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Is Global Warming a Hoax?

Tue ,10/05/2011

Sen. James Inhofe (R –OK) is famous for his statement, “Global warming is a hoax”. The local Tulsa newspaper often carries letters giving the opposing viewpoint. For example, Corey Cohen, recently wrote, “Sen. Inhofe, please cease your effort to stop EPA’s ability to limit greenhouse gas emissions. The science of global warming and climate change is obvious and known. For example, excessive CO2 in the atmosphere absorbs heat reflected from the ground and traps that heat in the atmosphere, melting glaciers and ice and snow packs all around the planet. A given molecule of CO2 in the atmosphere has a life of approximately 100 years. The implications are fairly obvious: rising sea levels, loss of fresh water for humans and unpredictable growing seasons for Oklahoma farmers and their winter wheat crops due to atmospheric heating.” (1)

Mr. Jack Williams replied (2) by “pointing out a few facts”  to defend Senator Inhofe’s position:

“1. More than 31,000 scientists signed a petition opposing the concept of man-made global warming.

2. More than 100 top climate scientists have expressed their opposition.

3. A dozen recognized scientists from nine countries who initially were global-warming proponents have changed their opinion and now oppose it in light of recently published information.

4. Earth has undergone many cooling and warming periods during its history.

5. Carbon dioxide constitutes less than 0.1 percent of the atmosphere while water vapor, at least as effective a greenhouse gas as CO2, ranges from about 20 to 100 times its concentration, and is quite variable.

6. There has been no measurable increase in global temperatures during the past decade.

7. The polar bear population dramatically increased during the past decade, as has ice thickness on Antarctica.”

It’s always nice to get alleged facts in a numbered list, where it is possible to check them one by one.

Endorsements: Facts one, two and three, fall into  the category of endorsements, and as with many endorsement, it is not always clear how well qualified those who endorse the position are, or whether the numbers listed are significant. There are about 23 million graduates with degrees in science and engineering. If 31,000 scientists signed the Oregon Petition, that is about 0.13% of those – hardly significant. Even then, the petition appears to be a hoax. In 1989, the Petition was mailed to thousands of Bachelor of Science students. It was formatted to appear as if it came from the National Academy of Science, but the organization quickly responded that the information was misleading and “the petition does not reflect the conclusions of expert reports of the Academy.”  The mailing collected 17,000 signatures and 14,000 have been added since. Most anyone could sign it, many who signed were misled, and many were not scientists at all, as it is possible to get BS degrees in fields such as journalism, sociology, education, philosophy… (3)

Endorsements that matter: All the major scientific organizations in the world have endorsed a statement such as that of the American Chemical Society,  “Careful and comprehensive scientific assessments have clearly demonstrated that the Earth’s climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles. There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change.” (4) A recent CNN poll found that 97% of scientists who are actively engaged in research in climate science agree that global warming is caused by man. (5) There is clearly a consensus among scientists on the matter and those making policy would be wise to heed it.

Warming and Cooling: Point four is a fact, but it is not relevant to what is happening today. The Earth has in the past had many natural warming and cooling periods but the current warming trend is not part of those. In the  past, ice ages and warmer interglacial periods have occurred in roughly 100,000-year cycles. These are attributed to the Milankovitch cycles. These cycles are small variations in the eccentricity, axial tilt, and precession of the Earth’s orbit that cause the amount of sunlight the Earth receives to increase and decrease in predictable cycles The cycles predict that a slow cooling trend, which began some 6,000 years ago, will continue for the next 23,000 years. The current warming trend is too rapid and in the wrong direction for the Milankovitch Cycles to be the cause. (6)

Greenhouse gases: Point five is also a fact, but it incorrectly downplays the role of  CO2  in determining the Earth’s temperature. In 1956, G.N. Plass calculated (7) that doubling the concentration of CO2 in the air would cause a 3 to 4 C increase in the Earth’s temperature. Many dismissed his work, as it seemed impossible that CO2, which made up only 0.03% of the air, could have such a large effect on temperature.   However, in 1997, J.T. Kiehl found (8) that, under clear sky conditions, CO2 accounted for 26% of the greenhouse effect – with water vapor accounting for most of the rest. More recent research (9) has confirmed their work, and CO2 has been labeled the “Control Knob” for the Earth’s temperature.  Recent research in the Journal of Climate, covering the last five ice ages, has experimentally confirmed Plass’ work. The Earth is warming because of the greenhouse gases we emit, and research finds the increase in CO2 is the main cause.

Temperature record: Fact six is based on the idea that 1998 was so hot, it couldn’t have been hotter since. However, NASA’s temperature record shows that 2005 and 2010 are tied for the warmest year on record and the last decade has been the hottest in recorded history – and the trend is yet upward (10). There have been attempts to discredit NASA’s temperature data by challenging the accuracy of the temperature recording stations, but a study of that issue by the American Geophysical Union found that claim to be false. (11) NASA has put men on the Moon and brought them home safely, and they certainly should be able to measure temperatures on the Earth correctly.

Polar Bears:  It’s true that the Polar bear population has increased, but not because the Polar ice is increasing. The bears were hunted nearly to extinction, and their population is increasing because restrictions were placed on hunting them from aircraft . Recently, Polar bears have been put on the threatened species list, not because of their numbers, but because their habitat is disappearing.  Satellite measurements of the Arctic sea ice have shown that both the volume and extent of the sea ice has decreased remarkably over the last 30 years. (12) Polar bears are uniquely adapted to live and hunt on the Arctic Sea ice. As it disappears, so will the Polar bears.

Claiming something as “fact” does not make it so. And, even facts can be misleading if the inferences drawn from them are in error.  If Senator Inhofe bases his position on facts such as those listed by Mr. Williams, it is easy to see why he incorrectly thinks global warming is a hoax.

(1)http://www.tulsaworld.com/opinion/article.aspx?subjectid=62&articleid=20110313_222_G2_CUTLIN933913

(2)http://www.tulsaworld.com/opinion/article.aspx?subjectid=62&articleid=20110403_62_G2_InhisM784632

(3) http://jcmooreonline.com/2010/01/29/the-oregon-petition-how-can-31000-scientists-be-wrong/

(4) http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change#General_science

(5) http://articles.cnn.com/2009-01-19/world/eco.globalwarmingsurvey_1_global-warming-climate-science-human-activity

(6) http://jcmooreonline.com/2010/12/31/science-global-warming-and-the-ice-age-mystery/

(7) http://www.aip.org/history/climate/co2.htm#M_25_

(8) http://journals.ametsoc.org/doi/abs/10.1175/1520-0477%281997%29078%3C0197:EAGMEB%3E2.0.CO;2

(9) http://www.sciencemag.org/content/330/6002/356.abstract

(10) http://data.giss.nasa.gov/gistemp/2010november/fig2.gif

(11)http://www.agu.org/pubs/crossref/2010/2009JD013094.shtml

(12) http://climateprogress.org/wp-content/uploads/2011/01/NSIDC-12-10.gif

(c) 2011 J.C. Moore

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