Comment permalink

While most South Islanders were shivering through the coldest snap of the winter so far, the latest grim assessment of Earth’s warming climate was being delivered on the other side of the world.

The Intergovernmental Panel on Climate Change’s (IPCC) most recent findings — more properly known as the Working Group 1 report covering the science of climate change — state that anthropogenic warming is already having a substantial effect on weather and on climate extremes.

Since the last such report was published eight years ago, it has become increasingly clear to the thousands of scientists and experts on the panel that the frequency and severity of heatwaves, of torrential rain and of drought is changing for the worse. The evidence has also strengthened that this is caused by human activities.

The climate is changing so quickly — faster than was even anticipated in an IPCC Special Report just three years ago — that average global temperatures are now 1.1degC warmer than they were before the Industrial Revolution. The important and dangerous marker of 1.5degC of warming has crept even closer than might have been imagined, panel members saying it is now on the horizon and could be reached within the next two decades, unless huge changes are made right now.

Every 0.5degC of global warming leads to "clearly discernible increases" in the intensity and regularity of flooding, drought, forest fires, heatwaves and severe storms.

Nobody who has lived in New Zealand for more than 30 years or so can honestly say they have failed to notice how the weather is different from when they were younger.

There are fewer frosty mornings these winters than there were several decades ago, and there are more summer days on which the temperature climbs into the thirties. When we get a rainstorm or snowstorm, it is more intense and can occur outside what was traditionally its season. The influence of warmer air, warmer oceans and "marine heatwaves" cannot be denied.

In 2018, University of Canterbury academic Prof Bronwyn Hayward, a member of the IPCC writing team and a lead author on "Special Report 1.5degC", warned there needed to be an end to the "magical thinking" — that somehow it wasn’t really happening or that things would come right.

She is now warning that we must not get lulled into another piece of magical thinking, believing that the boffins in Silicon Valley and the like will come up with some amazing piece of technology to save us. Instead, we need to digest the fact that the best way to flatten that global temperature rise curve and protect our world is to reduce energy consumption and emissions, if we have any hope of keeping the increase under 2degC, as laid out by the Paris Agreement.

This week’s report says across the southern hemisphere the high-pressure belts are expanding towards the poles. For New Zealand, that means more rain and snow in the west and south during winter and spring, and less elsewhere. In the summer, eastern districts are likely to have more rain while the west is drier than it has been traditionally.

These latest findings are more grist to the mill. Let’s face it, we have known about the changing climate for decades. Since then there has been prevarication, disinformation, general apathy and a hope that either the science was wrong or someone would wave a magic wand and make it all right.

New Zealand was in the vanguard of warning the world about climate change. Wellington scientist Dave Lowe alerted those who were listening to a burgeoning crisis more than 40 years ago, when he spotted the rise in carbon dioxide in the southern hemisphere’s atmosphere.

There was plenty of notice. But, until recent years, what has really been done?

Reading this and the latest IPCC report, the climate-change naysayers will be sharpening their pencils yet again. Faced with a firing squad, at what point would they be convinced the guns are genuine? There should no longer be any doubt. Action is needed now.