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RobBob

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  1. (If the Conveyor currents stop, won't we be in for an ice age, rather than a warming trend? ) (had to print the article from a subsrip journal) December 18, 2003 -Arlington, Va. -- Tropical ocean waters have become dramatically saltier over the past 40 years, while oceans closer to Earth's poles have become fresher, scientists report in the December 18th issue of the journal Nature. These large-scale, relatively rapid oceanic changes suggest that recent climate changes, including global warming, may be altering the fundamental planetary system that regulates evaporation and precipitation and cycles fresh water around the globe. The study was conducted by Ruth Curry of the Woods Hole Oceanographic Institution (WHOI); Bob Dickson of the Centre for Environment, Fisheries, and Aquaculture Science in Lowestoft, U.K.; and Igor Yashayaev of the Bedford Institute of Oceanography in Dartmouth, Canada. 'This study is important because it provides direct evidence that the global water cycle is intensifying,' said Elise Ralph, associate director of the National Science Foundation's (NSF) physical oceanography program, which funded the research. 'This is consistent with global warming hypotheses that suggest ocean evaporation will increase as Earth's temperature does. These issues are particularly important as pressure on freshwater resources has become critical in many areas around the world.' An acceleration of Earth's global water cycle can potentially affect global precipitation patterns that govern the distribution, severity and frequency of droughts, floods and storms. It would also exacerbate global warming by rapidly adding more water vapor-itself a potent, heat- trapping greenhouse gas-to the atmosphere. And it could continue to freshen North Atlantic Ocean waters to a point that could disrupt ocean circulation and trigger further climate changes. The oceans and atmosphere continually exchange fresh water. Evaporation over warm, tropical and subtropical oceans transfers water vapor to the atmosphere, which transports it toward both poles. At higher latitudes, that water vapor precipitates as rain or snow and ultimately returns to the oceans, which complete the cycle by circulating fresh water back toward the equator. The process maintains a balanced distribution of water around our planet. The oceans contain 96 percent of the Earth's water, experience 86 percent of planetary evaporation, and receive 78 percent of planetary precipitation, and thus represent a key element of the global water cycle for study, the scientists said. Because evaporation concentrates salt in the surface ocean, increasing evaporation rates cause detectable spikes in surface ocean salinity levels. In contrast, salinity decreases generally reflect the addition of fresh water to the ocean through precipitation and runoff from the continents. Curry, Dickson, and Yashayaev analyzed a wealth of salinity measurements collected over recent decades along a key region in the Atlantic Ocean, from the tip of Greenland to the tip of South America. Their analysis showed the properties of Atlantic water masses have been changing-in some cases radically-over the five decades for which reliable and systematic records of ocean measurements are available, the scientists report. They observed that surface waters in tropical and subtropical Atlantic Ocean regions became markedly saltier. Simultaneously, much of the water column in the high latitudes of the North and South Atlantic became fresher. This trend appears to have accelerated since 1990-when 10 of the warmest years since records began in 1861 have occurred. The scientists estimated that net evaporation rates over the tropical Atlantic have increased by five percent to ten percent over the past four decades. These results indicate that fresh water has been lost from the low latitudes and added at high latitudes, at a pace exceeding the ocean circulation's ability to compensate, say the scientists. Taken together with other recent studies revealing parallel salinity changes in the Mediterranean, Pacific, and Indian Oceans, a growing body of evidence suggests that the global hydrologic cycle has revved up in recent decades. Among other possible climate impacts, an accelerated evaporation - precipitation cycle would continue to freshen northern North Atlantic waters. The North Atlantic is one of the few places on Earth where surface waters become dense enough to sink to the abyss. The plunge of this great mass of cold, salty water helps drive a global ocean circulation system, often called the Ocean Conveyor. This Conveyor helps draw warm Gulf Stream waters northward in the Atlantic, pumping heat into the northern regions that significantly moderates wintertime air temperatures, especially in Europe. If the North Atlantic becomes too fresh, its waters would stop sinking and the Conveyor could slow down. Analyses of ice cores, deep-sea sediment cores, and other geologic evidence have clearly demonstrated the Conveyor has abruptly slowed down or halted many times in Earth's history. That has caused the North Atlantic region to cool significantly and brought long-term drought conditions to other areas of the Northern Hemisphere over time spans as short as years to decades. Melting glaciers and Arctic sea ice, another consequence of global warming, are other sources of additional fresh water to the North Atlantic. An accelerated water cycle also appears to be increasing precipitation in higher latitudes, contributing to the freshening of North Atlantic waters and increasing the possibility of slowing the Conveyor. A cooling of the North Atlantic region would slow the melting process, curtail the influx of fresh water to the North Atlantic. The Conveyor would again begin to circulate ocean waters. But global warming and an accelerated water cycle would continue to bring fresh water to high latitudes-possibly enough to maintain a cap on the Conveyor even if the Arctic melting ceased. Monitoring Earth's hydrological cycle is critical, the scientists said, because of its potential near-term impacts on Earth's climate.
  2. RobBob

    global dimming

    I don't buy it. Meanwhile, supposedly the cattle in Patagonia are getting more sunburn and glaucoma than ever.
  3. RobBob

    Stupid is...

    Somebody's gotta be at the bottom of the barrel.
  4. RobBob

    I ruined it

    (as I tried to post, before we ground to a halt) Xylenes, bad shit for your head. Don't huff 'em.
  5. Trask has brought so many viruses to this board from his streaming porn feeds. And they hang like barnacles and weeds off the hull of this ship of fools, slowing our forward progress to a crawl...
  6. Here's a fine, fine MILF:
  7. NOW we're talkin' real women. Hilaree but Lokelani's hot too. Woo Hoo---what a way to start the day! IMHO, her cover shot was even better.
  8. RobBob

    Saddam Makeover

  9. hmmm...I never really reflected on it. But now that trask mentions it, as a kid I spent a lot of time at a hunt club where several local judges hunted. I've seen judges take & eat illegal species, heard them joke about sampling drug evidence, observed them shitfaced, etc. I think trask has a point.
  10. Funny, I read the geoduck thing in a trade paper. In two different cases recently, two guys will do time for illegally importing undersized spiny lobsters. The Feds come down very hard in illegal seafood busts. I'm glad you ended up with Nicole Brodeur (touchy-feely liberal that she is)...she used to write for the Raleigh paper. I discovered she was in Seattle, seeing an article she wrote about climbing on Baker with Ed Viesturs. (I figured with her last name that her hubby played hockey for the Hurricanes in NC.)
  11. RobBob

    I ruined it

    Using piss to clean up a shit streak?
  12. Last-minute move to revert to the Clinton plan of 1/2 the number of snowmobiles this winter...0 next winter. Snowmobiles, jetskis, all whiny 2-stroke engines:
  13. Today at 10:35EST marks 100 years since the Wright bros got their first few seconds of powered flight. (Warren Buffet once said "they should have shot Orville down.") There is quite a celebration taking place over on Kill Devil Hills, about 75 miles as the crow flies from my home. There will be a reenactment if the weather cooperates, which it appears it will (20-25mph winds; a balmy 62 degrees). Bush will speak there this morning. Hell, even Google is getting in on the act. Actually, thinking about the amazing changes in human life during the past 100 years has me reluctantly becoming a greenie. After all, quite a large percentage of the messes that we have created for ourselves on Earth's crust have happened in just that time period. Think about the divergent paths that humanity could take in this next 100 years, and what a huge difference it would make in the way the world looks by then. I still come back to population control as the best means of environmental control. There are 4 times as many people on Earth now as there were 100 years ago! Maybe the next SARS or the like will curb what we as a world community do not have the gumption to even discuss: controlling/reducing world population. My ramble for the day.
  14. RobBob

    Jim McDermott

    nuts!
  15. RobBob

    Jim McDermott

    I think it's an FF look...he's thinking "delivered a good rogering; job well done!"
  16. Good example of why it doesn't work/last...two very dangerous parts of the world.
  17. RobBob

    Jim McDermott

    and you have a consistent problem with masculinity, it appears.
  18. Poor diction, but well-said nonetheless
  19. RobBob

    hello fukkas

    How come when I hit Who's Online, everybody is either shown as Ignoring trask or Ignoring Marylou ?
  20. Oh, last week your mom got $100 for the 'modeling job' from the Canadian Public Service Film Institute for her fine performance.
  21. R-rated...may not be cube safe... Health Canada message
  22. what IS with this quickreply? test
  23. RobBob

    Wow!

    does "Hmmmmmm!" count?
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