Estimation of Estimation of in situin situ UV UV penetrationpenetration

GOAL: use a global database of measured Kd(UV) and Rrs() coupled with GSM01 retrievals to

develop a model for in situ Kd(UV)

Modeling results as of 7-17-2004 (DV)

The model itself...

GSM01

Measured Rrs() (5 SeaWiFS )

Modeled: acdm(443), [chl], bbp(443)

Kmodel() = Kw() + CCexp(-S(-443)) +

aph*GSM01_chl + GSM01_bbp(/443)-1

Kw from Morel & Maritorena (2001) (Kw(320)= 0.0340; Kw(340) = 0.0281; Kw(380)=0.0161; Kw(412) = 0.0079)

CC w0*GSM01_acdm + w1*GSM01_acdm2

S S0 + S1*(GSM01_acdm + GSM01_acdm2)

** solve for w0 w1 S0 S1 aph* using global Kd

data set **

Restricted data set (chla < 1.5 mg / m3)

PROJECT n < 1.5 % of originalPnB 109 66.1EPIC 112 100CDOM 7 100Sulfur 18 100BBOP 87 100ACE Asia 36 92.3AMLR 56 96.6CalCOFI 159 90.8Indoex 14 100JGOFS 37 77.1Japan Sea 26 100

The overall model fit chla < 1.5:

The overall model fit (all data):

Large bias marked with an ‘x’

By wavelength:

Example, 340 nm:

Example, 380 nm:

The retrieved parameters:

S0 = 0.0133 / S1 = -0.0598 / w0 = 2.2158 / w1 = -3.9872 / aph

* = 0.009145

Relative contribution by term