Monday, March 11, 2013

Unhappy Collisions with Scientific Realities...

Sam Harris has an excellent piece about how it feels when a cherished belief collides with reality as understood by science.  In particular he offers this up as a way for non-believers to understand how it feels to a religious person when science contradicts their faith.  Even without that context, I think it's a great example for anyone who doesn't like (or doesn't believe) what science has discovered.  Here's a snippet from his piece:
On a cold night, most people consider a well-tended fire to be one of the more wholesome pleasures that humanity has produced. A fire, burning safely within the confines of a fireplace or a woodstove, is a visible and tangible source of comfort to us. We love everything about it: the warmth, the beauty of its flames, and—unless one is allergic to smoke—the smell that it imparts to the surrounding air.

I am sorry to say that if you feel this way about a wood fire, you are not only wrong but dangerously misguided. I mean to seriously convince you of this—so you can consider it in part a public service announcement—but please keep in mind that I am drawing an analogy. I want you to be sensitive to how you feel, and to notice the resistance you begin to muster as you consider what I have to say.

Because wood is among the most natural substances on earth, and its use as a fuel is universal, most people imagine that burning wood must be a perfectly benign thing to do. Breathing winter air scented by wood smoke seems utterly unlike puffing on a cigarette or inhaling the exhaust from a passing truck. But this is an illusion.

Here is what we know from a scientific point of view: There is no amount of wood smoke that is good to breathe. It is at least as bad for you as cigarette smoke, and probably much worse. (One study found it to be 30 times more potent a carcinogen.) The smoke from an ordinary wood fire contains hundreds of compounds known to be carcinogenic, mutagenic, teratogenic, and irritating to the respiratory system. Most of the particles generated by burning wood are smaller than one micron—a size believed to be most damaging to our lungs. In fact, these particles are so fine that they can evade our mucociliary defenses and travel directly into the bloodstream, posing a risk to the heart. Particles this size also resist gravitational settling, remaining airborne for weeks at a time. 
Mr. Harris leaves unanswered a related question: how does one decide which science is valid, and should guide one's beliefs?  It would be unscientific to accept all published science results on faith :)   The best approach I know is to read and educate oneself about an area of science that is of interest, then make up your own mind based on the evidence you can see and judge.  What most definitely doesn't work is to read the opinions of others and go with the majority...

Green Cars...

Many people are attracted to either all-electric or hybrid cars because they believe they are helping the environment by doing so – they are “green” cars.  There are other reasons as well, but for many buyers of “green” cars, their green-ness is the major factor.

However, when you take into account the additional carbon footprint and other pollutants produced in the manufacture of both hybrid and all-electric cars, and the indirect carbon footprint and pollution increase from all-electric cars (because they're recharged with electricity produced most often in a non-nuclear power plant), then they don't look quite so green.  Over the average lifetime of a green car, both the carbon footprint and the pollution are worse than the average gasoline-powered car – and there's nothing on the horizon that would change that.  Massive conversion of power plants to nuclear or fusion power would help a lot, but that's not very likely.  Massive conversion to wind or solar doesn't work because there is no known way to store power produced during the daytime for use at night.  Lithium mining is notoriously polluting and energy intensive, but no replacement technology for lithium-ion batteries is even in the laboratory, much less in production.

None of this information is a secret, nor is it hidden or hard to access.  Do a little googling and you can find all you want.  Green cars are a myth (albeit a popular myth!).  They really should be called brown cars.

Bjorn Lomberg (of The Skeptical Environmentalist fame) has a nice summary of this in today's Wall Street Journal)...