Insuring property under climate change

Climate change will increasingly create severe risks for New Zealand’s coastal housing stock. Even a small amount of sea level rise will substantially exacerbate the costs of flooding and storm surges (Parliamentary Commissioner for the Environment, 2015). Under the Intergovernmental Panel on Climate Change’s (IPCC) three mitigation scenarios, global average sea levels are likely to rise by between 28cm and 73cm by 2100 (above the 1986–2005 average). Under the IPCC’s high emissions scenario the sea level is likely to rise by between 52cm and 98cm by 2100 (IPCC, 2013). Only collapse of parts of the Antarctic ice sheet, if triggered, could cause the sea level to rise substantially above these ranges. Some regions in New Zealand (including the main urban centres) have high enough quality geographic data to infer the number of homes at risk. In those regions, there are over 43,000 homes within 1.5m of the present average spring high tide and over 8,000 within 50cm.