Wednesday, October 30, 2013

Global Warming: Start With The Basics, and Make The Distinction Between Science and Politics

This issue does not depend on the idea of government telling you what you can do, or if you mistake being able to drive for some sort of liberty.
Do you recognize that if you light a candle in your house, the house is hotter immediately? Do you recognize that your house is NOT a closed system?

If your answer in either case is "no", I suggest that you have been brought into this argument by emotions, and that you have something to learn about heat. Please relax and consider the laws of thermodynamics before you continue. It is necessary to know something about them to make intelligent judgments; it is not necessary to know everything. In short, heat is not temperature. Heat is the transfer of energy due to a difference in temperature.

This issue is being screwed up by fighting over what to do about it, but the facts of the matter are not in doubt. Really.
However, you might not know how to figure out who is lying and who is not. This is pretty simple to figure out, if you can simply understand that heat flows from "hot" to "cold" because the "hot" area has more energy in it than the "cold" one.
Pictures of the Earth from space will show you cities. Lots and lots of cities. Expending energy, right on the surface of the earth.

So here's how that goes:
There are cities where there were none before.
Human population and energy usage grow over the years.
It is hotter in the cities.
It is that simple. Population is proportional to energy release into our living environment.

It doesn't matter what volcanoes or other natural forces do at all.
This is not debatable: our liberation of energy from chemical and nuclear sources occurs directly into our living environment. 
Part of this is direct radiation, and then we emit gases that were not there before we released them.

Do you know how to figure out how much water vapor and CO2 your car puts out? You should, if you want to understand human impact. Gasolines and diesel fuels are blends, and they also contain impurities, but they generally do these things: the carbon in a fuel molecule makes many CO2 molecules when burned, and the hydrogen in a fuel molecule makes many H2O molecules. You can derive many of the properties of gasoline as a fuel by observing this article.  Note that ~114 grams of fuel - about 1/4 pound - will combine with ~272 grams of O2 to make about 386 grams of exhaust vapor? In the process, your exhaust will release most of the heat of combustion to the air around you.
And one gallon of gas is about 24 times this amount of fuel.

Burn one gallon of gas, produce about 20 pounds of heated exhaust gases.

Now, look around you in traffic. Have you ever noticed that thirty cars making 30mpg burn one gallon to get one mile? I bet not. So you and thirty other people went to the convenience store a mile away, or drove a mile in traffic. Or drove less than a mile on the Interstate, in formation, at 80mph because 70 is inconvenient.
Did you notice it took mere minutes to burn that gas? So. Hundreds of millions of cars, buses and trucks are on the road worldwide. Ships and trains burn fuel, too - like trucks, their engines are a bit more efficient, especially newer models, but this is less than a factor of two - we're still in the ballpark.

So heated exhaust emissions are in the billions of pounds per minute category.

Take a look at this graphic. It shows the sources of energy and its usage in terms suitable for comparison. It also shows us something the layman might not recognize at all: rejected heat. You can think of this as the unused energy found in your hot exhaust gases - feel the tailpipe of your car. Realize that heating your exhaust pipe didn't push your car.

Look at the ratio of each of the Energy Services to Rejected Energy, and you will see that we:
• Lose more energy than we use;
• Lose more energy as a fraction of usage in "transportation" than anywhere else.
Think of millions of cars idling. That's waste, and that's where electric cars are going to save a great deal. The chart does NOT indicate exhaust gases, because the loss of energy occurs even in processes where gases are not emitted, like nuclear power electrical generation, AND it does not address direct heating of the environment by lighting, or building heaters.

Okay, now.
Two wrongs do not make a right.
If you were downwind of a factory that let off sulfur dioxide, you'd never tell them, "Hey, that's OK, volcanoes do that!"

You might have a hard time when some well-meaning duffer blames a severe thunderstorm, tornado or fish kill on "global warming". Hey - I do, too, because warming cannot be credited for an individual incident without investigation. That's not how it's done. You MUST show your work.
That said, a hurricane's wind is the product of a truly tiny differential pressure exerted across hundreds of miles of compressible medium. I bet you can't describe the mechanism, and I bet you don't deny that a hurricane is a real thing.

This issue does not depend on the idea of government telling you what you can do, or if you mistake being able to drive for some sort of liberty.

The laws of thermodynamics will have the final say here. You should know what they are - and realize that when you set fire to something, the fire is the hot part.