Posted on 01/24/2007 7:50:30 AM PST by jcb1379
In one of the most stark illustrations of how a changing climate can have regional effects, scientists have learned that winds over North America have done a complete 180 since the time of the last Ice Age several thousand years ago. Winter blizzards and spring thunderstorms today are usually fueled by moisture-laden winds blowing in from the West Coast. “In this study, we found evidence that during the last glacial period, about 14,000 to 36,000 years ago, the prevailing wind in this zone was easterly, and marine moisture came predominantly from the East Coast,” said lead study author Xiahong Feng of Dartmouth College.” The findings were detailed today in the online edition of the journal Geology. Changing climate These changes in wind direction were the result of global climate change, which can alter circulation patterns in the atmosphere, Feng explained. Changes in wind patterns can in turn cause changes in temperature and precipitation patterns, which are the measurements typically used to study past climates. “Climate change involves interactions among temperature, precipitation and wind, but until now, research has rarely been able to observe or confirm prehistoric winds and their continental-scale patterns,” Feng said. The researchers examined cellulose from ancient wood samples recovered from the mid-latitudes of North America (40-50 degrees N). The changes in the compositions of oxygen and hydrogen isotopes across the continent gave the researchers a picture of the distribution of moisture during the glacial period. While modern samples show high levels of moisture on both coasts, the ancient samples surprisingly showed high levels on the East Coast that steadily decreased to the West Coast. “We didn’t expect to see a whole different pattern,” co-author Eric Posmentier told LiveScience.
(Excerpt) Read more at livescience.com ...
WIND PATTERNS changed with the last climate change. How hard is it to notice a cyclical nature to this thing? Idiots see the levels of CO2 rise in the last 100 years and the temperature rise, thus, correlation = causation.
I read once that you can take every single person on the planet and they could live in Texas. That is how few people there are on the planet and how little affect they have.
Serious Climate Change: Winds Blew in Reverse During Last Ice Age
What else; Bush's Fault!
In one of the most stark illustrations of how a changing climate can have regional effects, scientists have learned that winds over North America have done a complete 180 since the time of the last Ice Age several thousand years ago.
Winter blizzards and spring thunderstorms today are usually fueled by moisture-laden winds blowing in from the West Coast.
“In this study, we found evidence that during the last glacial period, about 14,000 to 36,000 years ago, the prevailing wind in this zone was easterly, and marine moisture came predominantly from the East Coast,” said lead study author Xiahong Feng of Dartmouth College.”
The findings were detailed today in the online edition of the journal Geology.
Changing climate
These changes in wind direction were the result of global climate change, which can alter circulation patterns in the atmosphere, Feng explained. Changes in wind patterns can in turn cause changes in temperature and precipitation patterns, which are the measurements typically used to study past climates.
“Climate change involves interactions among temperature, precipitation and wind, but until now, research has rarely been able to observe or confirm prehistoric winds and their continental-scale patterns,” Feng said.
The researchers examined cellulose from ancient wood samples recovered from the mid-latitudes of North America (40-50 degrees N). The changes in the compositions of oxygen and hydrogen isotopes across the continent gave the researchers a picture of the distribution of moisture during the glacial period. While modern samples show high levels of moisture on both coasts, the ancient samples surprisingly showed high levels on the East Coast that steadily decreased to the West Coast.
“We didn’t expect to see a whole different pattern,” co-author Eric Posmentier told LiveScience.
Altered jet stream
Feng hypothesizes that the Laurentide Ice Sheet, which covered a large area of North America during the Ice Age, intensified winds swirling around the North Pole. This intensification caused the jet stream, along which many storms tend to track, to dip further south than does today and the weak polar easterlies above it were pushed down over the mid-latitudes of North America.
Essentially, the wind patterns of today “got squished down toward the equator,” Posmentier said.
These changes in wind direction in turn changed precipitation patterns. For example, the Pacific Northwest was found to be much drier than it is today, which earlier studies of vegetation in that region have also shown.
Feng hopes that the methods her team used in this study can be used to better understand climate interactions and to formulate better models of future climate change.
I think there is still a lot of hot air blowing across the country from the East coast.
I find this hard to believe. The Coriolis effect has the most influence on global wind patterns and no one has suggested that the Earth was rotating in the opposite direction... yet. However, given all of the junk science out there presently I would not be surprised to hear that this will result from climate "change" too.
I am dumbfounded. My understanding is that the general weather patter of west-to-east is a result of coriolis force driven by the earth's rotation.
You mean, like, the East Wind blew out of the West and the North Wind blew out of the South??
Whoa! What have we done to this planet???
I don't think this is settled fact yet. Writers always tend to write their stories as though every scientific discovery is a set in stone law. Science is open to examination and debate.
Let's not tell Algore. At least not until after the Oscars.
Given the Gore Effect, that is precisely the moment when the winds will again change direction and we will officially be in another Ice Age. /s
Damn those prehistoric SUV'S!!!!
They would fit in Texas and each would have 1100 square feet of space to themselves.
What nonsense!
Everybody knows that the world was founded 6,000 years ago by the word of God.
I wonder how high the skyscapers would have to be to accomplish that?
The earth didn't flip on its axis, but the magnetic field has.
"The earth didn't flip on its axis, but the magnetic field has."
The magnetic field has and appears to be about to again. Pretty good consensus on that.
Flipping on its axis is a good more unlikely. A rotating earth acts like a giant gyro. It wants to keep moving in the same direction. A flip would force it out of that movement. Seems unlikely. Yet the theories are out there. I suspect that they exist to explain the changes in magnetic field that may also be explained by the magnetic field reversals. I'm agnostic on axis flip.
The way I heard it put was, essentially, every person on earth, man, woman, and child, would get a trailer house and enough land to put it on, and all could fit in Texas. So much for the "footprint" we are leaving...
Remember reading in the 1970's about a professor at a midwestern university that got a government grant to study the effect of 18 wheelers passing on Interstates causing tornadoes and if driving on the left side of the road would alleviate the problem.
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