Eureka! Greenhouse gas is good.
Our atmosphere is made up of approximately 20% oxygen, 78% Nitrogen, 0.93% Argon and 0.04% Carbon Dioxide - a greenhouse gas. Go outside close your eyes and think back 100,000 years. Now open them. What do you see? It would be warmer, there would be few trees and you would see Giant Sloths the size of modern elephants, as well as camels, wooly rhino and mammoths, and more. Can you imagine what millions of these animals would do to the trees? Tearing them down and pushing them over, and eating them all? I have come to the conclusion that there is not enough CO2 - greenhouse gas - in the atmosphere and man has indeed affected global temperatures by causing the ICE AGE. Over the years I have been in both camps concerning Global Warming, and have seen enough information to say that it is a natural cycle to man being the cause. My "eureka" moment came while watching an interview of a Russian scientist in Siberia who said that trees are the number one scrubber of CO2. Before man, there were fewer trees on the planet than there is today. Mankind hunted the megafauna like giant sloths, wooly rhino, camels and wooly mammoths to extinction (Take note that they were megaherbivores - they consumed grass and trees). Without millions of megaherbivores keeping trees under control, huge forests grew and covered the globe that caused CO2 to drop that caused then global cooling hence the Ice age. Killing a giant sloth or other slow moving megafauna would be easy. A hunter would run up with spear stab the animal in the gut pierce an intestine and follow it around for a week until it sickened with infection and easily finish it off. I surmise prehistoric family group could kill 20 megafaunas a year, with the animals slow reproduction rates extinction was inevitable. When man is not an efficient predator, animals reproduce in huge numbers. My first example where man without horses or firearms was not an efficient predator; fast mega-fauna like the American bison. On the open plains, an estimated 70 million Bison were alive when Europeans arrived in North America. This is no longer the case. Another example of man not being an efficient predator of megafauna is in Africa where trypanosomiasis (sleeping sickness) and malaria in non-tsetse fly tropical areas cause high human mortality due to diseases which kept man from hunting megafauna such as the elephant and rhino to extinction. The rise of man, the super predator, coincided with megafauna extinction and a global glacial epoch. Evidence of previous ice ages was destroyed by following ice ages so then evidence of other ice ages is limited. The most recent glaciation period, often known simply as the “Ice Age,” reached peak conditions some 18,000 years ago before giving way to the interglacial Holocene epoch 11,700 years ago. At the height of the recent glaciation, the ice grew to more than 12,000 feet thick as sheets spread across Canada, Scandinavia, Russia and South America. Corresponding sea levels plunged more than 400 feet. Other theories to other Glaciation is variations in Earth's orbit (Milankovitch cycles), variations in the Sun's energy output, and Volcanism. One may ask, "Why did it warm up if the megafauna is gone?" The answer lies mankind's deforestation for agriculture and fuel. This is why we are not in a Ice Age now. In conclusion: Global warming is good and natural for the planet. The tropics would not see a huge increase in temperatures because they only receive 12 hours of sun a day verses higher latitudes receive much more sun light during Summertime. Shrinking of the arctic circles would result in more habitable space but rising see levels will be a downs side. In the end it will be a net gain for humanity. Thank You. Brian K Smeester