Datum Adequacy for Assessing Ownership of Alaska's Coastal and Marine Resources: A Coast Surveyors' Perspective

Abstract

"Alaska comprises approximately 33,000 miles of the United States coastline, 900,000 square miles of the US EEZ, and offers 55% of the US Long Term Potential Yield of fishery resources. Alaska also offers extensive oil and gas reserves and mineral deposits that either lie adjacent to navigable waters or require access to navigable waters to be commercially viable. Yet, the majority of Alaska remains poorly mapped to common horizontal and vertical datum, presenting challenges to stakeholders in the effort for sustaining local communities through resource development, conservation of the species under fisheries management plans, and preservation of lifestyles. This paper will define the terms of reference for horizontal and vertical datum and identify the history and adequacy of datums in Alaska as depicted in federal cartographic products and developed through federal programs. Limitations in distribution and duration of observations will be noted with regards to past and present survey efforts. Reference to ongoing geological processes, including erosion and accretion, crustal motion and plate tectonics, and significant seismic events will be noted as key factors limiting the value of historical measurements. More robust natural processes, particularly storm surge, slumping and glacial rebound, and thawing of permafrost, glaciers, and icecaps are accelerating the datum change. With improving technologies, including GPS, the changes are being documented. Yet, as documented, the question of adequacy and accuracy of existing datum, and their associated cartographic products, needs to be considered. The specific challenges with the 'Dinkum Sands' decision will be reviewed along with comments on the datum challenges for determining the offshore boundary of Arctic National Wildlife Refuge, National Petroleum Reserve, Alaska, and other federal lands in western Alaska. A final perspective will be offered on the challenges of defining new boundaries under changing laws, including Article 76 of the United Nations Convention on the Law of the Seas."