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ration of level 2 and level 3 products. Because the stripe noise does not affect similarly
all spectral bands, the derivation of geophysical variables often results in a stripe noise
amplification. For instance, striping can hardly be seen on bands 31 and 32. Yet, SWIR
and LWIR SST products display stripe noise. MODIS SST is obtained with an NLSST
(Non linear SST) algorithm that can be expressed as :
SST = a 0 + a 1 .BT 11 + a 2 .(BT 11 − BT 12 )+a 3 .(BT 11 − BT 12 ).( 1 − 1) (2.10)
µ
where a 0 , a 1 , a 2 , a 3 are time dependent coefficients determined by the Rosentiel School of
Marine and Atmospheric Science from in-situ measurements. BT 11 and BT 12 are brightness
temperatures of bands 31 and 32, and µ is the cosine of the sensor zenith angle. The
difference between bands 31 and 32 is used to correct atmospheric effects due to waper
vapor absorption and is responsible for the introduction of striping in the SST. The amplification
of striping can be stronger on products generated from algorithms that include
multiplicative operations between spectral bands, which is the case of many bio-optical
models used to estimate oceanographic variables.