re: #133 Pythagoras

Your reasoning is sound. Since high CO2 makes the current scenario different from 1k years ago, the fact that it didn’t tip then does not prove it won’t tip this time.

For what it’s worth, the tipping mechanisms mentioned, say, here:

[Link: www.pnas.org…]

are almost all totally a function of temperature or humidity. CO2 does not play a direct role.

But, basically I concede the point — a warmer MWP does not PROVE that we’re not about to hit a tipping point.

I would, however, claim that the burden of proof belongs with the people who claim we must make major changes to prevent their predicted catastrophe.

Yes and no. The people arguing for action now need only convince the jury that big problems are a reasonable possibility. That would make precautions prudent. We don’t have to prove that big problems are inevitable. We shouldn’t claim that we know for sure that they are, when really, that cake isn’t iced yet.