New Zealand’s Ministry for the Environment has warned hundreds of thousands of homes face a rising flood threat as the country’s seas warm faster than the global average.

Ten ministry and Stats NZ have released the latest Our Marine Environment 2025 report which highlighted how climate change and human activity are putting increasing pressure on the country’s coasts and the ocean – affecting communities, industries, and ecosystems across the country.

“For many people, the sea is part of daily life – whether through work, recreation, or cultural connection. This report brings together the best available evidence to show how that environment is changing, and why it matters,” says Alison Collins, chief science advisor at the Ministry for the Environment. “Continuity in environmental reporting is essential. It allows us to track trends over time, identify emerging risks, and make informed decisions because we know the challenges and can build resilience for the future.”

The results of the report concluded:

• 219,000 homes are already in flood-prone areas, representing $180 billion in assets.
• By 2060, 1,300 coastal homes could face major damage from extreme events.
• Warming seas and ocean acidification are affecting fisheries and aquaculture, which contribute $1.1 billion directly to GDP, an additional $1.1 billion indirectly by stimulating the non-marine economy, and support more than 14,000 jobs.

“It helps us track trends, identify emerging risks, and plan ahead. That’s how we protect what matters now and keep options open for future generations,”  added Collins.

Other findings include:

• By 2022, 428 non-native marine species had entered New Zealand waters, with 266 establishing populations.
• In 2023, approximately 219,000 residential properties were in coastal inundation and inland flood zones, representing $180 billion in assets.
• Wetlands, dunes, and native vegetation that help buffer against flooding and erosion are being degraded or replaced.

Between 1982 and 2023, New Zealand’s sea-surface temperatures in its four ocean regions increased, on average, 0.16 to 0.26 degrees Celsius per decade, and its rate of ocean warming outstripped global averages by 34%.

Coastal waters are also warming faster than the global average, it said.

The report drew on a wide body of evidence, including peer‑reviewed research, government reports, mātauranga Māori, and official statistics. It was independently reviewed by subject‑matter experts to ensure the findings are robust and reliable.

“The coastal zone is under a real squeeze … and the importance of that coastal environment is absolutely critical – it’s what we rely on in terms of our homes, our communities, our livelihoods and ultimately our connection to place,” added Collins.

Some regions will experience a rise of 20cm to 30cm in sea levels by 2050, a tipping point for some communities, Collins said.

“Sea levels that reach that height mean that a coastal storm that used to happen every 100 years could start happening every year,” she said.