Tuesday, April 19, 2016

CO2 and Climate Change: Our Partial Data Promises Hope, Our Best Measure Insists Alarm

For the last five years or so, I have been watching the measures of atmospheric carbon as measured at the peak of Mauna Loa in Hawaii (where contaminating influences on measurements are minimal).  I have become accustomed to monthly reports where CO2 has increased a little more than 2 ppm over the same month the previous year.  This year, things have changed drastically.
On Wed. Apr. 13, for example, I found that (a) monthly CO2 last month had increased by 3.6 ppm year to year; (b) the previous three days had been recorded as about 409.4, 409, and 408.5 ppm, of which the first measurement was about 5 ppm above the same day last year and about 10 ppm above the monthly average 1 ½ years ago, and (c) last year’s average increase had been confirmed as 3.05 ppm, breaking the record set in 1998 for greatest CO2 increase (the data from Mauna Loa go back to 1959).
[UPDATE:  3 weeks ago was the first weekly average above 405 ppm.  Last week was the first weekly average above 406 ppm.  This week was the first weekly average above 408 ppm – 4.59 ppm above the same week last year]
Meanwhile, figures gathered by IEA suggest that fossil-fuel carbon emissions essentially were flat over the 2014-15 time period.  Other studies by CarbonTracker suggest that other net sources and sinks of atmospheric carbon (uptake by the land and the oceans taking carbon from the atmosphere, “fire” [e.g., forest fires on land] acting as a source of atmospheric carbon) have been essentially flat for 15 years or more. 
What is going on?  Why the apparent large rise in Mauna Loa CO2 growth rates over 2014-16 and the apparent flat rate of growth in atmospheric carbon in 2014-15 according to IEA’s data supplemented by CarbonTracker?   Far more importantly, why does the first seem to signal an alarming development in global warming, while the second seems to promise that our efforts in sustainability and global compacts to combat global warming are beginning to bear fruit? And finally, which is right?
[Note:  Because of time constraints, I won’t be able to discuss things in depth.  However, I feel it is important that readers understand the general reasons for my conclusions]

Implications of Hope and Alarm

Let’s start with the second question:  Why does the IEA data seem to offer hope of significant progress in combating global warming, while the Mauna Loa CO2 data seems to signal alarm about the progress of global warming?
If the IEA is right, then over the last 2 years we have begun to make significant progress on reducing fossil-fuel pollution – despite a global economy that grew significantly in 2014 and 2015.  The result is that the rate of growth of CO2 has been flat the last two years.  Because of the recent global climate agreements, we can expect future years to slow the rate of growth, and in the not-too-distant future to begin to actually decrease atmospheric CO2.  Optimistically, we can hope to reach atmospheric stasis at 500 ppm, which will not keep global warming below 2 degrees C, according to Hansen and others, but should keep it below 4 degrees C, where the consequences become much worse.
If the ML CO2 data is right, then we are not only making no significant progress in combating global warming, we may very well be at the start of more rapid warming.  For the last 15 years or so, the rate of growth of atmospheric CO2 has been slightly more than 2 ppm (the previous 15 years saw a growth rate slightly more than 1.5 ppm per year).  A bit more than 2 ppm per year for 15 years translates into about 1 degree Fahrenheit of average global warming.  If we now shift to a bit more than 2.5 ppm per year, that should translate into about 1.3 degrees Fahrenheit of warming over the next 15 years.  It will also mean that we “bake in” 2.67 degrees C of warming since 1850, most of it in the last 60 years, and will be well on the way to about 4 degrees C of warming (blowing past 500 ppm easily) by the 2050-2060 time frame, if we continue with present efforts rather than increasing them.

Which Is Right?

Now let’s tackle questions 1 and 3:  what are the characteristics of the IEA and ML data that lead them to apparently different conclusions, and which of the two is more likely to be right?
Start with the IEA data on fossil-fuel emissions per year.  IEA depends primarily on self-reporting by nations of their use of electricity and heating, supplemented by extrapolation based on prior experience of the amount of CO2 released by coal/gas/oil-based heating and electricity generation. 
There are several reasons to view this data as likely to underestimate actual fossil-fuel emissions, and likely to have that underestimate increase over time.  First, the IEA data does not cover emissions during fossil-fuel production and refining.  The upsurge in fracking would show up in the IEA data as a net decrease in pollution (switching from use of oil to natural gas), while independent studies of wellhead-to-shipment emissions suggest that their total use-plus-produce emissions are almost equivalent to that of oil.  Second, there has been an ongoing shift in business’ fossil-fuel use from Europe/the US to developing countries like China and India.  Not only is these countries’ ability to report the full amount of fossil-fuel emissions less, they are probably less efficient in using fossil fuels to heat and generate electricity in comparable facilities – and the IEA appears to apply the same efficiency standards to comparable facilities in both places.
Now let’s turn to the Mauna Loa CO2 data.  Long experience has determined that any additional CO2 detection from nearby sources is transitory and will wash out in the monthly average.  Likewise, on average, Mauna Loa tracks near the center of Northern Hemisphere response to fossil-fuel emissions primary sources, and can be cross-checked against a global CO2 measure which is one month behind in reporting but has been showing a comparable upsurge (3.4 ppm in February). [Note:  The IEA shows 0% increase in fossil-fuel emissions in 2015, while global and Mauna Loa data show a 0.75% increase in total CO2 emissions]
What are possible causes of the discrepancy aside from underestimated emissions data?  There could be increased “oceanic upgassing” as melting of sea ice allows release of carbon from plants in the newly exposed ocean – not likely, as it is an effect not clearly detected before.  There could be decreased “uptake” from the oceans as they reach their capacity to absorb carbon from the air – but such an uptake slowdown should happen more gradually.  And then there is the el Nino effect.
I haven’t found a good explanation yet of just how el Nino affects CO2 positively, much less how it affects CO2 proportionally to the strength of the effect.  However, the largest recorded el Nino up to this time happened in 1998, data indicate that the 2015-16 el Nino is about as strong, and the 1998 el Nino produced approximately the same outsized jump in CO2 relative to the previous year as the 2015-2016 one has, according to the helpful folks at Arctic Sea Ice (neven1.typepad.com).  So Mauna Loa recent data could be explained as (constant underlying CO2 growth rate) plus (2015-2016 el Nino effect). 
However, aside from all the reasons cited above for being mistrustful of the IEA data, there is another reason to feel that fossil-fuel emissions have actually been going up as well: 1996-99 were years of big economic growth almost certainly leading to large increases in fossil-fuel emissions and thus the underlying CO2 growth rate.  In other words, to be truly compatible with 1998, the equation more likely should be (constant underlying CO2 growth rate) plus (significant 2013-16 increase in fossil-fuel emissions and hence CO2 growth rate) plus (2015-16 el Nino effect).
All this reminds me of the scene in Alice Through the Looking-Glass where Alice starts walking towards her destination and finds herself further away than before.  You have to run much faster to stay in the same place, another character tells her, and much faster than that to get anywhere.  I view it as more likely than not that we are continuing to increase our fossil-fuel contribution, and that we will have to run much harder to keep the CO2 growth rate flat, much harder than that to start the growth rate decreasing, and much harder even than that to begin to decrease overall CO2 any time in the near future.

Facts and the Habit of Despair

In one of Stephen Donaldson’s first books, he imagines a world beset by evil whose only hope is a leper from Earth.  In those days, leprosy had no treatment and the only way for lepers to survive was to constantly survey oneself to detect injuries that dead leprous nerves failed to warn oneself of, every waking second of every day – to constantly face one’s facts.  In the new world, he tells the leader of the fight against evil “You’re going to lose! Face facts!” The leader, well aware that only the leper can save his world, says very carefully, “You have a great respect for facts.”  “I hate facts,” is the response.  “They’re all I’ve got.”
I have concluded above that it is more likely than not that fossil-fuel pollution and therefore the underlying CO2 growth rate continues to grow – and that appears to be the fact delivered by the best data we have, the Mauna Loa and global CO2 measurements.  I hate this fact; but it seems to be what we have. 
And yet, Donaldson’s same series delivers an additional message.  At its improbable world-saving end, the leper asks the Deity responsible for his being picked why he was chosen.  Because, says the Deity, as a leper you had learned that it is not despair, but the habit of despair, that damns [a leper or a world].  To put it in global warming terms:  Yes, the facts are not good.  But getting into the habit of giving up and walking away in despair whenever you are hit by these facts is what will truly damn our world.  Because the horrible consequences of today’s facts are only a fraction of the horrible consequences of giving up permanently because of today’s facts.
To misquote Beckett:  I hate these facts.  I can’t go on.
I’ll go on.

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