TASITA—Towed Air–Sea interface Temperature Analyzer

Abstract

An accurate platinum RTD-based (resistive temperature device) system has been developed to measure the vertical temperature profile in the region of the atmosphere-ocean interface. TASITA, the towed air?sea interaction temperature analyzer, continuously measures the vertical temperature profile using 17 fixed temperature probes mounted on the instrument: 9 in the uppermost meter of the ocean, and 8 in the lowest 2 m of the atmosphere. The absolute accuracy is better than ±0.05°C, and the relative accuracy between RTDs is ±0.01°C. The instrument is designed to be towed beside a research vessel in undisturbed water outside the ship's wake. Towing speeds between 4 and 8 kt are possible. Instrument operational use is aimed specifically at low wind conditions when the sea surface is smooth to slight and mixing in the top few meters of the ocean is inhibited. Under these conditions a diurnal warm surface water layer is often present in which the surface temperature of the water is markedly different to that tens of centimeters below. Data collected in the western equatorial Pacific show variations in the temperature structure of the surface mixed layer caused by solar beating of the ocean surface and freshwater lenses resulting from heavy precipitation.