Jim_Smith
New
One of the arguments used to argue that global warming is caused by humans is that the rate of change is happening faster than can be explained by natural causes.
An episode of Nova about the cause of the extinction of large North American mammals 12,900 years ago tells of a two year period where the temperature fell 18 degrees Fahrenheit.
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Measuring oxygen isotopes in ice cores provides information on the temperature of the climate at the time the ice was formed.
An episode of Nova about the cause of the extinction of large North American mammals 12,900 years ago tells of a two year period where the temperature fell 18 degrees Fahrenheit.
The Nova documentary explains that this episode might have been caused by a comet impact. However:the ice cores proved that the Earth's
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climate can change extremely rapidly
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sophisticated molecular analysis of the
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ice can reveal the temperature at the
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time it formed the ice from this time
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animals went extinct shows a very
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unusual change temperatures plummeted it
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happened so fast when you think about it
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it's it's unbelievable it's a complete
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change in the state of the climate
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system it would be the equivalent of
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going from maybe to three months of
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winter in in northern New England let's
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say to 11 or 12 months of winter
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throughout the year
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in possibly less than two years the
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annual temperatures in North America
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dropped up to 18 degrees Fahrenheit
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which may not sound like a lot but the
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last time it got that cold in what is
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present-day Chicago it was buried under
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a mile of ice
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throughout much of the world climates
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changed some places got colder others
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dried out causing more fires
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was this sudden climate change
Gary Haynes says that's true [that animals went extinct because of climate change] but there
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were other similar periods of climate
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change
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Measuring oxygen isotopes in ice cores provides information on the temperature of the climate at the time the ice was formed.
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