NZ SeaRise Project
Scientists agree that, as a consequence of global warming, the oceans are rising and will continue to do so for centuries to come.
But there is uncertainty around how much the sea will rise, how rapidly it will rise, and how it will impact New Zealand’s coastal areas. The Antarctic Research Centre is host to The NZ SeaRise project, a $7.1 million, five-year (2018-2023) research programme funded by the Ministry of Business, Innovation and Employment.
The two main contributors to global sea-level rise are thermal expansion of the oceans and melting of polar ice sheets. The NZ SeaRise programme addresses knowledge gaps that are hampering our ability to anticipate and manage the impacts and risks of future sea-level rise because of: (1) the uncertain contribution of the polar ice sheets to global and regional projections; and (2) a lack of understanding of the influence of vertical land movements and changes in sea-surface height in local predictions.
Included in research findings to date is new data combining where land is sinking with the latest international sea-level rise projections. New Zealand’s two largest cities - Auckland and Wellington - risk inundation decades earlier than expected. Some areas in these cities are sinking 3mm or 4mm a year - about the annual rate at which the sea is rising. In just 18 years parts of the capital will see 30cm of sea-level rise, causing once-in-a-century flood damage every year. Many parts of Auckland will see the sea-level rise 30-50% faster than what was previously thought. Previously, councils and other authorities had not expected to reach this threshold until 2060 - halving the time to plan for mitigation or retreat.
Globally, sea levels are expected to rise about half a metre by 2100 - but for large parts of New Zealand it could more than double that because of land subsidence.
Find out more about the NZ SeaRise project here.