Brought to you by Peet's House Blend....
Did you hear? The world has achieved another milestone: 400 parts per million. The monitoring station up on top of Mauna Loa recorded a full day's CO2 measurements where the average came in at 400 ppm. We did it! (Or, more appropriately: Good Lord, man, what have we done?) Don't worry. That number will drop somewhat over the summer as the world's forests and other greenery snarf up a few million tons of that CO2 and photosynthesize it.
Then it will be back, higher than ever. Higher than it's been in three million years, which, if you're playing along at home, you know is longer than human beings have been around. For right now, however, it's kind of cool that the CO2 component of room air, .04%, matches up so perfectly with the Keeling measurements high up in the Hawaiian tradewinds.
Currently, the anthropogenic contribution to CO2 levels is doubling about every 30 years or so, which allows some easy math. The "heritage" level of CO2 (around 1750, at the dawn of the Industrial Age) was about 280 ppm. So, we've pumped another 120 ppm into the atmosphere during these first 260 years or so, but obviously we were just getting started. 280 + (120 x 2) = 520 ppm in 2043.
James Hansen & Co. have modeled some possible outcomes based on these increases in terms of "sensitivity" to CO2 concentrations. Basically, 3 to 4 degrees C equates to a CO2 concentration of 520. That's not good, not good at all. It would be much better to hold the line where we are, although, of course, we won't.
But we should. For the love of God, man, we should. We may get a little more cooperation from....well, from ourselves when the deep ocean heating that has been going on over the last decade begins bubbling up to the atmosphere again. That's where Earth has been parking the additional heat, but it's been masked by a persistent La Niña in the Pacific Oscillation. I've noticed that myself over the last five years or so, out here next to the rim of the Eastern Pacific. I suppose that buffer will dissipate (sort of built into the word "oscillation"), but I hope Earth takes her own sweet time.
It's Mother's Day tomorrow. Don't forget Mother Earth in your remembrances.