NationStates Jolt Archive

According to scientist interviewed in the June issue of Popular Science, earth's ice age is long overdue.
They report that while ice ages generally last a quarter of a million years, interglacial periods ( we are currently in an interglacial period) only last a few thousand years. This period has lasted over 12,000 years.
Scientists report that the next ice age could begin in 10 to 20 years and there is nothing humans can do to stop it except cross their fingers.
They are speculating that human emission of greenhouse gases may be what has delayed the next ice age but report that such emissions have been increasing so dramatically recently that they may actually cause the ice age that human induced emissions have up to this point been delaying. Hence, humans still need to reduce the use of fossil fuels but use them in limited quantities.
The climate change they are predicting is estimated to result in Western Europe and the eastern part of the US being turned into new siberias.
Resulting in global economic collapse, global famines, death and starvation, and warlordism worse than that seen currently in africa.
The political face of the planet will change along with the ecological face.
Many current nations will dissappear into the ash heaps of history. This includes Canada, Iceland, and the Scandanavian states and many parts of europe and possibly even the US of A could become part of the ash heap, breaking down into many feuding and warring nations.
Even Russia will collapse into many smaller warring nations.
But this phenomena will not be constrained to the first world. Many third world nations will experience economic collapse, famine, disease, death and destruction and will inevitably collapse into warring states.

Nice brave new world we are heading into, ain't it?

Pft. :rolleyes: People have been claiming the end of civilization is coming for centuries. I'll worry about it when I see it with my own two eyes.

According to scientist interviewed in the June issue of Popular Science, earth's ice age is long overdue.
They report that while ice ages generally last a quarter of a million years, interglacial periods ( we are currently in an interglacial period) only last a few thousand years. This period has lasted over 12,000 years.
Scientists report that the next ice age could begin in 10 to 20 years and there is nothing humans can do to stop it except cross their fingers.
They are speculating that human emission of greenhouse gases may be what has delayed the next ice age but report that such emissions have been increasing so dramatically recently that they may actually cause the ice age that human induced emissions have up to this point been delaying. Hence, humans still need to reduce the use of fossil fuels but use them in limited quantities.
The climate change they are predicting is estimated to result in Western Europe and the eastern part of the US being turned into new siberias.
Resulting in global economic collapse, global famines, death and starvation, and warlordism worse than that seen currently in africa.
The political face of the planet will change along with the ecological face.
Many current nations will dissappear into the ash heaps of history. This includes Canada, Iceland, and the Scandanavian states and many parts of europe and possibly even the US of A could become part of the ash heap, breaking down into many feuding and warring nations.
Even Russia will collapse into many smaller warring nations.
But this phenomena will not be constrained to the first world. Many third world nations will experience economic collapse, famine, disease, death and destruction and will inevitably collapse into warring states.

Nice brave new world we are heading into, ain't it?

Ah well, at least it will shake things up a bit. Maybe in the end things will turn out better. Or not...

Pft. :rolleyes: People have been claiming the end of civilization is coming for centuries. I'll worry about it when I see it with my own two eyes.
But the end of civ, will be like, so cool. And lots of fun. :)

Many third world nations will experience economic collapse, famine, disease, death and destruction and will inevitably collapse into warring states.
Isn't this already happening anyways?

(Begins looking to buy shotguns and assualt rifles and other survivalist stuff. Contemplates whether he needs to build a fortress.) ;)

Isn't this already happening anyways?
Sudan hardly constitutes the third world.

But the end of civ, will be like, so cool. And lots of fun. :)

*agrees*

Im looking forward the ice age...haven't seen any snow in ages

Scientists report that the next ice age could begin in 10 to 20 years and there is nothing humans can do to stop it except cross their fingers.

I thought we were at the beginning of the global climate period when the world is more warmer. Such a period is suppose to last for a few hundred year. Perhaps it is the reason why we are not having an ice age.

Maybe we should burn the Kyoto protocol to prevent the ice age; kill two birds with one stone.

Maybe we should burn the Kyoto protocol to prevent the ice age; kill two birds with one stone.
? :confused:

Sounds like a good idea to buy alot of guns and ammo. Maybe a bomb shelter fortress would be good to.

On geological timescales, yes, we are due an ice age. Plus or minus a few thousand years, it's due about now. I suggest we cross that bridge when we come nearer to it.

Whittier-, Sudan ain't the only 'third world' country suffering from these problems at the moment.

Liberia
Côte d'Ivoire
Guinea
Sierra Leone
Haiti
Tajikistan

I could go on but I'll spare you.

And this is why I hate enviromentalism.
"We're all screwed! We've always been screwed! Its overdue time for us to be screwed! However, we need to inconvenience ourselves anyway!"
Piffle, I say! Piffle and poppycock!
Its a new threat everyday, and they don't always make sense when lined up together.

"I read somewhere that the sun's getting hotter every year. It seems that pretty soon the earth is going to fall into the sun - or wait a minute - it's just the opposite - the sun's getting colder every year." Tom Buchanan; The Great Gatbsy by F. Scott Fitzgerald.

If we do find ourselves in the middle of a new ice age, we're not all doomed. Our ancestors 10,000 years ago managed to scrape themselves through, without any of the materials or technology which could be used today to further the survival of the human race.

If they survived, so can we. If the ice age happens, it happens. We'll have to deal with it just like our ancestors did, except that we'll be better equipped.

On geological timescales, yes, we are due an ice age. Plus or minus a few thousand years, it's due about now. I suggest we cross that bridge when we come nearer to it.

Whittier-, Sudan ain't the only 'third world' country suffering from these problems at the moment.

Liberia
Côte d'Ivoire
Guinea
Sierra Leone
Haiti
Tajikistan

I could go on but I'll spare you.

Most scientists agree that ice ages only take a decade to get a handle on the world.

Most?

Most scientists agree that ice ages only take a decade to get a handle on the world.
Maybe so. However, the next ice age could be thousands of years away given the margin for error I mentioned earlier.

Maybe so. However, the next ice age could be thousands of years away given the margin for error I mentioned earlier.
But you know that interglacial periods only last a few thousand years themselves.
This one has lasted for over 12,000 years.

Ok. Major periods of glaciation are rare events. There has only been 4 of them. They occur like every 200 million years (if you aren't a creationist).

In between periods of glaciation, there are multi-million year periods of more temperate climate, but within these temperate and severe periods occur. The colder periods are called 'glacial periods', the warmer periods 'interglacials'.

We are in an interglacial period now (the last retreat ending about 10,000 years ago). It's said interglacial periods last like 12,000 years or so.

According to my calculations... we have some 2000 years to stock up on guns.

goodbye scantily clad women. hello perpetual shrinkage. :(

A new Ice Age eh? SLED CITY!!! start movin to the mountains.

From this site, http://www.iceagenow.com/:

20 Aug 2004 - At least seven records for cold were shattered last night including in Winnipeg, where temperatures dropped to zero, breaking a record set in 1895. The cold also spread to Saskatchewan, with temperatures dipping to minus three degrees in Broadview. Winnipeg also saw snow pellets on Wednesday. Environment Canada has no previous record of snow falling in August.

Canadian summer temps coldest on record – August 22, 2004 - “It looks like it is going to be the coldest summer on record since data started being collected in the 19th century," says Rick Walls, a meteorologist at Environment Canada in Winnipeg.

In Saskatoon, temperatures on July 29 plunged to .07 degrees, the coldest since record keeping began in the area in 1892. Meanwhile, on July 23, temperatures in Winnipeg fell to three degrees, the lowest on record since 1872.

In the Canadian Prairies, temperatures for May through mid-August averaged three degrees below normal, beating records that go back to 1872, “completely eclips(ing) lows of 14.2 C which were recorded in 1883 and 1907.”


All time record cold in most of US.

Glaciers are growing around the world, including the United States (Mount Rainier, Mount St. Helens, and Mount Shasta, among others). See list of expanding glaciers.

List of growing glaciers:

NORWAY
Ålfotbreen Glacier
Briksdalsbreen Glacier
Nigardsbreen Glacier
Hardangerjøkulen Glacier
Hansebreen Glacier
Jostefonn Glacier
Engabreen glacier (The Engabreen glacier
is the second largest glacier in Norway. It is a
part (a glacial tongue) of the Svartisen glacier,
which has steadily increased in mass since the
1960s when heavier winter precipitation set in.)
Norway's glaciers growing at record pace. The face of the Briksdal glacier, an off-shoot of the largest glacier in Norway and mainland Europe, is growing by an average 7.2 inches (18 centimeters) per day.

* CANADA
Helm Glacier
Place Glacier

* ECUADOR
Antizana 15 Alpha Glacier

* SWITZERLAND
Silvretta Glacier

* KIRGHIZTAN
Abramov

* RUSSIA
Maali Glacier (This glacier is surging. See below)
Russia abandons Ice Station Vostok. Mar 4, 2003. For the first time ever, Russia is forced to abandon its base at Vostok. Due to heavier than usual pack ice, supply ships have been unable to reach their usual docking berths, leaving them unable to deliver fuel and supplies.

GREENLAND
Greenland glacier advancing 7.2 miles per year! The BBC recently ran a documentary, The Big Chill, saying that we could be on the verge of an ice age. Britain could be heading towards an Alaskan-type climate within a decade, say scientists, because the Gulf Stream is being gradually cut off. The Gulf Stream keeps temperatures unusually high for such a northerly latitude.

One of Greenland’s largest glaciers has already doubled its rate of advance, moving forward at the rate of 12 kilometers (7.2 miles) per year. To see a transcript of the documentary, go to http://www.bbc.co.uk/science/horizon/2003/bigchilltrans.shtml

The Greenland Ice Sheet is growing thicker.

# NEW ZEALAND
Photos show that all 48 glaciers in the Southern Alps have
grown during the past year. The growth is at the head of the
glaciers, high in the mountains, where they gained more ice
than they lost. Noticeable growth should be seen at the foot
of the Fox and Franz Josef glaciers within two to three
years.(27 May 2003)

# SOUTH AMERICA
- Moreno Glacier (the largest glacier in Patagonia)
- Pio XI Glacier (the largest glacier in the southern hemisphere)

UNITED STATES
New Glacier Forming on Mount St. Helens. During the last twenty years, snow and ice have accumulated behind the lava dome at Mount St. Helens (Washington State) to depths of up to 600 feet. According to Charles Anderson Jr. and Dr. Mark Vining of the Glaciospeleological Survey (IGS), the weight of the snow is compressing the lower layers into dense, crystalline glacier ice.
Glaciers growing on California's Mount Shasta! Oct 12, 2003. All seven of Mount Shasta's glaciers are growing, says Slawek Tulaczyk, a glaciologist at the University of California, Santa Cruz. This includes three-mile-long Whitney, the state's largest. Not only are the glaciers growing, three of them have doubled in size since 1950. Meanwhile, seven smaller glaciers in California's Sierra Nevadas are smaller than they were 100 years ago.

So is the Antarctic Ice Sheet. According to a report in Science (Jan 2002), new measurements show that the ice in parts of Antarctica is thickening. One week earlier, an article in Nature reported that Antarctica's harsh desert valleys - long considered a bellwether for global climate change - have grown noticeably cooler since the mid-1980s.

To put this in perspective, you must realize that the Antarctic Ice Sheet and Greenland Ice Sheets are almost twice as big as the contiguous United States. They're almost 100 times bigger than all of the rest of the world's glaciers put together. In other words, more than 99 percent of the world's glaciers are growing ... and all we hear about are the few that are melting.

Many people have asked why the glaciers in South America are melting. I think it is perfectly understandable. Remember, we have had two of the strongest El Ninos on record during the past 21 years. During an El Nino, a narrow band of the Pacific Ocean warms by as much as 14 degrees. This band of warm water travels east essentially along the equator until it slams into South America.

It seems logical that the increased rainfall caused by El Nino, plus the warmer winds blowing across the warmer water, could hasten glacial melt. But let me say it again. I do not believe that this is caused by humans, I think it is caused by the El Nino phenomenon, which is caused by underwater volcanism, which is increasing due to the ice-age cycle.
With this said, let me point out many glaciers in South America remain stable, and some - including the Pio XI Glacier and the Moreno Glacier - are growing. The Pio XI Glacier is the largest glacier in the southern hemisphere. The Moreno Glacier is the largest glacier in Patagonia.

Contrary to previous reports, Arctic ice did not thin during the 1990s, say researchers at the Department of Oceanography at Göteborg University in Göteborg, Sweden.

Geologists Unexpectedly Find 100 Glaciers in Colorado (This article appeared in the Hawaii Tribune Herald on 7 Oct 2001, by Joseph B. Verrengia. AP-NY-10-04-01)

Geologists exploring Colorado's Rocky Mountain Park say they discovered more than 100 additional glaciers here in a single summer, said Verrengia.

Officials previously believed the park, which is 60 miles northwest of Denver, included 20 permanent ice and snow features, including six named glaciers. The new survey, conducted by geologist Jonathan Achuff, shows there are as many as 120 features.

"Comparisons with historical photos suggest that at least some of the glaciers are expanding," say park officials. "Subtle climate changes may be helping the formation of glaciers or at least reducing their retreat."

"Glaciers are barometers of climate change," researchers said. "The survey results here contradict global warming trends. While precipitation hasn't changed much, temperatures have been slightly cooler in the past several years."

``We're not running quite in synch with global warming here,'' park spokeswoman Judy Visty said.

According to scientist interviewed in the June issue of Popular Science, earth's ice age is long overdue.
They report that while ice ages generally last a quarter of a million years, interglacial periods ( we are currently in an interglacial period) only last a few thousand years. This period has lasted over 12,000 years.
Scientists report that the next ice age could begin in 10 to 20 years and there is nothing humans can do to stop it except cross their fingers.
They are speculating that human emission of greenhouse gases may be what has delayed the next ice age but report that such emissions have been increasing so dramatically recently that they may actually cause the ice age that human induced emissions have up to this point been delaying. Hence, humans still need to reduce the use of fossil fuels but use them in limited quantities.
The climate change they are predicting is estimated to result in Western Europe and the eastern part of the US being turned into new siberias.
Resulting in global economic collapse, global famines, death and starvation, and warlordism worse than that seen currently in africa.
The political face of the planet will change along with the ecological face.
Many current nations will dissappear into the ash heaps of history. This includes Canada, Iceland, and the Scandanavian states and many parts of europe and possibly even the US of A could become part of the ash heap, breaking down into many feuding and warring nations.
Even Russia will collapse into many smaller warring nations.
But this phenomena will not be constrained to the first world. Many third world nations will experience economic collapse, famine, disease, death and destruction and will inevitably collapse into warring states.

Nice brave new world we are heading into, ain't it?

I CALL PRESIDENT

Antarctic glaciers surging. Masses of Antarctic ice have been moving twice as fast as usual, say researchers in a recent article in Science. Five of the six glacial tributaries that fed the Larsen Ice Shelf have entered "active surging phases." It is clear, they said, that the Boydell, Sjogren, Edgeworth, Bombardier and Drygalski glaciers are all surging. Mar 9, 2003. The Seattle Times.

Russian glaciers surging. On September 20, 2002, a huge 22-million ton piece of the gigantic Maili Glacier broke loose and crashed down a steep gorge into the village of Kami killing more than 150 people and injuring hundreds more.

The 500-foot wall of ice had been growing for six years. The Maili Glacier is just one of several glaciers in the North Caucasus Mountains that have been EXPANDING at an alarming rate. Other towns in the region have been partially buried by these advancing walls of ice. One local scientist in southern Russia said, "we may be seeing the beginning of a new great ice age!!!" (Thanks to climatologist Cliff Harris and meteorologist Randy Mann for this info.)

Greenland growing colder. Studies of historical meteorological data show that temperatures in this northern polar region have been falling. Over the last 40 or 50 years there has been "statistically significant cooling, particularly in south-western coastal Greenland. Sea-surface temperatures in the Labrador Sea also fell. The studies were made by Dr. Edward Hanna, from the University of Plymouth, UK, and Dr. John Cappelen, of the Danish Meteorological Institute, and presented in the Journal of Geophysical Review Letters. BBC News. 11

Alaska's Hubbard Glacier surging. Yakutat, Alaska. July 15, 2002. Bulldozing a gravel moraine in front of it, the Hubbard Glacier is advancing so rapidly that has nearly cut off Russell Fiord from Disenchantment Bay. The resulting ice and gravel dam is cutting off the supply of salt water, turning Russell Fiord into Russell Lake, endangering the small fishing village of Yakutat.

Russell "Lake" is now rising at the rate of six inches a day as freshwater from snowmelt and rainfall continues pouring in. Once the lake level rises to about 130 feet, it will begin spilling over into the nearby Situk River basin, flooding the usually tranquil stream. This would all but destroy the world-class salmon and steelhead fishing in the area, and devastate Yakutat's economy.

The Hubbard Glacier, 73 miles long and 6 miles wide at the face, is the largest tidewater glacier in North America.

The Nisqually Glacier on Washington's Mt. Rainier is growing thicker at the rate of more than 18 feet per year. With all of the added weight, scientists expect the glacier to begin advancing within this decade (Washington Geology, p. 24, Sep 2000).

Why is the glacier growing? I visited the Nisqually Glacier in August of 2002. A sign at the Park Ranger's desk said that average snowfall in the area is 650 inches per year. However, during the July 1, 2001 to Jun 30, 2002 season, snowfall measured 836 inches. This is a 26 percent increase. That's why the glacier is growing; above-average precipitation.

And where is the precipitation coming from? From seas being warmed by above-average underwater volcanic activity.
Or it could be that human greenhouse emissions are warming the seas too much.
(italics mine)

Glaciers in Montana's Glacier Park on the verge of growing.
5 Oct 2002. The Going-to-the-Sun road through Glacier Park opened on one of the latest dates since the road was built, on 28 June, says Darrell Christofferson, who lives near the park. The reason for the late opening was a blizzard on the 12th of June, said Christofferson. Up to four feet of snow fell in the vicinity of Logan Pass and halted plowing of the road.

In addition, snow fell early on Logan Pass this fall, said Christofferson. Three to four inches of snow fell on the pass during the last week of September, forcing closure of the road for a few days. This year's Sun road "season" has been the shortest ever.

To exacerbate matters, cold weather has arrived in the area earlier than usual. It will be interesting to see how much snow from last season remains when they plow next spring.

I think this is yet one more signal that we're on the verge of an ice age.

Satellites show overall increases in Antarctic Sea Ice Cover Around Antarctica. Claire Parkinson of NASA's Goddard Space Flight Center found that sea ice seasons have lengthened by at least one day per year over an area of 2.16 million square miles (about 3/4 of the size of the continental United States). This is roughly twice as large as the area where sea ice seasons have shortened by at least one day per year.

Sea ice now covers the area for three weeks longer per year than it did 21 years ago. Annals of Glaciology, Aug 22, 2002

Melting glacier 'false alarm.' Aug 22, 2002. News Telegraph. Pictures claiming to show how man-made global warming has caused Arctic glaciers to retreat are at best misleading, says leading glaciologist.

The pictures, which compared the size of a glacier on Svalbard in 1918 with its size in 2002, included the warning that global warming caused by man-made greenhouse gases was causing Arctic glaciers to melt.

Those assertions are misleading at best, says Professor Ole Humlum, a leading Norwegian glaciologist. "That glacier had already disappeared in the early 1920s," says Humlum. "[It disappeared] as a result of a perfectly natural rise in temperature that had nothing to do with man-made global warming."

Extreme cold over South Pole reveals global warming models are wrong. Auckland (AFP) Sep 10, 2002. A discovery that it is much colder over the South Pole than believed has exposed a major flaw in the computer models used to predict global warming.

Scientists based at the Amundsen-Scott South Pole Station have found that it is 36 to 54 degrees Fahrenheit (20 to 30 degrees C) colder than computer models showed.

The findings, by Chester Gardner, a professor of electrical and computer engineering at the University of Illinois, Weilin Pan, a doctoral student at Illinois, and Ray Roble of the US National Center for Atmospheric Research, published their findings in the American Geophysical Union Letters.

Construction crane suddenly buried beneath antartic ice:
http://www.iceagenow.com/Growing_Antarctic_Ice_Sheet.htm
It took only 40 years.

Interesting post Whittier, truly. I'm no expert on these issues, but hasn't it been said that pollution and the green house effect will first cause the overall cloud cover around the globe to grow... which first leads to a cooler period, followed by all around warming because the radiation can't be mirrored back...(or summink like that).

Interesting post Whittier, truly. I'm no expert on these issues, but hasn't it been said that pollution and the green house effect will first cause the overall cloud cover around the globe to grow... which first leads to a cooler period, followed by all around warming because the radiation can't be mirrored back...(or summink like that).
That's new to me.
Greenhouse gases don't normally just congregate into clouds. The last global cloud was caused by a meteor impact accompanied by a surge a global volcanism.
If they do, I would think they would have formed a global cloud cover by now, as long as we've been putting out such gases.
But an interesting idea nonetheless.

Published on Friday, January 30, 2004 by CommonDreams.org
How Global Warming May Cause the Next Ice Age...
by Thom Hartmann


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.

Not the Gases themselves they heat up the world a bit then more water evaporates and causes more clouds I think I also am not an expert

That's new to me.
Greenhouse gases don't normally just congregate into clouds. The last global cloud was caused by a meteor impact accompanied by a surge a global volcanism.
If they do, I would think they would have formed a global cloud cover by now, as long as we've been putting out such gases.
But an interesting idea nonetheless.

Oh, poorly worded on my part. What I meant the warming causes clouding... meh, never mind.

Ohh yeah I remeber hearing about the gulf stream stoping as part of gobal climate change.

Another source with good climatology models:

http://www.whoi.edu/institutes/occi/currenttopics/abruptclimate_joyce_keigwin.html