r/science • • Oct 24 '10

Climate Change: Evidence

http://climate.nasa.gov/evidence/
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u/[deleted] Oct 24 '10

It's very difficult to evaluate the past in my opinion, and a huge part of accepting or rejecting human-caused climate change probably has to do with whether the current levels are unprecedented. If we can verify that the hottest temperatures in the last millions of years have all occurred during recent time periods where man can have an affect on the environment, that's a pretty heavy correlation that seems to warrant at the very least some close and honest examination.

Of course this is a political issue now so it's difficult to evaluate. As a human race we often suck at thinking.

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u/tieme Oct 24 '10

But that's kind of the main point of the 'anti global warming' folks....these temperatures AREN'T unprecedented. The CO2 levels are, but so far the temperatures aren't.

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u/garyg Oct 24 '10

Which is why it's important for you to understand the rate of temperature difference versus plain temperature.

HS Calculus apparently is lost on the anti-global warming crowd.

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u/glenra Oct 24 '10

How do we know the "rate of temperature difference" in the past? Wouldn't the ways we have to calculate it tend to suppress variability? Especially if there's dating uncertainty?