Why we should care about huge ice world to our south
What do we picture when we think of Antarctica? Big, white, cold . . . and penguins probably figure too.
We might also think the frozen continent, several thousand kilometres to our south, matters little to our increasingly busy lives.
Why should we care about what’s happening in the coldest, driest, windiest and least-inhabited land on the planet when we’re preoccupied with trying to get the kids to school, or keep the mortgage account full?
The answer: What happens down there will eventually hit home here — and our descendants will pay.
If you drive to work along Auckland’s Northwestern Motorway, you might be alarmed to know a 2011 storm that submerged much of it would happen as often as every two years with a mere 40cm of sea rise.
Under the best projections we have at the moment, we’ll likely get somewhere between 30cm and a metre by the end of the century.
So even if we end up falling halfway on that spectrum, the big 2011 storm that we’d consider a once-in-a-century event now would become a monthly occurrence. What’s it to do with Antarctica? The continent bears not just a metre of equivalent sea-level rise in its icy stores, but nearly 60m.
Worse still, we simply don’t know all we should about how Antarctica might respond to climate change, making it something of a big white boogeyman to scientists drawing up future sea-level rise models.
In fact, it barely factors into present Intergovernmental Panel on Climate Change’s projections.
IPCC’s most recent report, published five years ago and soon to be updated, said only the collapse of marine-based parts of the Antarctic Ice Sheet, if triggered, would cause global mean sea level to rise much above the likely range this century.
Yet one of its authors, glaciologist Professor Tim Naish, of the University of Victoria Wellington, said more recent studies suggest we’ve hugely underestimated the ice sheet’s risk of collapse.
A paper co-authored by Associate Professor Nick Golledge even indicated the tipping point would be crossed nearer to 1C of warming.
And that’s the line 200 or so nations, including ours, have drawn in the sand with the Paris Agreement.
As Climate Change Minister James Shaw and other world leaders meet in Poland this week for another post-Paris summit, the possibility that their carbon-cutting efforts might not be enough to save the polar ice sheets from collapse should be cause for unease.