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