Global concentrations of the greenhouse gas carbon dioxide are measured at Hawaii’s Mauna Loa Observatory as part of the famous “Keeling Curve” record. Readings could hit the symbolic milestone of 400 parts per million of CO2 in air this month. Scripps Oceanography created a website, keelingcurve.ucsd.edu and a Twitter feed @keeling_curve to update daily readings.
Several news organizations have reported on the impending milestone:
Greenhouse Effect: Carbon Concentrations Set to Pass Record High of 400 PPM – Time
Carbon-dioxide levels are at their highest point in at least 800,000 years – Washington Post
Le taux de CO2 dans l’air au plus haut depuis plus de 2,5 millions d’années – Le Monde
As CO2 Concentrations Near Ominous Benchmark, Daily Updates Begin – Scientific American
Up, Up and Away! Scientists Anxious as CO2 Levels to Cross 400 PPM – Bloomberg
Global carbon dioxide levels near worrisome milestone – Nature
Global carbon dioxide levels set to pass 400ppm milestone – The Guardian
Greenhouse-gas levels near milestone: Highest in millions of years – NBC News
CO2-Allzeithoch, Sauerfisch, Religionskrieg – Frankfurter Allgemeine Zeitung