Walker Circulation

Not by Fire but by Ice



  6 May 2006      


Weakening wind pattern could trigger El Niņo 
and an ice age


4 May 06 - An important wind circulation pattern over the Pacific Ocean has weakened significantly during the past century, say scientists.

Although few people have heard of the vast loop of winds known as the Walker Circulation, its effects are felt worldwide - as disruptive El Niņo episodes, seasonal Asian monsoons and the upwelling of cold water from the deep ocean that nourishes marine food chains.

The Walker circulation pattern traces a huge loop that spans almost half the circumference of the Earth. Trade winds blow across the Pacific from east to west. The air rises in the western Pacific, then returns eastward a few miles up. Then it sinks back to the surface and starts the loop again.

Variations in the intensity and structure of the Walker Circulation affect climate across the planet, said Gabriel Vecchi of the University Corporation for Atmospheric Research in Princeton, New Jersey. "The scale of this feature is enormous."

In the current issue of Nature, Vecchi and colleagues report that the Walker Circulation pattern, source of the trade winds in the tropical Pacific, has weakened by 3.5 percent since the mid-1800s. Most of the weakening has occurred in the past 50 years.

"This rate at which the Walker Circulation is weakening appears to be accelerating," Vecchi says."We don't know what it's going to do, but the scale of this feature is so enormous that it is basic to the structure of the atmosphere."

A temporary weakening of the Walker Circulation is one of the key events signaling the onset of an El Niņo, which brings devastating droughts to Southeast Asia, Indonesia and Australia, violent winter storms to the U.S. West Coast, and a sharp decline in fishing along the Pacific coast of South America.

Researchers say any long-term weakening might lead to more frequent, or perhaps even chronic, El Niņo-like disruptions across the Pacific basin.


          Did you catch that? "Violent winter storms to the 
          U.S. West Coast."

          The article blames the wind-pattern shift on "human-induced 
           climate change," which I think is rubbish. The Walker Circulation
           pattern - and El Niņos - have been around for millions of years, 
           long before humans set foot on this planet. Oh, and notice that
           they’re calling it "climate change," not "global warming."

          I think this slow-down in the Walker circulation pattern more 
          likely indicates that we’re headed into an ice age. Studies show 
          that during past ice ages the Pacific Ocean behaved much as it 
          does today in an El Niņo - or super El Niņo - event. 
(See Ice Ages Looked Like El Niņo)

          That’s what I see happening now.

          While the Gulf Stream and Atlantic Conveyor shut down brings 
          on the ice in Europe, Canada, and the Northeast United States, 
          a Walker Circulation shutdown could bring on the ice on the 
          Western Canadian and US coasts.

          Perhaps this is why Korea, Japan, Russia, China, India, etc.,
          had record-breaking cold, ice, and snow this last year?






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