Chuanmin Hu , Lian Feng , Zhongping Lee University of South … · 2016-07-29 · Chuanmin Hu1,...

ChuanminHu1,LianFeng1,ZhongpingLee2

1UniversityofSouthFlorida2UniversityofMassachuse@sBoston

FundingprovidedbyNASAOBBprogram

MODIS/VIIRSScienceTeammeeLng,6–10June2016,SilverSpring,MD

MODISandGOEScloud-freeprobability(Fengetal.,submi@ed)

DailypercentagevaliddatafromAquaandTerra2003–2014(FengandHu,2016a)

Chl

nFLHSST

GlobalcompositedataisalwaysatradebetweenqualityandquanLty

Relax Chl flag around cloud edges? ChlOcx ChlOCI

ME-freedirecLon(FengandHu,2016b)

SeaWiFS

ME-freeandME-containingdirecLons(FengandHu,2016b)

The SeaDAS operational masking window (7x5) could be changed to 3x3 with the OCI Chl-a algorithm, without losing confidence for the remaining data

?

Unfortunately, of the entire global data and SeaBASS archive, we could not find any field measurement just in the “recovered” pixels for validation

RrserrorsareNOTspectrallyindependent(Huetal.,2013)

Neural-netQAArelaLvelyimmunetoinputRrserrors,thereforecanbeusedtoderiveIOPsand“corrected”Rrssimultaneously(Chenetal.,2016,JGR).Theschemeisappliedtoallnon-zeroRrspixels

SeaWiFSRrs670overNAtlanLcon2/20/1998,originalandrecovered

  OCIisnearlyimmunetoperturbaLonsincludingcloudadjacency

  7x5straylightflagmayberelaxedto3x3forlow-Chlwaterswithoutlosingquality

  Theresultwillbe>40%validdatavolumeforlow-Chlwaters

  ThedifficultyoflackoffieldvalidaLonfromthe“recovered”pixelsmaybecircumventedfromglobalstaLsLcs

  Howtoimplementforlow-Chlwatersonly?