The day after tomorrow

[ElPelado]

I saw the movie last day and I have a question: is it possible that only one hemisphere enters teh Ice Age???


At least in the movie USA had us(the 3rd world)...

[Evil Dr Ganymede]

Don't you know that the Southern Hemisphere doesn't exist in disaster movies? (hell, you're lucky if the rest of the world even gets a mention... in Deep Impact all we heard of Europe and Africa was "millions died there too" in the speech at the end )

But to answer the question... If past ice ages are anything to go by then I think both poles should theoretically ice up, yes. But since most of the high latitudes in the southern hemisphere are water-covered and the high latitudes in the northern hemisphere are land, that means that in the south - apart from Antarctica - there's less ground to anchor the ice on. I suspect the ice sheets therefore wouldn't be so extensive in the southern hemisphere - it would be struggling to reach the tip of South America, and Australia is probably too far north to be covered by ice.

[ElPelado]

They didnt talk about the south, but the three storms that caused the glaciation appear only in the north. They show many maps and satellite images(some of them taken by astronauts in the ISS) that show that only the northern emisphere is cold and show nothing but small clouds in teh south...

btw: I really liked the image near the end when the astronauts said that they have never seen the earth so clear(without clouds) and they show Italy completely white...

[eburacum45]

This movie is wrong in many respects; it is possible that the reversal of the Atlantic circulation would cause local cooling in Europe and North America, but nothing like that depicted;
global warming is most likely to lead to a rise in overall global temperatures with some small areas of localised cooling.

in fact I believe there is some doubt that global warming would affect the Atlantic conveyer at all.

[Evil Dr Ganymede]

I finally saw the film today (fun!). I figured that Italy wouldn't be visible from space as the familiar "boot" under the ice though, I thought the ice would extend over the mediterranean.

Conveniently enough, the film didn't show the high southern latitudes at all (though it mentioned that Australia had been hit by the biggest typhoon in its history). I didn't spot any huge copy/pasted superstorms brewing in the southern hemisphere on the screen with the simulation either .

Maybe they got away with it .

[Hummin]

I hate that kind of movies, they make mi sick.

[granthutchison]

I hate that kind of movies, they make mi sick.

Personally, I thought it was a lot of climate shift.

Grant

[Pliskin]

i forgot how they explained it but is it truly possible for the winds of the storm to get that cold as to deep freeze anything it came in contact with? Thats pretty close to absolute zero...

[ACrisp]

The movie got many things wrong, but the possibility of global warming causing an ice age is very much a real one.

When the last ice age drew to a close some eleven thousand years ago, the melting glaciers in North America created a large freshwater lake in Central Canada (Lake Aggiziz [sic?] ) This freshwater lake eventually drained into the Atlantic ocean by way of the Saint Lawrence seaway, dumping enough freshwater into the ocean to dilute it. This was enough to change the "Great Conveyor" or "Atlantic Conveyor" deep sea current, so that cold water stayed near the north pole, and warm water stayed near the tropics. The result was that the glaciers resurged, and over a few centuries, buried Northern Europe in ice.

Today, human accellerated global warming is gradually melting the icecaps, adding freshwater into the ocean, at a rate that may or may not be similar to the draining of Lake Aggiziz. If the ice is melting "fast" enough, it would add enough freshwater to disrupt the current again, and a small (between 500 and 1000 years) ice age would reign in Europe, North America, and probably chunks of Asia once again.

The big divergence between reality and the movie is, of course, the time it takes for this ice age to get going. In reality, we probably have between a few decades and a century before the glaciers get enough "steam" in their expansion to pose a threat to civilization, and even then, their expansion would be measured in kilometers per year, not per minute. In fact, during the "Little Ice Age" that lasted between 1560 and 1850, glacier surges were fast enough to terrify onlookers: The Mer de Glace on Mount Blanc was so frightening in its expansion that it was exorcised three times - once by the Bishop of Paris - to supposedly halt its spread!

Of course, a century-long buildup is too long for a movie, so Hollywood, being Hollywood, decided to ignore reality. They took the root cause, and exaggerated it so much, that if people were to raise the subject of global warming causing an ice age in serious discussion, they would not be taken seriously - not, that is, until food shortages and gradually dropping temperatures turn Canada and Europe into most undesireable areas of real-estate...

As for the flashfreezing that did in the Maritime Provinces (where I happen to live) and New England... nope, not possible. For it to get THAT cold THAT fast, you'd need several things to happen more or less all at once:

- The Sun would need to go out,
- The Earth's greenhouse layer would have to vanish instantly. In fact, we'd probably need to strip the entire planet's atmosphere away, which causes some more immediate concerns than freezing ,
- The Earth - ALL of the Earth - would have to get an aldebo of 1 (perfect reflector),
- And, the Earth's core would probably have to lose all or nearly all heat.

I think we're safe from becoming humansicles.

[maxim]

The Mer de Glace on Mount Blanc was so frightening in its expansion that it was exorcised three times

I never heard of a glacier beeing exorcised That's droll

maxim

[eburacum45]

In this article Wallace Broecker, the guy who originated the idea of Atlantic Conveyer Reversal says he doubts that the film reflects reality in an accurate way.

http://www.newscientist.com/news/news.jsp?id=ns99994888

In particular, I believe the cooling that happened at the end of the last ice age started from a scenario with much more ice in the northern hemisphere anyway. Climate change at the beginning and end of an ice age is very rapid and subject to fluctuations.

we are in fact headed into entirely new territory with anthropogenic global warming, but I do not believe that we are on the verge of making our planet uninhabitable.

Far worse than localised cooling will be the economic impact of a relatively small sea level rise, which will impact hundreds of millions of people and trillions of dollars of real estate.