Coastal houses will be washed away, the dairy industry's viability will be threatened, and glacier tourism will be finished - these are among a climate scientist's dire predictions for New Zealand if the world doesn't deal with global warming.

Professor James Renwick, of Victoria University of Wellington, said he was not surprised by Dr Jim Salinger's finding that 2018 was New Zealand's hottest year on record.

"It's consistent with the trend we are seeing all around the world."

He said sea-level rise from warmer water and the loss of ice would inundate heavily populated areas around New Zealand's coast.

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On Wellington's Kapiti Coast, for example, the predicted sea-level rise would carry the Tasman Sea 50m or more further inland. Houses within metres above the current high-tide line, along with sewers, power lines, roads and other infrastructure, would all have to move.

"Houses will have to be moved by their owners or be washed away."

A key warning of the approaching disaster might be the inability to re-insure their homes - unless a back-stop earthquake-style national scheme was developed.

The east and north of both main islands were predicted to dry out, while the West Coast of the South Island could expect more rain, Renwick said.

Crops and land use would have to change. Agriculture in Canterbury, Marlborough and the North Island's eastern areas might have to move to less intensive dry-land farming. The future of widespread intensive dairy farming might be limited.

Agricultural irrigation "is just going to come under more stress as eastern regions dry out.

"There will be greater competition for water resources.

"Any tourism associated with glaciers would be gone, along with the water supplies that go with snow and ice."

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Renwick urged New Zealand to become a world leader in the move to carbon neutrality - not emitting more carbon than is absorbed - by means such as converting to 100 per cent renewable energy sources and switching to electric vehicles.

A carbon-neutral New Zealand could join like-minded countries to move the rest of the world to reach the goal.