earlier post, shows the CO₂ concentration over 31 days at Mauna Loa, Hawaii. The hand points at a daily CO₂ concentration of 433.95 parts per million (ppm) recorded on May 1, 2026.

The image below, dated June 1, 2026, shows carbon dioxide concentration over the past few years at Mauna Loa, Hawaii. Note the high surface flask measurements recorded recently.

The image below shows daily carbon dioxide at Utqiaġvik, formerly know as Barrow, Alaska, June 1, 2026.

Nitrous oxide (N₂O)

The image below shows nitrous oxide concentration at Mauna Loa, Hawaii, June 1, 2026.

The image below shows monthly nitrous oxide at Utqiaġvik, formerly know as Barrow, Alaska, June 1, 2026.

Nitrous oxide has a lifetime of 109 years and a Global Warming Potential (GWP) of 273 for a horizon of 20 years and also a GWP of 273 over 100 years, according to IPCC AR6. Nitrous oxide is both a potent greenhouse gas and a compound that depletes ozone in the ozone layer.

The image below shows the globally averaged marine surface mean nitrous oxide concentration through 2025 with a trend added to show the potential for a huge rise by 2047.

Methane (CH₄)

The image below shows monthly methane at Mauna Loa, Hawaii, June 1, 2026.

[ from earlier post, discussed on facebook ]

Greenhouse gas concentrations are rising and carbon dioxide and nitrous oxide are rising fast, while methane is rising even faster (see image on the right) and more methane threatens to erupt from the seafloor, as discussed in earlier posts such as this one and this one.

There are many feedbacks that further contribute to the temperature rise (such as albedo loss and more heat moving remaining in the atmosphere instead of being absorbed by oceans, ice and land, as discussed below). Altogether, this could result in a temperature rise of more than 20°C within one year, as discussed in an earlier post.

Sulfur hexafluoride (SF₆)

The image below shows a worrying recent rise in concentrations of sulfur hexafluoride (SF₆), which has a global warming potential (GWP) over 100 years of 24,300 and, because it has a lifetime of 1000 years, its GWP over 500 years is even higher, i.e. 29,000 (IPCC AR6).

Regarding SF₆, one does not have to bother to check historical levels, since the vast majority of SF₆ in the atmosphere is produced by people, it's a synthetic, industrial gas that leaked from its use mainly as an insulator in high-voltage and medium-voltage power systems and lines that can carry power over long distances. Clearly, too little is done politically to reduce SF₆ emissions, even though there are safe, viable alternatives available to using SF₆ in the power industry. Furthermore, rooftop solar systems can - where needed - be part of microgrids, which can reduce the need for transmission lines, poles and towers, so microgrids can also reduce fire hazards. Fire can also destroy warehouses where SF₆ is stored in tanks.

For high concentrations of surfur hexafluoride recorded at other locations, also see this post and comments at facebook.

The image below shows global annual mean SF₆ through 2025, with a trend added to show the potential for a huge rise by 2037.

This is an update of an earlier post that also discusses the Earth Energy Imbalance and the threat of a rapid rise in methane in more detail.

Conclusion

The situation is dire and unacceptably dangerous, and the precautionary principle necessitates 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

• NOAA - Global Monitoring Laboratory - data viewer
https://gml.noaa.gov/dv/iadv

• NOAA - Global Monitoring Laboratory - Carbon Cycle Greenhouse Gases - Mauna Loa, Hawaii
https://gml.noaa.gov/ccgg/trends/mlo.html

• NOAA - Office of Satellite and Products Operations - NOAA-20 and NOAA-21 satellites
https://www.ospo.noaa.gov/products/atmosphere/soundings/heap/nucaps/new/nucaps_products.html

• IPCC AR6, Workgroup 1, Chapter 4, Future Global Climate: Scenario-based Projections and Near-term Information
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter04.pdf

• IPCC AR6, Workgroup 1, Chapter 7, Supplementary material - SF6 GWP and lifetime
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter07_SM.pdf

• 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

Thursday, May 21, 2026

Ocean heat threatens sea ice

Sea surface temperatures and El Niño

The upcoming El Niño threatens to contribute to loss of virtually all Arctic sea ice in September 2026, which would in turn result in albedo loss, transfer of ocean heat to the atmosphere and additional emissions that could jointly increase the global temperature dramatically and could subsequently also cause virtually all Antarctic sea to disappear a few months later.

Forecasts indicate that the upcoming El Niño threatens to become a monster within a few months time.

The above image, adapted from NOAA, shows a sea surface temperature anomaly forecast update for June 1, 2026, for the Niño3.4 region (which is indicative for El Niño development). Forecasts exceed 4°C for part of some forecast members and exceed 3.5°C for part of the forecast for the Coupled Forecast System version 2 (CFS.v2) ensemble mean (black dashed line).

The image below shows a sea surface temperature anomaly forecast update for June 1, 2026, for the Niño3 region, with forecasts exceeding 4°C for parts of some forecast members and approaching 4°C for part of the mean.

Forecasts of sea surface temperature anomalies in El Niño regions this high indicate that the 2026-2027 El Niño will be even stronger than the 2015-16 El Niño, as illustrated by the image below, adapted from Climate Reanalyzer and with a potential 2026 El Niño anomaly of 3.5°C added (red dashed line on the right).

[ from earlier post, click on images to enlarge ]

High sea surface temperatures were recorded in the Pacific Ocean on May 22, 2026.

The above image highlights sea surface temperature anomalies from 1981–2011 on May 22, 2026, in three areas: 5.3°C off the coast of South America, 4.6°C off the coast of California and 5.4°C off the coast of Asia.

The image below highlights sea surface temperature anomalies from 1981–2011 on May 29, 2026, in four areas: 7.2°C off the coast of France, 8.1°C off the coast of Asia, 5.3°C off the coast of South America, and 6.3°C off the coast of South Africa.

As illustrated by the image below, adapted from NOAA, a huge amount of subsurface ocean heat has accumulated in the last two months across most of the equatorial Pacific Ocean.

The image below shows that on May 21, 2026, the sea surface temperature (SST) was the highest on record for this time of year in the Niño3.4 region (5°S–5°N, 120–170°W, inset), an area in the Pacific Ocean that is indicative for development of El Niño.

Forecasts of sea surface temperature anomalies in El Niño regions partly exceeding 3.5°C indicate that the 2026-2027 El Niño will be even stronger than the 2015-16 El Niño and will be the strongest El Niño on record, as discussed in an earlier post.

On May 23, 2026, the world (60°S–60°N, 0–360°E, inset also shows anomalies) sea surface temperature was the highest on record for this time of year, as illustrated by the image below.

Sea surface temperatures (SST) peak twice each year: in March/April (when it's Summer in the Southern Hemisphere) and in August (when it's Summer in the Northern Hemisphere). There were La Niña conditions in early 2026, yet 2026 SST were close to and at times exceeded the record high SST reached in 2024, which was an El Niño year. The remainder of 2026 is likely to be dominated by El Niño conditions. According to NOAA, there is 82% chance of an El Niño in May-July 2026 and 96% chance that El Niño will continue through Northern Hemisphere winter 2026-27.

The inset shows sea surface temperature anomalies for the entire globe on May 23, 2026. A larger version is added below.

[ click on images to enlarge ]

A temperature of 52.1°C or 125.7°F is forecast in Pakistan on May 28, 2026, at the location marked by the green circle.

SSP5-8.5 scenario

In the SSP5-8.5 scenario, radiative forcing is projected to increase to 8.5 W/m² by 2100. Below are the IPCC projections for CO₂ concentration and temperature change for the SSP5-8.5 scenario.

The image below shows the CO₂ concentration over the last 31 days at Mauna Loa, Hawaii. The hand points at a daily CO₂ concentration of 433.95 parts per million (ppm) recorded on May 1, 2026.

Ocean heat threatens sea ice

Rising temperatures are threatening to cause dramatic loss in sea ice. Both subsurface ocean heat and ocean heat that has moved from the ocean to the atmosphere during the upcoming El Niño can be expected to contribute to strong loss of Arctic sea ice over the next few months.

The rise in the Earth Energy Imbalance and in ocean heat is outpacing SPSS5-8.5, as illustrated by the combination image below, by Leon Simons.

As illustrated by the image below, Arctic sea ice extent was 11.61 million km² on May 28, 2026 (black), 2nd lowest on record for the time of year and a deviation from 1981-2010 of -2.91σ. Highlighted in blue is the sea ice extent in 2012 (record low year) and highlighted in purple is the sea ice extent in 2016, when there was a strong El Niño.

The image below, adapted from the Danish Meteorological Institute, shows that the daily Arctic sea ice volume was at a record low for the time of year on May 31, 2026, as it has been for years.

As illustrated by the image below, global sea ice area was 1.69 million km² lower than 1981-2010 on May 21, 2026, the lowest global area on record for the time of year and a deviation from 1981-2010 of -3.77σ. Highlighted in black is 2026 and highlighted in blue is 2025, until now the record low year for global sea ice area.

The map below shows an update of an earlier forecast for November 2026 with temperature anomalies over most of the Arctic Ocean at the top of the scale (13°C), adapted from tropicaltidbits.com.

These high temperatures over the Arctic Ocean suggests strong sea ice decline, with the danger that huge amounts of greenhouse gases including methane will be released from the seafloor of the Arctic Ocean and from thawing terrestrial permafrost, coming with huge albedo changes and loss of the latent heat buffer, further accelerating the temperature rise. There are further developments that can contribute to a rapid and potentially huge temperature rise. The potential rise in methane and its impact are discussed in this earlier post.

The map above, from an earlier post, and the map below show forecasts for December 2026 and January 2027, respectively, with temperature anomalies over parts of the Arctic Ocean exceeding 10°C, based on SSP5-8.5 or what used to be called the "worst-case scenario".

Ominously, the forecast for January 2027 below, from an earlier post and adapted from tropicaltidbits.com, shows very high sea surface temperatures anomalies around Antarctica, which spells bad news for Antarctic sea ice, which typically reaches its annual minimum in February.

Is SSP5-8.5 the "worst-case" scenario?

The image below, adapted from ClimateReanalyzer, shows the Coupled Model Intercomparison Project Phase 6 (CMIP6) for the SSP5-8.5 scenario pointing at a temperature rise of 1.661°C in February 2025, of 4.388°C in February 2083 and of 5.163°C in February 2100, when using a 1901-2000 base (temperatures will be higher when a genuinely pre-industrial base is used).

The map below, from an earlier post, shows the CMIP6 SSP5-8.5 rise versus 1881-1920 in February 2100. The map shows that the temperature rise in areas on land (where most people live) could be as much as 8°C higher in Feb 2100 in the SSP585 model.

The map warns that temperatures over large parts of the Arctic may be more than 20°C higher than 1881-1920 in February 2100. This would suggest that by 2100 the snow and ice cover in the Arctic will have declined dramatically and that huge amounts of greenhouse gases will likely have been released from the seafloor of the Arctic Ocean and from thawing terrestrial permafrost, with huge albedo changes as well as loss of the latent heat buffer, further accelerating the temperature rise over the years.

The CMIP6 emission levels (quantified by SSP5-8.5) did not fully include the potential impact of bad climate policy and of feedbacks such as seafloor methane eruptions and loss of lower clouds. For "even-worse-than-SSP5-8.5" scenarios, have a look at the potential for a global temperature rise of more than 20°C by 2050 discussed in this 2013 post and the potential for a 18.44°C rise by the end of 2026 discussed in this recent post.

The immensity of the danger justifies keeping a close and watchful eye on the data, on research, on forecasts and projections, e.g. data from Copernicus' Methane Hotspot Explorer shows that the largest methane emission event in October 2024 occurred from an urban landfill in Kazakhstan, while the top seven methane emission events included landfills, oil and coal, but not natural gas operations, as illustrated by the image below.

Temperatures have risen due to human activities over thousands of years. Over the years, the focus of these activities has shifted four times and a fifth shift is coming up.
1. Moving away from hunting and gathering toward herding animals and agriculture.
2. Moving to cities, where people found work in factories (the Industrial Revolution).

3. Rising urban services and infrastructure, commuters to and from sprawling suburbs.
4. Avoiding damaging the climate and environment, with a focus on electrifying energy.

5. A focus on transforming society through renewal of cities, land use and infrastructure.

The fourth shift is highlighted by the UN's adoption of a resolution that calls on all UN Member States to take all possible steps to avoid causing significant damage to the climate and environment, including emissions produced within their borders, and to follow through on their existing climate pledges under the Paris Agreement. This sends a strong message that tackling the climate crisis is a legal duty under international law, and not just a political choice. The resolution also calls for the UN Secretary-General to submit a report in 2027 on ways to advance compliance with the obligations identified in the International Court of Justice advisory opinion.

The Climate Plan group discusses the fifth shift, i.e transforming society while highlighting the importance of a formal declaration of a climate emergency to raise awareness and to help overcome obstacles that could delay the necessary climate action, with a climate emergency declared globally and with implementation of climate action preferably decided locally provided it is in line with best-available science.

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

• NOAA - Seasonal climate forecast from CFSv2
https://www.cpc.ncep.noaa.gov/products/CFSv2/CFSv2_body.html

• nullschool.net

https://earth.nullschool.net

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

• NOAA - El Niño/Southern Oscillation (ENSO) Diagnostic discussion, Climate Prediction Center, National Center for Environmental Prediction, statement issued 14 May 2026

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

• Climate Reanalyzer
https://climatereanalyzer.org

• NOAA - Global Monitoring Laboratory - Carbon Cycle Greenhouse Gases - Mauna Loa, Hawaii
https://gml.noaa.gov/ccgg/trends/mlo.html

• IPCC Assessment Report 6 Workgroup 1 Chapter 4 - Future Global Climate: Scenario-based Projections and Near-term Information
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter04.pdf

• NSIDC - National Snow and Ice Data Center, a part of CIRES at the University of Colorado Boulder
https://nsidc.org/sea-ice-today/sea-ice-tools/charctic-interactive-sea-ice-graph

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

• Kevin Pluck - sea ice visuals
https://seaice.visuals.earth

• Tropicaltidbits.com
https://www.tropicaltidbits.com

• Leon Simons - rise in ocean heat and Earth Energy Imbalance
https://bsky.app/profile/leonsimons.com/post/3mloc6c4bas2v

• 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

Friday, May 15, 2026

Northern Hemisphere heating up

The global surface air temperature was 15.91°C on May 13, 2026, the highest temperature on record for the time of year and 0.72°C higher than 1991-2020 (more from pre-industrial), as illustrated by the image below, adapted from Copernicus.

The image below also shows the temperature through May 13, 2026, while showing a 0.74°C anomaly from 1991-2020 and a 1.01°C anomaly from 1979-2000 (and even more from a pre-industrial base).

The Northern Hemisphere temperature was 17.56°C on May 9, 2026, the highest temperature on record for the time of year and 1.17°C higher than 1979-2000 (and even more from pre-industrial).

The Northern Hemisphere is now heating up rapidly:
• Seasonal change - temperatures typically reach a peak in July

• The Northern Hemisphere has more land, where temperatures reach higher levels in Summer

• The temperature rise is accelerating with feedbacks kicking in with greater ferocity
• We're rapidly moving from a La Niña into an El Niño

El Niño is discussed in this earlier post and illustrated by the image below, adapted from NOAA.

[ from earlier post ]

Greenhouse gas concentrations

A recent surface flask reading shows carbon dioxide concentration approaching 437.5 parts per million (ppm) at Mauna Loa, Hawaii, as illustrated by the image below, dated May 17, 2026.

Another reading dated May 17, 2026, shows the monthly average carbon dioxide concentration exceeding 432.5 ppm at Mauna Loa, Hawaii.

Accelerating temperature rise

The image below, from an earlier post, illustrates a potentially strongly accelerating temperature rise on land in the Northern Hemisphere in the course of 2026. Note that the anomalies in the image below are from 1901-2000 and would be higher when calculated from pre-industrial.

[ from earlier post ]

The image below uses Global Land+Ocean NASA monthly data through March 2026. Data are first adjusted from NASA's default 1951-1980 base to an earlier 30-year base, i.e. a 1886-1915 base, and then further adjusted by 0.99°C to reflect ocean air temperatures, higher polar anomalies and a pre-industral base.

[ from earlier post ]

How the 0.99°C adjustment in the above image is calculated is shown in the bright yellow inset of the image below, from an earlier post and discussed at the pre-industrial page.

[ from April 2024 post, click on images to enlarge ]

The map below shows a forecast for December 2026 with temperature anomalies in parts of the Arctic exceeding 10°C in December 2026 for the SSP5-8.5 model. This suggests strong decline of the snow and ice cover in the Arctic with the danger that huge amounts of greenhouse gases including methane will be released from the seafloor of the Arctic Ocean and from thawing terrestrial permafrost, with huge albedo changes as well as loss of the latent heat buffer, further accelerating the temperature rise over the years. There are further contributors to a rapid and potentially huge temperature rise. The potential rise in methane and its impact are discussed in this earlier post, while SSP5-8.5 was discussed in this earlier post.

Some suggest that the IPCC should no longer consider the SSP5-8.5 model, because it had become "implausible, based on trends in the costs of renewables, the emergence of climate policy and recent emission trends". However, the 8.5 refers to a radiative forcing of 8.5 W/m² by 2100. While the cost of renewables and sales of coal have fallen, the temperature rise is accelerating and feedbacks are threatening to kick in with greater ferocity. Furthermore, the aerosol masking effect is decreasing. Additionally, as also discussed in this post and in this video posted on facebook, models subtract assumed carbon dioxide removal (CDR), despite doubts that CDR can be accomplished in the way the IPCC is suggesting. This is one of the reasons why models hang on to projections by 2100, i.e. models insist on including doubtful promises of CDR (especially after 2050) in an effort to calculate a lower temperature average for the century, in the process waving away the danger of a huge temperature rise occurring soon. Instead, it is vital to include warnings about a potentially huge temperature rise in advice to policymakers, the more so since policymakers typically look only a few years ahead.

The image below, from an earlier post, shows a temperature anomaly forecast for December 2026, with very high anomalies again showing up over most of the Arctic Ocean.