Alaska Region Digital Elevation Model


Release notification: ARDEM version 2.0 (December 2013) is now available. Check back at this site for periodic updates or email us to be placed on the notification list for future improvements.

We have created a bathymetric digital elevation model (DEM) with nominal 1-km grid spacing over the domain 45ºN-80ºN and 130ºE-120ºW. With the exception of a portion of the outer Siberian shelves, the DEM is based solely on ship sounding datapoints, including Electronic Navigation Chart (ENC) point soundings, research vessel underway soundings, multibeam swath mapping datasets and digitized point soundings from paper nautical charts. Please note that in some regions the 1-km coverage is resolved and in many regions 1 km is not resolved.

Use and copyright: This DEM is freely available and distributable but may not be repackaged for commercial purposes. USE THIS DEM AT YOUR OWN RISK. This product is not for navigational purposes. This is a research-grade product in development and we expect that there are regions that do not well reflect actual bathymetry and topography. See the Land Elevations and Citations sections below for additional use and copyright information.

Land Elevations: In order to assist those who have interest in employing a combined bathymetric-topographic DEM, we have spliced the ocean DEM grid with land elevations from the Global Land One-kilometer Base Elevation (GLOBE) 1-km open source DEM. Because the GLOBE DEM is based on a pixel registration grid, we have employed a bilinear interpolation to re-register to gridline nodes. Please see the GLOBE web site for detailed documentation, use policies and copyright information. The GLOBE DEM use citation is listed below.

Bathymetry in the Arctic: The ARDEMv2.0 grid employs depths from the International Bathymetric Chart of the Arctic Ocean (IBCAO) for the region within the polygon bounded by the following points: 130ºE/76.8ºN, 154ºE/76.8ºN, 154ºE/74ºN, 172ºE/74ºN, 172ºE/72ºN, 186ºE/72ºN, 186ºE/71.5ºN, 198ºE/71.5ºN, 198ºE/68ºN, 240ºE/68ºN, 240ºE/80ºN, 130ºE/80ºN. This region encompasses the northern Chukchi Sea, the Beaufort Sea, and the northern East Siberian Sea. See the IBCAO reference information below.

Grid Details: Data is gridded to a regular 30 second latitude by 60 second longitude grid (nominally ~ 1 km), with gridline node registration. Software to to read, reproject, subsample and plot this dataset is freely available at the Generic Mapping Tools (GMT) website.

Download the DEM: Via GMT NetCDF compatible file.

Feedback: We would like to hear about uses that you apply this dataset to: this information will help us secure funding for future improvements. Valuable feedback includes both success stories and identified problems with the grid.

Acknowledgements: We gratefully acknowledge the numerous organizations and individuals who have helped us assemble this expansive soundings dataset, including: National Oceanic and Atmospheric Administration (NOAA), the Canadian Hydrographic Service (CHS), NOAA's National Ocean Service (NOS) and their Hydrographic Survey Trackline Database, the National Geophysical Data Center (NGDC) and the creators of the GLOBE land elevations DEM, the Smith-Sandwell v14.1 DEM that elegantly includes ship sounding datapoints, the principal investigators on board research vessels who have made their data available to us, the Hawaii Mapping Research Group, the University of New Hampshire Center for Coastal and Ocean Mapping, the Lamont-Doherty Marine Geoscience Data System, Martin Jakobsson and the IBCAO grid, and the many individuals who have pointed us to additional data and supported our data assembly efforts. We thank the developers of the GMT toolkit for their software package that enables us to efficiently assemble this grid. Funding for this project was provided by the North Pacific Research Board (NPRB) and the Oil Spill Research Institute (OSRI).


ARDEM Contact Information: Seth Danielson