The Other Sad Task of Combating Climate Change

Writing this kind of blog post tends to freeze my brain.  I find it astounding sometimes to be trying to present in a logical and calm fashion a description of horrors.  But there it is.

I noticed in perusing comments in various climate-change-related web sites that even among fairly well-informed folks there seems to be a misperception, which runs something like this:  The job of combating climate change is about slowing carbon emissions, preferably as quickly as possible.  As I understand it, that is half right.  There is another distinct task:  leaving at least a significant amount of carbon-emitting “fossil fuels” in the ground – forever, or at least for the next 100-1000 years.  Moreover, that task assumes that we do not discover major new sources of oil, natural gas, and coal.  If we do, then we need to leave the equivalent of a significant amount of present “reserves” plus all reserves discovered in the future in the ground.

One implication of this:  we need to understand that there is a Hard Stop somewhere in the future, a point beyond which we dare not use even one milligram more of fossil fuels.  If we cut carbon emissions drastically in the near future, and keep them cut, that Hard Stop almost certainly will never arrive – instead, we will suffer various degrees of what Joe Romm calls “Hell and High Water”, involving at worst the decimation (not in the Roman sense – in the sense that 9/10ths of humanity will die, mostly of starvation, disease, and poisoned air) of humankind.  If we continue on the present path of fossil-fuel use increases and minor moves towards “sustainability”, the so-called “business as usual”, that Hard Stop may even arrive by the end of this century.  That Hard Stop represents absolutely no further use of fossil fuels because the alternative might be the end of all life on earth, forever.

How can I say this?  How can I not be wildly exaggerating, in Mark Twain’s sense (“the reports of my death are wildly exaggerated”)?

Keystone and Game Over

It may strike people as odd that there is such an environmental furor over one oil pipeline project in the US (the Keystone XL proposal).  Here’s a frequently cited quote (paraphrased) by Dr. James Hansen on the subject:  “If Keystone XL goes forward, then it’s game over for the climate.”  Most people, my sense is, read that as meaning that some form of “Hell and High Water” becomes inevitable.  I believe that instead, he is also referring to a previous quote (in, I believe, his book Storms of My Grandchildren, and also paraphrased):  “If we use all our present reserves of coal and oil, there is a significant chance of a runaway greenhouse effect.  If we also use all our tar sands and oil shale, I view the runaway greenhouse effect as likely.” Before I explain my understanding of this, let’s note that Keystone XL transports oil derived from Canadian tar sands to US ports for export abroad.

What’s a runaway greenhouse effect?  If we look at Venus, we see a planet with extreme heat and with acid rain that dissolves any life forms that might exist in the air, and then evaporates before it reaches the surface.  However, if Venus had no atmosphere, there would be no extreme heat and no acid rain.  Instead the temperature would be a significant distance below the “runaway point” (estimated by Dr. Hansen at somewhere around 62 degrees Fahrenheit, iirc). Carbon or other substances in the atmosphere reflect light-generated heat bounced from the surface back to the surface again, trapping it – and also increasing the acidity of water (again, as I understand it).  If Earth passes that “runaway point”, then we will become like Venus.

Now, Earth without an atmosphere would be far below the temperature of Venus – below freezing, actually.  The atmosphere adds one layer of carbon-based reflection or “trapping” of heat (yes, I realize I’m simplifying drastically).  Life itself – all life, especially vegetable – adds another.  Life is carbon-based, and it creates a carbon cycle that emits carbon to the atmosphere, and then absorbs it in non-organic matter when it returns, via a process called “weathering” that deposits much of the carbon returned into the oceans. In ordinary times, this creates a way of handling perturbations in carbon emissions so that one returns eventually to somewhat of a “steady state”. And that “steady state” is still clearly under the “runaway point.”

Now here is where we get to the importance of leaving some fossil fuels in the ground.  Because we have seen “Hell and High Water” in the past, and life has been decimated but survived.  But what are fossil fuels, really?  Primarily the carbon deposited in the ground by life – especially vegetable life – over the last up to a billion years or so.  Now compare this episode of carbon emissions to all past episodes.  We have seen surges in carbon emissions from the Milankovitch cycle before, and from long-term underwater eruptions that bring new carbon up from the Earth’s core to the air.  We have seen methane spurts due to accompanying thawing of places like the Arctic that may have made the temperature rises and carbon in the atmosphere more extreme.  What we have never seen before is taking all the stored carbon for hundreds of millions of years and injecting it into the atmosphere over what could turn out to be a period of 200 years (and carbon has a half-life of perhaps 100 years in the atmosphere). 

And Hansen’s best estimate is that use of all of that stored carbon over a period even of much longer than 200 years is likely to bring on a runaway greenhouse effect.  This is because the ocean is the primary way of restoring equilibrium to the system, and at some point before we use up all that carbon, if we do it fast enough now, the ocean stops being able to absorb as much carbon (apparently, according to Wikipedia, because of the slowing of the “biological pump”) – and carbon coming down from the atmosphere cycles right back up again.  And so, once that point is reached, carbon doesn’t cycle very much back into the ocean – it goes on accumulating in the atmosphere, for a thousand years or more, until the ocean begins to regain its ability to absorb carbon. Thus, as we get close to the “runaway point”, we can’t just slow carbon emissions down to a point at which as much carbon is returning as is being emitted – the only point at which that is true is near-zero emissions, a Hard Stop.

Now, hopefully, you begin to see why it’s important to leave significant amounts of fossil fuels in the ground for at least 100-1000 years:  it keeps us away from that Hard Stop, and hence that “runaway point.”  It keeps us away from the ultimate horror.

So why is Keystone XL so critical to this?  There is at present no real market for tar sands oil.  There are very high up-front costs, which only the Canadian government has taken on so far – and no one appears likely to, in the immediate future, if the Canadians don’t succeed.  The only realistic way of getting that oil from inland Canada to a decent market, it appears, is to add to existing pipelines and send it to ports in the southern US – all other routes appear to involve too-large costs and times of building new infrastructure – and further carbon emissions from tar sands oil will be minimal. If Keystone XL goes through, it appears likely that a significant portion of the world’s tar sand oil will be emitted over the next 40 years – if not, not.

That’s why Keystone XL matters.  That’s why Hansen has been campaigning for several years to stop most worldwide production of coal, as the least painful way of avoiding the “significant chance” of a runaway greenhouse effect. That’s why people need to think about handling climate change today as not simply a matter of adaptation to “Hell and High Water” or slowing down carbon emissions by a couple of percentage points per year right now.  It has now reached the point where we need to face the idea of effectively never using some of those fossil fuels – not just letting the market assume that using it all is OK.

Action Items and Dyslogy

What our sad other task of facing climate change amounts to, therefore, imho, is not only to stop Keystone XL in its tracks.  It amounts to making sure that Keystone and its ilk never happen.  It also amounts to trying to ensure, with each future use of fossil fuels, that a comparable amount of reserves is made unusable, effectively, forever (or until 1000 years from now, whichever comes first).  And it means keeping an eye on new sources of fossil fuels, to limit their use sharply forever.

And if we fail?  I suppose we can write a eulogy for life on Earth.  Except that writing a eulogy for a species that ended life forever seems a bit off, somehow.  The opposite of Utopia is dystopia; I guess we should write a dyslogy.  Someone recently passed me the end of a Swinburne poem that seems to fit – it even includes the sea rise that’s an initial stage.  I have changed one word.

Here death may deal not again for ever;

       Here change may come not till all change end.

From the graves they have made they shall rise up never,

       Who have left nought living to ravage and rend.

Earth, stones, and thorns of the wild ground growing,

       While the sun and the rain live, these shall be;

Till a last wind's breath upon all these blowing

               Roll the sea.

Till the slow sea rise and the sheer cliff crumble,

       Till terrace and meadow the deep gulfs drink,

Till the strength of the waves of the high tides humble

       The fields that lessen, the rocks that shrink,

Here now in his triumph where all things falter,

       Stretched out on the spoils that his own hand spread,

As a god self-slain on his own strange altar,

               Man [Swinburne – Death] lies dead.