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The Advanced Very High Resolution Radiometer (AVHRR) instrument aboard the NOAA series of polar orbiting satellites can be used to assess the extent and variability of hurricane-induced sediment concentrations within coastal waters, presented here as a satellite-derived turbidity product. This process is accomplished by using the atmospherically corrected AVHRR channel 1 sensor (visible light) to measure the percentage of reflected or upward scattering light emerging from the upper few meters of the ocean water column. This reflectance value is correlated with the concentration of sediments in the water, with higher reflectance values indicative of an increased sediment load.
The above table lists the hurricanes since 1985 that made landfall and for which a set of turbidity images are available. An "after" image refers to the period immediately following the hurricane landfall (usually within one day) while a "before" image represents the most cloud-free image available preceding landfall and is indicative of a more "typical" structure. The "difference" image represents the "after" image minus the "before" image. A set of "before", "after", and "difference" sea surface temperature images are available as well.
For all images, land is depicted as gray, clouds are masked to white, and areas of no data are black. The hurricane ground track has also been overlaid onto each image. A software-enhanced perspective view of each hurricane derived from the AVHRR satellite data is shown at the top of each page.
Within each hurricane page a Java based image viewer is also available for simultaneous browsing of the turbidity or SST image sets. This applet has been successfully tested with Netscape 3.01 and 4.03. At least a Pentium class computer and 32 MB of RAM are necessary for the applet to run smoothly.