Demonstration projects were sought that would address two objectives: (1) update the time series based information underlying relevant data components in the Defense Regional Sea Level (DRSL) databases and (2) provide recently acquired, scenario-based sea-level change data for Department of Defense (DoD) worldwide sites that were added by the 2019 changes to the DoD’s Real Property Assets Database.

Proposed projects were asked to assess the following:

• Extend the time-series records of the DRSL data sources (i.e., tide gauge and global positioning system [GPS]) used to inform estimates of vertical land movement (VLM) for all sites in the DRSL database for which these types of data are available and usable for VLM estimates.
• Update the algorithms used in the original DRSL database to determine which data set to use (tide gauge, GPS, or glacial isostatic adjustment [GIA]) to justify either maintaining the existing or establishing a new recommended VLM rate for each individual DRSL site based on proximity of the data source and its representativeness to the site under consideration (note that GIA data are broad-scale gridded data) and confidence in the quality of the source data.
• For all sites worldwide in the DRSL database that are associated with either site specific tide-gauge information or for which a regional frequency analysis (RFA) using multiple tide gauges in a region can be determined to provide credible estimates of extreme (still) water levels, update or provide initial estimates of EWLs for each applicable DRSL scenario. When both single tide gauge and an RFA analysis are available, provide both scenario-based estimates.
• For the time-series dependent data above, for each of their uses, provide a defensible basis for the appropriate frequency at which changes in the time-series record information should be assessed to determine whether updates to DRSL database information may be needed.

Proposed projects should have demonstrated familiarity with the methods and scenarios used to construct the original DRSL database.¹ All DRSL sites occur within a 20-km buffer zone from the coast or were otherwise determined to occur within 20 km of a tidally influenced area. Performers would be working with a replicate test version of the database to enable development and testing activities to occur without disrupting operational use.

¹ See Hall, J.A., S. Gill, J. Obeysekera, W. Sweet, K. Knuuti, and J. Marburger. 2016. Regional sea level scenarios for coastal risk management: Managing the uncertainty of future sea level change and extreme water levels for Department of Defense coastal sites worldwide. Alexandria, Virginia: Department of Defense, Strategic Environmental Research and Development Program.

Funded projects will appear below as project overviews are posted to the website.

Given the dynamic nature of the physical processes involved, the underlying data lose accuracy over time; enhancing the quality of the data sources and record lengths used improves reliability of the data and will reduce inherent uncertainties and thereby improve the resilience of DoD coastal installations.

Sea-level change involves long-term, emission-dependent trends in global sea level, related regional effects due to the impacts of climate-forced ice melt and ocean circulation (or dynamical sea level) changes on the spatial patterns of sea level change, and non-climate related changes in coastal elevations (i.e., VLM). Layered atop these long-term trends are additional and frequency-dependent changes in water levels involving tides, storm surge, and waves. Magnitude estimates and their accuracy over time for a number of the above contributions to sea-level change have one or more of the following dependencies: data source quality and availability and record length for time-series related data (e.g., tide gauge data).