Glacier melt a call to action

There are some alarming and imaginative ways of measuring the impact of climate change. Glacier researcher Lauren Vargo and climate scientist Andrew Lorrey came up with a good one last year when they calculated that the volume lost from the Brewster Glacier in Mt Aspiring National Park between 2016 and 2019 was about equal to the basic drinking water requirements for all New Zealanders for the same three years.

And, as their media release from Niwa explained, the volume lost is just a small part of the Southern Alps ice storage that has been declining since annual monitoring started in the 1970s. Brewster Glacier is dwarfed by Fox Glacier and Franz Josef Glacier.

Another way of putting it is that 30 per cent of the Southern Alps ice volume has disappeared over the past four decades.

That adds up to a massive 15.9 trillion litres of water.

It’s easy to feel helpless when confronted by such enormous numbers and the slow-moving disaster they describe. Nothing gives you that deep, sinking feeling of existential dread like a problem that has no short-term solution.

But Vargo and Lorrey were outlining a small detail of a much larger and even more terrible picture. The scale of the global problem was revealed in the journal Nature this week.

Glaciers worldwide lost 267 gigatonnes (Gt) of ice per year between 2000 and 2019, which contributed a fifth to global sea level rise. Glaciers, the report found, contribute more to sea level rise than melting ice sheets in Greenland and Antarctica, and the rate of their melt is accelerating. New Zealand’s part looks tiny by comparison. A quarter of that 267Gt is melting in

Alaska, with Greenland, northern Canada and the Himalayas trailing behind.

Yet there is a quirk in the way glaciers melt, as the report explained. While smaller, lower glaciers have less volume, they are more vulnerable to change. New Zealand’s glaciers are melting seven times faster than they were 20 years ago, losing 1.5 metres of thickness per year. Glaciers in the European Alps are also melting faster than the worldwide average.

We knew glaciers were melting, but we didn’t know quite how quickly. There really is no positive side to this story. Around 200 glaciers vanished from New Zealand between the 1970s and 2016. Where there were once 3100, there are now 2900. And along with the rise of sea levels, melting glaciers will lead to reduced river flow and have obvious effects on tourism.

The sad thing is that none of it feels new or, as Vargo told RNZ, even particularly surprising. Climate change reporting often seems to be about finding new ways to frame the same problems. It’s hard not to feel that a certain jadedness sets in with readers and viewers.

But that fatalism should be avoided. We successfully tackled Covid-19 because it was urgent and its threat was obvious, and we were prepared to change our lifestyles, at least for a short time. We need to think about climate in the same way.

Prime Minister Jacinda Ardern was criticised for her unwillingness to make new commitments during a recent climate summit, and the criticism was justified.

This is not the time for caution, and it is to be hoped that the image of rapidly disappearing glaciers, with all their implications for economic activity, including an already challenged tourism sector, might sharpen political resolve somewhat.

Nothing gives you that deep feeling of existential dread like a problem that has no short-term solution.