Every one hundred thousand years we have a period of glaciation that is called an "ice age". A hundred thousand years is approximately 5 thousand generations or over a thousand lifetimes. They are on a time scale that is well over our lifetime. We therefore cannot really "have one". Our ancestors lived through them and our descendents probably will as well.
During the last one, Neanderthals inhabited the parts of Eurasia that was habitable. They were a cold adapted species. If we have another "ice age" most of Europe and North America would become extremely inhospitable.
Ice ages are also known to scientists as "Glacial Ages".
In Earth's past we've had many, most early ones were because of some interruption of sunlight getting to earth's surface. These interruptions might be heavily bodies (comets?), or impressive geothermal events (hundreds of volcanoes contributing ash into the upper atmosphere at the same time). It causes a reduction of ambient temperatures to where fields of ice will form. The scary part when this happens is that ice is highly REFLECTIVE of sunlight and when a big field of ice occurs, it cools the surrounding areas, and they get cold causing a chain reaction which develops into an Ice Age.
Once the reaction takes its course and settles down to stabilize, the earth will then start warming back up, but the warm-up time is VERY gradual and will take centuries because the ice is still reflecting and becoming a "radiant barrier" keeping the surface cool.
When I took an environmental science class (while in engineering school) we learned of weird theories like the "Milankovitch cycles". This guy ran a bunch of numbers and predicted that ice ages would "try" to occur every 22,000, 41,000 and 100,000 years. So it's not likely you or I will see a true Ice Age, but our distant descendants will.
Ice ages happen fairly rapidly, (in 1775-1776 we had a mini-ice age). It had an impact on western history as we know it. Napoleon tried to attack Russia and got stopped in massive blizzards and was forced to retreat, losing thousands of troops. No winter has been that bad ever since. George Washington had to navigate past ice bergs the Potomac river with his rag-tag troops and attack the Prussians in the revolutionary war. The Potomac has NEVER been that cold since. But years before 1776, the earth's weather was much warmer.
That's an example of having a very minor ice age, but an ice age none the less.
It is feared that global warming issue will trigger a SERIOUS ice age.
When I took the environment science class (I'm not an environmental scientist), the professor said that earth is normally a very warm planet. The evidence of dinosaurs and fossil fuels are indisputable data that in order to create as much as we have, earth needed to have lots of sun and water.
According to class, earth is warming up to it's normal temperature, and it will happen regardless of whether humans existed on earth or not. We may be contributing to the rate of how fast the temps rise, but that's about it.
With changes in earths orbit, and the angle that earth spins and other things, changes come about every 100,000 years or so, that cause our earth to receive a little less sunlight, which allows the ice at our poles to grow, as they grow they reflect more sunlight back to space causing the earth to cool, and as it cools, more ice to grow, eventually our earth becomes cold and dry, with large deserts and lots of ice mainly in the northern hemisphere (as that is where most of the land is)
An ice age would not be able to support all our populations that we have now.
a global temperature average of about 5C less than today- resulting in more ice, lower sea levels and buildup of large ice sheets in polar latitudes. It's triggered by orbital changes and tilt of earth.
don't bet on one anytime soon. there has never been an ice age with the current greenhouse gas concentrations.
well we Finns are gonna be in a deep **** if we get ice age, because whole ******* Finland would be covered with about 10 km of ice.
most scientists agree that we are still coming out of one. Yet at the same time, they complain about global warming. Guess it depends on who's funding their studies.
please make it simple and easy to understand
