CO2 rise is accelerating

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On March 15, 2024, the daily average carbon dioxide (CO₂) at Mauna Loa, Hawaii, was 427.93 parts per million (ppm), as illustrated by the image below, adapted from NOAA. 

This is the highest daily in situ average in the NOAA record at Mauna Loa, which is the more remarkable since the annual CO₂ maximum is typically reached in May, so even higher values are likely to be reached over the next few months. 

The image below, adapted from NOAA, shows 31 days of CO₂ at Mauna Loa, Hawaii. The image shows that a daily mean CO₂ of 427.93 ppm was recorded on March 15, 2024, and that many of the hourly averages that were recorded in April 2024 were higher than 430 ppm.

The image below, adapted from the Scripps Institution of Oceanography, shows that CO₂ at Mauna Loa was 427.80 ppm on March 14, 2024. The background shows six months of CO₂ ending March 15, 2024. 

The image below, adapted from NOAA, shows that the monthly mean CO₂ at Mauna Loa in March 2024 was 425.38 ppm, a growth of 4.39 ppm compared to March 2023. 

The image below, adapted from NOAA, shows that the annual CO₂ growth at Mauna Loa in 2023 was 3.36 ppm, the highest annual growth on record.

Temperature rise

The February 2024 global surface temperature is 1.75°C or 3.15°F when compared to a base of 1886-1915, i.e. a 30-year period centered around the year 1900, as illustrated by the image below. The image shows part (from 1980) of a graph based on NASA Land+Ocean data from January 1880 through February 2024, with the black squares showing the raw monthly data. 

The rise is as large as 2.74°C or 3.132°F when compared to a pre-industrial base and when also taking into account ocean air temperatures and higher polar anomalies, as indicated in the bright yellow inset on the image below. 

Lowess smoothing (red line, 1 year window) highlights variability between years and the huge rise that has occurred recently, which is partly caused by variability such as associated with El Niño. 

The red line also highlights the potential for an even larger rise to come soon, as feedbacks and further developments start to kick in with greater ferocity, contributing to non-linear and abrupt temperature rise, as discussed in earlier posts such as this one and this one

The use of an early date for a pre-industrial base is discussed at the pre-industrial page and is supported by recent analysis of sponges collected in the Caribbean, illustrated by the image below.

[ from earlier post ]

Other recent research debunks the idea that Earth’s surface (across land and sea) has experienced really hot temperatures over the last two billion years. Instead, it shows that Earth has had a relatively stable and mild climate. This makes the threat of a huge temperature rise over the next few years even more menacing. 

The temperature is rising most rapidly in the Arctic. Loss of sea ice threatens to accelerate the temperature rise in the Arctic even more, and cause destabilization of methane hydrates at the bottom of the Arctic Ocean and thawing of permafrost on land, resulting in massive releases of greenhouse gases, further acceleration of the temperature rise and widespread extinction of species (including humans) as early as in the year 2026.

Clouds Tipping Point

The image below illustrates that a polynomial trend (red) can better capture the acceleration in the rise in CO₂ concentration in the atmosphere than a linear trend (blue). 

The red polynomial trend also illustrates how rising CO₂ can cause the clouds tipping point at 1200 ppm to be crossed before 2100, i.e. earlier than anticipated in IPCC models (inset).

Moreover, the clouds tipping point could be crossed much earlier when also taking into account methane. Monthly methane was about 1960 parts per billion (ppb) recently at Mauna Loa, Hawaii, as illustrated by the image below.

A methane concentration of 1960 ppb corresponds, at a Global Warming Potential (GWP) of 200, with a carbon dioxide equivalent (CO₂e) of 392 ppm. Together with the above daily average CO₂ concentration of 427.93 ppm this adds up to a joint CO₂e of 819.93 ppm, i.e. only 380.07 ppm away from the clouds tipping point (at 1200 ppm CO₂e) that on its own could raise the global temperature by 8°C.
This 380.07 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.

Furthermore, nitrous oxide is also rising and there are additional elements that could further speed up the temperatures rise, as discussed at the Extinction page, which shows that, altogether, there is the potential for a temperature rise of well over 18°C by 2026.

A 2018 study (by Strona & Bradshaw) indicates that most life on Earth will disappear with a 5°C rise. Humans, who depend for their survival on many other species, will likely go extinct with a 3°C rise, as illustrated by the image below, from an earlier post.

Environmental crimes

The accelerating growth in carbon dioxide indicates that politicians have failed and are failing to take adequate action. 

Current laws punish people for the most trivial things, while leaving the largest crime one can imagine unpunished: planetary omnicide!

[ from earlier post ]

The image below is from the post Planetwide Ecocide – The Crime Against Life on Earth, by Andrew Glikson
If we accept that crimes against humanity include climate crimes, then politicians who inadequately act on the unfolding climate catastrophe are committing crimes against humanity and they should be brought before the International Criminal Court in The Hague, the Netherlands.

[ image from earlier post ]
Meanwhile, Belgium has recognised ecocide as international crime and the EU Parliament has voted to criminalize the most serious cases of ecosystem destruction. 

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.


• NOAA – Carbon Cycle Gases – Mauna Loa, Hawaii, United States

• Scripps Institution of Oceanography

• NOAA – Weekly average CO2 at Mauna Loa

• NOAA – annual mean carbon dioxide growth rates for Mauna Loa

• NOAA – greenhouse gases at Mauna Loa 
• Belgium becomes first in EU to recognise ecocide as international crime

• ‘Revolutionary’: EU Parliament votes to criminalise most serious cases of ecosystem destruction 

• How long do we have?

• Blue Ocean Event 2024?
• Potential temperature trends

• Co-extinctions annihilate planetary life during extreme environmental change, by Giovanni Strona and Corey Bradshaw (2018)

• NASA GISTEMP – Temperature analysis Plots

• Tragedy set to unfold in tropics

• 300 years of sclerosponge thermometry shows global warming has exceeded 1.5 °C – by Malcolm McCulloch et al. (2024)

discussed at facebook at:

• Oxygen isotope ensemble reveals Earth’s seawater, temperature, and carbon cycle history – by Terry Isson et al.