Remote Sensing of SST Around the Outfall of a Power Plant from
LANDSAT and NOAA Satellites
Data processing Procedures
Two methods were applied to the TM data for coastal thermal plume analysis. The first method is to calculate the corrected radiance and temperature by putting radiosonda data into-LOWTRAN 7 to correct for atmospheric effects. The shoreline can be determined from the band5 digital data, because the reflectance of solar energy in the near-IR band from the water surface is much lower than from the land surface. Fig.2 shows the shoreline determination of the studied site using contour lines of band 5 digital counts of 20. Note that an area of the size 70 x 70 pixels was selected for data analysis in this study. The Hsinta harbor, power plant and the outfall can all be clearly identified in Fig. 2 The second method incorporates AVHRR data into TM temperature of each pixel near thermalplume deviates markedly from the ground truth due to the atmospheric effect, they still exhibit a correct spatial distribution of temperature. The spatial distribution characteristics of temperature can be represented by a simple dimensionless matrix P(i), i.e.,
Where T
b(i)is the uncorrected brightness temperature of the ith pixel,
b is the average of brightness temperature of all pixels in the selected area. Since the AVHRR-derived SST has been thermal plume can be obtained by
T(i) = P(i) x 2)
Where
is the average of AVHRR-derived SST of All pixels in the selected area, T(i) is the corrected SST of the ith pixel.
Fig.2 Shoreline determination using Landsat-5 TM band 5. Solid lines indicate contour lines of digital counts with value of 20.
