Rising sea levels will make it riskier to live in New Zealand and render parts of the coast uninhabitable over the next century, a climate scientist says in the wake of an international report.
The Intergovernmental Panel on Climate Change (IPCC) report has underscored New Zealand's vulnerability as an island in the Pacific, finding that rising greenhouse gases will contribute towards more extreme weather events like storms, floods and droughts in the 21st century.
Scientists said in the report it was "virtually certain" there would be more hot days than cold days in the future, with more warm temperature extremes worldwide.
The frequency and intensity of heatwaves and droughts was set to increase. It was also very likely that rising sea levels would contribute to upward trends in "extreme coastal high water levels" in the future.
For New Zealand, where 12 of the country's 15 largest cities are located on the coast, the impact could not be ignored, Niwa (National Institute for Water and Atmospheric Research) principal climate scientist Dr James Renwick said.
"Climate change means a riskier future in terms of extreme weather events.
"So it depends on what level of risk we are prepared to take, and how much we are going to do to prepare for that risk.
"We will be working through, with the Government, the impacts of this for New Zealand and how it is approached from a policy point of view."
In the not-too-distant future, roads and houses would have to be moved, and sea-walls and stormwater drains built to cope with the sea level rises, he said.
Cities like Wellington and Auckland with their proximity to harbours, would be increasingly susceptible to flooding in storms and at high tide.
And for a lot of the low-lying Pacific Islands, it would be "devastating", Dr Renwick said.
"If we want to rein all this in before it gets too overwhelming, then reducing greenhouse gases is the way to go and there really needs to be global political action to see this happen."
The scientists also warned that extreme weather events would have increasing economic impacts on industries reliant on the climate – which in New Zealand would include agriculture, horticulture and energy.
It took a team of 80 scientists from around the world more than three years to assemble the report, which was written after the analysis of thousands of pages of literature based on observations since the 1950s.
The report is intended to act as a guide for policymakers in governments worldwide.
- Fairfax Media