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The Coming Mega-Drought: It's already happened!
Reference
Stahle, D.W., Cook, E.R., Cleaveland, M.K, Therrell, M.D., Meko, D.M., Grissino-Mayer, H.D., Watson, E. and Luckman, B.H.  2000.  Tree-ring data document 16th century megadrought over North America.  EOS, Transactions, American Geophysical Union 81: 121, 125.

What was done
The authors developed a long-term history of drought over North America from reconstructions of the Palmer Drought Severity Index (PDSI) based on analyses of many lengthy tree-ring records.

What was learned
It was found that the 1930s Dust Bowl drought in the United States - which was the nation's most severe, sustained, and wide-spread drought of the past 300 years - was eclipsed in all three of these categories by a 16th century "megadrought."  This drought persisted "from the 1540s to 1580s in Mexico, from the 1550s to 1590s over the Southwest, and from the 1570s to 1600s over Wyoming and Montana" and "extended across most of the continental United States during the 1560s."  It also recurred with greater intensity over the Southeast during the 1580s to 1590s.  So horrendous was this climatic event, that the authors unequivocally state that "the 'megadrought' of the 16th century far exceeded any drought of the 20th century."  In fact, they state that "precipitation reconstruction for western New Mexico suggests that the 16th century drought was the most extreme prolonged drought in the past 2000 years."

What it means
Think of what would happen if such a drought were to commence today, or if a drought of mere Dust Bowl-intensity were to occur.  Look at what is already happening with the garden-variety drought that might occur in the single year of 2000 and you have your answer.  Anyone skeptical of CO2-induced global warming would be crucified; for in the able hands of those who are hell-bent on convincing the people of the world, and the people of the United States in particular, of the reality of CO2-induced global warming, this phenomenon would, for all practical purposes, be proof-positive they are right.  Yet, they would still be wrong; but they would win anyway.  The suffering at the hands of nature would be so great that no amount of logic or evidence to the contrary would stand in the way of their achieving their goal.

So what does it mean?  We better pray for rain.


Reviewed 1 July 2000