An earthquake is not related to the climate and neither is  a flood that was  'caused' by poor land management.  The last 8 years we've seen a lot of that.
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I never said climate change could never be caused by humans. It simply has not been proven that it is. I think if we blew off all the nukes there are in the world at the same time, it might temporarily cause a  'nuclear winter'  Then again, that's another unproven theory. Some things  we don't know for sure and may never know , while some other things we only have a partial understanding of.  Aristotle said, "The more you know, the more you know that you don't know."  That would be just as true today, I think.
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What is not a theory or 'unknown'  is what we already know  has happened. The climate has changed in the past long before man was ever on earth. It would change again with or without us. We simply are not as influential as some might imagine or theorize us as being.