We are descendants of the ice age.

We are descendants of the ice age. Periods of glaciation have spanned the whole of human
existence for the past 2 million years. The rapid melting of the continental glaciers at the end of the
last ice age spurred one of the most dramatic climate changes in the history of the planet. During this
interglacial time, people were caught up in a cataclysm of human accomplishment, including the
development of agriculture and animal husbandry. Over the past few thousand years, the Earth’s
climate has been extraordinarily beneficial, and humans have prospered exceedingly well under a
benign atmosphere.
Ice ages have dramatically affected life on Earth almost from the very beginning. It is even
possible that life itself significantly changed the climate. All living organisms pull carbon dioxide
out of the atmosphere and eventually store it in sedimentary rocks within the Earth’s crust. If too
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much carbon dioxide is lost, too much heat escapes out into the atmosphere. This can cause the Earth
to cool enough for glacial ice to spread across the land.
In general the reduction of the level of carbon dioxide in the atmosphere has been equalized
by the input of carbon dioxide from such events as volcanic eruptions. Man, however, is upsetting
the equation by burning fossil fuels and destroying tropical rain forests, both of which release stored
carbon dioxide. This energizes the greenhouse effect and causes the Earth to warm. If the warming is
significant enough, the polar ice caps eventually melt. The polar ice caps drive the atmospheric and
oceanic circulation systems. Should the ice caps melt, warm tropical waters could circle the globe
and make this a very warm, inhospitable planet..