Had PBS on for background noise, a Nova episode about exploring blue holes in the Bahamas. Which led into climate change; NATURAL climate change.
Short version: dust found in a layer traced to the Sahara; the dust layers corresponded to layers in a stalagmite indicating big, fast-occurring warming, in some cases big temperature and sea-level rises in as little as 50 years. And theorizing that the droughts in Africa over the last few decades, and the dust storms, could be indication of a warming cycle about to kick off.
So my brain started spinning with some questions and thoughts:
I wonder how the past warming periods they're seeing signs of correspond to sunspot activity?
Wonder if any way to determine how long the droughts preceded the beginning of the warming period, if the theory is correct?
And, the big one,
If the theory is correct, it would be further proof that the warming of the recent past was primarily, if not completely, natural cycle, thereby shoving a stake in the heart of AGW.