Coastal Restoration Trust of New Zealand

Coastal Dune Ecosystem Reference Database

Insurance retreat in residential properties from future sea level rise in Aotearoa New Zealand

Author
Storey, B., Owen, S., Zammit, C., &; Noy, I.
Year
2024
Journal / Source
Climatic Change
Volume
177
Number
44
Pages
21 pp
Keywords
Climate change insurance, insurability
Summary
How will the increased frequency of coastal inundation events induced by sea level rise impact residential insurance premiums, and when would insurance contracts be withdrawn? We model the contribution of localised sea level rise to the increased frequency of coastal inundation events. Examining four Aotearoa New Zealand cities, we combine historical tide-gauge extremes with geo-located property data to estimate the annual expected loss from this hazard, for each property, in order to establish when insurance retreat is likely to occur. We fnd that as sea level rise changes the frequency of inundation events, 99% of properties currently within 1% AEP coastal inundation zones can expect at least partial insurance retreat within a decade (with less than 10 cm of sea level rise). Our modelling predicts that full insurance retreat is likely within 20–25 years, with timing dependent on the property’s elevation and distance from the coast, and less intuitively, on the tidal range in each location.