II. The Greenhouse Effect


Carbon dioxide is a big deal because it is a very unusual gas and can have a big effect even in small quantities (like 400 parts per million). The big deal is this: sunlight is not heat, it is light energy. It becomes heat when it hits something that doesn’t completely (almost) reflect it (like snow). Any other color (black being the worst) and the light is not reflected and so warms the material.

Science runs on a very few basic absolute immutable laws, usually what are called ”conservation laws.” This means the energy in the light, if it is not reflected has to stay as energy and so it starts to make the molecules in whatever it hits move faster. So they get the energy, and the motion of the molecules is heat. So sunlight warms the earth. Without it there would be no life. Just ice.

It traps the heat like a blanket. The right abount of carbon dioxide (which got worked out over a few million years) and the earth is comfortable. The right amount is about 270 ppm.

If you look at Figure 3 (just over the earthrise picture) you can see that about 1850, just when the steam engine was invented, the amount of CO2 humans put into the air started to rise, and then started to rise more and more rapidly. Technology builds all sorts of great things like power plants and cars and they all spew CO2. Over 38 BILLIOON metric tonnes in 2015. That is a staggeromg amount and by then the CO2 was about 400 ppm. Today (30 12 2019) if is over 415 ppm and rising. So what does a staggering amound of CO2 do. It traps enough heat to raise the temperature of the earth (air, water, gound) about 1°C or 1.7°F, which does not seem like a big deal but it amounts to about 1,000,000,000,000,000,000,000,000 joules. The problem is that there is a lot of land, ocean and atmosphere to warm up. So everything gets a little warmer. But storms are big to so a little warmer sea, air, and land plus more humidity and you have what happened to Houston and the Bahamas. True catastrophe.

And CO2 hangs round for a thousand years or so and keeps warming. Then the cruncher. Warmer earth melts tundra which then gives off methane (see Fig 4 the burning snow). Methane doesn’t hang around so long (30 years or so) but it is about 30 times as good a blanket as carbon dioxide and I could not exaggerate how big a problem that is. It is a time bomb. As soon as enough melting of the tundra happens global warming becomes self-sustaining, it doesn’t need us anymore and we can no longer stop it. And we are on the edge of that waterfall at the very top.

And that is why Figure 3 shows the blue band of “negative emissions” which means taking the atmosphere to the carbon laundry and removing carbon from the air.

And so we come to the crux of the issue. No one knows exactly when the bomb will go off, but we are so close that we cannot take any chances yet the entire world is mostly ignoring the problem. When we should be following the red down line, we are following the business as usual line.

Add to that that killing emissions (see below) and scrubbing the air (see below will cost trillions of dollars. Then add to that that hardly one understands this long story, the oil companies just ignore it, and President Trump says that it is all hooey.

From my perspective it is a Perfect Storm. Everything that could go wrong (almost) is going wrong and the only way out is superman or superwoman as President of the United States. No one else could wield the influence to break this dreadful dead-lock. Vote Climate.

On the way to 1.5°C.
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