What if there was no naturally occurring ice on earth? What if the Greenland and Antarctica ice caps completely melted? What if the Arctic Ocean was ice free? What if there were no glaciers in Alaska, the Himalayas or elsewhere? Is this even possible? What kind of world would we have? Does this sound like a nightmare scenario? Interesting questions, right? But no, you say, these things could never happen. But they have. The world was a very different place when they did.

The Paleocene Epoch spanned from about 65 to 56 million years ago. This was a time just after the dinosaurs became extinct, when earth's land masses were moving to their present positions and temperatures were warmer than they are now. According to a recent article in National Geographic, an event of unprecedented magnitude occurred at the end of the Paleocene. This event is called the Paleocene-Eocene Thermal Maximum (PETM). A continuing large release of carbon into the atmosphere caused the earth to get warmer still, leading to the ice free conditions described above. Geologists estimate that the PETM lasted for about 150,000 years. The source and amount of carbon released is not specifically known, but some scientists speculate it would be equal to the amount that would be released if all of earth's known reserves of natural gas, oil, and coal were rapidly used.

This is not science fiction. What would happen if such an event took place now? First of all, it would be gradual, but let's say that it took place over 200 years. We could expect an average temperature rise of 9 degrees Fahrenheit worldwide. Doesn't seem like much, but trust me, it is. Imagine Washington, DC with three months straight of temperatures exceeding 100 degrees together with our humidity? Like palm trees? You'd have them in your yard. Imagine Las Vegas with temperatures exceeding 120 degrees. Whew!

But guess what? Temperature would be the least of our worries. Scientists have determined that the sea level during PETM was 220 feet higher than present. Imagine what the land surface would look like now. There'd be a lot less land. Water, water everywhere. Probably more than half the world's population would be displaced—Omaha might become the largest U.S. city. Sure, you could have an office in New York's Empire State Building but it would be above the 20th floor and only reachable by boat. Take Florida. Florida wouldn't exist except for a small island or two. Miami would be a new Atlantis. Take southern Asia. Most of Bangladesh, presently home to 160 million people, is less than 40 feet above sea level. Where would the people go?

We burn our reserves of fossil fuel and pump carbon into the atmosphere at astonishing rates. The PETM doesn't tell us what will happen if we continue, but instead gives us a perspective. The National Geographic article concludes, "…the whole pattern of life on Earth may be radically different from what it would otherwise have been – simply because of the way we powered our lives for a few centuries." Food for thought!

Please email your thoughts and ideas to: rengberg@verizon.net