Extreme marine heatwaves to hit New Zealand waters

While warmer water temperatures may be good news for Kiwis hoping to have one last dip before Winter, it can have devastating effects on our marine ecosystems.
While warmer water temperatures may be good news for Kiwis hoping to have one last dip before Winter, it can have devastating effects on our marine ecosystems. Photo credit: Getty Images

Don't pack away the speedos and boogie boards just yet, as a marine heatwave hits most of the country next week.

While sea surface temperatures are getting cooler as we inch closer to winter, The Moana Project found apart from the Otago Peninsula, all of New Zealand is expected to experience an extended period of "extremely warm" ocean temperatures.

The project found Wairarapa is currently experiencing a severe marine heatwave with temperatures similar to Summer.

The region is sitting at 17 degrees,  2.5 degrees above average temperatures for this time of year. 

However this summer, the Wairarapa region experienced warmer than usual waters as a consistent 81-day long marine heatwave from November 2021 to February 2022 hit, with water temperatures at one point hitting 19 degrees.

Areas such as the Bay of Plenty, Taranaki, the Cook Strait and the Banks Peninsula are all currently enduring strong marine heatwaves, with the Chatham Islands and Stewart Island are expected to join them early next week.

While warmer water temperatures may be good news for Kiwis hoping to have one last dip before Winter, it can have devastating effects on our marine ecosystems.

The Moana Project, which studies marine heatwaves around New Zealand, said New Zealand ocean life has evolved to thrive in cooler seas, therefore, the higher temperatures can have huge negative impacts on local ecosystems.

The project said the heatwaves also pose a threat to aquaculture and the fishing industry, which is worth more than $4 billion annually.

The study is investigating trends in heatwaves and which factors are causing them, as well as how to better predict when they will strike out waters.

"As climate change affects our oceans, marine heatwaves are expected to become more frequent, intense and longer-lasting."