Global Cooling? It has happened before

The Earth has obviously gone through countless, remarkable periods of both warming and cooling. What should give us pause for thought is these occurred long before man began burning lots of fossil fuels and adding carbon dioxide to the atmosphere. We're not even really sure warming is even occuring and there are obviously factors at work other than man and our pathetically minor input of carbon dioxide.

From a friend, here is a summary from a presentation on the television History Channel about the affects of what is now known as "The Little Ice Age".

A gem off the History Channel this morning.

Consequences of the
Little Ice Age.
It began in the 1300s, wiped out the Vikings in Greenland,
defeated the Spanish Armada, keeping England English, spread potatoes across
Europe, won our Independence, defeated Napoleon, started our westward migration, and created Frankenstein.
It was believed triggered by an increased incidence of Krakatoa-scale volcanic eruptions: 5 per century as compared to the usual 1 per century. And on top of
this: 5.April 1815 came the explosion of Mt Tambora
on Sumbawa, Indonesia. 36 cubic miles of debris were sent up to 15 miles
into the stratosphere. This is 100x the ash of St Helens.
A dusty fog hung all summer over N. Europe. It snowed. In Hungary the snow was brown. Agricultural resources already devastated by Napolean's march into Russia were ruined by the cold. People starved.
As the "year without summer" began in 1816, Percy Shelley, his 19yr old wife Mary, and their friend Lord Byron, went on vacation to Lake Geneva. But it was too cold and grim to go outside. So the three decided to amuse themselves indoors w/ a
contest to see who could write the scariest story.
Mary won.

The potato was brought to Europe from the new world by early Spanish
explorers. But it was culturally out of whack with traditional staples and
was quickly opposed by the clergy who called potatoes the "devil's crop". People starved when crops failed but potatoes were still avoided.
Then came the 30 Years War. A traditional strategy of warfare in
those days was the burning of crops. This destroyed surface crops like the
grains. But potatoes live underground out of touch of burning, and
freezing. Hence, thanks to the 30 Years War, potatoes
finally became accepted as a staple in Europe.

One consequence of global warming is global cooling, considered the bigger threat to survival since it wipes out food supply. The warming causes the cooling owing to glacial snow melt changing ocean salinity which interrupts temperature conveyor currents that currently keep the northern latitudes warm.
Pentagon commissioned a study of the coming ice age scenario. This is raising concern about threats to world order. It is based upon an actual catastrophic temperature change of 802 yrs ago that created anarchy worldwide and changed history. Temp dropped 9 degrees in one year. Rivers froze, crops failed, people starved, nations were drained of resources. Breakdown of societies resulted.
Skirmishes, civil wars, and invasions broke out over resources and water.
This time around it will be worse.
Pentagon is interested to determine how the destabilization will play out and what role the U.S. will have in maintaining world order during the chaos. Likely the U.S. will be soley responsible and plans need be on the shelf.
China a volatile flashpoint. By the scenario, civil war erupts. Chinese Army threatens to invade Russia for it's gas. There will be virtual full scale civil invasion of the U.S. from Latin America. U.S. Navy heads for Gulf to protect Saudi oil resources.

It is not yet clear whether we are going into hyperwarming or hyper cooling. Arguments still out. Behooves to be more cautious w/ possible human influences on global environment