Greenhouse Effect Gone Wild
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If you think that's it's hot today because of the Greenhouse Effect, just consider that.several billion years ago, the Greenhouse Effect had oceans boiling! Hi, I'm Dave Thurlow, and this is the Weather Notebook.

Greenhouse gasses in the atmosphere act like glass by allowing the suns energy in, but not letting the earth's warmth back out. Without it, the planet would be around zero degrees Fahrenheit. The greenhouse effect keeps the earth inhabitable presently, but that hasn't always been the case.

Shortly after the earth pulled itself together from a collection of space rocks and space gasses lurking about the new-born sun--about four and a half billion years ago--the Greenhouse Effect was out of control. The atmosphere then was almost 90 percent carbon dioxide, one of the more effective greenhouse gasses. This kept the young planet's temperature well above the boiling point, maybe even at times in the thousands of degrees! The atmosphere resembled a steam bath. The oceans were much more massive than today and repeatedly vaporized and condensed.. Storms roared across what little landscape there was with winds near a thousand miles per hour. It was out of control! What was the planet to do?

After a couple billion years of this craziness, along with the regular bombardment of asteroids, comets, and little planets, the carbon dioxidelevels started to drop and the greenhouse effect became less effective. Why? Because of life. That's right. Simple organisms in the ocean, through the process of photosynthesis, started to eat carbon dioxide and belch out oxygen. The high levels of carbon dioxide in the atmosphere dropped from more than 90 percent to the few 10,000ths of a percent we find today. And just that tiny amount gives us livable coolness, instead of the hadean heat in the greenhouse gone wild of the new-born planet.