My question is spurred by a recent National Geographic article on Alaska. And it outlined how the glaciers affect the surrounding mountain terrains and how the massive fjords were carved out during the last Ice Age. That article coupled with the crazy winter we have been having globally - Jerusalem has a foot of snow today - my question is simple…
How would modern civilization cope with another Ice Age?
What measures would be taken on a national scale?
Just who would be affected? Could we ski in Iraq? Wonder about Tanzanian ski vacations? Would the former Sovet Union be one large glacier?
Modern civilization probably couldn’t cope with it. There’d be mass migrations south, away from the ice. Current northern centers of commerce (i.e., Toronto, Moscow, Oslo, e.g.) would be innundated with ice, while some only slightly farther south (New York, London, Warsaw, etc.), would be nearly uninhabitable. Those countries around the equator, formerly too hot to become population centers, would see their weather become more temperate. So the balance of power and business would shift to those countries.
Unfortunately, the old northern countries would not be willing to take this lying down, so tension and agression would rise. Nuclear war breaks out when Russia,the US, and other cold members of the atomic club decide they want some warm real estate. The resulting fallout causes a nuclear winter, and the entire globe becomes encased in ice.
I realize the book is largelt tongue-in-cheek, but it seems to suggest that this problem wouldn’t have come up if we’d just kept on producing greenhouse gases.
London is about 8 degrees further north than Toronto. New York is roughly on the same latitude as Madrid, Rome and Istanbul. (I’m estimating from a time-zone map in a pocket diary here!). Surprised me, I must admit.
I think an inherent problem would be that we would know and recognize the problem, and see the changes taking place. Global temperatures would shift and Phoenix would start getting seasons. We would see it coming over hundreds of years. As a matter of fact isn’t there a website that shows when the next ice age will be in full force?
A Creed for the Third Millennium by Colleen McCullogh imagines a United States confronted with a new ice age, where the population is rapidly abandoning the northern states and overwhelming the southern ones.
Well, during all the Ice Ages we had previously, the ice only came down as far as the middle of Illinois, latitude-wise. If you’re going to postulate “ice caps down to Texas”, you’re talking Science Fiction, I think, not Science.
And according to what I learned in school, the climate in Illinois during the Ice Ages was “High Arctic tundra”, with things like foxes living literally in the shadow of the glaciers, so if foxes could survive an Illinois Ice Age, I would suppose that people could handle it, too, without needing to flee for their lives to the Gulf Coast. " :rolleyes: "
People would just live in the shadow of the glaciers, too, that’s all, but I don’t see much else changing. Snow blowers would definitely be a growth industry. Fedders would be bankrupt.
Remember that it would just be “colder” and “snowier” in the winters than normal, but the day length would be the same. We’d still have four seasons in Illinois, only they’d be “high Arctic” kinds of seasons. The days would get shorter, the days would get longer, just the way they do now, there would still be a “High Arctic” kind of summer, but “snow” would start sooner and last longer. That would be the only difference.
Except that they’d probably start teaching kids how to put on snow chains in Drivers Ed, instead of expecting their granddad to show them right in the middle of the Blizzard of the Century.
And I bet they’d be legal in all states except Hawaii.
People live nowadays in tremendously cold and snowy climates (Minnesota, Norway, Siberia) and life goes on. I don’t see anybody in Norway fleeing for their lives to the south. People have an advantage over foxes in that they can invent things like space heaters and snowblowers to help them survive the cold.
Anyone know what the first changes would be? Would it just be longer winters? Or would we have longer winters on a much grander scale? Personally I love snow. But I do have my threshold.
How fast do the glaciers advance and temperatures and sea levels drop in a serious ice age? Would we notice the differences within generations, or only within hundreds or thousands of years?
Another side-effect: changing sea levels may alter ocean currents and circ. patterns, resulting in, say, the elimination of the gulf stream that currently keeps England from turning into a fudgsicle.
I forgot about changing seal levels! Port cities would become inland cities, which would have a drastic effect on economies (imagine NYC, LA, Miami, Houston, London, etc. without ports).
Dropping the average mean temperature 10 to 20 degrees would probably trigger mass extinctions. The drier weather would have a major effect on rain forests (which are already threatened by mankind).
I guess I’m taking the very negative view of life in an ice age because there is two feet of frozen snow out on my lawn right now…
You’re forgetting the most immediate and drastic change.
We wouldn’t be able to grow food.
They haven’t yet come up with a crop that can grow in the tundra, so as the tundra climate moves toward the tropics, the amount of land available to grow food will shrink. It will shrink even more as people crowd into the relatively narrow temperate zone.
The Canadian Prairies, the U.S. Great Plains, the Ukraine and other vast food-producing regions will lose the ability to grow corn, wheat, etc. Calfornia’s valleys, one of the richest agriculutral areas in the world, will clog with people.
Perhaps there’ll be more rainfall over the Sahara, the Arabian Desert, the Southwest U.S., etc., and those areas will become more hospitable to growing crops. But until that happens, mass changes in eating habits (less meat, more grains) and unfortunately, mass food shortages, will make life very uncomfortable.
Glaciers form when snow falls in the winter, but never melts in the summer. Repeat for a few dozen years and you’ve got a glacier. Nothing magical about it, continental glaciers don’t “move” south, or “retreat” north. Snow falls and either melts or doesn’t melt.
Also remember that humans could definately affect global climate if it was felt that something had to be done. If you spray black carbon dust over a glacier during the summer, it is going to melt. We can pump greenhouse gasses into the atmosphere, or some other tricks. Basically every thing that people tell us not to do for global warming, we do on purpose.
The thing is, we wouldn’t just kick into a glacial period without knowing it. Like I said, the glaciers don’t just come roaring down from Canada, they form in place. Some disruption to the global climate would have to happen, like the collapse of the gulf stream, resulting in a new global climactic equilibrium. We’d notice if the gulf stream shut down.
Actually, there is pretty good evidence that continent-sized ice sheets existed at a latitude of about 10 degrees (think modern-day Costa Rica) at least once in Earth history, and very likely on two other occasions as well. However, since these events occurred more than 550 million years ago under rather different circumstances than currently exist on the Earth’s surface, I don’t think we need to worry about it happening again.
As lesa pointed out, we are still in the middle of an ice age, one that began 1.8 million years ago. We are just living in an interglacial interval, defined by somewhat milder climatic conditions compared to a full bore glaciation. Since we still have ice caps in Greenland and Antarctica, we can’t say that we are living in a true greenhouse world. Shifting back into full bore glacial conditions - meaning ice sheets on the other continents - would start with an overall cooling of global climate, of course, producing all sorts of impacts on human civilization as well as the environment. There is some evidence to suggest that dramatic temperature changes can occur over just a decade or two. If that were to happen, the chief struggles would have to do with food and fuel supplies. Agricultural zones would indeed shift southward, and the overall climate would be drier… so, for example, Canada’s ability to produce crops would be significantly diminished. Demand for heating fuel would also go up considerably, and I suspect oil prices would go through the roof (and maybe some serious research into alternative fuels would finally roll forward ).
Re-growth of the ice sheets themselves (like the Laurentide ice sheet in North America at the Last Glacial Maximum, 21,000 BP; look here for an illustration) would take thousands of years, so we would have plenty of time to get out of the way. But since Phlosphr wants to cut right to the chase:
You would indeed see mass migration of people to more southerly latitudes. Yes, there are people who live right now in places where winters are pretty inhospitable. HOWEVER… I really doubt there would be too many takers for living on top of an ice sheet (the South Pole is a good example. Ice sheets have altitude - about 3 to 4 km in their centers - and you would have to import EVERYTHING except water (food, fuel, other consumables, etc.). There is just no benefit to living long-term in that sort of environment.
Along the fronts of the ice sheets… yes, this would be a tundra-like setting, potentially habitable, but not by many. Again, resources for living here would be in somewhat short supply, even for a population density that was fairly low. Bear in mind, too, that the ice sheets will change weather patterns owing to their height… and they produce katabatic winds, density-driven air currents that would bring cold air down off the glacier. Brrr…
I think it is unavoidable that people would get squeezed into a much smaller living space. As Guy Propski mentioned, the growth of the ice sheets would produce a corresponding drop in sea level, so places where continental shelves are present (east coast of the US, Southeast Asia/Indonesia/northern Australia) would gain some territory (and some coastal cities could be as much as 100 miles away from the new shoreline). Also on the plus side, the Sahara Desert would likely become a friendly and habitable place again. However, I believe that human civilization is going to be in for a rough ride unless there is a heretofore unheard-of level of cooperation between governments. Equatorial countries would be absorbing large number of people while their own populations are still growing, and all these folks have to fit so that crops could still be grown… (On preview, I see that kunilou has made that point well.) I unfortunately can envision plenty of conflicts over such things.
Also… continental glaciers do actually move - they will eventually flow under their own weight, once they’re thick enough, but that takes a lot more than a few dozen years to grow an ice sheet - a few thousand is much more likely. The scoured landscape of much of Canada is testament to the grinding power of ice sheets. And incidentally, the Gulf Stream is more likely to shut down at the end of a glacial interval, when fresh meltwater enters the ocean in sufficient quantity to disrupt thermohaline circulation in the North Atlantic.
