The daily average CO₂ at Mauna Loa, Hawaii, was 428.60 parts per million (ppm) on February 6, 2025, the highest daily average on record. The previous record high was 428.59 ppm on April 26, 2024. To find higher levels, one needs to go back millions of years (see inset).
Carbon dioxide typically reaches its annual maximum in May, so even higher levels can be expected over the next few months.
The image below was part of an analysis of NOAA data for an August 2024 post and has a trend added based on August 2009 through July 2024 data. The trend points at 430 ppm CO₂ getting crossed in February 2025, which would constitute a jump of 10 ppm in two years time (from 420 ppm in February 2023 to 430 ppm in February 2025).
The mean annual carbon dioxide was 424.61 ppm in 2024, an increase of 3.53 ppm compared to 2023 and the highest annual growth on record, as illustrated by the image below. This record high growth rate indicates that emissions of carbon dioxide are increasing while carbon sinks are weakening at the same time.
The above image and the image below are both from an earlier post. The image below shows a trend, based on 2015-2024 annual data, pointing at 1200 ppm CO₂ getting crossed in the year 2032.
The above trend illustrates that the clouds tipping point could get crossed in early 2032 due to rising CO₂ alone, which on its own could push temperatures up by an additional 8°C. The clouds tipping point is actually at 1200 ppm CO₂e, so when growth of other greenhouse gases and further mechanisms are taken into account, the tipping point could be crossed much earlier than in 2032, possibly as early as in 2026, as discussed in an earlier post.
Climate Emergency Declaration
The situation is dire and the precautionary principle calls for rapid, comprehensive and effective climate 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.
Global sea ice area was 13.03 million km² on February 6, 2025, the lowest area on record, as illustrated by the image below, adapted from seaice.visuals.earth.
What is the difference between sea ice area and extent? Extent is the total region with at least 15% sea ice cover. Extent can include holes or cracks in the sea ice and melt ponds on top of the ice, all having a darker color than ice. Sea ice area is the total region covered by ice alone.
Therefore, sea ice area is a critical measure in regard to albedo. Loss of sea ice area is a self-reinforcing feedback that causes the temperature to rise, resulting in further melting of sea ice, thus accelerating the temperature rise.
A Blue Ocean Event is often defined as crossing a tipping point that is crossed when sea ice falls below 1 million km² in extent. Doesn't it make more sense to look at sea ice area, rather than at sea ice extent?
Loss of albedo as a result of loss in sea ice is only one out of many feedbacks that come with rising temperatures, as described at the Threat.
Antarctic sea ice
There are many mechanisms that are driving up, if not accelerating the temperature rise and loss of sea ice.
As illustrated by the above image, Antarctic sea ice area was 1.05 million km² on Feb 22, 2023, and was 1.50 million km² on Feb 6, 2025. Will there be a Double Blue Ocean Event 2025?
Sea ice thickness is another important measure. The image below shows Antarctic sea ice thickness on four different dates, including February 4, 2025, from the University of Bremen.
For a comparison of Antarctic sea ice thickness at earlier dates, also have a look at this earlier post.
Arctic sea ice
As illustrated by the image below, there are at least seven mechanisms that can accelerate the rise in surface temperatures, and thus in turn accelerating sea ice decline and further accelerating the temperature rise.
Warmer water flowing into the Arctic Ocean causes Arctic sea ice to lose thickness and thus volume, diminishing its capacity to act as a buffer that consumes ocean heat entering the Arctic Ocean from the North Atlantic.
This means that - as sea ice thickness decreases - a lot of incoming ocean heat can no longer be consumed by melting the sea ice from below, and the heat will therefore contribute to higher temperatures of the water of the Arctic Ocean.
[ Arctic sea ice volume, click on images to enlarge ]
The image on the right shows Arctic sea ice volume up to February 6, 2025. Arctic sea ice volume in 2024 and 2025 has been much lower than in previous years.
More incoming heat therefore threatens to reach the seafloor of the Arctic Ocean and destabilize methane hydrates contained in sediments at the seafloor, resulting in eruptions of huge amounts of methane, as illustrated by the above image.
The image below shows that the Arctic temperature, i.e. at latitudes higher than 80°N, on February 6, 2025, was much higher than the mean temperature for the period 1959-2002.
As said, rising temperatures come with many feedbacks, and they can contribute strongly to the further acceleration of the temperature rise. Another feedback is more water vapor ending up in the atmosphere, as illustrated by the image below.
The above image shows the average daily precipitable water anomaly on February 2, 2025. More water vapor is another self-reinforcing feedback, since water vapor is a potent greenhouse gas that further accelerates the temperature rise.
The image below shows Arctic sea ice extent up to February 3, 2025. During the first few months of the year, Arctic sea ice is still growing in extent. The red line and red marker shows 2025 sea ice. Dots mark Arctic sea ice extent on February 3 for the respective year and Arctic sea ice extent was at a record low for the time of year on February 3, 2025, despite La Niña conditions.
A new El Niño may emerge in the course of 2025, while Arctic sea ice extent, area and volume are all at record low, while numerous self-reinforcing feedbacks are kicking in with accelerating ferocity and while temperatures are driven up by further mechanisms, e.g. high sunspots. Such a combination of mechanisms could result in a huge temperature rise and in a Blue Ocean Event in 2025, threatening huge amounts of methane to erupt from the seafloor.
[ Arctic sea ice extent, click on images to enlarge ]
Ominously, very high temperature anomalies are forecast over the Arctic Ocean for November 2025.
[ Very high temperature anomalies forecast over Arctic Ocean, click 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.
[ high temperatures over the North Pole, click on images to enlarge ]
The above image shows high temperatures over the North Pole on February 2, 2025 18z. The green color indicates temperatures above freezing point. The image below shows the temperature anomaly compared to 1979-2000, with the white area within the light pink color over the Arctic indicating a 34°C anomaly.
[ high anomalies over the North Pole ]
A heat flux entered the Arctic early February 2025 causing the temperature at the North Pole to rise to above freezing point, up to 34°C above 1979-2000, as illustrated by the above images by Climate Reanalyzer.
The image on the right shows a North Pole view, with the white area within the light pink color over the Arctic indicating an anomaly of 34°C.
The mechanisms leading to this situation have been described in earlier posts, most recently in this post, which adds that as temperatures rise, a huge amount of heat is accumulating in the North Atlantic and at its surface, and much of this heat can move toward the Arctic due to a sudden acceleration of prevailing wind and ocean currents, an acceleration that is due to deformation of the Jet Stream.
Rising temperatures come with several feedbacks, one of which is deformation of the Jet Stream.
As a result, the movement of heat toward the Arctic can at times be accelerated abruptly by strong longitudinal wind, accompanied by sudden acceleration of the Gulf Stream and its extension northward, as also illustrated by the image on the right showing the situation on February 2, 2025 18Z (wind speed at 250 hPa, Jet Stream).
The image below shows high temperatures hitting the North Pole (green circle) on February 2, 2025 17:00 UTC, i.e. 2.1°C (35.9°F) at 1000 hPa (left panel) and 1.0°C (33.7°F) at surface level (right panel).
The left panel also shows the wind speed at the North Pole (51 km/h), while the right panel also shows the ocean current moving warm water along the coasts of Norway and Svalbard, as an extension of the Gulf Stream.
As warmer water flows into the Arctic Ocean, Arctic sea ice loses volume, which diminishes its capacity to act as a buffer that consumes ocean heat entering the Arctic Ocean from the North Atlantic. This means that less incoming ocean heat can be consumed by melting the sea ice from below, resulting in higher temperatures of the water of the Arctic Ocean.
The image on the right shows Arctic sea ice volume up to January 31, 2025. Arctic sea ice volume in 2024 and 2025 has been much lower than in previous years. More incoming heat therefore threatens to reach the seafloor of the Arctic Ocean and destabilize methane hydrates contained in sediments at the seafloor, resulting in eruptions of huge amounts of methane, as illustrated by the above image.
Rising temperatures come with many feedbacks, and they can contribute strongly to the further acceleration of the temperature rise. One example is more water vapor ending up in the atmosphere, as illustrated by the image below, showing the average precipitable water anomaly on February 2, 2025.
The image below shows Arctic sea ice extent up to January 31, 2025, when it was at a record low for the time of year.
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 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.
A huge temperature rise
Copernicus issued the January 31, 2025 temperature anomaly, as illustrated by the image below.
With all data available for January 2025, the average monthly temperature anomaly can be calculated. For January 2025, the temperature anomaly is 0.79°C above 1991-2020, higher the annual 2023 temperature anomaly of 0.6°C above 1991-2020 and higher also than the annual 2024 temperature anomaly of 0.79°C above 1991-2020.
Warnings about the potential for a huge rise in temperature have been sounded before, e.g. see the extinction page and the image below with daily data and added trends.
[ temperatures keep rising, despite La Niña, click on images to enlarge ]
While La Niña conditions are definitely present in January 2025, the La Niña is expected to be short-lived. Temperatures are typically suppressed during La Niña. Despite temperatures being suppressed, the global surface air temperature reached 13.29°C on January 26, 2025, the highest temperature on record for the time of year, according to ERA5 data. Temperatures keep rising, as indicated by the trends added to the data, despite La Niña. Will a new El Niño emerge in the course of 2025?
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.
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.
“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?
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 and the update of the image below with daily data and added trends.
[ Temperature anomaly with ENSO shading, trends added, click on images to enlarge ]
While La Niña conditions are definitely present in January 2025, the La Niña is expected to be short-lived. Temperatures are typically suppressed during La Niña. Despite temperatures being suppressed, the global surface air temperature reached 13.28°C on January 24, 2025, the highest temperature on record for the time of year, according to ERA5 data. Temperatures keep rising, as indicated by the trends added to the data, despite La Niña. Will a new El Niño emerge in the course of 2025?
Human extinction at 3°C
If the temperature does indeed keep rising rapidly, the anomaly compared to pre-industrial may soon 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 (2019) finds that, due to co-extinction, global biodiversity collapse occurs at around 5°C heating, as discussed in this 2019 post. The post adds 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.
Antarctic sea ice
Antarctic sea ice is losing thickness, as illustrated by the images below, showing thickness from August 27, 2024, to January 21, 2025.
[ click on images to enlarge ]
Measuring polar temperatures
As mentioned above, different ways of measuring polar temperatures can lead to different results. The combination image below illustrates that using a different smoothing radius for Arctic measurements can result in different anomalies. Gray areas signify missing data. Ocean data are not used over land nor within 100 km of a reporting land station.
The image below shows December 2024 Arctic temperature anomalies compared to 1951-1980 using ERA5 data.
The above image raises the question as to what caused the low anomalies over Greenland and Baffin Bay, compared to the rest of the Arctic. This could be caused by changes to wind and ocean currents.
Changes to wind and ocean currents
The increase in the Earth's energy imbalance results in an increase in kinetic energy in the atmosphere and oceans, i.e. stronger wind and stronger ocean currents, both in longitudinal and latitudinal directions. An earlier post points at a study that found increased kinetic energy in about 76% of the upper 2,000 meters of global oceans, as a result of intensification of surface winds since the 1990s.
While the wind overall is strengthening, the wind mainly appears to be strengthening in latitudinal directions. The Coriolis Effect contributes to that, but strengthening of latitudinal winds appears to be getting stronger over the years. Loss of sea ice at the poles comes with loss of albedo, a self-reinforcing feedback that contributes to polar amplification of the temperature rise, which contributes to the reasons why longitudinal wind is not strengthening as much as latitudinal wind.
Polar amplification narrows the difference in temperature between the Equator and the Poles, which results in a relative slowing down of the speed at which heat flows from the Equator to the poles (longitudinal wind). This causes changes in both wind patterns and ocean currents, such as deformation of the Jet Stream, slowing down of the Atlantic meridional overturning circulation (AMOC), and changes in ocean currents around Antarctica that carry heat from the Southern Ocean closer to Antarctica and from there to the deeper ocean.
Deformation of the Jet Stream can cause cold air from the Arctic to descend deep over the continents.
[ temperature of -37°C in Colorado ]
The image on the right shows that a temperature of -37.0°C (or -34.7°F) was recorded in Colorado on January 21, 2025 (07:00 UTC).
Very low North American temperatures occurred, while sea surface temperatures kept increasing. Such conditions can strongly increase the temperature difference between land and sea, especially during the northern summer. This can in turn further strengthen latitudinal wind.
On January 25, 2025 07:00 UTC, wind at 250 hPa (Jet Stream) at the green circle is forecast to reach a speed of 401 km/h and wind power density of 271.3 kW/m².
[ strong wind over the North Atlantic, click on images to enlarge ]
While such conditions vary with the weather, all such mechanisms can contribute to strengthening wind speed, especially in latitudinal directions, as illustrated by the image below.
The above image shows the wind speed anomaly in December 2024 at 250 hPa (Jet Stream). The image below shows how this keeps cold air in December 2024 at 250 hPa over elevated land in the Arctic in place, thus keeping temperatures low over Greenland and Baffin Island.
As temperatures rise, stronger horizontal (latitudinal) wind will result in more heat accumulating in the Atlantic ocean, the Pacific Ocean and the Indian Ocean.
At times, though, wind can abruptly and dramatically strengthen in vertical (longitudinal) direction. This can be facilitated by geological features, e.g. in the North Atlantic, there is an easy pathway northward from the Gulf of Mexico to the Arctic Ocean. At times, the wind and ocean currents along this path can be accelerated by weather conditions such as storms and hurricanes.
As an example, the above image shows a forecast for February 2, 2025 12Z, of strong wind at 250 hPa over the North Atlantic. The image below shows a forecast for February 2, 2025 12Z, of temperature anomalies.
As temperatures rise, a lot of heat is accumulating in the North Atlantic and at its surface. Much of that heat can be pushed abruptly into the Arctic by strong longitudinal wind, accompanied by sudden acceleration of the Gulf Stream and its extension northward. Accordingly, this can cause a huge temperature peak in the Arctic. Similar hazards apply to the water and sea ice around Antarctica.
The impact of extreme weather events can be missed in climate models that average away peaks in temperature and wind strength. However, wind peaks can contribute to massive storm damage, flooding and fire hazards. The joint impact of high temperature peaks and high humidity can cause fatal heat stress. High temperatures and strong wind can also cause a sudden decline of sea ice that can contribute to cause huge amounts of methane to erupt abruptly from the seafloor, in turn contributing strongly to temperature rises that are not foreseen in many climate models.
Arctic sea ice
Meanwhile, ocean heat keeps increasing, resulting in melting of sea ice from below. The image below shows Arctic sea ice extent through January 19, 2025.
[ 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 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.
[ Northern Hemisphere sea surface temperature anomaly, click to enlarge]
[ Arctic sea ice volume, click on images to enlarge]
The above image shows a green circle south of Svalbard with a 5.1°C sea surface temperature on January 18, 2025, 3.4°C higher than 1981-2011.
High ocean temperatures result in low Arctic sea ice volume, as illustrated by the image on the right and as 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.
