OPUS Use in Alaska: A Favored Positioning Tool from the North Slope to the Remote Aleutian Islands

Abstract

Since 2002, the National Geodetic Survey (NGS) has made available to the general engineering and surveying community a web-based GPS processing software named the Online Positioning User Service (OPUS). The popularity of this free service has steadily increased over time and Alaskan GPS users were no exception in quickly adopting this simple-to-use positioning tool. This article discusses recent CORS improvements performed in Alaska and the importance of keeping track of changing NGS published coordinates which is crucial to all GPS surveys in a region with crustal dynamics as active as Alaska. The status of the Continuously Operating Reference Stations (CORS) network in Alaska will also be reviewed. More CORS sites in the state will undoubtedly help the use of other newly developed versions of OPUS, such as OPUS-RS, OPUS-Net and OPUS-Projects. Each one of these flavors contains its own specific applications; therefore, they expand the OPUS arsenal with a variety of alternatives making the culmination of surveying engineering and mapping projects more user friendly.