Comment: Just because there hasn't been (apparently) the warming increase

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Just because there hasn't been (apparently) the warming increase

recently doesn't mean there isn't significant (and scary) stuff
going on. Nor that human activities aren't influencing what's going on.

For instance, it's pretty clear that acidification of the oceans is occurring
on a significant scale - with potentially catastrophic effects on ocean ecology,
food chains & such:

It's also become a lot more clearly understood that while there are long
term cycles that have been fairly regular over scales of tens or hundreds
of thousands of years, it's also become more clearly established that significant
change can occur over centuries, decades or possibly even shorter time frames
once a triggering point is reached.

As kellyicus and others have posted, sudden cooling events have often occurred following
periods of warming - especially in the North Atlantic region (see Younger Dryas and
Heinrich Events)

Good explanation of that and much else in this article:

"Until a few decades ago it was generally thought that all large-scale global and regional climate changes occurred gradually over a timescale of many centuries or millennia, scarcely perceptible during a human lifetime. The tendency of climate to change relatively suddenly has been one of the most suprising outcomes of the study of earth history, specifically the last 150,000 years (e.g., Taylor et al., 1993). Some and possibly most large climate changes (involving, for example, a regional change in mean annual temperature of several degrees celsius) occurred at most on a timescale of a few centuries, sometimes decades, and perhaps even just a few years..."

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