Posted on 11/04/2011 4:02:52 PM PDT by decimon
A new study at the University of Arizona's Laboratory of Tree-Ring Research has revealed a previously unknown multi-decade drought period in the second century A.D.
Almost nine hundred years ago, in the mid-12th century, the southwestern U.S. was in the middle of a multi-decade megadrought. It was the most recent extended period of severe drought known for this region. But it was not the first.
The second century A.D. saw an extended dry period of more than 100 years characterized by a multi-decade drought lasting nearly 50 years, says a new study from scientists at the University of Arizona.
UA geoscientists Cody Routson, Connie Woodhouse and Jonathan Overpeck conducted a study of the southern San Juan Mountains in south-central Colorado. The region serves as a primary drainage site for the Rio Grande and San Juan rivers.
"These mountains are very important for both the San Juan River and the Rio Grande River," said Routson, a doctoral candidate in the environmental studies laboratory of the UA's department of geosciences and the primary author of the study, which is upcoming in Geophysical Research Letters.
The San Juan River is a tributary for the Colorado River, meaning any climate changes that affect the San Juan drainage also likely would affect the Colorado River and its watershed. Said Routson: "We wanted to develop as long a record as possible for that region."
Dendrochronology is a precise science of using annual growth rings of trees to understand climate in the past. Because trees add a normally clearly defined growth ring around their trunk each year, counting the rings backwards from a tree's bark allows scientists to determine not only the age of the tree, but which years were good for growth and which years were more difficult.
(Excerpt) Read more at eurekalert.org ...
Extra dry ping.
global warming no doubt.
those toyotas, priuses, buicks, ... destroy the environment.
Aztec SUVs are the cause.
Oh Knows, Global Warming from us today affected the Roman Empire 2000 years ago... It went through a time warp or something...:)
No worries. ☺
Ain’t no century got MORE THAN A HUNERT YEARS!
Ah ,the Romans , it was those open toe sandals and all that concrete
Huh?
True enuff!
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GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach | |
Thanks decimon. |
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Huh?
They are using the interstitial dendritic chronological catalysm of neuronic development that defines the difference between critical thinking and being criticized for your thinking...
Isn’t that about the Anasazi left their pueblos?
Previous megadroughts in America: 2nd Century +/-; 12th Century +/-.
21st Century Time Magazine cover:
IS AMERICA HEADED INTO A MEGADROUGHT CRISIS?
Ten things YOU can do NOW to prepare!
Related stories:
President Appoints Water Czar pg 13
The Health Benefits of Dust Baths pg 37
How To Choose & Install a Flushless Toilet pg 42
You May Not Get Blood From a Turnip, But They DO Contain Precious Water pg 52
Learning From Our Pets: How to Use Your Tongue for Personal Grooming pg 69
These are the same guys that claim they can tell the temperature long years ago from tree ring widths. Now they say they can tell how much rainfall there was too. Which is it?
These guys are a regular tree ring circus.
The Bush/Rove weather machine is an amazing thing isn’t it?
both
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