Evaluating knowledge gaps in sea-level rise assessments from the United States

There have been many scientific advances regarding future sea-level projections, however it is unclear if these have been transferred to assessment reports used by stakeholders. Here, we present a first-of-its-kind comprehensive analysis of regional sea-level rise (SLR) assessments for the United States (U.S.). We identify variations in time horizons over which regions plan for SLR, with 25 projections from the U.S. Northeast and West that extend to 2150 or beyond, but no projections from the U.S. South beyond 2100. The majority of 2100 projections from the U.S. Northeast (77%) and West (83%) include ranges of future SLR, while 88% of projections from the U.S. South include only single estimates. At least 56% of U.S. communities in the database underestimate the upper end of future SLR compared to the regional projections of the Intergovernmental Panel on Climate Change Sixth Assessment Report.Ministry of Education (MOE)National Environmental Agency (NEA)National Research Foundation (NRF)Published versionThis work was supported by funding from the National Science Foundation awarded to AJG (EAR-1625150). BPH, FT, and CT are supported by the Singapore Ministry of Education Academic Research Fund MOE2019-T3-1-004, the National Research Foundation Singapore, and the Singapore Ministry of Education, under the Research Centers of Excellence initiative and the National Sea Level Program Funding Initiative (Award USS-IF-2020-1), administered by the National Environment Agency, Singapore and supported by the National Research Foundation, Singapore. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the author(s) and do not reflect the views of the N.R.F., M.N.D., and N.E.A. This work is Earth Observatory of Singapore contribution 487. We thank the IPCC AR6 SLR projection authors for developing and making the sea-level rise projections available, multiple funding agencies for supporting the development of the IPCC AR6 SLR projections, and the NASA Sea Level Change Team for developing and hosting the IPCC AR6 Sea Level Projection tool