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Roger Weller, geology instructor
by Sam Yang
The Next Ice Age: Coming Soon?
there have been some speculations about whether or not Earth will enter into a
new Ice Age before the next century. Iíve taken it upon myself to get to the
truth behind this rather apocalyptic weather forecast.
What is an Ice Age?
An Ice Age
is a distinct time during the history of Earth when a majority of the continents
of the planet was covered by glaciers. To date, there have been at least 5 major
Ice Ages on Earth.
What causes it?
is more than one theory about the origins of an Ice Age, it is most likely
caused by variations in intensity of heat coming from the sun when a phenomenon
called the procession of equinoxes occurs. During this phenomenon the position
of the Earthís elliptical path around the sun changes, affecting the amount of
sunlight that strikes different parts of the planet. Because of this phenomenon,
there are periods when the summers on Earth are cold enough to have preserved
remaining snow from the previous winter. Consequently centuries pass and ice
sheets are formed across the planet.
How long does it last?
believed to last around 12,000 years at a time, a definite or more accurate
estimation has been met with differing opinions: some say tens of thousands of
years and others say hundreds of thousands of years (It would be safest to
assume an Ice Age lasts somewhere in between).
So when will the next Ice Age be?
Another Ice Age is inevitably due, but not any time soon. The last Ice Age
occurred roughly 11,500 years ago. Although the next Ice Age was previously
predicted to be in about 1,500 years, we are now finding that because carbon
dioxide emission into the atmosphere is at such a high level the next Ice Age
may be delayed further by another thousand years. Blame it on global warming.
However, as speculations on further delay will inevitably change, the point to
take from this is that most of us will not be alive to witness another major Ice
Age on Earth.