Atmospheric CO2 hits ‘record’ high as monitoring observatory faces funding cuts

Mauna Loa Solar Observatory [ credit: UCAR]

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It’s only a record in recent times. Warming oceans and seas would be expected to lead to higher CO2 levels anyway, regardless of human activities, due to reduced rates of CO2 absorption and/or more outgassing (depending on the seasons, local temperatures etc.). NASA says: ‘As temperatures rise, carbon dioxide leaks out of the ocean like a glass of root beer going flat on a warm day’. All part of nature’s carbon cycle. Historically CO2 is known to have been a lot higher in certain periods, even many times higher. Now the Mauna Loa observatory ‘faces potential closure’. CO2 is only a trace gas in the atmosphere, a few hundred parts per million in this era – just enough to sustain plants and trees, away from the coldest parts of the polar regions.
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Carbon dioxide levels in the atmosphere reached a record high in April, averaging 431 parts per million (ppm), according to data from the US National Oceanic and Atmospheric Administration’s Mauna Loa Observatory in Hawaii.

The observatory has been tracking atmospheric CO2 since 1958, when April levels stood at under 320 ppm, says Energy Live News.

Pre-industrial CO2 levels are estimated to have been at 280 ppm or below, with even warmer interglacial periods historically topping out at around 300 ppm. [Talkshop comment – depends how far back you go.]

The latest reading represents a significant and sustained departure from those baselines.

CO2 levels tend to peak in April each year as decaying plants release greenhouse gases following winter.

Some of that CO2 is reabsorbed by plants as they grow through warmer months. However, NOAA’s long-term data show average monthly CO2 levels rising steadily year on year.
. . .
The record comes as the observatory faces potential closure. A budget proposal for the 2027 fiscal year includes cuts to numerous climate monitoring facilities, including Mauna Loa.

Full article here.
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Image: Mauna Loa Solar Observatory [credit: UCAR]