Peter Meecham / Stuff
Water surrounds Shelswell Rd on the outskirts of Westport after floodwaters flooded the area.
We can expect more intense precipitation events like the one that hit the South Island as the globe continues to warm, climatologists say.
Winter storms in New Zealand are not unusual, climatologist James Renwick said, but it was the intensity of rainfall over parts of the South Island over the weekend that caught his attention.
“We have heavy rainfall all the time, but it’s the volume of water falling from the sky this time around that is unusual.
Peter Meecham / Stuff
Aerial footage taken on Sunday afternoon shows how much flooding remains in the greater Westport area.
“It’s a sign of climate change related to warmer air, which brings more humidity and that’s where the water comes from.
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“You are much more likely to have a weather event with a warmer climate.”
Renwick is Professor at Victoria University in Wellington, Director of the School of Geography, Environment and Earth Sciences.
He said the major rain event in Germany, along with the storm in New Zealand, was “striking” but more a coincidence than a link.
“We have precipitation and storms all over the world at the same time.
“It’s the middle of winter here and the middle of summer in Europe, and it’s striking that it’s been so wet in both places at the same time.
“But I wouldn’t draw any conclusion.”
Renwick said if June was the hottest month on record for New Zealand, more attention should be focused on “global warming as a whole”.
“The water that has fallen on the country in recent days would have come from afar.
“The winter has been hot, the globe is getting warmer all the time, there is more humidity in the atmosphere, so yes, we will see more.
“But every time it rains, it won’t be a flood. I can say that we roll the dice towards heavy precipitation by increasing the temperature. “
He said the warming will continue until the emissions stop.
“We have the power to stop, we just need to use it.”
Climate change scientist and researcher Jim Salinger agreed that the mild conditions of our winter had favored more humidity and more precipitation.
“This is what we are seeing in the Buller area now.”
He said various capture groups had confirmed that this was a 100-year event.
“It is very difficult to predict if this will continue, but we have global warming that has continued and in a way, it has contributed to it.”
Salinger said that although there had been property losses among those affected by the South Island weather event, the loss of life was nil.
“You compare that to what is happening in Germany, there is something like 130 people who have perished and many more are missing.
“Our rivers tend to fill up very quickly because they flow from the mountains… but our weather forecasts are very good and we can predict them in advance.
“The Buller region was able to declare a state of emergency before the storm hit, which was great.”
Salinger, who also works at Victoria University, said the hottest June record suggested global weather conditions were changing “fairly quickly” now compared to a few decades ago.