Archive for the ‘Global warming’ Category

On Climate Change, and Wringing of Hands

August 14, 2016

We’ve been changing the climate since we first crawled down from the trees.
And promptly began cutting them down.
Instead of shade, the sunlight went directly to the ground. Re-radiated heat was captured by water vapor, carbon dioxide, and methane. But there were still plenty of trees, billions of them, so no one noticed.
We built cities. No one knew there was a ‘heat island’ effect. After all, there were still hundreds of millions of trees. The heat island effect wouldn’t be discovered for a few thousand years. Why worry?
We paved over the ground. No one paid attention. Any fool knows better than to walk barefoot on a macadamized highway in the summer; if he forgets, there are blisters to remind him. But there were millions of trees still remaining, so no one noticed.
The deserts grew larger. There had once been trees there, but they had been cut. The rains no longer came. The forest became productive farmlands, which in time became a place called the Sahara. But no one understood, because there were still millions of other trees.
The fossilized remnants of billions of trees, of trillions of tiny plants, were mined and pumped out. Finally, people began paying attention.
There were still a few trees, after all.
But the forests are vanishing. More people need cars, which need more oil, gas, and coal to provide power for them and for the houses. Instead of billions of trees, we have billions of people.
Who are still doing precisely what that first ancestor did, put pressure on the climate.
We could begin planting trees. Trees take carbon from the atmosphere and shade the surface, meaning there’s less energy to be transferred by infrared radiation, which in turn means a reduced greenhouse effect.
But no, all those people need food. Food production takes a lot of land, so we can’t plant trees there. The food needs roads and highways to bring it to the cities where the people live. In their own heat island. Where trees have been cut down to make room for ever higher buildings. To make room for ever greater numbers of people. In an ever-growing heat island. Which is served by more and more highways that absorb solar energy and re-radiate it to the atmosphere, where carbon dioxide, methane, and water vapor capture it. In the process we call the greenhouse effect.
How nice! We now know about the greenhouse effect, about heat islands. We have NAMES! Not solutions, but at least we know what’s threatening our world.
The simplest solution, long term, is to plant more trees and let them grow until they’re old. But no; poor people will cut them down and sell the wood for lumber,  or burn it to keep their houses warm and cook their food.
An almost-as-simple solution is to put reflectors alongside all those miles of highway and on all those heat-island roofs. Reflectors send incoming radiation directly back to space, instead of allowing it to be absorbed by the atmosphere.
But that’s ridiculous. Line highways with cheap reflector panels made from sheets of mirror-finished Mylar? Sure, the reflectors would be cheap, but that’s too simple. It would cut down on the greenhouse effect by preventing surface heating, BEFORE the heat is re-radiated and captured by the atmosphere.
Why don’t we wring our hands instead?