Not that I don’t care, but ever since An Inconvenient Truth made the polar
bear the iconic image for climate change, it’s become a distraction from the
real debate.
Take this piece of logical legerdemain from
Matt Ridley. Admitting through gritted teeth that actually, really, oh-all-right the Arctic sea ice is retreating, he plays a misdirection
game: “In the Holocene Optimum there was no collapse of the polar-bear
population”.
Keep calm and carry on, people, the polar
bears will get by somehow.
That, of course, ignores two itsy-bitsy
ever-so-tiny details.
- 1. Polar bears and arctic foxes are only so-so as a proxy to answer the question “what impact would an ice-free Arctic have on species in the region?” Ridley somehow manages to overlook species, like the muskox and the steppe bison, that may have suffered a population collapse in the Holocene. It’s odd that he’d miss these examples, since he’s a zoologist.
- 2. The survival of the polar bear is not a benchmark for the impact of warming on human society.
Ridley ends with this red herring:
“The sea-dominated Southern Hemisphere is
certainly warming more slowly than the land-dominated Northern Hemisphere, but
it has still been warming. If warming is supposed to be "global,"
shouldn't sea ice retreat at both ends of the world?”
That’s a misleading question – since it’s been
answered. Ridley seems to be placing a bet that his readers don’t know this.
His readers don’t realize that the Antarctic is land, not sea; that the freshening
of the Southern Ocean allows it to freeze more readily.
Most importantly, if all of the Antarctic
ice is taken into account – both land and sea ice – the Antarctic ice cap, like
the Arctic, is shrinking.
