Climate Letter #995

If you have read yesterday’s letter you can see that I have reason to believe the goals set by the Paris accord are not meaningful, regardless of what remedial action policies are taken.  My conclusion is that we are going to blow through the 2C target probably well within this century, followed by 3C readings not long after.  The reason is actually well-known to many scientists but has not yet been incorporated into IPCC projections nor a good many climate models.  It is all about permafrost melting and the vast amount of CO2 that is yet to be released along with substantial amounts of methane.  That process has just gotten cranked up, spurred on by fast-rising temperatures in just the last decade or two, and there is nothing in sight to stop it from continuing.  Whatever amounts of gas are released, which unfortunately cannot be easily measured, will be added to the Keeling curve and its counterparts.  Over time there is potential for all of the gas that was locked up during the extended period of ice ages to to be released back into the atmosphere, where it was before the ice ages began some six million years ago, when air temperatures were some 3-4C above pre-industrial.  And that does not count in all the gas we have produced while burning fossil fuels, which will still be around and able to add more warmth.

So should we give up on the Paris goals?  Absolutely not.  We just have to keep in mind that a 4C target might still be attainable, leaving something that can be salvaged for the longer term.  Also, we could perhaps still find some new technologies that could ease the pain.  Here the venerable Arctic scientist Peter Wadhams has a few things to say on that subject:

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A good look at the historical CO2 data.  This site has nine different aspects for viewing, three of which will get special attention below:

–The 800,000 year view. This is where we see rock bottom for the entire ice age, which flattened out with a number of separated readings of around 180 ppm.  We also catch a quick glimpse of the recent run up to 410, which also happens to be quite close to best estimates for what readings probably looked like early in the Pliocene, when the age of Northern Hemisphere glaciers with associated permafrost formation was in its very early stages.  Each big swing in the CO2 curve represents a change of 4-5C in average global temperature and roughly 400 feet of sea level change.  One thing to notice is that whenever CO2 dropped the transformation was one that could quickly and completely be reversed, because the gas was never locked up.  I think that will also prove to be the case on a grand scale covering the entire six-million year era of ice and permafrost that is now in process of coming to an end.

–The 10,000 year view.  This is the one that should blow your mind, fully exposing the amazing excesses of the industrial era.  The damage has been done.  It is kind of like going into debt with a huge spending spree, having a great deal of fun, and then finding out too late that the time for payment has arrived.

–The view since 1700.  It’s perfectly clear that the rise became noticeable soon after 1850, then really took off one century later. The curve itself could hardly be any smoother, nor is there any sign of it changing course.

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