The operative word is could.When hunters arrived in North America and drove mammoths and other large mammals to extinction, the methane balance of the atmosphere could have changed as a result, triggering the global cool spell that followed.
"It is conceivable that this drop in methane contributed to the Younger Dryas cooling episode," says Smith.
The operative word is conceivable. Is this the sort of crap that science has become? The reason it's called prehistory is because there was no one at the time around capable of recording what wass going on -- lack of writing, etc. Which of course leaves it open to all sorts of speculation, including this sort. Editorial standards need to be raised. I know, I sound petulant. But this kind of stuff is really becoming tiresome. Or maybe just ts being taken seriously is.
They're making some fairly absurd leaps in their logic, I agree.
ReplyDeleteSomething these otherwise smart people missed was the sheer scale of the matter. A few thousand hunters vs. a few billion industrialized people: The effect on the environment can't be compared between those two examples, because the scale of effect involved is orders of magnitude different. Going back in time to look for examples of anthropocentric climate change is speculative to the point of being inductive reasoning, rather than deductive. "Could be," sure; but probably not.
There are lots of ways of measuring events at a time before people were around, or when people were around but were capable of making meaasurements, or making them on some material or in another way in which they didn't get destroyed subsequently.
ReplyDeleteThere is absolutely nothing wrong with using words like "could" or "conceivable" if you aren't sure about something. Scientists do not deal in certainties all or even most of the time, any more than anyone else does.
As I have written so many times before, it is easy to criticise from an armchair.
There's a very good news feature in nature about popular myths about climate change, which I'm sure I have pointed to before.
Sorry- correction to my middle point, I meant to type "weren't"
ReplyDeleteor when people were around but weren't capable of making measurements
Fair points, Maxine. The problem is when, in the mainstream media, "could have" so often gets turned into "did."
ReplyDeleteHaving been trained as a scientist (geology, some medicine), I tend to be skeptical about ALL such claims until I can see the evidence and judge for myself. Of course science does not deal in absolute certainties—but neither should it deal in speculation without some evidence upon which to build speculation. I see none of that here, so far.