FY 1997

Temperature errors in TAO data induced by mooring motion

McCarty, M.E., L.J. Mangum, and M.J. McPhaden

NOAA Tech. Memo. ERL PMEL-108, NTIS: PB97-146492, 68 pp (1997)

Moored subsurface temperature measurements from the Tropical Atmosphere Ocean (TAO) Array are subject to errors resulting from vertical motion of the instrumented mooring line. The magnitude of the errors depends on both environmental conditions and mooring design. This report describes a method for estimating these errors using subsurface pressure data to determine vertical excursions of the mooring line. For taut-line moorings examined, typical mooring motion-induced temperature errors are largest in the upper thermocline, with root mean square (RMS) errors of 0.15°-0.45°C. Slack-line moorings typically have larger RMS errors (0.3°-1.1°C), in some cases with maxima at the lowest instrumented depth. These errors are correctable using processing procedures developed in this report.