While Britain celebrates (Monarchists should not click on that link, be warned) its Queen’s Diamond Jubilee, and New Zealand hibernates on her birthday (which, of course, it isn’t), the planet has hit a notable milestone on its rapid transition to a new climate state. From way up in the Arctic, where the early summer melt is in full swing (click on the thumbnail to see more), NOAA reports that:
The concentration of carbon dioxide in the atmosphere of Barrow, Alaska, reached 400 parts per million (ppm) this spring, according to NOAA measurements, the first time a monthly average measurement for the greenhouse gas attained the 400 ppm mark in a remote location.
And it won’t be long before the rest of us get there:
“The northern sites in our monitoring network tell us what is coming soon to the globe as a whole,” said Pieter Tans, an atmospheric scientist with NOAA’s Earth System Research Laboratory (ESRL) in Boulder, Colo. “We will likely see global average CO2 concentrations reach 400 ppm about 2016.”
Which gives me an excellent excuse to post two graphics, the first from NOAA’s CarbonTracker:
The recent 400ppm at Barrow represents the latest dot on the extreme right of the graph. The South Pole will catch up in a year or two…
Also from NOAA’s Earth System Research Lab in Boulder, Colorado, is a superb visualisation of atmospheric CO2 levels over the last 800,000 years, which rather dramatically demonstrates just how unusual the current situation is:
We’re sitting on the top of that spike, desperately burning fossil fuels to make it go higher. One day before too long the planet will catch up and there will be, quite literally, hell to pay.