Abstract: | ABSTRACT: In situ and remote sensing techniques for measuring thermal plumes are compared for data taken at the Point Beach Nuclear Power Plant on Lake Michigan for five separate occasions. The in situ method employed a boat whose position was determined with a microwave ranging system. Temperatures at the surface and at various depths were measured with fast response thermistor probes. The remote sensing technique utilized an infrared scanner in the 8 to 14 micron range. Comparison of the plumes indicates good agreement with respect to plume configurations, areas within isotherms and centerline temperature decays for all except one occasion, a calm day characterized by no waves, low wind and ambient current velocities. Robable reasons for disagreement under such ambient conditions are discussed. The inherent advantages and disadvantages of each method are discussed in light of the results of the five sets of data. This includes both the data collecting and data analyzing procedures. It is concluded that judicious combination of both methods offers a better picture of thermal plumes than can be obtained by either technique alone. |