The third was taken on April 8th. The two buildings seen in the foreground of the third image are also seen in the second. Click on an image for a larger version. The SeaWiFS images are true color since they have several bands in the visible spectrum, hence we are able to see the dust as brownish areas over the ocean, even in the cloudy regions. This cannot be done with conventional satellite imagery which provide only one visible band.
Optical depth is a simple measure of the amount of aerosol in a column.
ScienceNewsOnline Story About Dust Events Back to Top 6.