Turns out that in the U.S., 1934 was a bit hotter than 1998. Which matters not a whit for global temperatures, but it’s worth reading the story below before the spin machine gears up. Mr. Limbaugh has already started.

“1934, not 1998, the hottest year on record, NASA confirms,” from Greenwire ($ub req’d):

The hottest year on record in the United States was 1934 — not 1998 as had long been believed — NASA scientists announced this week.

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The change to the record books came about when Canada-based blogger Steve McIntyre of the blog Climateaudit.org e-mailed NASA earlier this month to point out an unusual jump in temperature data between 1999 and 2000.

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When agency scientists checked his question they found that two temperature history data sets that were incorrectly assumed to match were merged several years ago.

When the data was corrected it showed a decrease of 0.27 degrees Fahrenheit in yearly temperatures since 2000 and a smaller decrease in earlier years. That meant that 1998 went from being 0.02 degrees Fahrenheit warmer than 1934 to 0.04 degrees cooler.

The agency also reduced the mean U.S. temperature anomalies for the years 2000 to 2006 by 0.15 degrees Celsius.

The reranking of the hottest year in the United States does not affect world temperature records though, where 1998 is tied with 2005 as the hottest year ever, NASA climatologist Gavin Schmidt said. The data adjustment changes “the inconsequential bragging rights for certain years in the U.S.,” he said. But “global warming is a global issue, and the global numbers show that there is no question that the last five to 10 years have been the hottest period of the last century,” he added.

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With the new U.S. rankings, four of the 10 warmest years in the United States occurred during the 1930s.

“But in big-picture terms, the adjustments didn’t change anything for global warming or climate change issues,” Schmidt said. “The changes were pretty negligible” (Thomas H. Maugh III, Los Angeles Times, Aug. 15).

Radio show host Rush Limbaugh last week said the record adjustments are evidence that climate change science is unsound. “What do we have here? We have proof of man-made global warming. The man-made global warming is inside NASA … is in the scientific community with false data” (Daniel Dale, Toronto Star, Aug. 14).