The National Coastal Property Model (NCPM) simulates flood damages resulting from sea level rise and storm surge along the contiguous U.S.coastline.The model also projects local-level investments in a set of adaptation measures under the assumption that these measures will be adopted when benefits exceed the costs over a 30-year period.However, it has been observed that individuals and communities often underinvest in adaptive measures relative to standard cost-benefit assumptions due to financial, psychological, sociopolitical, and technological factors.
This study applies an updated version of the NCPM to incorporate Picnic Basket improved cost-benefit tests and to approximate observed sub-optimal flood risk reduction behavior.The updated NCPM is tested for two multi-county sites: Virginia Beach, VA and Tampa, FL.Sub-optimal adaptation approaches slow the implementation of adaptation measures throughout the 100-year simulation and they increase the amount of flood damages, especially early in the simulation.The net effect is an increase in total present value cost of $1.1 to $1.
3 billion (2015 USD), representing about a 10% increase compared to optimal adaptation approaches.Future calibrations against historical data and incorporation of non-economic factors driving adaptation decisions could prove useful in better understanding ACAI the impacts of continued sub-optimal behavior.