ETOPO 2022: An Updated NOAA Global Relief Model

The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) develops digital elevation models (DEMs) to support the modeling of tsunami and storm surge inundation. Accurate, integrated bathymetric-topographic DEMs are essential because the shape and depth of the ocean floor affects the speed and height of waves, and the coastal land topography primarily determines the inland extent of inundation. NCEI DEMs have spatial coverages that range from the global to the local scale and, collectively, these elevation models are essential to determining the timing and extent of coastal inundation and improving community preparedness, event forecasting, and warning systems. ETOPO1, NOAA NCEIs current global relief model that seamlessly integrates topographic and bathymetric data at 1 arc-minute spatial resolution, has been an important dataset in the tsunami modeling community over the past decade. Here we present a pre-release version of ETOPO 2022, an updated global relief model with an enhanced 15 arc-second resolution, that incorporates recent advances in data sources and processing techniques since the ETOPO1 release in 2010. The ETOPO 2022 model uses a combination of numerous airborne lidar, satellite-derived topography, and shipborne bathymetry datasets from U.S. national and global sources. We employ state-of-the-art computational methods, including machine learning, to identify and correct data errors such as seams caused by the stitching of disparate data sources, point-artifacts caused by instrument and post-processing errors, and elevation biases caused by dense vegetation and urban structures in digital surface models to improve relative and absolute horizontal geolocation and vertical accuracies of the ETOPO global relief model. We also use widescale bare-earth topographic data from NASAs ICESat-2 and other vetted data sources to independently validate both the input datasets and the final ETOPO 2022 model. An initial release of the full ETOPO 2022 model is planned for September 2022, with periodic model update releases at potentially higher-resolutions to follow.