Climate Letter #997

A new understanding of climate change.  The conventional understanding of climate change is that we can prevent a “dangerous” level of warming by reducing the quantity of carbon dioxide emissions produced by human activities, all the way down to zero by a date close to 2050.  A consumption budget is then created depending on how much warming we think we can allow without realizing a chosen level of danger, which is usually set at either 1.5C or 2.0C above the average of the late 19th century.  The lower figure is considered by many to be out of reach, but not the higher one if we get remedial action moving quickly enough.

There is a different way of understanding things which I believe is more realistic and which you may never have heard of before, until I introduced it in the last few letters.  Being absolutely unconventional, this idea can only be set forth as a theory, one that will need an utmost clear and careful explanation.  I think that can be accomplished.

The main conclusion of my theory is that even if emissions from human activity are completely shut down today we cannot stop the warming at 2C, we cannot stop at 3C, and will need to struggle mightily to stop at 4C.  That means there is no carbon budget for human activity except for one that is very negative.  It is all because nature has been awakened and is now taking over as a producer of emissions on a scale that has never been properly accounted for.  In short, nature has the means, and is now on course, to manufacture and release carbon dioxide and other greenhouse gases on a scale that before long will consume the entire carbon budget and then keep right on going, far enough to easily support 3C warming and then approach 4C.  Short of some technological miracle there is nothing we can do to stop those emissions, nor can we readily unwind the gases already placed in the atmosphere.

Nature has several different processes in hand that can produce new emissions.  Carbon movements that occur in and out of the oceans get considerable attention and are most likely important but I think they are extremely hard to measure and certainly hard to visualize.  I have chosen to concentrate on processes created by permafrost activity, which are ample in scale and more accessible to understanding.  There is still a ways to go, but scientists have been making considerable progress in developing useful measurements.  Moreover, it is not difficult to track the carbon pathways in from the atmosphere and back out.  The main weakness for an observer lies in the difficulty of actually measuring quantities of release at any one time, making any curve that attempts to quantify future releases essentially speculative.  Still, an effort must be made, because the potential consequences are so significant.  Likewise there is more that needs to be known about what happens to the carbon once it is released, because not all of it is destined to remain in the atmosphere, just as we know to be the case with human emissions.

It so happens that just today I have found several new stories on the web that add considerable support to my theory.  This one, from a writer at Vox, based on a new scientific study, has a surprising amount of useful information: