When is Earth supposed to experience another Ice Age, how often do they occur, and would global warming affect

Question

do they just occur in cycles, not influenced by man, and are the cycles fairly periodic?

Answer 1

"The amount of solar radiation (insolation) in the Northern Hemisphere at 65°N seems to be related to occurrence of an ice age. Astronomical calculations show that 65°N summer insolation should increase gradually over the next 25,000 years, and that no declines in 65°N summer insolation sufficient to cause an ice age are expected in the next 50,000 - 100,000 years."

Global warming is causing the earth to deviate from this cycle on a much smaller timescale, and to a far greater degree. The global mean temperature difference between the depths of the glacial period and, say, 1900 was around 8 degrees C at the poles (where the ice core evidence is). The vast bulk of that change occurred over a short period (perhaps 1000 years).

The trend in the 9000 years since was gradually downwards but always within a degree or so of the mean.

Current Global warming theory predicts a total rise in global temperatures, on top of the 0.8 degrees we have seen over the past 100 years, of around 5 degrees over the next 100 years. This assumes we do nothing to change our rate of use and rate of growth of use of fossil fuels, and continue to release the greenhouse gases that are produced by burning them into the atmosphere. It also assumes nothing happens to make things worse, such as the large-scale release of methane clathrates that caused the permian extinction event.

You should also note that there is no reason the temperature rise should suddenly stop in 2100 - it will continue until we learn to live without releasing CO2 and methane.

So no, global warming will not affect the onset of the next ice age - they are happening on completely different timescales. If, in 50,000 years, the planet has not recovered from man's abuse of it, then the few remaining species can look forward to a welcome cooling and the return of the long vanished ice caps.

Or we could do something about it.

Answer 2

The cycle are periodic and have nothing at all to do with man or even Al Gore.  There are big ones and small ones.   Last one ended about 25,000 years ago, which is just a moment in geologic time.    The ice sheet in Connecticut and Massachusets was miles thick.   Better get a warm coat.

Answer 3

Another 10 million years or could happen next week.  No one knows for sure.

Answer 4

um... we will really never know until it happens.  it's like asking why a weather man can't predict weather... because it's just a guessing game!  Scientists can predict... but be off...  but how are we supposed to know?? we've never been through one before!!