Ocean color results for MODIS Aqua:

Collection 6 evaluation

Gerhard Meistera,b

a: Futuretech Corp.

b: OBPG (Ocean Biology Processing Group)

11/25/09

MsWG, 12/02/09

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Overview

• Two types of test: temporal trend (AT for Aqua, ST for SeaWiFS) and scan angle dependence (AV for Aqua)

• Three LUTs will be compared: operational (V5.0.37.1b for coll. 6 code, AT42, AV09), standard collection 6 (V6.1.5.0, AT44, AV10) and ALT (V6.1.5.0_ALT, AT45, AV11)

• AT44 shows improvement for band 14 (important for FLH), band 8 got worse

• AV10 improves scan angle dependency for 547 at the end of the mission, but worse for 443 at the end

• AT45 shows improvement at the end, but overall downward trend remains unchanged

• Only a few selected plots will be shown here, all plots are available at oceancolor.gsfc.nasa.gov/ANALYSIS/global/

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Trends of chlor-a in olig. water:

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Trends of Rrs 547nm in olig. water:

5

Trends of Rrs 443nm in olig. water:

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Trends of Rrs 412nm in olig. water:

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Trends of FLH bands (13 and 14):

8

RVS for nLw 547nm (op.):

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RVS for nLw 547nm (coll. 6):

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RVS for nLw 443nm (op. and coll.6):

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RVS for nLw 412nm (op. and coll. 6):

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RVS for nLw 412nm (coll. 6 and ALT):

13

RVS for AOT (op. and coll. 6):

14

RVS for Angstrom (op. and coll. 6):

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Summary

• Collection 6 LUT improves temporal trends for longer wavelengths (500-700nm); significant improvement for FLH

• Collection 6 standard LUT increases trend seen for 412nm Rrs, ALT version provides only small improvement at the end of mission for temporal trend, significant improvement for RVS at end of mission

• Striping is generally worse for collection 6 LUTs• Path forward: MCST will deliver collection 6 LUTs with

detector trends using collection 5 methodology, OBPG will vicariously calibrate band 8 using SeaWiFS