Medieval Warm Period seen in western USA tree ring fire scars

Medieval Warm Period seen in western USA tree ring fire scars“. Anthony Watts darkly hints that “despite what some would like you to believe, the MWP was not a regional ‘non event’.” Then he copy-and-pastes a University of Arizona news release about how Giant Sequoias reveal fire histories in the Sierra Nevada. (I’ll try to ignore his reflexive figure comparing the global “Mann/IPCC” temperature history to the European “historical” temperature history.)

This is not a climate paper, it’s about historical fire frequencies and even implicitly recognizes the progression of global warming. You can read Multi-Millennial Fire History of the Giant Forest, Sequoia National Park, California, USA (Swetnam, et. al, 2009) at the Fire Ecology journal web site (abstract or PDF). Anthony didn’t.

Can someone point out the Medieval Warm Period?

1 thought on “Medieval Warm Period seen in western USA tree ring fire scars

  1. Giant Sequoias Yield Longest Fire History from Tree Rings

    The paper itself is available without a paywall.

    The Medieval Period discussion consists of:

    “The giant sequoia fire history indicates that fire frequently increased during the Medieval Period (about 800C.E. to 1300C.E.), and that major drought events, and to a lesser degree warming trends, probably contributed to this increase. A broad range of paleoclimatic, lake level, and fire history reconstructions confirm that the Medieval Period was exceptionally dry in the western US…This has generally been identified as the “Medieval Warm Period,” but global extent comparisons of paleoclimatic data indicate that it was not a uniformly warm period around the planet…In general…the western United States, and specifically the Sierra Nevada, was clearly in a period of exceptional and extended drought about the late 800’s C.E. to about 1300 C.E…
    “Giant sequoia fire histories show the effects of this aridity with maximum fire frequencies recorded over the past two millenia. The overall driest two periods in the western North American region in the Cook etal(1999) network were centered on the mid 1100s C.E. and mid 1200s C.E., which correspond very well with decadal maxima in fire frequency in the giant sequoia groves…”

    This location, if its warm enough, would still be a somewhat redundant listing in skeptic-site’s informal list of global Medieval Warm sites. There are six or seven other listings in the various categories, that cover nearby areas.

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