Don’t worry, it’s not just you.
With global temperatures up 1.1°C compared to pre-industrial levels, it’s getting noticeably warmer throughout the world. Aotearoa New Zealand is no exception.
This summer has been hotter than usual. In 2021 – our warmest year on record – the mercury sat higher than average for nine months of the year, and 2022 hasn’t offered much relief. January saw above average temperatures for the majority of the country, with 34.7°C recorded at Lake Karapiro and fans selling out in Hamilton and Rotorua.
Our record-breaking year and hot summer are part of a trend. Human activities have caused Aotearoa New Zealand’s temperature to increase by about 1°C in the last century, and seven of the last nine years have been among our warmest on record. Yes, now and then we have days where below average temperatures are recorded, but a few cold spells don’t constitute a rebuttal to global warming – on average we’re on an upward trajectory.
We’re also experiencing an increasing number of extreme weather events.
Below normal rainfall has contributed to dry conditions for much of the country, including extremely dry conditions and drought in the North Island. That makes for perfect tinder, clearly demonstrated by the massive fire in the far North that started in late December and is still burning.
At the other end of the spectrum, February started with downpours and flooding on the West Coast, with Westport experiencing its wettest February in 78 years. Broken river banks and torrential rain have damaged homes, flooded farms and left roads impassable, affecting lives and livelihoods on the West Coast. And of course, this weekend saw wild weather bring down trees and powerlines and cause flooding, landslides and swollen rivers in the North Island too, courtesy of ex-tropical Cyclone Dovi.
On top of the human costs of extreme weather events, there are considerable financial costs too. The New Zealand Insurance Council recently reported that 2021 saw insurance claims related to extreme weather events reach new heights. The Reserve Bank expects insurers to respond by adjusting their premiums to reflect rising risk.
Working out the extent to which anthropogenic climate change is responsible for any given extreme weather event is a complicated undertaking, but we can be confident that climate change is playing a role. A recent NIWA study found that the last decade saw 4—5 times more extreme high temperatures than would be expected if humans weren’t warming the planet. And rising temperatures at the sea’s surface not only contribute to marine ecosystem disruptions and on-land temperatures and humidity – they also fuel more powerful tropical cyclones.
So what’s the outlook?
Over the next three months we can expect much of the same – higher than average temperatures in most places and both dry conditions and floods affecting parts of the country. In the longer term, unless we do something about it, climate change will continue to drive an increase in temperatures and extreme weather events. The weather forecasts of the future depend on climate action taken today. Without serious global action, this hot summer will become a familiar story, average temperatures will rise year-on-year, and extreme weather events will continue to take a toll. But by getting stuck in on climate change mitigation, we can improve the forecast.