i Detection of Smoke and Dust Aerosols Using Multi-sensor Satellite ...

all pixels over both land and ocean. The threshold values of BTD (3.7, 12) are 15 K over
land and 9 K over ocean. The total errors for land and ocean branches are estimated. It is
worth noting that the total error is not equal to the summation of errors from each test
because the overlap exists among some index tests. The accuracy of algorithm over land
is much higher than that over ocean. The large errors over ocean are mainly attributed to
the undetected thin smoke pixels. In fact, it is very difficult to detect those smoke pixels
whose magnitude is relatively low. The smoke plume usually originates from fires in land
areas and the plume magnitude becomes weaker and weaker during the motion from land
to ocean. Therefore, the probable reason is that there are much more thin smoke pixels
over ocean than over land to reduce the algorithm precision.
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