FY 1993

Method for extracting tidal and inertial motion from ARGOS ice buoys applied to the Barents Sea during CEAREX

Turet, P., C.H. Pease, R.S. Pritchard, and J.E. Overland

NOAA Tech. Memo. ERL PMEL-99, NTIS: PB93-190213, 63 pp (1993)

A harmonic analysis of tidal and inertial motion was applied to observations of position of ARGOS buoys deployed on drifting multiyear sea ice in the Eastern Arctic-Barents Sea during CEAREX (1988-89). We developed an ARGOS positioning-data screening protocol and constructed a constrained least squares algorithm for separate estimation of tidal and inertial currents. This analysis provided estimates of individual tidal components at 15-day intervals along the sea ice buoy drift tracks. This technique shows a reasonable qualitative distinction in current components at nearby semi-diurnal frequencies. Estimates of errors due to sampling and collinearity are derived directly from model statistics. Estimates of velocity produced from the unequally time-based data are then used for interpolation to a regular time grid for spectral analysis. Computed velocities (up to 70 cm s for M tidal motion over Spitsbergen Bank southeast of Svalbard) are in close agreement with the regional tidal model of Gjevik et al. (1990, 1993).