Dueling Temperature Charts, But Where’s the Data?

Steve wrote here about the global temperature chart that presented conventional data in a normal way, and therefore aroused the ire of climate alarmists, who deemed the graph “misleading” because it didn’t look scary enough:


At Watts Up With That?, Dr. C. R. Dickson reviews the controversy over the chart:

This graph supposedly hides global warming because the small increases in temperatures aren’t obvious. An online article in The Huffington Post stated it was an improper visualization that makes “just about anything seem stagnant,” and The Fix at The Washington Post complained that “it is misleading” because it “hides the actual change in temperatures.” Also online, Business Insider said the graph zooms “out so much that it makes it seem like global average temperatures haven’t changed at all.”

Dickson puts two charts side by side, one showing temperatures, the other showing temperature anomalies, from a presumed base*, on a very small scale so that purported changes are greatly magnified:


A fundamental problem is that the alleged changes that are depicted in magnified form are in fact minute in relation to the uncertainty that goes into their measurement and calculation. The original includes links:

Because it’s so difficult to observe man-made global warming, some experts at NASA GISS believe the accuracy of climate models requires a one hundredfold increase in order to see the small amount of warming.

“A doubling in atmospheric carbon dioxide (CO2), predicted to take place in the next 50 to 100 years, is expected to change the radiation balance at the surface by only about 2 percent. If a 2 percent change is that important, then a climate model to be useful must be accurate to something like 0.25%. Thus today’s models must be improved by about a hundredfold in accuracy, a very challenging task.”

A paper by Graeme Stephens et al. in Nature Geoscience also shows how hard it is to find global warming. They reported the uncertainty in the earth’s warming imbalance as 0.6 watts per m2 ± 17 watts per m2. The enormously large uncertainty in this very small number means that it is difficult, if not impossible, to observe. Just like NASA said it was!

But how small is this imbalance? It’s only 0.06 percent of the 1,000 watts per m2 of sunlight falling on the earth’s surface at noon. …

Small numbers with large error bars, combined with excessive averaging, is a recipe for ambiguous results. The reaction to the temperature graph is a perfect example of how political motivations can twist ambiguities into disagreements. Confusion is created by using temperature as if it were the same as an anomaly, but somehow the temperature graph is misleading while the anomaly graph is not. What is hidden is the fact that both graphs display no real temperature data.

Good point! Not only that, the “data” keep jumping around, as Dickson notes:

The NASA GISS tabulated values were updated in the process of making the above graphs. A large number of historical values were changed without explanation making the tabulated values a moving target.

As we have pointed out many times, alarmists control the surface temperature record, and they keep changing it–altering temperature readings that were actually reported at the time–in order to make their theory appear more plausible.

There is much more to be said, but the controversy over the charts illuminates several aspects of the global warming story.

*Dickson explains the “anomaly” that is conventionally depicted:

To create temperature anomalies NASA GISS takes real-world temperatures and subtracts a subjective “best estimate for the global mean for 1951-1980,” which is calculated to be 14 degrees Celsius, or 52.7 degrees Fahrenheit. The temperature changes (ΔT) for both graphs are the same because one graph is offset from the other by a constant 52.7 degrees F.

Does anyone seriously believe that the “global mean temperature” for 1951-1980 is known to within a tenth of a degree Fahrenheit? I don’t think so.


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