Some Common Sense on Treemometers

I have written a lot about historic temperature proxies based on tree rings, but it all boils down to “trees make poor thermometers.”  There are just too many things, other than temperature, that can affect annual tree growth.  Anthony Watts has a brief article from one of his commenter that discusses some of these issues in a real-life way.  This in particular struck me as a strong dose of common sense:

The bristlecone records seemed a lousy proxy, because at the altitude where they grow it is below freezing nearly every night, and daytime temperatures are only above freezing for something like 10% of the year. They live on the borderline of existence, for trees, because trees go dormant when water freezes. (As soon as it drops below freezing the sap stops dripping into the sugar maple buckets.) Therefore the bristlecone pines were dormant 90% of all days and 99% of all nights, in a sense failing to collect temperature data all that time, yet they were supposedly a very important proxy for the entire planet. To that I just muttered “bunkum.”

He has more on Briffa’s increasingly famous single hockey stick tree.

  • Fred from Canuckistan . . .

    So how many hockey sticks can the IPCC make from a single tree ?

  • Landin

    Climate-alarmist scientists blatantly disregard historical and archaeological evidence of the Medieval Warm Period and Little Ice Age while using a dozen trees in Siberia to produce the hockey stick graph. Politicians then try to guilt the planet into vast taxation and control of natural resources. Meanwhile the castrated media plays along with the alarmists and politicians and prints story after story about scary “climate change.” Sounds like fiction, but it’s the truth.

  • Sawed

    For 10 years, Briffa behaved like a petulant little boy with something to hide. Now that the cat is out of the bag, the only whining excuse the hockey team can come up with is “Steve Mc hurt my feewings!!!” Pathetic.

    Too much money is riding on the climate catastrophe steamroller to allow mere science to slow it down. Boys, you can forget about any of this influencing the policymakers at the top. They’ve made up their minds that everything is settled.

  • AnonyMoose

    So basically the bristlecone pines are only collecting data on the warmest temperatures. They only record rising temperatures and ignore any cooling.

    If you have bristlecone pines at different altitudes of the same mountain, you might be able to compare the differences to find changes in conditions. But “conditions” includes changes in more than temperature. And I’m not aware of inter-tree analysis being done.

  • kuhnkat

    Hey, it is all just a big misunderstanding!!!

    From Briffa’s statement about SteveM’s work:

    “Whether the McIntyre version is any more robust a representation of regional tree growth in Yamal than my original, remains to be established.”

    See, it is only about tree growth rates. Nothing to do with temperature proxies!!!

    HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA