Arctic News: record high

Showing posts with label record high. Show all posts

Wednesday, April 1, 2026

Carbon dioxide highest in millions of years

Greenhouse gas concentrations

The highest daily average carbon dioxide (CO₂) concentration on record, 432.69 parts per million (ppm), was recorded at Mauna Loa, Hawaii, on April 1, 2026 (yellow circle on the right). The image below shows hourly (red circles) and daily (yellow circles) averaged CO₂ values from Mauna Loa, Hawaii, over 31 days. In bold on the image are recent daily averages.

The image below shows daily (green circles), weekly (red lines) and monthly (blue lines) averages for the last year. The weekly average for the week beginning on March 22, 2026 was 430.93 ppm (red line top right). As said, CO₂ average daily concentrations were at a record high of 432.69 ppm, at Mauna Loa, Hawaii, on April 1, 2026.

Concentrations of carbon dioxide haven't been this high for millions of years, as confirmed by recent analysis led by Sarah Shackleton and Julia Marks-Peterson. Their analysis finds that, while the average temperature of the ocean has decreased by 2 to 2.5°C over the past 3 million years, average atmospheric carbon dioxide levels have likely remained below 300 parts per million over this time. Methane levels have also remained relatively stable. This makes the recent daily concentration of 431.95 ppm at Mauna Loa and the high recent methane levels (see earlier post) even more threatening and it means that, in addition to the key role of heat-trapping greenhouse gases, there were important contributions from other components of the climate system such as Earth’s reflectivity, variations in vegetation and/or ice cover and ocean circulation.

Could the Northern Hemisphere land-only temperature rise exceed 3°C soon?

The upcoming El Niño could trigger a rapid and steep rise in temperature on land in the Northern Hemisphere, as illustrated by the combination image below that uses land-only data in the top panel and Northern Hemisphere data in the bottom panel.

[ image from earlier post ]

Earth energy imbalance

Climate Emergency Declaration

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.