Bear Flag Republic Radio Weblog

More on Sep 2004 National Geographic cover story on "Global warming". On page 25, the NGS writes that "In three decades the average temperature rose 4.16 degrees F" in Barrow, Alaska, 3.54 degrees F in Juneau and 2.26 degrees in Anchorage. The NGS does not provide a time frame for the "three decades" nor do they give a reference for the source of this information.

However, the data for this is obviously from tables and charts provided by the Alaska Climate Research Center for the period 1971 to 2000 which show the exact values quoted in the Geographic.

As you can see from their own larger climate history for Barrow, the early 1970's was a period of below normal temperatures in Barrow. By choosing this starting point, they manufacture a trend line that shows a large increase in average temperatue. Merely changing the starting period to the late 1960s results in a flat temperature trend. Look at the green line in the linked chart and you can see this for yourself.

The temperature trend in Anchorage makes this bloody obvious - take a look at the chart, beginning at 1970! The temperature trend between 1960 and 2000 is a straight line - they are exactly the same temperatures! But by starting at the very low temperatures in 1970, the temperature rise to 2000 looks dramatic.

Juneau has three official temperatue measuring stations (which was used? I do not know). One is identified as always running 1 to 4 degree warmer than the others, while another one shows a very flat trend. (Read the "station history" section for amusement and note that the thermometer was moved from 5 feet to 17 feet, as well as moved around a bit an unknown distance. Keep that in mind when you read about any temperature history as quite often, the official temperature for all locations was actually measured at different locations over time. Thermometers were replaced over time. Vegetation changed. Local buildings were added. Many things changed to influence the measurement. So the data is statistically manipulated to attemp to "correct" for all the changes that occur over time.)

Looking at the Global Mean Temperature shows this problem even more dramatically. 1971, the starting point for the trend line, was a very cool year, while the year 2000 was a warmer than normal year, just coming off the highs of 1998 and 1999. You can see the Global Mean Temperature chart here (Source: National Oceanic and Atmospheric Administration) - you need to divide the Y-axis value by 100 to provide a value in tenth of a degree Celsius. So where the chart shows -20, this means -.2 degrees Celsius.

If the temperature trend is narrowly measured between 1971 and 1998 or 1999, you can create a steeply sloped increasing temperature trend line. Starting at 1965 up to 1998, you can demonstrate a +1 degree C rise in global mean temperatures! But starting at 1960, the slope becomes a much smaller 0.0 to 0.2 degrees C upwards trend. See how easy it is to misuse statistics (even simple ones!) to prove potentially false conjecture?

Going back to the 1930s (remember the Dust Bowl in the U.S.?) would show a decreasing temperature line until the 1970s, and then a rise again (most all of which occurred in the 1970s only) up through 2000.

You can also manipulate the result by choosing the ending date for the curve. Why the year 2000 and not newer data for 2003 or even 2004? Possibly because the temperatures have been declining since 2000? I dunno but I am very suspicious. Teasing the detection of human influence on climate out of extraordinarly noisy, constantly flucuating, non-linear data is very challenging, to say the least.

We know that carbon dioxide levels have steadily increased. That's a fact. Some temperature measurements show a slight increase (some also show decreases, such as in most of Antarctica, or relatively flat temperatures, as measured by microwave sounders on satellites).

Scientists do not know why carbon dioxide levels have increased but have hypothesized that it is caused by human consumption fossil fuels. Since they have no way to test this hypothesis, they have created virtual worlds or computer models to simulate a world that operates the way they think it might (or might not as 75% of the primary variables are not well understood at all). They also have no way of knowing what future human behavior will be - including such fundamentals as the future world's population (which has been consistently overestimated and recently lowered), what fuels will be used in the future, what economies will be like in the future, and so on. So they guess about the future and create scenarios. This let's them play games of "what if?" based on changes in the variables they have identified. This is far from a certain science.

Sadly, formerly responsible publications like the NGS magazine neglect to inform their readers of the large uncertainties associated with global warming theories. The cover of the magazine features a forest fire, and the text inside suggests this is an early indicator of global warming. Absolute total nonsense. A forest fire today is not indicating global warming!

There are significant reasons for people to be very skeptical, and extremely skeptical of the worthless Kyoto Protocol (which does essentially nothing at very great cost).

The National Geographic has engaged in a sleight of hand to prove that human induced global warming is real. Misrepresentations of the temperature record, like what they have done are akin to cheating or fraud. I can find other mistakes in their article but why waste my time? It would be nice if the professionals would engage in skeptical - and honest - inquiry once in a while. The kind of sloppiness that appears now in National Geographic tarnishes the Geographc - to the point that I may not renew my "membership" (fancy name for a subscription).
[Edward Mitchell: Common Sense Technology]
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