Arctic News: Huge temperature rise in 2026?

Monday, December 29, 2025

Huge temperature rise in 2026?

[ see the Extinction page ]

A huge temperature rise threatens to unfold and it could do so as early as next year, as illustrated by the image on the right. Altogether, the rise from pre-industrial to 2026 could be more than 18.44°C by 2026.

The image conceptually dates back to 2016, when a strong El Nino came with a temperature rise that, when expressed by means of a polynomial trend that was extended by a decade pointed at a 10°C rise by 2026.

The barchart on the right has basically remained the same over the past ten years, be it that the historic temperature rise from pre-industrial has turned out to be larger (pink) and that the cloud feedback could add a further 8°C to the rise (grey). Also, aerosols have been split up into on the one hand sulfates (green) and on the other hand carbon monoxide, black & brown carbon and non-methane volatile organic carbon (brown).

Importantly, posts have over time pointed out that humans are likely to go extinct with a rise of 3°C and most life on Earth will disappear with a 5°C rise, as illustrated by the image below, from an analysis discussed in an earlier post.

With the year 2026 approaching fast, it is time to have another look at how fast and by how much temperatures could rise.

The image below shows how, over the course of one year, temperature anomalies in 2023, 2024 and 2025 each have at times reached the highest daily records. The image shows temperature anomalies (vs 1991-2020) from 1940 through to December 26, 2025.

The image below, from an earlier post, shows NASA Land Only monthly temperature anomalies (black squares) with respect to 1880-1890 (not pre-industrial) through November 2025 and shows the 1.5°C threshold crossed for all months since 2022. The Lowess 3-year smoothing trend (red line) indicates that the 2°C threshold was crossed in 2022 and that 3°C may get crossed in 2028 if this trend continues (dashed extension). The picture could look even worse when a genuinely pre-industrial base was used and a polynomial trend was used and extended.

[ Potential Land-only rise, from earlier post ]

Additionally, the image at the top shows very high temperatures in 2025, despite the fact that the year 2025 wasn't an El Niño year. In other words, current temperatures are suppressed. Moving from the bottom of a La Niña to the peak of a strong El Niño can in itself make a difference of more than 0.5°C. This is illustrated by the image below, from an earlier post, that shows a temperature rise of more than 0.5°C from November 2022 to March 2023, when the last El Niño had not yet even started.

[ Temperature rise due to El Niño from earlier post ]

How deep into La Niña conditions are we at the moment? Sea surface temperatures in the Niño-3.4 region of the equatorial Pacific Ocean (5°N-5°S, 120°W-170°W) are indicative for El Niño/La Niña conditions. The image below shows the location of that region (square on the globe, inset) and graphs with the sea surface temperatures in the Niño-3.4 region for each of the days of the years from 1981 through December 27, 2025.

The image below shows a graph with temperature anomalies in the Niño-3.4 region from 1950 through November 2025, when the anomaly was -0.68°C.

[ click on images to enlarge , from earlier post ]

The image on the right shows a NOAA update of Niño-3.4 region temperature anomalies and forecasts. NOAA considers La Niña conditions to occur when a one-month negative sea surface temperature anomaly of -0.5° C or less is observed in the Niño-3.4 region of the equatorial Pacific Ocean (5°N-5°S, 120°W-170°W) and is forecasted to persist for three consecutive months. Also, an atmospheric response typically associated with La Niña must be observed over the equatorial Pacific Ocean.

[ from an earlier post ]

The image on the right, adapted from NOAA, shows ENSO (El Niño-Southern Oscillation) probabilities, with El Niño (red bar) emerging in the course of 2026.

The graph below, adapted from tropicaltidbits, uses CDAS (Climate Data Assimilation System) data showing an anomaly of -1.272°C on Dec 28, 2025. The graph gives another idea as to how deep we have descended into La Niña conditions.

The CDAS analysis below shows very low sea surface temperature anomalies (in blue) in the Niño3.4 region in the Central Pacific on December 28, 2025.

The image below, adapted from ECMWF, shows the ENSO anomalies and forecasts for developments through November 2026 in Niño3.4 (left panel) and in Niño1+2 (right panel), indicating that the next El Niño will emerge and strengthen in the course of 2026.

[ from earlier post ]

How large could the temperatures rise be?

Moving from the depth of a La Niña to the peak of a strong El Niño in itself could make a difference in the global temperature of more than 0.5°C, as said. This could trigger a huge temperature rise, since the rise is already accelerating, due to feedbacks such as albedo loss and increased water vapor in the atmosphere.

Albedo loss could be caused by loss of Antarctic sea ice, resulting in elevated global temperatures that could persist through September 2026, when Arctic sea ice typically reaches its minimum extent. Rising temperatures come with further feedbacks, such as loss of lower clouds. The image below shows a forecast for September 2026 of very high temperature anomalies around Antarctica and over the Arctic Ocean.

[ from earlier post ]

There is a huge danger that seafloor methane and methane from thawing terrestrial permafrost will add strongly and abruptly to the temperature rise, as discussed in many earlier posts such as this one and as illustrated by the screenshot below.

[ screenshot from earlier post ]

The methane danger is further illustrated by the image below that shows hourly average in situ methane measurements well above 2400 ppb (parts per billion). The image is adapted from an image issued by NOAA December 29, 2025. The image shows methane recorded over the past few years at the Barrow Atmospheric Baseline Observatory (BRW), a NOAA facility located near Utqiaġvik (formerly Barrow), Alaska, at 71.32 degrees North latitude.

Climate Emergency Declaration

UN secretary-general António Guterres recently spoke about the need for “a credible global response plan to get us on track” regarding the international goal of limiting the global temperature rise. “The science demands action, the law commands it,” Guterres said, in reference to a recent international court of justice ruling. “The economics compel it and people are calling for it.”

What could be added is that 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 this 2022 post and this one and as discussed in the Climate Plan group.