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Climate Change Information Update

A few items were made available recently that provide additional information regarding global climate change.

In the last month, much has been made about the cooling recording in January. Delayers have used this data to claim that there is global cooling, not warming going on. If only they didn’t react to every single datum that came out, they might be able to build a coherent argument. But let’s stick with the data, shall we? Both NASA and the Hadley Center‘s analysis show that global temperatures in 2007 remained high: NASA listed 2007 as the second warmest on record, behind 2005, and the Hadley center listed 2007 as the seventh warmest. And before someone comes along and tries to argue that the difference in rankings prove something, both centers’ data show a difference of less than 0.5C between the first and tenth warmest year. The point is that 2007 was among the warmest in the last 100+ years.

Which brings us to January of this year. Embedded within the 2007 temperature data is the following: it was actually characterized by a strong La Nina event. La Nina is the cooler portion of ENSO. That’s right: global temperatures, even under the influence of a major ocean temperature cooling phenomenon, were still among the warmest recorded: almost as warm as the extreme El Nino event of 1998. By January, the La Nina event was in its mature stage. Here’s where the delayers’ argument comes in: January 2008 was much cooler than January 2007. Instead of a +0.632C anomaly in Jan. 2007, Jan. 2008 had a +0.037C anomaly.

Hmm, that’s interesting. Anomaly compared to what? Every dataset they’re examining uses mid-20th century data as a baseline, which is fine, or doesn’t consider the entire globe, which isn’t fine. Temperature data at the poles are critical for understanding what the global change of temperature is doing. This is especially true when one realizes that most of the temperature changes we’ve recorded have occurred in the polar regions. Most mid-latitude locations haven’t recorded the same magnitude of warming that the poles have (normalized differences are very large at the poles, thus you’ll rarely, if ever, see delayers use them as a data source).

So if 2007 was among the warmest years recorded and a strong La Nina developed during the year, what kind of temperature anomalies will we see during the next strong El Nino? And what lame excuse will delayers come up with to try to explain it away?

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