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Pink Spider
01-31-2004, 01:51 AM
How Global Warming May Cause the Next Ice Age

by Thom Hartmann

http://www.commondreams.org/views04/0130-11.htm

While global warming is being officially ignored by the political arm of the Bush administration, and Al Gore's recent conference on the topic during one of the coldest days of recent years provided joke fodder for conservative talk show hosts, the citizens of Europe and the Pentagon are taking a new look at the greatest danger such climate change could produce for the northern hemisphere - a sudden shift into a new ice age. What they're finding is not at all comforting.

In quick summary, if enough cold, fresh water coming from the melting polar ice caps and the melting glaciers of Greenland flows into the northern Atlantic, it will shut down the Gulf Stream, which keeps Europe and northeastern North America warm. The worst-case scenario would be a full-blown return of the last ice age - in a period as short as 2 to 3 years from its onset - and the mid-case scenario would be a period like the "little ice age" of a few centuries ago that disrupted worldwide weather patterns leading to extremely harsh winters, droughts, worldwide desertification, crop failures, and wars around the world.

Here's how it works.

If you look at a globe, you'll see that the latitude of much of Europe and Scandinavia is the same as that of Alaska and permafrost-locked parts of northern Canada and central Siberia. Yet Europe has a climate more similar to that of the United States than northern Canada or Siberia. Why?

It turns out that our warmth is the result of ocean currents that bring warm surface water up from the equator into northern regions that would otherwise be so cold that even in summer they'd be covered with ice. The current of greatest concern is often referred to as "The Great Conveyor Belt," which includes what we call the Gulf Stream.

The Great Conveyor Belt, while shaped by the Coriolis effect of the Earth's rotation, is mostly driven by the greater force created by differences in water temperatures and salinity. The North Atlantic Ocean is saltier and colder than the Pacific, the result of it being so much smaller and locked into place by the Northern and Southern American Hemispheres on the west and Europe and Africa on the east.

As a result, the warm water of the Great Conveyor Belt evaporates out of the North Atlantic leaving behind saltier waters, and the cold continental winds off the northern parts of North America cool the waters. Salty, cool waters settle to the bottom of the sea, most at a point a few hundred kilometers south of the southern tip of Greenland, producing a whirlpool of falling water that's 5 to 10 miles across. While the whirlpool rarely breaks the surface, during certain times of year it does produce an indentation and current in the ocean that can tilt ships and be seen from space (and may be what we see on the maps of ancient mariners).

This falling column of cold, salt-laden water pours itself to the bottom of the Atlantic, where it forms an undersea river forty times larger than all the rivers on land combined, flowing south down to and around the southern tip of Africa, where it finally reaches the Pacific. Amazingly, the water is so deep and so dense (because of its cold and salinity) that it often doesn't surface in the Pacific for as much as a thousand years after it first sank in the North Atlantic off the coast of Greenland.

The out-flowing undersea river of cold, salty water makes the level of the Atlantic slightly lower than that of the Pacific, drawing in a strong surface current of warm, fresher water from the Pacific to replace the outflow of the undersea river. This warmer, fresher water slides up through the South Atlantic, loops around North America where it's known as the Gulf Stream, and ends up off the coast of Europe. By the time it arrives near Greenland, it's cooled off and evaporated enough water to become cold and salty and sink to the ocean floor, providing a continuous feed for that deep-sea river flowing to the Pacific.

These two flows - warm, fresher water in from the Pacific, which then grows salty and cools and sinks to form an exiting deep sea river - are known as the Great Conveyor Belt.

Amazingly, the Great Conveyor Belt is only thing between comfortable summers and a permanent ice age for Europe and the eastern coast of North America.

Much of this science was unknown as recently as twenty years ago. Then an international group of scientists went to Greenland and used newly developed drilling and sensing equipment to drill into some of the world's most ancient accessible glaciers. Their instruments were so sensitive that when they analyzed the ice core samples they brought up, they were able to look at individual years of snow. The results were shocking.

Prior to the last decades, it was thought that the periods between glaciations and warmer times in North America, Europe, and North Asia were gradual. We knew from the fossil record that the Great Ice Age period began a few million years ago, and during those years there were times where for hundreds or thousands of years North America, Europe, and Siberia were covered with thick sheets of ice year-round. In between these icy times, there were periods when the glaciers thawed, bare land was exposed, forests grew, and land animals (including early humans) moved into these northern regions.

Most scientists figured the transition time from icy to warm was gradual, lasting dozens to hundreds of years, and nobody was sure exactly what had caused it. (Variations in solar radiation were suspected, as were volcanic activity, along with early theories about the Great Conveyor Belt, which, until recently, was a poorly understood phenomenon.)

Looking at the ice cores, however, scientists were shocked to discover that the transitions from ice age-like weather to contemporary-type weather usually took only two or three years. Something was flipping the weather of the planet back and forth with a rapidity that was startling.

It turns out that the ice age versus temperate weather patterns weren't part of a smooth and linear process, like a dimmer slider for an overhead light bulb. They are part of a delicately balanced teeter-totter, which can exist in one state or the other, but transits through the middle stage almost overnight. They more resemble a light switch, which is off as you gradually and slowly lift it, until it hits a mid-point threshold or "breakover point" where suddenly the state is flipped from off to on and the light comes on.

It appears that small (less that .1 percent) variations in solar energy happen in roughly 1500-year cycles. This cycle, for example, is what brought us the "Little Ice Age" that started around the year 1400 and dramatically cooled North America and Europe (we're now in the warming phase, recovering from that). When the ice in the Arctic Ocean is frozen solid and locked up, and the glaciers on Greenland are relatively stable, this variation warms and cools the Earth in a very small way, but doesn't affect the operation of the Great Conveyor Belt that brings moderating warm water into the North Atlantic.

In millennia past, however, before the Arctic totally froze and locked up, and before some critical threshold amount of fresh water was locked up in the Greenland and other glaciers, these 1500-year variations in solar energy didn't just slightly warm up or cool down the weather for the landmasses bracketing the North Atlantic. They flipped on and off periods of total glaciation and periods of temperate weather.

And these changes came suddenly.

For early humans living in Europe 30,000 years ago - when the cave paintings in France were produced - the weather would be pretty much like it is today for well over a thousand years, giving people a chance to build culture to the point where they could produce art and reach across large territories.

And then a particularly hard winter would hit.

The spring would come late, and summer would never seem to really arrive, with the winter snows appearing as early as September. The next winter would be brutally cold, and the next spring didn't happen at all, with above-freezing temperatures only being reached for a few days during August and the snow never completely melting. After that, the summer never returned: for 1500 years the snow simply accumulated and accumulated, deeper and deeper, as the continent came to be covered with glaciers and humans either fled or died out. (Neanderthals, who dominated Europe until the end of these cycles, appear to have been better adapted to cold weather than Homo sapiens.)

What brought on this sudden "disappearance of summer" period was that the warm-water currents of the Great Conveyor Belt had shut down. Once the Gulf Stream was no longer flowing, it only took a year or three for the last of the residual heat held in the North Atlantic Ocean to dissipate into the air over Europe, and then there was no more warmth to moderate the northern latitudes. When the summer stopped in the north, the rains stopped around the equator: At the same time Europe was plunged into an Ice Age, the Middle East and Africa were ravaged by drought and wind-driven firestorms. .

If the Great Conveyor Belt, which includes the Gulf Stream, were to stop flowing today, the result would be sudden and dramatic. Winter would set in for the eastern half of North America and all of Europe and Siberia, and never go away. Within three years, those regions would become uninhabitable and nearly two billion humans would starve, freeze to death, or have to relocate. Civilization as we know it probably couldn't withstand the impact of such a crushing blow.

And, incredibly, the Great Conveyor Belt has hesitated a few times in the past decade. As William H. Calvin points out in one of the best books available on this topic ("A Brain For All Seasons: human evolution & abrupt climate change"): ".the abrupt cooling in the last warm period shows that a flip can occur in situations much like the present one. What could possibly halt the salt-conveyor belt that brings tropical heat so much farther north and limits the formation of ice sheets? Oceanographers are busy studying present-day failures of annual flushing, which give some perspective on the catastrophic failures of the past. "In the Labrador Sea, flushing failed during the 1970s, was strong again by 1990, and is now declining. In the Greenland Sea over the 1980s salt sinking declined by 80 percent. Obviously, local failures can occur without catastrophe - it's a question of how often and how widespread the failures are - but the present state of decline is not very reassuring."

Most scientists involved in research on this topic agree that the culprit is global warming, melting the icebergs on Greenland and the Arctic icepack and thus flushing cold, fresh water down into the Greenland Sea from the north. When a critical threshold is reached, the climate will suddenly switch to an ice age that could last minimally 700 or so years, and maximally over 100,000 years.

And when might that threshold be reached? Nobody knows - the action of the Great Conveyor Belt in defining ice ages was discovered only in the last decade. Preliminary computer models and scientists willing to speculate suggest the switch could flip as early as next year, or it may be generations from now. It may be wobbling right now, producing the extremes of weather we've seen in the past few years.

What's almost certain is that if nothing is done about global warming, it will happen sooner rather than later.

Ally_Kat
01-31-2004, 02:23 AM
I'm not one of these people who's worried about everything. You got people like this around you? Country's full of them now. People walking around ALL day long, every minute of the day, worried about EVERYTHING. Worried about the air, worried about the water, worried about the soil. Worried about insecticides, pesticides, food additives, carcinogens. Worried about rayon gas, worried about saving endangered species.

Let me tell you about endangers species, alright? Saving endangered species is just one more arrogant attempt by humans to control nature. It's arrogant meddling. It's what got us in trouble in the first place. Doesn't anybody understand that? Interfering with nature. Over 90% - over, way over 90% - of all the species that have EVER lived on this planet, ever lived, are gone. They're extinct. We didn't kill them all. They just...disappeared. That's what nature does. They disappear these days at a rate of 25 a day. And I mean regardless of our behavior. Irrespective of how we act on this planet, 25 species that were here today will be gone tomorrow. Let them go gracefully. Leave nature alone. Haven't we done enough? We're so self-important. SO self-important.

And everybody is going to save something:
save the trees
save the bees
save the whales
save those snails.

And the greatest arrogance of all - save the planet.

What? Are these fucking people kidding me? Save the planet? We don't even know how to take care of ourselves yet. We haven't learn how care for one another - we're going to save the fucking planet? I'm getting tired of that shit. I'm tired of fucking Earth Day. I'm tired of these self-righteous environmentalists; these white bourgeois liberals who think the only thing wrong with this planet is that there aren't enough bicycle pads. People trying to make the world safe for their Volvos. Besides, environmentalists don't give a shit about the planet. They don't care about the planet. Not in the abstract they don't. You know what they're interested in? A clean place to live. Their own habitat. They are worried that sometime in the future they personally might be inconvenienced. Narrow, unenlightened self-interest doesn't impress me.

Besides, there is nothing wrong with the planet. The planet is fine. The PEOPLE are fucked. Difference. Difference. The planet is fine. Compared to the people, the planet is doing great; Been here 4 and a half billion years. Didja ever thing about the arithmetic? Planet's been here 4 and a half billion years. We've been here, what, a 100,000. Maybe 200,000? And we've only been engaged in heavy industry for little over 200 years. 200 years verses over 4 and a half billion. And we have the conceit to think that somehow we're a threat? That somehow we're going to put in jeopardy this little blue-green ball that's just afloatin' around the sun? The planet had been through a lot worse than us. Been through all kinds of things WORSE than us. Been through earthquakes, volcanoes, plate tectonics, continental drift, solar flares, sunspots, magnetic storms, the magnetic reversal of the poles...hundreds of years of bombardment by comets and asteroids and meteors, worldwide floods, tidal waves, worldwide fires, erosion, cosmic rays, reoccurring ice ages, and we think some plastic bags and some aluminum cans are going to make a difference? The planet isn't going anywhere. We are. We're going away. Pack your shit, folks, we're going away. And we wont' leave much of a trance, either, thank God for that. Maybe a little styrofoam, maybe, a little styrofoam. The planets will be here, but we'll be long gone. Just another failed mutation. Just another closed end biological mistake. An evolutionary cul-de-sac. The planet will shake us off like a bad case of fleas - a surface nuisance. You want to know how the planet's doing? Ask those people in Pompeii, who are frozen in position from volcanic ash, how the planet's doing. Want to know if the planet's alright? Ask those people in Mexico City, or Armenia, or a hundred other places, buried under thousands of tons of rock and earthquake rubble if they feel like a threat to the planet this week. How about those people in Kilauea who build their homes right next to an active volcano and then wonder why they have lava in the living room.

The planet will be here for a long, long, loooong time after we're gone, and it will heal itself, and it will cleanse itself, 'cuz that's what it does. It's a self-correcting system. the air and the water will recover, the earth will be renewed, and if it's true that plastic is not degradable, well, the planet will simply incorporate plastic into a new paradigm - the Earth plus plastic. The Earth doesn’t share our prejudice towards plastic. Plastic came out of the Earth. The Earth probably sees plastic as another one of its children. Could be the only reason the Earth allowed us to be spawned from it in the first place; It wanted plastic for itself. Didn't know how to make it; Needed us. Could be the answer to our age-old philosophical question, why are we here? PLASTIC, assholes.

So, the plastic is here. Our job is done. We can be phased out now and I think that's been started already, don't you? I mean, to be fair, the planet probably sees us as a mild threat. Something to be delta with and I'm sure the planet will defend itself in the manner of a large organism, like a beehive or an ant colony can muster a defense, I'm sure the planet will think of something. What would you do if you were the planet trying to defend against this pesky troublesome species?

Let's see...what might...hmmm...viruses. Viruses might be good. They seem vulnerable to viruses. And viruses are tricky because they're always mutating and forming new strains whenever a vaccine is created. Perhaps this first virus can be one that compromises the immune system of these creatures. Perhaps the Human Immunodeficiency Virus making them vulnerable to all other diseases and infections that might come along. And maybe it could be spread sexually, making them a little reluctant to engage in the act of reproduction.

Well, that's a poetic note, and it's a start; And I can dream, can't I?

~George Carlin.

Wayne L.
01-31-2004, 10:01 AM
Global warming is " nothing more " than just a figment of the imagination of " extreme enviromentalist groups " on the left like Save The Earth & their hardcore followers like former VP Al Gore who have " too much time " on their hands concerned about the environment since " mother nature " can take care of itself without them anyway.

John Ashcroft
01-31-2004, 10:29 AM
Notice how the commies are re-evaluating the global warming spin ever since Algore made a fool of himself when preaching alarmist global warming stories on the coldest day on record...

So now it's "Global warming is causing the next ice age!"

Cathedral
01-31-2004, 11:15 AM
Well, hot water does freeze quicker than cold water, lol.

Don't believe me? Take the initiative and test the theory...

Take two ice trays, fill one with hot water and the other with cold water, set them in the freezer and the hot water will crystalize first, it's true...

John Ashcroft
01-31-2004, 01:45 PM
No doubt, but I hardly think the analogy works here... And damn it dude, don't give the clowns any ideas! The next thing we'll be seeing on CNN is fucking ice cube tray "experiments". They'll probably be administered by Begala and Carville.

Ally_Kat
01-31-2004, 04:36 PM
Originally posted by Cathedral
Well, hot water does freeze quicker than cold water, lol.

Don't believe me? Take the initiative and test the theory...

Take two ice trays, fill one with hot water and the other with cold water, set them in the freezer and the hot water will crystalize first, it's true...

I have to try that now only cuz I'm a dork with stuff like that :o

Ally_Kat
01-31-2004, 04:41 PM
Originally posted by John Ashcroft
No doubt, but I hardly think the analogy works here... And damn it dude, don't give the clowns any ideas! The next thing we'll be seeing on CNN is fucking ice cube tray "experiments". They'll probably be administered by Begala and Carville.

Can we have him as the guest speaker?

please oh please oh please oh please?! http://cmw.dailymoviereviews.com/contrib/fk/hearts.gif

Cathedral
01-31-2004, 05:02 PM
Originally posted by John Ashcroft
No doubt, but I hardly think the analogy works here... And damn it dude, don't give the clowns any ideas! The next thing we'll be seeing on CNN is fucking ice cube tray "experiments". They'll probably be administered by Begala and Carville.

LMMFAO, sorry bro, i don't know what i was thinking.. :p

The fact is, this earth was once a great big snowball as the dispersment of fossil and rock discoveries has proven time and time again.
And it will return to that state eventually, if we don't incinerate ourselves first and leave the planet dead for years and years to come.

It is just a cycle of nature that is being accelerated by our pollution. But the rate of accceleration isn't fast enough to make all that much difference since the earth being a living organism has the ability to heal itself.
If we reduce emmissions by just 2%, and we have globally, the rate of ozone deterioration slows by almost 10% bi-annually...

Bottom line is this, The earth will destroy us hundreds of years, maybe thousands of years before we destroy it.
Again, barring we don't start playing tennis with nuclear bombs...

Cathedral
01-31-2004, 05:05 PM
At one time, the DNA for humanity was entombed in Ice. we are stupid fucks to think we have any control over what this globe does and when it does it.

John Ashcroft
01-31-2004, 09:35 PM
That pretty much sums up the Conservative position on this issue.

Oh, and BTW, before any of you libs get on your high horse... I recycle. I recycle more than most Americans will ever. I do it because I'm disgusted with the sight of our landfills (and I think the recycle market will be profitable soon). I do it because you can melt plastic to make more plastic. Although I wonder if the libs realize it takes the burning of fossil fuels to accomplish this wonderful feat...

I also find it shocking that the liberal crowd is pushing lead acid batteries (or any battery) as the answer for propulsion in the 21st century. Talk about pollution! Now instead of having minute quantities of pollutants in the air, we'll have hard core pollutants soaking into middle America's water supply! Good plan idiots! When are you going to realize that you don't get something for nothing??? (I know you Commies will have a hard time with this concept.) You simply can't get free energy. There is always going to be a trade off. If you enviro-whackos were sincere (in other words, not simply anti-capitalist), you'd be embracing nuclear energy with passion. Perhaps you just want all of us to go back to the cave dwelling days?... (So long as you don't have to give up your television, right?)

Cathedral
01-31-2004, 10:07 PM
Way to lower the smack to the liberal lips, JA...

I would love to buy this solar home that just went on the market up the road.
The house is in the ground and there is a yard on the roof, lol.
It's got these huge ass solar panels sticking out of the ground and it is a pretty big house.

pricetag: $178,000.00
That's about $78,000.00 beyond my price range, but it is a sharp fucking house.

Pink Spider
01-31-2004, 10:40 PM
Originally posted by John Ashcroft
Oh, and BTW, before any of you libs get on your high horse... I recycle. I recycle more than most Americans will ever. I do it because I'm disgusted with the sight of our landfills (and I think the recycle market will be profitable soon). I do it because you can melt plastic to make more plastic. Although I wonder if the libs realize it takes the burning of fossil fuels to accomplish this wonderful feat...

It takes less fossil fuels than from starting from scratch. I think that's the whole point, to bring it down.

I also find it shocking that the liberal crowd is pushing lead acid batteries (or any battery) as the answer for propulsion in the 21st century. Talk about pollution! Now instead of having minute quantities of pollutants in the air, we'll have hard core pollutants soaking into middle America's water supply! Good plan idiots!

It would be more helpful if you bothered to explain what the hell you're talking about and providing a source. But, no of course that never happens.

When are you going to realize that you don't get something for nothing??? (I know you Commies will have a hard time with this concept.) You simply can't get free energy. There is always going to be a trade off. If you enviro-whackos were sincere (in other words, not simply anti-capitalist), you'd be embracing nuclear energy with passion.

Environmentalists are not anti-capitalists. If a corporation pollutes your drinking water and you develop certain diseases from it would that make you anti-capitalist from complaining about it? Would you do nothing like a good little corporate socialist?

Corporations should be held accountable for their actions. If they were free to do whatever they wanted, we all pay the price, because the majority are into the bottom line, not safety of the people that have to live next door to them.

Why are you so much against corporations being held accountable for their actions? Safety costs so little in the long run and sometimes may even bring up productivity. Look at some of the capitalists in Japan, they're actually smart enough to figure out that keeping the worker healthy and happy makes them more productive. If you kill off all of your potential consumers, what are you going to do then?

And if you believe that the brightest scientists in the world would came up with global warming as some kind of anti-capitalist conspiracy, then you're the ones probably wearing the tin-foil hats.
You and your kind sound about as ridiculous as flat-earthers and 7 day creationists.

Perhaps you just want all of us to go back to the cave dwelling days?... (So long as you don't have to give up your television, right?)

So, are the Amish closer to a liberal or conservative viewpoint?

Cathedral
02-01-2004, 12:08 AM
Conservative, I know a few Amish people and they don't play the immorality game.
Amish folks are closer to being Jesus like than any Corporate Church you'll find in America.

If they could throw fire and brimstone at us so called "normal" americans they damn sure would be, daily.

They are against more than your average Conservative Republican which makes them pretty much hardcore republicans by definition.

The problem is, they don't vote...

Satan
02-01-2004, 01:03 PM
Jesus dressed better than the Amish. He kept his wardrobe simple - a robe, some sandals, and that diaper thingy that you see Him wearing in all the Crucifixion pictures, but JC made it work. Hey, He's the Son of the Big Guy, of course He's gonna have a sense of style, right?

Not as cool as my classic red suit, of course, but what is?? :cool:

Anyway, if you mortals want to avoid any chance of an ice age, there's only one place where you are truly safe from that possibility :D

Cathedral
02-01-2004, 01:49 PM
but only until the end, dude. Your days are numbered and you know it, lol.