I mentioned this last week and its approach (via National Geographic):

An instrument near the summit of Mauna Loa in Hawaii has recorded a long-awaited climate milestone: the amount of carbon dioxide in the atmosphere there has exceeded 400 parts per million (ppm) for the first time in 55 years of measurement — and probably more than 3 million years of Earth history.

(Illustration found here).

And this is just the beginning, folks (Grist): “If you start turning the Titanic long before you hit the iceberg, you can go clear without even spilling a drink of a passenger on deck,” said Richard B. Alley, a climate scientist at the Pennsylvania State University. “If you wait until you’re really close, spilling a lot of drinks is the best you can hope for.”

Of all the breaking news stories, this one is really not braking.