Thursday, July 06, 2006

Dr. Gore, Please Call Your Office

By now we have all heard of Dr. Gore's dire predictions regarding global warming. You remember Dr. Gore, right? He was the inventor of the internet, a French scholar at 15 while plowing hillsides in Eastern Tennessee, a consultant to the author of the best selling novel and eventual movie, Love Story, and was once even the President of the United States (Senate).

I'll concede that the earth's annual average temperature has indeed risen during my lifetime. I won't even bother to argue the difference in quality and precision of temperature measuring equipment and data keeping between the mid 1950s and now. Just accept the stated 1/2 degree Fahrenheit temperature rise as accurate. For the purposes of this article I won't even use the current argument of my fellow conservatives, (and the same one I used to use on my Mom), "I didn't do it!".

No, for now let's take Dr. Gore at his word. The Earth is getting hotter, and we are causing it. It seems his theory is that we, by continually pumping Carbon Dioxide into the atmosphere, are causing more and more of the Sun's energy to be retained instead of being reflected back out into space. It's getting scary, ain't it?

I've been able to hold back and not really get into this hysteria until now. I recently came across a link in the Virginia blog community to an article in the Sunday Los Angeles Times. The first paragraph of the linked Times article, based on Dr. Gore's recent movie, says; "The Greenland ice sheet - two miles thick and broad enough to blanket an area the size of Mexico shapes the world's weather, matched in influence by only Antarctica in the Southern Hemisphere."

Well, let's stop right there for a moment. Greenland certainly does have an ice sheet, but it's not two miles thick. According to the Encyclopedia Britannica it does reach thicknesses of over 10,000 feet (almost two miles), but it averages less than a mile thick at 5,000 feet. Also, it's area is considerably smaller than Mexico. Coming in at 669,064 square miles as opposed Mexico's 780,000 square miles. Now that's still a big chunk of ice. But not quite as big as Dr. Gore exaggerated it.

Later in the article it is stated that; "Should all of the ice sheet ever thaw, the meltwater could raise sea level 21 feet and swamp the world's coastal cities, home to a billion people."

Let's go back up to the figures I noted above when correcting Dr. Gore's initial error. Using those figures I come to this conclusion. 669,064 square miles of ice that averages .94 miles thick equals 5,353,248,505,651,200,000.00 cubic feet of ice. Now as an engineer of sorts I use numbers every day. But I don't work with numbers that large. I know that once you've used 4 commas in a number you are getting into the trillions, I don't know what you call a number with 6 commas. It's a big ol' number is descriptive enough for this article. What it really means is, like I said before, that's a bunch of ice. But, if it were to all be melted it would raise the ocean level by 16.4 feet, not 21.

But even that little math error is not the purpose of this article. I think we all can agree that a large amount of ice, which if melted could raise the ocean level by 16 feet, if not 21 feet is still a heck of a lot of ice.

Instead of looking at that ice as melted water, let's look at what it takes to melt that much ice. A BTU, (British Thermal Unit), is the amount of energy required to raise the temperature of one pound of water one degree Fahrenheit. Our Sun presents each square foot of the Earth's surface with 3.412 BTUs per hour.

Allow me to stop here just a moment and discuss Greenland's climate. The CIA factbook lists it only as "arctic to subarctic; cool summers, cold winters" so I had to dig a little deeper to find that the current yearly average temperature in Greenland is a very low 12.2 degrees Fahrenheit. I found further that the temperature only goes above freezing (barely) for three months out of each year (June to August). You could say that Greenland has two seasons. "Winter" and "Winter will be back in a minute". I'll be generous and allow Dr. Gore to claim the tons of ice (did I mention that Greenland has a whole lotta ice?) maintains a fairly uniform temperature of 20 degrees during both seasons. We both know it doesn't, in reality it's certainly much lower, but it will make my math easier, and for this exercize it serendipitously works out to fit Dr. Gore's ten year disaster plan.

I mentioned earlier that the Earth receives 3.412 BTUs of energy per square foot per hour. Again, let's be very generous to Dr. Gore and assume that we achieve 100% efficiency from those three BTUs. Extremely oversimplified (and nowhere near accurate) that would mean that for every hour of sunlight we would raise the surface temperature of the ice by one degree Fahrenheit. After an initial 13 hours of 100% efficiency sunlight, and no outside influences such as the second law of thermodynamics, the effect of ambient air temperature, and the inevitable darkness, we would begin to melt the ice on Greenland. In nine and a half years of continuous unabated sunshine, Greenland would become a rocky barren wasteland as opposed to the icy barren wasteland it is now.

Now, we all know it is impossible to achieve 100% efficiency from sunlight alone, even if we ignore the laws of physics as we did in the previous paragraph. And there is no way a mere one degree per hundred years average annual temperature rise can help offset those laws of physics which we just ignored in less than ten years. Dr. Gore's prediction that the Greenland ice cap may melt completely in ten years, as scary as it is to folks in Virginia Beach, is complete and unadulterated horse hockey.

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