Contributors

Friday, August 30, 2013

The Arrogance of Ignorance

There they go again. Todd Rokita, an Indiana Republican, recently said that humans can't possibly change the climate of the entire planet:
“I think it’s arrogant that we think as people that we can somehow change the climate of the whole earth when science is telling us that there’s a cycle to all this,” he said. “And that cycle was occurring before the industrial revolution and I suspect will occur way into the future.”
This is like saying that something the size of ant couldn't possibly tear down a house. Ants are just too small! Termites, however, can easily destroy houses.

It is not arrogant to think that humans can change the climate. It is the height of ignorance to think that we can do anything we damn well please without affecting the future of our of grandchildren.

The fact is, humans have been changing local climates for thousands of years. When you chop or burn down trees and convert forests to croplands, you change the climate.

You can see this for yourself: just take a bike ride down a trail in Minnesota on a hot day. When you're pedaling along a trail shaded by trees the air is cool and damp. When you leave the shade and enter a grassy area -- or a wheat field -- the air is dry and the temperature jumps several degrees. This is because forests cool the earth, and help to retain water locally instead of sending it all back into the air. Trees may even make it rain.

The effect is even greater when you replace trees with cities. This produces an effect called the "urban heat island." Areas denuded of foliage and covered with concrete and asphalt retain heat and and don't retain water, changing the local climate. Climate change deniers are well aware of this: they count on it to attempt to discredit historical climate data (which scientists have accounted for in their calculations).

Farmers in Brazil and Indonesia have been burning and chopping down the great rain forests for decades, turning lush, damp forests into dry fields. Haitians scavenging for wood to burn have chopped down all the trees on their side of the island. The American West has been hit hard by wildfires, and thousands of square miles have been burned in the last few years. This has changed the local climates, making them drier.

If you change enough local climates through deforestation and urbanization, pretty soon the continental and global climates change.

There are seven billion people on earth. Yes, there have been natural climate cycles in the past. But there have never been seven billion people before. The land area of the earth is 149 million square kilometers, or 58 million square miles. That gives us a population density of 121 people per square mile across the entire planet. By comparison, Macau has 73,000 people per square mile, India has 954, China has 365, Nicaragua has 120, the United States has 84, Alaska has 1.2. This means that, if we put our minds to it, we could easily chop or burn down all the forests in the world even with tools as primitive as stone axes. Which would drastically alter the global climate. And if you consider what would happen if we detonated all our nuclear weapons at once, it's clear that humanity has more than enough power to change the climate of the planet.

Over the past 200 years we have been digging up oil, gas and coal which were formed by the remains of forests and plants over millions and billions of years. Not only are we burning the forests of today and putting their carbon into the atmosphere, but by burning fossil fuels we are putting the carbon of millions of years of forest and plant growth into the atmosphere, all in the blink of an eye on the geological scale. It's like burning all the forests that ever existed all at once.

That is something that has never happened on earth before, so any talk of science's "natural cycles" goes completely out the window.

To think that that the activities of seven billion people can't change the climate is both arrogant and ignorant. So the question is: are we going to be termites, gnawing at the foundations of the world's climate until it comes crashing down upon us? Or are we going to be good shepherds of this earth?

No comments: