So Many Thermometers, So Little Time

GHCN Stations by Geography and Age

GHCN Stations by Geography and Age

Full size image at: Wikipedia

It sure looks to me like we are trying to predict world climate based on very short temperature records for most of the world surface. Outside the U.S.A., Europe, and Japan the record gets pretty sparse and short…

How do you even detect 200 year patterns with this history?

About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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9 Responses to So Many Thermometers, So Little Time

  1. H.R says:

    Worse yet, as you and others have posted elswhere, temperature isn’t climate. We have sparse, unreliable data being used to describe “world climate.”

    From my perspective, earth’s climate switches back and forth between snowball earth and a lovely warm vacation planet somewhere in the universe. The last several million years of glacials and interglacials are just global weather. But most people don’t see it that way so for better or for worse we’re back to temperature.

    However, I still don’t see temperature as an accurate description of climate. The Pacific Northwest has a wet climate with moderate temperatures. The tropics have a warm, moist climate. The deserts have a hot, dry climate. The poles are cold and arid. I suspect the average Joe or Jane would discuss temperature AND rainfall when talking about climate and yet some of the brightest of minds, for reaqsons that escape me, have decided that global air temperature is the best indicator of global climate.

    I say, “Nope. Try something else, please.”

    P.S. What are the posting rules of the road here?

  2. Jeff Alberts says:

    Actually the Pacific Northwest has a dry climate as well. Seattle gets less annual precipitation than Dallas. And where I’m located about 70 miles north of Seattle we get about 1/3 less. There are some regions in Washington State at least that get a lot of rainfall, but they’re not the norm. East of the Cascades it’s more like the plains, hotter in summer, colder in winter, some desert-like areas…

  3. Jeff Alberts says:

    I agree on the lack of temp reporting stations, and the lack of more complete weather data being gathered at each. Though, as we’ve seen at, oftem times the rain gauges are clogged, missing, tilted, etc. Don’t recall seeing too many anemometers either.

  4. e.m.smith says:

    One of my favorite examples of your point is the desert in Canada that is just north of the Washington state border, a little inland. Say “desert” folks think Mojave, yet the same rainfall pattern (or lack of rainfall) happens roughly the same distance inland but way further north.

    Would folks think Canada had the same “desert climate” if all they looked at was the temperature? But the plants are clearly desert plants, as is the sand.

    Per the PS: See the “Posting ‘Rules'” tab.

  5. Jeff Alberts says:

    No problems on posting rules from me. I only do that on my own blog (which I don’t advertise, since it’s pretty offensive to just about everyone ;) )

  6. tty says:

    Have a look at this:

    Click to access upps_www.pdf

    That is the temperature record for Uppsala, Sweden 1722-2005, one of the longest and best temperature series in the world, courtesy of SMHI, the Swedish Weather Service (which is rather pro AGW). Notice that the 1720’s and 1730’s were warmer than the 1980’s and 1990’s, even though there may be some remaining UHI problems with the record, despite efforts to correct for it.

    Modern commentators always thinks Linnaeus was nuts, trying to grow mulberries and other southern crops around Uppsala back then. Maybe he wasn’t as crazy as they think.

  7. Rod Smith says:

    I always have to squirm when I hear that ‘Global Mean Temperature’ is used to predict anything.

    I remember Escape and Evasion training on the high desert of Nevada, I think in the month of February, many years ago. Making progress during the daytime meant stripping down to a tee shirt so as not to become too overheated.

    But when the sun went down it was a different story altogether. All the layers went back on, and my sweaty socks soon froze to the insoles of my shoes — which prompted me to build a fire to dry out and keep from losing toes — or more.

    ‘Mean’ temperature? What’s that?

  8. E.M.Smith says:

    @tty: That would explain why GIStemp tosses out data from prior to 1880. Nice cutoff at the bottom of the temperature trend…

    @Rod Smith: I would really like to see a comparison of the exact same trend / anomaly processes by using either min or max temps only. I think that would show a real trend, if any exists. Averaging them together hides more than it reveals…

    FWIW, in stock trading you use averages to hide the ‘noise’ you don’t want to see. It is used to make information go away, not to provide more. Any time I see the word “average” I always ask “What information is this step designed to hide? And is that A Good Thing, or Not?”

  9. M. Simon says:

    But the “average temp” as defined by weather stations is the daily high plus the daily low divided by two.

    Why? It is traditional from the time of glass thermometers.


    Or think about this: current models do time in 15 minute steps. How do you decide “initial conditions” for a computer run starting in 1880 when all you have is daily highs and lows from that era?

    And we know that the models are VERY sensitive to initial conditions.

    REPLY: [ Pre-electronics it was easy and cheap to make a “max” or “min” recording thermometer, but not a continuous recording thermometer. So getting the area under the daily temperature curve (to find the mean) was hard and expensive. (Min+Max)/2 was a simple expedient that was hoped to be close to the mean, maybe… Also, for things like crops and farming (major users of early temperature data) the min (i.e. frost) is critical to crop survival and the max is very important to things like fruit set and ripening. Farmers (among others) need min and max. Homeowners need to know min to protect against frozen pipes. The list goes on. Very few of the consumers of the data really care about the actual mean. -E.M.Smith ]

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