CALIBRATION AND HELD TEST OF IRT 



by Takashi Ichiye and Noel B. Plutchak, Lamont Geological Observatory, 

 Palisades, New York 



INTRODUCTION 



Our interest in using IRT lies mostly in determining the fine structure of the surface 

 water temperature concurrently with some field experiments of dye diffusion in the upper 

 layer of the ocean. In such experiments, five to fifteen gallons of rhodamine "B" dye are 

 dumped from a small boat and for several hours a light plane is used to take aerial photo- 

 graphs of dye patches. In many cases, dye patches indicate striations with spacings of 

 furrows from several tens to hundreds of meters dimension. It is speculated that such 

 striations are caused by cellular convective currents near the surface due either to tur- 

 bulent structure of surface winds or internal waves (Ichiye, lida and Plutchak, 1964; Ichiye, 

 1964). In any case, if there are cellular currents, surface water temperature may indicate 

 alternative cold and warm bands as schematically indicated in Fig. 1. In order to determine 

 such a fine structure in the surface temperature, IRT seems to be ideal if it has enough 

 accuracy since the sensor of the IRT need not be immersed in the water and thus will not 

 disturb the temperature pattern. 



This report shows results of some preliminary experiments to determine the ac- 

 curacy and operational capacity of the instrument. These results seem to indicate that 

 there are so many factors influencii^ the readings that great precaution must be taken in 

 order to obtain accurate data. 



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Figure 1. Schematic representation of alternative cold and warm bands 

 thought to be caused by cellular convective currents 



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