Raw Temperatures

In my poking about trying to get a grip on the debate about global warming, I've tried several times to get raw temperature data. Until this morning, I've always failed -- all I've been able to find is the "adjusted" data, and the adjustment methods are opaque. I'm suspicious when I see something this; it makes me think there's something there the authors don't want me to see.

So I was delighted this morning to uncover this graph of raw temperature data -- and of California, no less! You can click on it to get a full-sized, readable view. I found it at this web site, along with this description of how the data was gathered:

Today I visited my friend Jim Goodridge, former California State Climatologist and the man with a garage full of data going back to before the Gold Rush.

He’s been quietly toiling away in his retirement on his computer for the last 15 years or so making all sort of data comparisons. He gave me two CD ROMS full of data that I’m just now wading through. One plot which he shared with me today is a 104 year plot map of California showing station trends after painstakingly hand entering data into an Excel spreadsheet and plotting slopes of the data to produce trend dots.

He used every good continuous piece of data he could get his hands on, no adjusted data like the climate miodelers use, only raw from Cooperative Observing Stations, CDF stations, Weather Service Offices’s and Municipal stations.

Nothing but the data, ma'am. Just good, clean, raw data. And it is fascinating to examine.

If you're unfamiliar with this particular method of plotting data, here's the key point: the biggest red dots represent the largest temperature increases, and the biggest blue dots represent the largest temperature decreases (both over the 104 years of data). As the author points out, there's a definite pattern there -- the red dots are clustered around major population centers (Los Angeles, San Francisco, San Diego, etc.) and the blue dots are, well, nearly everywhere else.

One of the frequently heard claims of the global warming skeptics is that the data used by the global warming proponents is biased by the "urban island" effect -- a well-known phenomena wherein cities are warmer than their surroundings. The reasons for this are many, but they boil down to the predominance of man-made materials in a city (concrete, asphalt, etc.) over the plants (trees, grass, crops) found around them -- and where the city is, before the city was built.

It sure looks like this raw data supports that that claim. If you were to subtract the populated areas from this chart, the trend would be toward a mild cooling! This single compilation of data, however compelling, is a long way from scientifically credible proof -- but it certainly doesn't decrease my skepticism about the global warming "phenomenon"...