Wednesday, September 5, 2007

Who or What Caused Global Warming

A short article about global warming, from:

Who or What Caused Global Warming
We are all familiar with Al Gore’s movie An Inconvenient Truth which argues that human-caused global warming will result in near-total destruction of the planet . We can excuse him as he is only a politician not a scientist. However, the Union of Concerned Scientists state unequivocally that they can identify the “Human Fingerprint” on global warming. Even the EPA blames global warming on human activity in their web site where the opening paragraph states: According to the National Academy of Sciences, the Earth’s surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades. There is new and stronger evidence that most of the warming over the last 50 years is attributable to human activities.

So, is global warming real, and if so, are humans to blame? The proof that is cited for a human cause of global warming, the “undeniable human fingerprint” comes from computer-based climate models. The problem is that for a computer-based climate model to be proof of anything, it would require that the scientist generating the model knows all of the variables that affect climate, and knows them so well, that no assumptions need to be made. Should the model fail to account for any variable or should the model contain any assumptions, then the validity of the results can, and should, be challenged.

Examine the following figures from Dr. Lee Gerhard in his web-based presentation, “Geologic Constraints on Global Climate Variability” and see if the models can stand up to the challenge. So, is Global Warming real?
Well, it is certainly warmer today than it was during the “Little Ice Age” of the late 1700s.
It is clearly warmer today than it was 20,000 years ago, but not as warm as it was 125,000 years ago.
And it is cooler today than it was during the “Roman Warm Event” of 500 BC or the “Medieval Climate Optimum” 1000 years ago.

Whether or not you believe we are warming or cooling, the debatable question according to Dr. Gerhard is “Do humans control earth’s dynamic climate system?” The principal cause of global warming according to the EPA and the Union of Concerned Scientists is increased amounts of CO2, which they argue is the result of industrialization. Yet if you examine the graph below, you will see several things. One, CO2 levels have both risen and fallen in cycles over time. These cycles existed long before the beginning of the industrial revolution, which would suggest that human activity is not responsible for CO2 cyclicity. Second, there is a several thousand year lag between the start of the temperature cycle and the CO2 cycle such that one might ask if the rise in temperatures is the cause for the rise in CO2 not the effect. It should be noted that a similar graph appears in the Woods Hole web site, however at a more compressed scale such that the lag is not apparent. They use the graph as proof of human induced global warming although they do not explain how human activity 350,000 years ago resulted in an increase in CO2. No wonder the public is confused.

So, if CO2 is not the cause of temperature changes, what is? Based on the graph below, one would conclude it is the sun.
Now there is a revolutionary concept; solar activity affects the Earth’s temperature. I wonder how Al Gore missed that one!

Finally, let me offer one last picture – proof of global warming. It illustrates nicely the effect on humans, not the affect of humans. More importantly, I hope it leaves you with a smile.
For more information on the truth and lies behind the global warming issue, I would encourage you to read “State of Fear” by Michael Crichton; an excellent thriller with abundant footnoted facts about climate change. You are also encouraged to visit Lee Gerhard’s excellent web-site. Other interesting web sites, both informative and alarmist are listed below.

Informational Sites
Kansas Energy Information Network
Geologic Constraints on Global Climate Variability
Competitive Enterprise Institute
National Oceanic and Atmospheric Administration

Alarmist Sites
U.S. Environmental Protection Agency
Union of Concerned Scientists
Woods Hole Research Center

1 comment:

global warming fearful said...

Interesting perspective on a "hot" topic. One particularly difficult aspect of global warming worth noting is that mosquitos (yeah, those that carry dangerous viruses like West Nile) both breed more readily and more readily pick up dangerous viruses in hotter weather. Thanks for this interesting and informative blog.