"Report: New Zealand's seas heat up 34% quicker than world average, threatening coastal communities and businesses"

New Zealand’s oceans are warming 34% faster than the global average, putting NZ$180bn (US$104bn) worth of housing at risk of flooding, according to a new report on the nation’s marine environment.

The findings come from the Ministry of the Environment and Stats NZ’s three-year assessment, Our Environment 2025, which compiles data across five areas—air, atmosphere and climate, freshwater, land, and marine ecosystems—to outline the state of New Zealand’s natural surroundings.

The latest report, Our Marine Environment 2025, highlights significant challenges for the country’s oceans and coastlines, marked by rising temperatures, higher sea levels, more frequent marine heatwaves, and increasing acidity due to global warming.

“The effects of climate change are not distant—they are already influencing our oceans and coasts,” said Dr. Alison Collins, the ministry’s chief science adviser, in an interview with CuriosityNews.

“Coastal areas are under increasing pressure, and their well-being is vital—these regions support our homes, communities, livelihoods, and our cultural ties to the land.”

The report outlines numerous risks linked to marine changes, including threats to native species, coastal flooding, damage to properties, stronger storms, and risks to both local economies and communities.

It found that 219,000 homes, valued at $180bn, are situated in coastal flood zones or areas prone to inland flooding, while over $26bn worth of infrastructure is at risk. Around 1,300 coastal properties could suffer severe damage from extreme weather events.

Some regions may see sea levels rise by 20cm to 30cm by 2050—a critical threshold for many areas, Collins noted.

“When sea levels reach that point, a storm that historically occurred once a century could start happening annually,” she explained.

Globally, oceans have absorbed roughly 90% of the excess heat generated by human-induced climate change.

Due to its geographical positioning, New Zealand is particularly affected by warming waters, making it more susceptible to shifts in atmospheric patterns and ocean currents.

Between 1982 and 2023, sea-surface temperatures in New Zealand’s four ocean regions rose by an average of 0.16 to 0.26 degrees Celsius per decade—34% faster than the global rate.

Coastal waters are also heating up more quickly than the world average, the report noted.

Additionally, the Subtropical Front—a biologically and economically significant boundary separating colder subantarctic waters from warmer subtropical waters—has shifted 120km westward. This marks the first recorded change in large-scale ocean circulation around the country.

Collins stated that this shift, driven by rising water temperatures, will have “major consequences” for marine ecosystems, food chains, and species like corals, sponges, kelp, and fish.

The report also highlighted increasing ocean acidity, which jeopardizes marine life and habitats.