Climate change is taking its toll as the sea keeps crawling onto New Zealand's sinking coastline, halving the time authorities thought they had to take action, according to an NZ SeaRise study released earlier this week.
The document determined that parts of Wellington, the capital, will see 30 centimeters of sea level rise in just 18 years, which would turn rare floods into annual events when they used to be once-in-a-century episodes.
According to scientific projections, homes and other buildings in Auckland, Wellington, and elsewhere risk being inundated decades earlier than expected as sea levels are rising twice as fast as previously thought in many parts of the country. Authorities in New Zealand had not expected levels to reach this threshold until 2060.
NZ SeaRise is a five-year government-funded research program that combines data on sinking land with up-to-date international sea-level rise projections. Involving some 30 local and international experts, it takes into account the natural rises and falls of the country’s coastline, as well as climate change and warming temperatures.
A global sea-level rise of 25-30 cm by 2060 is unavoidable regardless of future emissions. But in many of NZ’s most populated regions vertical land movements mean these changes may happen 20 to 30 years sooner than previously expected.
Existing global emissions policies show sea levels are expected to rise about 0.6 meters by the year 2100. However, for large parts of New Zealand, this would double to about 1.2 meters, says NZ SeaRise co-leader Tim Naish, of the Victoria University of Wellington. ”We have less time to act than we thought,” he said.
Some areas in Auckland and Wellington are sinking 3-4 millimeters a year, which corresponds with the annual rate at which the sea is rising.
New Zealand authorities are expected to adopt new measures in light of the new information that has been made public.
To begin with, natural hazards and planning experts have said councils should be held accountable for allowing buildings in risky coastal areas.