March 19, 2009

"pimple on a gnat's bum."

Man a late entry in global warming/cooling cycles

by Lee Mossel

As a geologist, I take a REALLY long view of the earth's history. I like to put the current furor over global warming, or cooling, in the perspective of history...the earth's history.

The current "debate" has been going on for, maybe, 35 years but let's be generous and call it 46 years because that's going to make the following math easier. The earth is about 4.6 billion years old. (That's 4,600,000,000!) So, we've been debating global warming for 0.000001 % of the earth's history. Man, or at least our earliest demonstrable "human" ancestors, showed up about 2.3 million years ago. (That's 2,300,000.) So, "man" has been an observer of climate change for 0.05 % of the earth's history. {I will include some references at the end of this article.}

"Ice ages" and, conversely, the intervening periods of global warming have been occurring periodically but erratically throughout geologic time from about 3.3 billion years ago or about 1 billion years after the earth formed. This means that the first "global warming" period started with the BIG BANG and lasted about 1 billion years. At least 2 multi million year long ice ages occurred before the first signs of organic, carbon based life in the form of algae or pond scum. At least 4 more ice ages occurred from the age of pond scum, through the age of creepy crawlers, fishes, amphibians, reptiles (dinosaurs) and early mammals. In the last 1 million years, during the age of man, at least 10 well documented ice ages have occurred. The last "Ice Age", and that's a nebulous term, lasted a total of about 60,000 years from 70,000 years ago until about 10,000 years ago. In North America, the timing and duration are determined by measuring the advance and retreat of glaciers. Within the overall "Ice Age", there are also shorter periods of warming and cooling. The warmer periods, in today's vernacular, would be called "global warming."

Regardless of the histrionics and hysteria on both sides of the current global warming/climate change debate, the FACTS, as represented in the rock and fossil record, clearly demonstrate that the earth warms and cools over long periods of time.

Without question, man's use of fire, dating from 1.5 million years ago and, more recently, coal, dating from about 3000 years ago, and oil and gas for the last 150 years contributed to the most recent cycle of warming. At worst, however, it looks to have "speeded up" the earth's natural cycles by only a few decades. Let's be generous, again, and say that it started speeding up when we first burned petroleum about 150 years ago. That means that man's "contribution" has affected 0.0000033 % of the earth's history; 0.0065 % of man's history; and 1.5 % of the time since the end of the last Ice Age. Mounting evidence suggests that warming MAY have peaked in the 1970s and we MAY actually be returning to a cooling phase.

Again, regardless of the rhetoric on either side of the argument, most of which is advanced by politicians and non scientists, man's total contribution to overall world wide climate change amounts to far less than the proverbial "pimple on a gnat's bum." Even if ALL of man's "contribution" were to cease immediately, the net effect on the timing of global warming OR COOLING, basically, is not measurable in the context of earth's natural cycles.

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