Tuesday, December 9, 2014

Last Plane out of Lima

Lies lies
I can't believe a word you say
 - The Knickerbockers

How come you say you do
when you don't?
-Carl Perkins

       The Lima talks are grinding  along, without much hope of any movement forward.  see US defends moving backward from Copenhagen pledge.   Perhaps its a good time to look at the realistic best and worst case, without any action.  This requires a close look at the basics, how much fossil fuel will we burn?
        Of all the thousands of papers in the climate change literature, remarkably few deal with the central issue - the amount of carbon we are likely to emit, in light of resource limits - i.e. peak fossil fuels.  
      This is a bit strange, given the key role such fuels play in the modeling.     The IPCC appears to think that that we have an infinite amount of fossil fuels to burn,or at least enough to burn more and more, out past 2100   .   So, naturally CO2  and temperature rise, and  various catastrophes occur. -  cities under water, deserts sprouting up,  and even (potential)  human extinction!
       Meanwhile , geologists seem fairly confident that resource production peaks do occur, and have occurred, and are likely to occur world wide in the not to distant future.   
      Is this a case of GIGO?  (garbage in garbage out).    Or should we ignore the geologists, and assume the worst?  
      I recently came a cross a paper which addresses this issue in some detail.  It's called "Depletion of fossil fuels and anthropogenic climate change—A review". Energy Policy 52, 797–809.  by  Höök, M., & Tang, X., 2013  ( Full paper  here   . http://bit.ly/1s0c7hm   (PDF 22 pages)
        The authors go into some detail about the IPCC,  scenarios and how they are developed.  (Special Report of Emission Scenarios or SRES).  .  Apparently the idea of peak resources was considered and rejected, concluding that   “...the sheer size of the fossil resource base makes fossil sources an energy supply option for many centuries to come.”      As a result  "...energy production from fossil fuels in the SRES outlooks range from a mere 50%, increase from year 2010 in the B1 family to over 400% in the A1 family."
       Needless to say, such assumptions are likely to be pretty far off the mark.  I leave it to the reader to explore,the authors discussion of  the many optimistic ideas which underlie these assumptions. They include, optimistic assumptions about the size of  resources themselves, ,  as well as assumptions about:  the ease of turning these stocks into flows,  the idea that these fuels are substitutes for each other,  the economic consequences of peak oil, and the decline in EROI of resources.
         However, recognizing that we may not "burn ourselves off the planet", doesn't mean that we can't do ourselves harm by burning what is left.  The authors review a number of papers which use more  "realistic" assumptions about resources, and they generally show a concentration peaking at between 400-500 ppm.  Depending on your assumptions about "climate sensitivity"  this could result in temperature increase of .9 to 2.0 , relative to year 2000.
              Typical of these studies was that of Hanson (2008)
"Kharecha and Hansen (2008) used a Bern carbon cycle model and a set of peak oil and gascompatible emission scenarios to explore the implications of peak oil for climate change. It should be noted that they considered coal to be abundant and capable of increasing production up to 2100 in a business-as-usual outlook, resulting in 550 ppm CO2 in the atmosphere. Four other scenarios had more constrained coal production profiles, somewhat more compatible with published peak coal projections (Mohr and Evans, 2009; Höök et al., 2010b; Patzek and Croft, 2010: Rutledge, 2011). The CO2 concentration ended up around 450 ppm for these scenarios and they were found to be largely consistent with current assessments of the cumulative 21st century emissions needed to stabilize atmospheric CO2 at 450 ppm even after factoring in carbon cycle feedbacks".
           There is one aspect that gives me pause about these studies -  they assume that economic growth will continue after  "peak cheap oil".  However, this view is not universal see Energy return on Investment, Peak Oil, and the end of economic growth  (2011)  Murphy and Hall .  They argue that economic growth requires low oil prices, and an increasing oil supply.  These conditions are unlikely to occur.   A lack of economic growth, could make it uneconomical to remove and burn some of the remaining expensive fossil fuels.  While this is no cure for human caused climate change, it could at least make it less disastrous.
       So the bottom line is - if you accept that fossil fuels will peak - the worst case is probably around 450, which may be 2 degrees.  However, assuming peak cheap oil creates a new "Greater Recession", that number could be lower.
      Peak cheap oil could achieve more than Kyoto, Copenhagen or Lima, and could put us on a glide path to "degrowth".  Of course this type of involuntary de-growth, or Greater Recession", creates its own problems !!
        I recently heard a talk by Nate Hagens at a degrowth conference held in Vancouver. see here.    Towards the end he said something like "Most of the presenters at this conference are recommending degrowth as a good policy option.  I am saying something different.  De growth is not optional. It is inevitable, And it will start soon."
        Along the same lines, here is an except from an interview with Tom Murphy , UC physics professor, and blogger at Do The Math                    
      " What are your views on climate change?
TM: I see climate change as a serious threat to natural services and species survival, perhaps ultimately having a very negative impact on humanity. But resource depletion trumps climate change for me, because I think this has the potential to effect far more people on a far shorter timescale with far greater certainty. Our economic model is based on growth, setting us on a collision course with nature. When it becomes clear that growth cannot continue, the ramifications can be sudden and severe. So my focus is more on averting the chaos of economic/resource/agriculture/distribution collapse, which stands to wipe out much of what we have accomplished in the fossil fuel age. To the extent that climate change and resource limits are both served by a deliberate and aggressive transition away from fossil fuels, I see a natural alliance. Will it be enough to avert disaster (in climate or human welfare)? Who can know -- but I vote that we try real hard.


see also Ugo Bardi's piece on the oildrum (2009)
At this point, there is no consensus among the authors in terms of policy recommendations relating to these results. Some of the authors cited here conclude that peaking of fossil fuel production will be sufficient to maintain CO2 at a level below that considered dangerous by many climate experts. But this conclusion is not shared by other authors who maintain, instead, that even if we could be sure that CO2 concentrations would remain in the 450-550 ppm range, we would still face dangerous levels of global warming. Clearly, this is a difficult issue to solve, given the uncertainty in the scenarios and in the calculations of CO2 concentration in the atmosphere and the temperature effects. Furthermore, there are several phenomena that the climate models don't consider and that could make warming much more serious than currently believed. Among these, the saturation of the CO2 sinks, the positive feedback of the methane hydrates and those of the ice/albedo system. We just don't know enough to be able to say whether depletion is enough to "save" us from global warming.
However, it may not matter which threat one considers the most immediate: there exist measures that will mitigate both global warming and depletion. These are energy efficiency and replacing fossil fuels with nuclear energy or renewables. There is only one mitigation measure that doesn't cut both ways: CO2 geological sequestration. If depletion is a more immediate problem than global warming, clearly it would make no sense to waste precious resources in removing CO2 from the atmosphere. On the other hand, if oil and gas depletion leads us to rely more on coal, then sequestration might be necessary.
In my opinion, the studies I have discussed show that there are serious threats looming ahead. I believe that whether the threat be depletion or warming, we should move away from fossil fuels as fast as possible. Still, it is not at all certain that what we can do will be enough and we might well suffer for both effects: lack of fuels and global warming. It wouldn't be "fire or ice", but fire and ice.

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