A New Ice Age-A.D. 1000

[chunkeymonkey13q]

How would the various empires and states present throughout the world at the time of A.D. 1000 be affected, if one or several of the major currents which distribute heat through the atmosphere suddenly reversed direction creating a catastrophic cooling trend? Suppose over a period of 25-50 years, the glaciers advance from the north and the tips of mountain peaks settling over much of northern Europe, Asia and North America. Heavy rainfall batters the Middle East, Sahara and Australia while much of France, Germany and Russia lie frozen under a blanket of permafrost. In Central and South America, the rain forests die back to reveal a much more hospitable savannah. The sea level also drops by anywhere from twenty to over a hundred feet. What would the worlds political boundaries look like by A.D. 1650?

[Count Dearborn]

So, the Little Ice Age shows up early? (OTL, approx. 1350-1850)

[MarkA]

Not a Little Ice Age but a major one!

[JLCook]

And how fast would they march south? During the last one, the ice was upt to 3kms thick, but that was all formed by snowfall, so, I'm asking, how fast could one develope? Geologiclly significant time frames can range from thousands to tens of thousands of years?

Also, I think that when the last one melted, it still likely took thousands of years for all of it to recede. "Officially" the last one ended 14,000 years ago, but events, such as the collapse of the Bosphorus straights was only about 5000bc, some 7000 years after the ice age was "officially" over, yet the rising meltwater still took 7000 years to raise sea level to the point that the Black Sea flooded.

Creating a new ice age might be assumed to happen overnight, but what if formation of one took 10,000 years? would any of us ever even notice?

[MarkA]

For an Ice Age to occur 'overnight' ( I assume you do not mean this literally) a massive amount of heat would need to be generated. While this may seem contradictory, for snow to fall a large amount of evaporation needs to occur first. Also it would help if the earth was covered in a blanket of dust, ash, soot, etc to block out the sun. Thus an asteroid impact or volcanic eruptions need to happen.

We are in the process of entering a new Ice Age but global warming has masked it.

[Flocculencio]

We are in the process of entering a new Ice Age but global warming has masked it.

Hooray! :D

[JLCook]

for about 7000-8000 years now. IF the new Ice Age arrives on schedule, it should be full blown and threatening Des Moines in about the year 12,000AD. Do you think that will be an immediate problem and concern?

[MarkA]

for about 7000-8000 years now. IF the new Ice Age arrives on schedule, it should be full blown and threatening Des Moines in about the year 12,000AD. Do you think that will be an immediate problem and concern?

Exactly! So I do not think we should be too worried do you?

Unfortunately, however, it is coming too slowly to counter the effects of global warming. The latter is of far greater immediate concern.

[carlton_bach]

The beginning of a new ice age would certainly not drive glaciers into Saffron Walden and Aix-la-Chapelle overnight, but that dopesn't mean the people affected can stop worrying. There is some evidence that climate 'tipping points' can entail shifts of several degrees centigrade over a few decades. The glaciers take forever to build up, but something like this majorly f***s up microclimate patterns. Forests die, fields get washed out or dry up and blow away, wheat, grapes and olives, dates and rice won't grow one year, permafrost turns to bottomless bog, fish migration patterns change, safe harbours silt up, rivers flood or dry up to a trickle - and people starve. AD 1000 is a bad time for this to happen, with Northern Europe just entering intensive agriculture. If the new system proves so unsuited to new realities, the population will not expand to anywhere near OTL levels and much of Britain, France and Germany will end up with societies and political significance similar to OTL Scandinavia.

[Max Sinister]

This might even destroy human civilization, i.e. throw us back into the times of hunters and gatherers. Maybe a bit might survive around the mediterranean (after the dust has settled because of Germans, French and Brits wandering south), maybe even in African states (Timbuktu, Mali?) Then there are the Asian civs...

[chunkeymonkey13q]

Yes, that is similar to what I was thinking, only I doubt whether the birth of a new ice age would cause a complete regression to the hunter gatherer stage, for all people living everywhere. One of my main goals for this timeline, however, was to prolong the Dark Ages, from which Europe was just beginning to emerge during this time. There would definitely be serious environmental problems, because although this cooling is not taking place overnight, it is happening fairly rapidly, wrecking havoc on the nations and peoples of this time. Many of the inhabitants of northern Europe, America and Asia would no doubt be forced southwards probably by the millions. At first it would not be obvious that anything had changed for the worse, as it would take a while for the northern seas and rivers to become covered by ice flows and the snowfall to build up over the plains. As time passed, however, the land would become more and more difficult to farm, mine and build on leading to a mass migration to the south. This change would probably be highly beneficial to such peoples as the Aztecs and Mayans, who would gain a much more hospitable environment as the rain forests died away and to the Muslims, who would inherit a desert slowly turning green.

[jolo]

Something to think about: If in the year thousand, a really bad ice age had started (let's say a sudden drop in temperature due to some ocean currents or the likes changing and affecting the whole climate system, and a slow accumulation of ice around the poles), the sea levels would go down a little each year.

As more and more water is stuck at the poles, the Earth even changes her looks: the sea beds rise, the ground under the glaciers sinks.

Therefore, the land mass gets bigger and bigger, the oceans smaller and smaller. By today, everything under less than 200 m of water should be dry - that may double the available land mass, despite some losses in the north (didn't look up the exact figures).

The new climate system wouldn't even be hostile: The glaciers would supply giant rivers and lakes everywhere, and the larger distance to any ocean might mean fewer water is washed to the oceans by rivers, so that there are even fewer or smaller deserts than in OTL.

Therefore, we might even have a faster development because of more land, more ressources, more interaction between the people, and so on.

[chunkeymonkey13q]

It is true that an ice age could very well could be highly beneficial—but only for some cultures. The Aztecs, Mayans and Incas who were restricted by the great jungles which surrounded their civilizations would be free to grow and expand almost without limit, as the rain forests were replaced by savannah. The Muslims, who in our timeline seized control of a vast desert, would find themselves the masters of a great fertile plain and so would perhaps settle down in favor of a quieter life.

On the other hand, much of Northern Europe, Asia and America would suffer as the land became buried by huge drifts of snow. Most of England, Northern France, Germany and Russia would become too cold to support a large population, while countries located even further north would be completely inundated. These people would then flee to the south as their farmlands became too difficult to farm. This would perhaps be like a “second wave” of barbarian invasions, a follow up to what the Romans dealt with five centuries previously. How would the surviving nations of Europe handle such a large influx of people? Certainly this would radically change the outcome of history, but how?

[Kidblast]

here's my map of roughly around 2000 a.d.

red= christianity
yellow= china and tributary states
green= caliphate