NOAA NOS Manual: Accurate elevations for sea level change sentinel sites

This document provides guidelines for coastal reserves, parks, refuges, and other coastal habitat management areas to be identified as long-term “sea level change sentinel sites,” monitoring both the changes in local water levels as well as the resulting impacts on the adjacent coastal ecosystem. The term “sea level change sentinel site” has been defined differently by various agencies and organizations, but this document assumes any strategy to monitor climate change impacts related to water level changes must include three basic components described below. 1. Local, high accuracy vertical control network connected to a consistent reference frame (i.e., the National Spatial Reference System (NSRS)), with maintained high accuracy connections among all other components of the sentinel site; 2. Long-term high accuracy water level sensor(s) with verified vertical stability and high frequency data capture (e.g., 6-minute data); 3. Long-term coastal habitat monitoring infrastructure (e.g. Surface Elevation Tables (SETs); groundwater wells, permanent vegetation transects or monitoring plots, etc.).