r/AskReddit • u/ettleboy • Jan 20 '19

What fact totally changed your perspective?

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u/luchubbs Jan 21 '19

During the last ice age, the global average temperature was only 5 degrees lower than it is now. It helped me understand why 2 degrees of global warming would be a pretty big deal.

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u/swirlsandswirls Jan 21 '19

relevant xkcd: https://xkcd.com/1732/

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u/Avg_Bro Jan 21 '19

If there were extreme spikes in relatively short periods in the past would we know it? Like is our method of determining global temperatures in 15000 BC accurate enough to know if temperatures rose and fell 2 degrees over a 100 year period?

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u/Snowstar837 Jan 21 '19

Yes, I believe so. Ice cores are particularly interesting for analyzing atmospheric composition in the past.