This turbidity distribution map is developed by statistical method using
a regression analysis between the field data of Bureau of Environment,TMG and
ASTER VNIR (band 1,2) data.
The algorithm of turbidity using ASTER data is expressed below.
D = function (L1,L2)
(L1,L2 : radiance at band 1 and band 2)
The two regression equations used this time are below.
(equation 1) : D = 12.040 * (L2 / L1)
(eauation 2) : D = 1.613 * {(L1 + L2) / (L1 - L2)}
Although the outcome of two equations are different quantitatively,
they are consistent qualitatively in terms of the high value at Edogawa, estuary of Arakawa, Tamagawa and so on.
(Caution:the ranges of the graphs are different)
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