ISSN (Print) - 0012-9976 | ISSN (Online) - 2349-8846

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Breaching 400 ppm

A reminder that the world must move towards alternative energy sources.

On 9 May, the Earth Systems Research Laboratory located near the Mauna Loa volcano in Hawaii recorded that the carbon dioxide (CO2) levels in the earth’s atmosphere had reached 400 ppm (parts per million). The last time, scientists tell us, the earth supported so much CO2 was around three million years ago when there was no human life on the planet. In fact, the Hawaii laboratory’s data was not the first to note that CO2 levels had touched this level. Last year, monitoring stations at the South Pole had also measured 400 ppm.

The Hawaii data is significant because it is part of the long-term measurements of CO2 levels started by the scientist Charles David Keeling in 1958. Since then, when the levels noted were 315 ppm, the “Keeling Curve” has recorded the gradual and relentless increase in CO2 levels, thereby confirming the concern of climate scientists that this will eventually result in global warming to a point where changes caused by it are irreversible, and perhaps of a magnitude which will make adaptation a challenge. Yet the 9 May recording caused only a minor ripple. Climate change campaigners took note and urged action; climate sceptics continued to voice their doubts.

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