Friday, May 2, 2008

Pacific Decadal Shift

As of May Day, NASA has announced that due to a "Pacific Decadal Shift " (PDS), the years 2010 - 2029 will likely represent a global cooling phase. Of course, this looming PDS is but one climatological factor out of many, nor does NASA provide context or perspective on any related non-PDS episodes. But this scenario accords well with alternating warming/cooling phases of increasing frequency from 1890, the end of a 500-year Little Ice Age from the late-middle 14th Century (about AD 1350).

Over fifty years, 1890 - 1939, Earth experienced an extreme warming rebound. From 1940 - 1979, forty years, patterns turned noticeably cold (remember Newsweek's notorious glacial alarmism?). Then over thirty years, 1980 - 2009 has devolved a relatively milder stage, though satellite data indicates not warming but a stable climate regime from 1996/98. So NASA's 20-year extrapolation (2010 - 2029) precisely fits a 120-year old pattern.

Alas, cycles of ever-higher frequencies, greater amplitudes must end when global thermostats crash by simultaneously switching on and off. After an inchoate period of conflicting, rapid shifts through (say) 2069 (thirty years from 2029), quite possibly our Holocene Interglacial will become one with Nineveh and Tyre as Ice Time proceeds on cyclical schedule for 110,000 years. We're overdue by 1,500 years already.

Global climate is "chaotic" in Lorenz's fractal-geometric sense (non-random, but strictly indeterminate). Nature, objective reality, cares nothing for skewed computer models, which by mathematical necessity are useless anyhow. But cycles are cycles, whatever elements or factors they entail. We've warned the kids, as this 21st Century wears on, to seek out lower latitudes. By 2029 if not before, the weight of "cooling" evidence will be undeniable.

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