NZ climate-related disasters hit record high in 2023

This is Aotearoa’s worst year ever for climate-related disasters, with more than twice the number of states of emergency than any other year, and insurance payouts totalling more than the combined total of the previous 14 years.

Declaring a state of emergency is a critical part of New Zealand’s response to disasters, giving authorities extraordinary powers designed to deliver a swift and effective response.

IMAGE: Robert McLachlan

Eight of the emergency declarations were owing to Cyclone Gabrielle in February, with local emergencies declared in multiple regions, until a national state of emergency lasting 28 days was declared.

The South Island has seen only two states of emergency so far this year, with heavy rainfall and flooding in Gore and Queenstown in September, while the North Island has borne the brunt of multiple extreme weather events.

Northland, Auckland, Waikato, Bay of Plenty, Tairāwhiti and Hawke’s Bay were hit the hardest by Cyclone Gabrielle, and Auckland, Tairāwhiti, and Waikato have also forced into states of emergency because of other severe weather events.

Scientists are in no doubt that the events were exacerbated by rising temperatures caused by climate change, with a rapid attribution study concluding “with certainty” that human-induced climate change was the main driver making Cyclone Gabrielle’s extreme rainfall more likely.

Robert McLachlan, Massey University distinguished professor in Applied Mathematics, says 2023 has been exceptional in terms of global temperature rise.

The global temperature anomaly for 2002-2016 averaged +0.95ºC above the 1880-1910 baseline, while for 2017-2022 it was +1.18ºC. However, for the first nine months of 2023 that was much higher, with the global temperature anomaly +1.39ºC above the baseline.

“So 2023 is highly exceptional and may indicate what a ‘normal’ year looks like in 10 or 15 years’ time.”

IMAGE: Robert McLachlan

McLachlan’s analysis drives home the relentless rise in payouts for climate-related disasters. “The 2004 floods in the lower North Island were exceptionally bad. So bad that the insured damage for the entire year was not exceeded until 2017, McLachlan says. “Since then it has been exceeded every year. The total for 2023 exceeds that for the previous 14 years.”

Going back further, the single most expensive previous event in the Insurance Council’s records was the Wahine storm. “That cost $13.5m in 1968, equivalent to $300m today,” McLachlan says.

The previous government had planned to introduce a Climate Adaptation Bill as part of their package of Resource Management Act reforms, but this was delayed. “Questions of climate adaptation and its financing and risk sharing will now pass to the new government,” McLachlan says.

Jonathan Boston, Victoria University of Wellington emeritus professor and climate adaptation expert, says that 2023 had a “highly unusual” number of extreme weather events. While stressing that he is not a meteorologist, Boston says the weather events were partly driven by the end of three years of a La Niña weather pattern in the Pacific and high ocean temperatures.

“In all likelihood there will not be as many severe weather events over the next year or two, with an El Niño weather pattern in the tropical Pacific. This will likely shift the focus of severe weather away from those parts of New Zealand that were badly affected this year.”

However, over time the costs and disruption from severe weather events will increase, Boston says. “This will be exacerbated by sea level rise, which will intensify coastal erosion and coastal inundation, and the damage caused by storms.”

The incoming government will need to make the right decisions to put Aotearoa in the best position to face challenging times ahead. “It should follow the advice in the recent report of the Expert Working Group on Managed Retreat, of which I was a member,” Boston says.