Arctic Oceanographic Measurements from Drifting Ice Islands. (1). Gravity Observations. (2).

Abstract

Investigations in hydroacoustics and marine geophysics were conducted from two drifting ice stations, T-3 and Arlis II, in the Arctic Ocean. Long range sound propagation experiments were made over a number of paths between ice stations and also with icebreakers. The signals from explosives are transmitted to great ranges in the Arctic surface SOFAR channel. The character of these signals is explained in principal by both ray and mode theory. Background noise is created by cracking and crushing of the ice cover. The sources and variability of the background noise are discussed. Geophysical investigations included navigation, ocean depth, gravity and magnetics. Marine geological investigations included bottom photography, nephelometry and coring. Improvement of accuracy of sea gravity measurements by consideration of the cross coupling and off leveling errors is discussed. The use of satellite navigation for increasing navigational accuracy and hence the accuracy of gravity measurements is described. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1971
Accession Number
AD0728803

Entities

People

  • Kenneth L. Hunkins
  • Manik Talwani

Organizations

  • Lamont–Doherty Earth Observatory

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Accuracy
  • Arctic Ocean
  • Background Noise
  • Geophysics
  • Marine Geophysics
  • Measurement
  • Navigation
  • Noise
  • Oceans
  • Photography

Fields of Study

  • Environmental science
  • Physics

Readers

  • Oceanography.
  • Polar and Arctic Studies
  • Radar Systems Engineering.

Technology Areas

  • Space