08 Sept. 2007
SETI League
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Fun With Mirrors, Part 3

In the last two lengthy and rather complicated blogitems, I did some <gasp>research</gasp>, made some calculations, and reached what I consider to be three somewhat surprising conclusions.

  • In Part 1 I calculated that you could "remediate" the energy consumption of your car simply by painting part of your driveway white.

  • In Part 2, I calculated that you could "remediate" the carbon dioxide emission of your car simply by painting a smaller additional portion of your driveway white.  Because CO2 is cumulative, you would have to paint a bit more every year.

  • Implicit in the Part 2 calculation, and surprisingly so, the annual contribution of CO2 warming was much less than the almost universally ignored effect of using energy in the first place.  This is not, however, totally unjustifiable since the CO2 accumulation overwhelms the annual contribution.

If you think about these conclusions for a while, you'll come to some yourself.  If you're a serious environmentalist, you may well consider painting your own driveway white.  If you're the opposite, you may conclude that the whole CO2 business is a crock if it requires so little to eliminate it.  If you're properly skeptical, however, the first thing you'll do is try to decide whether my conclusions make any scientific sense at all.


Real science of the non-blogitem variety is conducted in a somewhat formalized way.  Usually a knowledgeable, qualified specialist will come up with a hypothesis and try to prove or disprove it with some combination of research and experiment.  Next, he will write up the results in a carefully considered "paper," submit it to his colleagues for comments, submit it to a journal for "peer review" and, assuming it's still considered worthy, it will be edited within an inch of its life for grammar, style, and scientific lucidity (and lay impenetrability).

Richard's blogitem science is somewhat less formal.  I resemble a "knowledgeable, qualified specialist" much as a "democratic people's republic" resembles a democracy.  My two "papers" were carefully considered while I was driving and swimming, activities that don't otherwise absorb my entire alleged intellect.  My colleagues, who don't have the time or interest to read these musings, did exactly thatnot read themand they are no more qualified than I in any event.  As far as "peer review" is concerned, that's up to my thousands of millireaders.  Thus far I have heard from none as to the merits of the conclusions, although two gentlemen among them did point out a careless mistake in conversion, an arithmetic typo, and an instance of apostrophic excess.  All these have been silently remedied.  As for grammar, style, and/or lucidity (of either persuasion), I make no claims at all.

Which is NOT to Imply that I'm Wrong

Because I am without the accoutrements of true science people, I at least make an attempt at validation-by-introspection.  Just as I carefully considered the startling conclusion in my three-part series on "Traffic Analysis," so did I at least think about what I said here to see if it makes intuitive sense or is totally irrational.

Is it possible to "remediate" extra heat created by CO2 absorption, the burning of fossil fuels or generated in other ways, such as with nuclear power?  Absolutely and obviously.  Look at any picture of earth taken from space.  You see clouds, water, and land.  It's intuitively obvious that if there were more clouds, for example, the albedo (reflectance) would be higher and the earth would absorb less solar energy.  Conceptually, therefore, my scheme makes sense.  Remaining to be validated are the "numbers."  Have I made an enormous error?  Almost certainly not in the sense of requiring too much painting.  If you could solve the problem by putting out the occasional ceiling tile, it wouldn't be a problem to begin with.  How about in the other direction?  Am I drastically underestimating the amount of "remediation" required?  I don't think so, but perhaps I'm wrong.  In fact, I have found a mistake in my original assumptions, but a relatively small one.  See if you can spot it before looking at the answer below.

Although I Was Wrong Earlier

In fact, when I originally wrote Part 2, the combination of a mistaken assumption (that I should consider only fossil fuel burned in vehicles instead of all fossil fuel) combined with a misplaced decimal point led me to the opposite conclusion of the one now in the blogitem.  In that version, I said that my annual CO2 warming contribution was greater than that of my fuel energy warming.  I had to re-write my conclusion when I corrected my calculations.  Wouldn't it be nice if everyone altered their conclusions when the facts were shown to be different?  OK, I'm getting political; I'll shut up now.

Summary but no Mirrors (Yet)

What I seem to have said in this three-part series is that there are innovative ways we as individuals can help deal with the climate change problem, if problem it be.  This may turn out to be worth knowing.

Fun with Mirrors tomorrow.

Your Corrections In This Space

This space is reserved for errors that you, my thousands of millireaders that I have drafted into the Peer Review Corps, may discover. 

My Corrections In This Space

In Part 1, where I was calculating the "efficiency multipliers" of the mirror, I neglected to explicitly account for the following:  Although much of the sun's energy is radiated in the visible wavelengths, some is radiated in the infrared.  And, although much of this infrared is absorbed on the way down, which factor is accounted for in the surface radiant flux figure, at least some makes it to the ground.  I tacitly calculated the reflectance change assuming re-radiation of all energy, not just the visible.  To the extent that the mirror or white paint re-radiates the near infrared, no change is needed.  But if it doesn't (on which I have no information) and if, as seems likely, it isn't effective in reradiating any far infrared energy, an additional efficiency correction is needed.  I'm guessing it would be a small one, perhaps .9 or so.  But:  I'm guessing.  This correction would increase the white area needed by 10%, hardly significant given the imprecision of the rest of the information, but humbling in that I didn't think of it at first.

Follow-Up 09 May 2009

See the bottom of this blogitem for a reference to some Real Science (by Real Scientists) on this subject.

NP:  "Close" - The Call

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