Surf, sand, and rising tides
Raglan’s Ngarunui Beach is crumbling.
Winter storms and angry waves have attacked the shores and now the escarpment, where erosion has occurred, is nearly two metres tall.
It’s not just West Coast beaches that are affected, erosion is eating away at New Zealand’s coastline, Waikato University Professor Karin Bryan said. Bryan is researching the impact of climate change drivers such as changing sea levels and storm surges on our coasts.
She and her team have studied several beaches around the country, including Tairua, Pauanui, and Ngarunui in Raglan. Wave events and the El Nino and La Nina weather systems are responsible for recent erosion at Ngarunui but the country’s coasts are varied, which means there are different climate drivers for each beach.
‘‘We’re an unusual country – waves from the North Pacific, the Southern Ocean, the Tasman Sea and even the Indian Ocean affect our wave climate,’’ Bryan said. ‘‘The
most important point from the research is that the sea level is rising and the coast is changing.’’
Bryan said climate change and the impact on the coastline is a topic that New Zealanders don’t take
seriously and that needs to change.
‘‘When I visit Whitianga and look at the frontal sections there, those really are going to get inundated in the next 30 or 40 years.
‘‘People are going to have to lift their basements up or retreat and I don’t think we’ve really thought about that properly in New Zealand.
‘‘At some point, what’s going to make us actually do something is the insurance companies. It’s going to be increasingly hard for people to get insurance in areas where they’ve been warned that it’s flood prone.’’
We’ve literally got billions of dollars of savings wrapped up in property that is at the frontier of the coast, Bryan said.
‘‘It’s somewhat frightening.’’ The three year project is a collaboration with a marine research company called eCoast, Dr Terry Hume, a marine geologist and coastal oceanographer, and Dr Jordan Waiti, who is speaking with iwi about their perceptions and values around surf breaks. A lot of the monitoring is done by remote satellites and the data is then collated by local councils. From the research, the team will deliver a set of guidelines on what to collect to monitor surf breaks.
But ultimately, Bryan hopes it will encourage New Zealanders to think more critically about the coast. The project is due to wrap up in October.
‘‘We’re an unusual country – waves from the North Pacific, the Southern Ocean, the Tasman Sea and even the Indian Ocean affect our wave climate,’’
Waikato University Professor Karin Bryan