Thursday, March 29, 2007

Global Warming--The Truth Revealed

Based on yesterday's Global Warming poll, it looks like some people need to catch up on the facts.

Here’s a short summary of what’s happening in the atmosphere. Carbon Dioxide molecules have 3 atoms: 1 carbon, 2 oxygen. This makes it a greenhouse gas. Gases with 3 molecules or more are greenhouse gases. Why do they have to have 3 atoms, you ask? 3 atoms make them just big enough to block stop radiation from leaving the atmosphere. To explain this, you need to know about the greenhouse effect.

Energy from the sun travels to Earth as electromagnetic waves. It first encounters the atmosphere. Some infrared radiation and most ultraviolet radiation are reflected by greenhouse gases in the atmosphere. Some of the rays are reflected by clouds, gases, or dust particles. The energy that gets past the atmosphere next encounters Earth’s surface. Some of it is reflected back into the atmosphere, while the rest is absorbed. When the surface is heated, it radiates some of the energy back into the atmosphere as infrared radiation. This radiation cannot escape back into space. Instead, much of it is absorbed by greenhouse gases. These gases, such as water vapor, carbon dioxide, nitrous oxide, and methane make life on Earth possible through this effect. This process by which gases hold heat in the air is called the greenhouse effect.

There is no question, even among global warming doubters, that burning fossil fuels releases CO2. CO2 is the biggest cause of the enhanced greenhouse effect, or man made global warming. Global warming doubters will say, “What about water vapor, the most common greenhouse gas?!” It is true that water vapor is the biggest cause of the natural greenhouse effect. Why doesn’t water vapor contribute to the enhanced greenhouse effect? Because of saturation. The air can only hold so much water. There is always the same amount of water on Earth because of this and because of the water cycle. Therefore, water vapor always contributes the same amount to the greenhouse effect no matter what.

More can be found at Thoughts on the World and a lot more can be found here.