DOI: 10.5281/zenodo.15264564
title: Sea-Level Rise Visualizations Based on Projection Data from the NOAA 2017 Report

description: This Geographic Information System (GIS) dataset is part of a comprehensive effort designed to facilitate analysis and understanding of sea-level-rise exposure in the United States and outlying territories. The dataset is derived from sea-level-rise projections published in two National Oceanic and Atmospheric Administration (NOAA) technical reports: 1) Global and Regional Sea Level Rise Scenarios for the United States (2017; https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_and_Regional_SLR_Scenarios_for_the_US_final.pdf) and 2) Global and Regional Sea Level Rise Scenarios for the United States: Updated Mean projections and Extreme Water Level Probabilities Along U.S. Coastlines (2022; https://sealevel.globalchange.gov/internal_resources/756/noaa-nos-techrpt01-global-regional-SLR-scenarios-US.pdf).

Each of the NOAA technical reports includes multiple sets of point projections based on mean global sea-level-rise scenarios. Global mean sea-level-rise scenarios provide an overall estimate of how sea level could change in the future. However, local effects can produce sea level changes that are substantially different than the global average. To capture those effects, the sea-level-rise projections produced for these reports utilized a 1-degree grid (approximately 111 km by 89 km at 38° north latitude) covering the coastlines of the U.S. mainland, Alaska, Hawaii, and the Caribbean and Pacific Island territories as well as the precise location of tide gauges along these coastlines. Adjustments to sea level projections at each point location include 1) shifts in oceanographic factors such as circulation patterns, 2) changes in the Earth’s gravitational field and rotation, and flexure of the crust and upper mantle, due to melting of land-based ice, 3) vertical land movement (subsidence or uplift) due to glacial isostatic adjustment (ongoing changes in elevation due to the retreat of ice sheets at the end of the last Ice Age), sediment compaction, groundwater and fossil fuel withdrawals and other non-climatic factors.

The 2017 report included six scenarios: 0.3, 0.5, 1.0, 1.5, 2.0 and 2.5 meters of global mean sea-level rise; the 2022 report reassessed the projections for the first five scenarios and eliminated the extreme (2.5-m) scenario from consideration based on its very low probability of occurrence. The projections in these reports are provided at approximately decadal time scales and include a year 2000 baseline and the following time horizons: 2010 (2017 dataset only), 2020, 2030, 2040, 2050, 2060, 2070, 2080, 2090, 2100, 2110 (2022 dataset only), 2120, 2130 (2022 dataset only), 2140 (2022 dataset only), 2150, and 2200 (2017 dataset only). GIS visualizations for each of these 149 combinations is available as polygons that show areal extent of mean sea level and rasters that include a water depth component for each pixel at 30-m resolution. Data files are grouped by dataset (2017 or 2022) and geography, with the continental United States divided along regional boundaries used by the US Environmental protection Agency.

These datasets are intended to provide users with GIS data layers linked to time horizons that are useful to programmatic or project-based planning processes, thus providing critical insight for policymakers, researchers, planners, and others concerned with climate adaptation practices addressing sea-level rise in coastal areas.