There are many rhythms and cycles which impact on our planet – one of the relatively long terms cycles is the periodic appearance of an Ice Age. I’m Jim Metzner, and this is the Pulse of the Planet, presented by the American Museum of Natural History.
Right now we’re listening to the sounds of a glacier in Antarctica. During the life history of planet Earth, it’s been covered many times by glacial ice.
Glaciologist Andrew Russell:
“Glaciers provide us with a kind of idea of the pulse of the Ice Ages. Basically we can tell how climate has changed by looking at their fluctuations as they’ve advanced and retreated over the past. We may be able to determine the impact of global warming on these ice sheets and glaciers. So studying past glacier trends can tell us a little bit more about what we might expect in the future.”
By examining core samples taken from glaciers, glaciologists are able to form a picture of how ice has ebbed and flowed over planet Earth in the last few million years. Slowly but surely, we may well be on our way towards the next Ice Age.
Glaciation in the last two million years has occurred in pulses of periods of up to 100,000 years, when we’ve had massive ice sheets, to periods when it’s disappeared very quickly. And then we’ve had sudden blips, much shorter blips of glacial activity which over periods of a couple of thousand years, they have then disappeared. And now we’re going into a period which might be regarded as going to a colder period. Of course, with emissions of greenhouse gases causing the greenhouse effect to be enhanced, we might see that through our own activities as the human race, we may be trying to sort of offset the next Ice Age.”
Pulse of the Planet is presented by the American Museum of Natural History. I’m Jim Metzner.