MODIS Ocean Filenames, Structures, and useful metadata Kay Kilpatrick University of Miami/RSMAS

Most FAQ:Why does MODIS oceans have so many files and why is everything so BIG! 1km global resolution every day Many more products Meeting the needs of a diverse user community (pleasing all the people all the time) –Pretty pictures/quick looks ; Medium quality, low resolution –Tracking fronts and features ; all pixels, high resolution –High quality climate data; High quality, medium resolution –Modelers; high quality, various projections not maps –Algorithm developers; underlying raw values

Where to get data and more information Information locations: MODIS Oceans home page – MODIS Oceans QA Browse 36km Imagery (MQABI) – Select Terra collection 4 Useful links to documentation and related web pages – Data Ordering locations: NASA GES DAAC WHOM (NASA - Goddard DAAC) WHOM, datapool, multi parameter subsetting EOS DATA GATEWAY EDG - JPL PODAAC 4km global SST only

MODIS Ocean Products MODIS Instruments: – Terra (1030 morning), MO* – Aqua (1330 afternoon) MY* Resolution: –Spatial: Level 2 - 1km swath, ~2030km x 1354km; Level 3 - 4km, 36km, 1 deg [all products are global] –Temporal Resolution: Level minute granule; Level 3 - daily, 8 day week, monthly, yearly Other data sets: - SST matchups database - ocean color diagnostic data sites

MODIS Ocean data products There are 86 ocean parameters available in over 100 categories of MODIS Ocean data types archived by (and may be obtained from) the NASA Goddard Distributed Active Archive Center. The three basic groupings of MODIS ocean data parameters are: –ocean color –sea surface temperature –ocean primary production

Parameters 36 Ocean Color parameters 3 Sea Surface Temperature parameters 8 Primary Productivity parameters (including 2 Primary Production indices) 38 Quality Control parameters.

Processing levels Level 1 - Unprocessed top of the atmosphere radiance/reflectance –At 1-km spatial resolution –5 minute granule time resolution ; 288 granules/day Level 2 swath data –At 1-km spatial resolution –5 minute granule time resolution; color 144/day, SST 288/day Level 3 global binned or mapped data – spatial resolutions of 4.63km, 36km, or 1 degree –Time resolutions of one day, 8 days, a month or a year. –The binned; ISEAG grid –The SMI mapped; cylindrical Equidistant Projection Centered at 0,0.

Level 4 Productivity Ocean primary production data is available only as binned or mapped Level 4 (i.e. L4) data. Ocean Productivity outputs are averaged weekly or yearly. Like the L3 data, the L4 data is organized spatially as either 4km ISEAG gridded bins or as maps using a Cylindrical Equidistant Projection. The mapped data products are available in a choice of 4km, 36km, or 1 degree spatial resolutions. More than one model is used for deriving these data products and some quality statistics are available.

L2 filenames 2 night and 6 day ocean files for each 5minutes M*DCL2 - water leaving radiance products M*DCL2A - derived products group 1 M*DCL2B- derived products group 2 M*DOCQC - ocean color QC parameters M*D28L2 -SST products M*D28QC- SST QC parameters File size ~80-100MB/file –* = “Y” for AQUA or “O” for Terra

Water leaving radiance products M*DOCL2 water leaving radiance (parameters 1-12) –7 bands; nLw412,nLw443,nLw488,nLw531,nLw551,nLw667, nLw678 –Tau 865 Aerosol Optical thickness 865 –Epsilon 765/865 –Aerosol model 1 –Aerosol model 2 –Epsilon of clear water

Derived products group 1 M*DOCL2A- 13 products (parameters 13-25) –CZCS_pigmentChlorophyll-a + pheopigment (fluorometric,empirical) –Chlor_MODIS Chlorophyll-a concentration (HPLC, empirical) –Pigment_c1_total Total pigment concentration (HPLC, empirical) –Chlor_flur_ht Chlorophyll fluorescence line height –Chlor_fl_base Chlorophyll fluorescence baseline –Chlor_fluor_effic Chlorophyll fluorescence efficiency –Susp-solids-conc Total suspended matter concentration in ocean –Cocco_pigment_conc Pigment concentration in coccolithophore blooms –Cocco_conc_detached Detached coccolithophore concentration –Calcite_conc Calcite concentration –K_490 Diffuse attenuation coefficient at 490 nm –Phycoeryth_concPhycoerythrobilin concentration –Phycou_conc Phycourobilin concentration

Derived products group 2 M*DOCL2A -11 products (parameters 26-36) –chlor_a2 Chlorophyll-a concentration (SeaWiFS analog) –chlor_a3 Chlorophyll-a concentration (semianalytic) –ipar Instantaneous photosynthetically available radiation –arp Instantaneous absorbed radiation by phytoplankton for fluorescence –absorp_coef_gelb Gelbstoff absorption coefficient at 400 nm –chlor_absorb Phytoplankton absorption coefficient at 675 nm –tot_absorb_412 Total absorption coefficient at 412 nm –tot_absorp_443 Total absorption coefficient at 443 nm –tot_absorb_488 Total absorption coefficient at 488 nm –tot_absorb_531 Total absorption coefficient at 531 nm –tot_absorb_551 Total absorption coefficient at 551 nm

SST L2 products M*28L2 - 3 products (parameters 36 to 40) –SST_D1 - Sea surface temperature (daytime), 11um –SST_D2 - Do not use Sea surface temperature (daytime), 4 um –SST_N1 - Sea surface temperature (nighttime), 11um –SST_N2 -Sea surface temperature (nighttime), 4um

L2 Ocean color QC file M*DOCQC - –U_Wind m/s –V_Wind m/s –Pressure mBar –Humidity kg/m2 –Ozone dobson –Latitude degree –Longitude degree –SolarZenith angle –SolarAzimuth angle –SatelliteZenith angle –SatelliteAzimuth angle –nLw670 W/m2/um/sr –Aerosol radiance 765 W/m2/um/sr –Rayleigh radiance 443 W/m2/um/sr –Glint radiance W/m2/um/sr –Whitecap radiance W/m2/um/sr

L2 SST QC file M*D28QC –D1,N1 Channel 20 brightness temperature degrees C –D2.N2 Channel 22 brightness temperature degrees C –D3,N3 Channel 23 brightness temperature degrees C –D4,N4 Channel 31 brightness temperature degrees C –D5,N5 Channel 32 brightness temperature degrees C –D6,N6Channel 20 radiance W/m2/um/sr –D7,N7 Channel 22 radiance W/m2/um/sr –D8,N8 Channel 23 radiance W/m2/um/sr –D9,N9 Channel 31 radiance W/m2/um/sr –D10,N10 Channel 32 radiance W/m2/um/sr

L3 Binned global files Binned files M*DOC{D,W,M,Y}{prod#}.parameter M*D28{D,W,M,Y}{prod#}.parameter Only available at 4km resolution intergerized sinusoidal equal area grid (ISEAG) Only bins with data values are present; –land bins and bins with no data are not in the files –Each files is self contained with sums, weights and quality levels,and all flags –Useful if you need to do statistic or your own averaging/compositing algorithms. –File size ~640MB

L3 mapped files Various time and space resolutions Cylindrical equidistant projection All bins present, including fill values (255) for land and missing data 8 map files for each product –Mean, Count,Stdev, Common flags,Quality flags,Flag byte 1, Flag byte 2, Flag byte 3 –Files sizes : 4km =67MB, 36km=1MB,1deg=.2MB

File formats All Ocean products are in EOS HDF format Values are stored as counts Scaling information to convert from counts to real numbers is located in the file metadata for each parameter (SDS) –Scale_type –Slope –Intercept

Pixel Quality Flags Each product contains all values at all levels of quality you must filter the data for your application using the quality flag. Each pixel is associated with a quality level stored as a 2 bit value (0,1,2,3) in the “quality” SDS. –The position of the quality level within the byte is given in the metadata attributes for each parameter (“Quality_Bits”). –Example: MODCL2A: Chlor_MODIS quality is in bit position 11-12, while Chlor_Fluor_ht is in position (note: 1-based numbering convention) QL=<=3 QL=0

Quality level definitions There are four quality levels  0=good  1=questionable/suspect  2= sun glint or possible cloud contaminated  3=bad, thick cloud or other failure These levels are derived by evaluating various combinations of threshold tests common to all products and specific to individual products. Other sets of flags,known as common and product specific flags, are used to store the results of these threshold tests.

MODIS Ocean Flags, quality control, and masks Kay Kilpatrick University of Miami/RSMAS Part 2

Flags The Ocean products are designed to meet the needs of a variety of users. These flags are key to controlling the quality and coverage of the data for your application.  Quality flags  Common flags  Product specific flags

How are they stored in the files All flags are stored as data type byte Quality SDS -Quality levels are stored at 2 bits Level 3- 1 byte per file only for that product integer value of 0,1,2,3,or 255 Level 2 - maximum of 3 bytes per files, must decode the bits Common flags SDS - each test is 1 bit, Level 2&3 1 byte per file L2_flags SDS - product specific tests each test is 1 bit Level 2&3 max 3 byte per file

Example metadata ncdump -h MODOCL2.A dimensions: Number of records:Swath = 2030 ; Number of samples per record:Swath = 1354 ; variables: short nLw_412(Number of records:Swath, Number of samples per record:Swath) ; nLw_412:Long_name = "Normalized water-leaving radiance at 412 nm" ; nLw_412:Scale_type = "y= Slope * x + Intercept;" ; nLw_412:Slope = 0.001f ; nLw_412:Intercept = -5.f ; nLw_412:Name = "Radiance" ; nLw_412:Units = "W/m^2/um/sr" ; nLw_412:Quality_Bits = "1-2" ;

Common flags The common flags are tests that are the same for every product The results of these tests are stored in the “common_flag” SDS as type byte.  Bit 1 Pixel not processed  Bit 2 Atmospheric correction failed  Bit 3 Satellite Zenith angle >45  Bit 4 Solar Zenith angle >70  Bit 5 Shallow water (<5km from coast or <50m deep,or inland lake)  Bit 6 Sun glint threshold or cloud 678 homogeniety exceed  Bit 7 Invalid or missing ancillary data  Bit 8 Land (include ephemeral water)

byte common_flags (Number of records:Swath, ……. common_flags:Units = "bits" ; common_flags:f01_name = "UNPROC" ; common_flags:f02_name = "ATMCOR" ; common_flags:f03_name = "SATZ" ; common_flags:f04_name = "SOLZ" ; common_flags:f05_name = "SHALLOW" ; common_flags:f06_name = "GLINT" ; common_flags:f07_name = "SUPPDATA" ; common_flags:f08_name = "LAND" ; Common flag metadata

L2_flags radiance byte 1 of 2 (nLw_412, nLw_443, nLw_488, nLw_531, nLw_551, nLw_667, nLw_678, Tau_865, Eps_78, aer_model1, aer_model2) Product specific tests Parameters (1-12 radiance products) Map MO*.1{1:12}*.hdf L3 map bit L3 binned bit L2 MODCL2 bit Cloudy; 865 threshold1259 Bad_Lw; One or more bands missing22610 Bad_Lw; Any LwXXX <= Bad_Lw; Any band counts < Atmos_Corr; Questionable polarization correction/mirror reflectance (not currently used) Atmos_Corr; Gordon aerosol failure63014 Atmos_Corr; epsilon out of range73115 Atmos_Corr - Any LaXXX <=

L2_flags radiance byte 2 of 2 (nLw_412, nLw_443, nLw_488, nLw_531, nLw_551, nLw_667, nLw_678, Tau_865, Eps_78, aer_model1, aer_model2) Product specific tests Parameters (1-12 radiance products) MO*.2{1:12}*.hdf L3 map bit L3 binned bit L2 MODCL2 bit Atmos_Corr ; Invalid Raleigh scattering data1171 nLw550_low; Calculated nLw550 is too small2182 Cocco; Coccolithophorid radiance exceeds threshold3193 TurbidCase2; Actual_rrs555 > Turbid_rs Hi_la865; Calculated La865 is too large5215 Input Lw's for Carder's clear water epsilon band (11,13) bad lo_eps; epsilon < spare8248

L2_flags derived products group 1 byte 1 of 3 (eps_clr_water, CZCS_pigment, chlor_MODIS, pigment_c1_total, chlor_fluor_ht, chlor_fluor_base, chlor_fluor_effic, susp_solids_conc, cocco_pigmnt_conc, cocco_conc_detach, clacite_conc, K_490, phycoeryth_conc, phycou_conc) Product specific tests Parameters (13-25 radiance products) Map MO*.1{12:25}*.hdf L3 map bit L3 binned bit L2 MODCL2 bit pig_C input Lw’s (bands 9 and 12) bad125 chl_a input Lw’s (bands 9,10,11,12) bad226 pig_total input Lw’s (bands 9,10,11,12) bad327 susp_solid inout Lw’s (bands 9,10,11,12) bad428 K490 input Lw’s (bands 9 and 12) bad529 FLH/chl_modis way too high, not reasonable630 FLH/chl_modis too high, approaching limit higher uncertainty 731 FLH way too high, not a reasonable value832

L2_flags derived products group 1 byte 2 of 3 ( eps_clr_water, CZCS_pigment, chlor_MODIS, pigment_c1_total, chlor_fluor_ht, chlor_fluor_base, chlor_fluor_effic, susp_solids_conc, cocco_pigmnt_conc, cocco_conc_detach, clacite_conc, K_490, phycoeryth_conc, phycou_conc) Product specific tests Parameters (13-25 radiance products) MO*.2{13:25}*.hdf L3 map bit L3 binned bit L2 MODCL2A bit FLH_Range; approaching limit higher uncertainty117 chl_modis == -1, algorithm failed, fill value present218 ARP qual >= 2, questionable319 ARP qual == 1, higher uncertainty420 CFE too high, not reasonable value521 coccolith algorithm input Lwís (bands 9 and 12) bad622 LoRadiance; radiance value below lower bound of coccolith lookup table 723 HiRadiance; radiance value above upper bound of coccolith lookup table 824

L2_flags derived products group 1 byte 3 of 3 (eps_clr_water, CZCS_pigment, chlor_MODIS, pigment_c1_total, chlor_fluor_ht, chlor_fluor_base, chlor_fluor_effic, susp_solids_conc, cocco_pigmnt_conc, cocco_conc_detach, clacite_conc, K_490, phycoeryth_conc, phycou_conc) Product specific tests Parameters (13-25 radiance products) MO*.3{13:25}*.hdf L3 map bit L3 binned bit L2 MODCL2A bit InvalidEntry; invalid data coccolith lookup table199 PEB and PUB input Lw's (8-12) bad210 range_iop_flags[1]: PEB/PUB algorithm calculated IOP outside realistic range 311 range_iop_flags[2]: PEB/PUB algorithm calculated IOP outside realistic range 412 range_iop_flags[3]: PEB/PUB algorithm calculated IOP outside realistic range 513 range_iop_flags[4]: PEB/PUB algorithm calculated IOP outside realistic range 614 range_iop_flags[5]: PEB/PUB algorithm calculated IOP outside realistic range 715 Cloudy >threshold816

L2_flags derived group 2 byte 1 of 2 (chlor_a_2, chlor_a_3, ipar, arp, absopr_coef_gelb, chlor_absorb, tot_absorb_412, tot_absorb_443, tot_absorb_488, tot_absorb_531, tot_absorb_551) Product specific tests Parameters (26-36 radiance products) Map MO*.1{26:36}*.hdf L3 map bit L3 binned bit L2 MODCL2B bit Input Lw’s to Carder Chlorophyll routine (bands 8-13) bad 1259 neg_rrs_flag; One or more remote sensing reflectance values are equal or less than zero low_412_flag; rrs[0](412) less than thresh_ low_555_flag; rrs[4](555) less than thresh_ default_flag ; using default chlorophyll model52913 chl_inconsistent_flag; calculated chlorophyll exceeds chl_incon._thresh Reserved; chl_quality_flag - (currently unused)73115 Reserved;hi_scat_flag - (currently unused)83216

L2_flags derived group 2 byte 2 of 2 (nLw_412, nLw_443, nLw_488, nLw_531, nLw_551, nLw_667, nLw_678, Tau_865, Eps_78, aer_model1, aer_model2) Product specific tests Parameters (26-36 radiance products) MO*.2{26:36}*.hdf L3 map bit L3 binned bit L2 MODCL2B bit blend_flag; aph_model between.03 and.06 (chlorophyll blended) 1171 package_flag ; chlorophyll packaged2182 input nLw’s (bands 8-13) for ipar and arp products bad3193 hi_windspeed; wind speed 12 m/s4204 Cloudy ; 865 > threshold5215 chl_a3, high packaging6226 if (modis sst-ndtsst)> 3.0 ; Carder NDT un-packaged7237 If modis sst-ndtsst )< 1.8; Carder NDT packaged8248

L2_flags SST byte 1 of 2 (SST_D1, SST_N1, SST4_N2) Product specific tests Parameters (37:40 SST products) Map MO*.1{37:40}*.hdf L3 map bit L3 binned bit L2 MOD28 bit SST input radiance bad;negative radiance in any of bands (20,31,32) 1259 SST4 input radiances bad; negative values (20,22,23)22610 Band 31 or band 32 failed uniformity test 1 ( max-min of 3x3 pixel box >0.7) Band 31 or band 32 failed uniformity test 2 ( max-min of 3x3 pixel box >1.2) SST algorithm zenith angle test 1, sat zenith angle> SST algorithm zenith angle test 2, sat zenith angle > Failed SST tree tests SST more than 2 degrees different from reference83216

L2_flags SST products byte 2 of 2 (SST_D1, SST_N1, SST4_N2) Product specific tests Parameters (1-12 radiance products) MO*.2{1:12}*.hdf L3 map bit L3 binned bit L2 MOD28 bit ch20/31/32 brightness temps bad; unreasonable values in one or more bands less than -10 or greater than SST4 algorithm uniformity test 1 ( max-min of 3x3 pixel box >0.7) 2182 SST4 algorithm uniformity test 2 ( max-min of 3x3 pixel box >1.2) 3193 SST4 algorithm zenith angle test 1; sat zenith angle > SST4 algorithm zenith angle test 2; sat zenith angle > Failed SST4 tree tests6226 SST4 more than 2 degrees C different from reference7237 ch20/22/23 brightness temps bad, unreasonable values in one or more bands less than -10 or greater than

L2_flags:Name = "one bit per flag, flag 1 is in the least significant bit" ; L2_flags:Units = "bits" ; L2_flags:f01_name = "blend" ; L2_flags:f02_name = "package" ; L2_flags:f03_name = "IparArp_In" ; L2_flags:f04_name = "hi_wind" ; L2_flags:f05_name = "Cloudy" ; L2_flags:f06_name = "chl_hipackage" ; L2_flags:f07_name = "NDT_package1" ; L2_flags:f08_name = "NDT_package2" ; …………….. Product specific flag metadata

Other useful metadata Processing control INPUTPOINTER CorVer

Processing Control = "REFTYP = 1;AER_MODEL = Quadratic/ Linear 3d; MET1 =……….. ;SUNGLINT1 = 0.005;SOLZEN1 = 70.0;SATZEN1 = 63.0;HIGHTAU1 = 10.00;CLDICE1 = 2.50;COCCOLITH1 = 11.00, 8.10, 1.00, 2.00, 1.00, 1.60, 0.95, 1.50;EPSILON1 = 0.67, 1.50;TURBIDW1 = 3.420;MSKFLG = LAND1;NOAERO = 0;RHO_WN_MAX = 0.010;GlintSC = ;LgCalc = 0;LgSSTc = ;HighAOI = 0;USEPOL = 1;USEAVG = 1;DOCORR = 1;DOAVGCH1 = 2;LAC ;SGLINTTH = 0.017;POLENAB = 1,1,1,1,1,1,1,1,1;RHO_T_MAX = 5.000;USEF0VAR Metadata: Processing control Provides information on various externally controlled thresholds and settings

OBJECT = INPUTPOINTER\n", " NUM_VAL = 75\n", " VALUE = (\"modis_radcor_v12_56.col.hdf\", \"MOD28L2.A hdf\", \"MOD28QC.A h df\", \"MOD021KM.A hdf\", \"MOD03.A hdf\", \"S _NCEP.MET\", \"S _NCEP.MET\", \n", \"S _NCEP.MET\", \"S _EPTOMS.OZONE\", \"S200107rayleigh_modis_667_iqu3.hdf\", \"rayleigh_modis_678_iqu3.hdf\", \ \"new_modis_pol_corr5a.hdf\", \"new_modis_pol_ corr5a.hdf\")\n", ….. Metadata :INPUTPOINTER List all files input to the processing for a given L2 granule Level 3 lists only the first l2 granule that when into the global file

:CorVer = "v12_56: Inter-detector corrs from few grans in each calib Epochs; Bands 8-12 calibrated wrt time trends using modal analysis of Hawaii time series, adjusted absolutely using MOBY data; Cross-scan and mirror-side corrs using the flat-field; rough cal of 6xx bands via a filtered modes (flh consistent); LIMITATIONS: need cross-scan per detector; mirrors-side corrs not stable per Epoch; inter-detector trends in Band 15,16 still reflected in Bands 8-14; 6xx detectors not stable enough" ; Metadata :CORVER Radcor version notes

Where to get data and more information Information locations: MODIS Oceans home page – MODIS Oceans QA Browse 36km Imagery (MQABI) – Select Terra collection 4 Useful links to documentation and related web pages – Data Ordering locations: NASA GES DAAC WHOM (NASA - Goddard DAAC) WHOM, datapool, multi parameter subsetting EOS DATA GATEWAY EDG - JPL PODAAC 4km global SST only

nLw quality Mandatory Quality for all of Gordon's nLw parameters 0 = good, if common flags are clear, and product-specific L2_flags 1-4 and 9-16 are clear. 1 = questionable, if large satellite or solar zenith angles 2 = cloud or sun glint contaminated 3 = bad other than cloud, if any input radiances are negative or saturated, or Atmospheric Correction failed, aerosol model==16,or Land

eps_clr water Quality Mandatory Quality Carder's eps_clr_water parameter 0 = good, if common flags, input Lw flags and product specific L2_flag 15 is clear. 1 = questionable, if any of: shallow, large zenith angles, bad ancillary data, or product-specific L2_flag 15 is set. 2 = cloud or sun glint contaminated 3 = bad, if any input radiances are negative or saturated, or Atmospheric Correction failed, or Land

Chlor_Modis Quality Mandatory Quality for Clark Chlor_MODIS 0 = good, if pigc between 0.01 and 100 mg/m**3 1 = questionable, if high satellite zenith angle, shallow water, bad ancillary data, data values 100 mg/m**3 2 = Sun glint contaminated 3 = input radiances are negative or saturated, cloudy, aersol model==16, land or atmospheric correction problem, pig_c <0.0 mg/m**3

chlor_fluor_ht Quality Mandatory Quality for Abbott's chlor_fluor_ht parameter ( quality level demoted by 1 if high sat or solar zenith angle) 0 = good, if common flags except shallow are clear, input Lw flags are clear, product specific flags clear 1 = questionable, L2_flags 7 (FLH/CHL too large) or L2_flag 9 (FLH too large) 2 = if FLH/Chl way too large, FLH way too large, or modis_chl=-1 3 = bad, if input radiances are negative or saturated, cloudy/albedo, atmospheric correction problem, glint, bad ancillary data, or land

Coccolith quality Mandatory Quality for Gordon/Balch cocco_pigmnt_conc, cocco_conc_detach, calcite_conc 0 = good, if common flags are clear, input Lw flags are clear, and product-specific L2_flags clear. 1 = questionable, if any of: shallow, large zenith angles, bad ancillary or product flags = cloud, if any input radiances are negative and saturated, cloud, or glint 3 = bad, if any input radiances are negative or saturated, or Atmospheric Correction failed, aersol model==16, Land, or L2_flags are set

CZCS Quality Mandatory Quality for Clark's CZCS_pigment parameter 0 = good, if pigc between 0.01 and 100 mg/m**3 1 = if any high satellite zenith angle, shallow water, bad ancillary data, or data vales 100 mg/m**3 2 = Sun glint contaminated 3 = bad, if input radiances are negative or saturated, glint, cloudy, aer0sol model==16, land or atmospheric correction problem, pig_c <0.0 mg/m**3

Pigment_c1_total Quality Mandatory Quality for Clark's pigment_c1_total 0 = good, if pigc between 0.01 and 200 mg/m**3 1 = questionable if any high Sateillite zenith angle, shallow water, bad ancillary data, data vales 200 mg/m**3 2 = Sun glint contaminated 3 = bad, if any input radiances are negative or saturated, glint, cloudy, aersol model==16, land or atmospheric correction problem, pig_c <0.0 mg/m**3

Susp_solids_conc Quality Mandatory Quality for Clark's susp_solids_conc parameter 0 = good, if values between 0.03 and 100 g/m**3 1 = questionable, susp_solid 100 g/m**3, high satellite or solar zenith angle, shallow water, bad ancillary data 2 = sun glint contaminated 3 = bad, if any input radiances are negative or saturated, or AtmosphericCorrection failed, aersol model==16, or susp_solid less than 0.03 or greater than 100 g/m**3, Land, cloudy

K_490 Quality Mandatory Quality for Clark's K_490 parameter 0 = good, K490 between and = questionable, if any values 20.0, high satellite or solar zenith angle, shallow water, or bad ancillary data 2 = glint contaminated 3 = bad, if any input radiances are negative and or saturated, or Atmospheric Correction failed, aerosol model==16, k490 <0.0, Land, or cloudy

chlor_a_3, absorp_coeff_gelb, chlor_absorb,tot_absorb_* Quality Mandatory Quality for Carder's chlor_a_3, absorp_coeff_gelb, chlor_absorb, tot_absorb_* 0 = good, if common flags are clear, input Lw flags are clear, and product-specific L2_flags 1,9-16 are clear 1 = questionable, if any of: shallow, large satellite or solar zenith angles, bad ancillary, aphi675 too small, or low 412 or 555 flag set 2 = glint contaminated 3 = bad, if any input radiances are negative or saturated, or Atmospheric Correction failed, or Land, aerosol model==16, RRS <0

IPAR Quality Mandatory Quality Carder's IPAR 0 = good, if common flags are clear, input Lw flags are clear, and product-specific L2_flags clear 1 = questionable, if any of: shallow, large zenith angles, bad ancillary 2 = cloud or glint contaminated 3 = bad, if any input radiances are negative or saturated, or Atmospheric Correction failed, or Land, or aerosol model==16

ARP Quality Mandatory Quality Carder's ARP parameter 0 = good, if common flags are clear, input Lw flags are clear, and product-specific L2_flags is clear 1 = questionable, if any of: shallow, large satellite or solar zenith angles, bad ancillary, or high windspeed flag set 2 = cloud or glint contaminated 3 = bad, if any input radiances are negative or saturated, or Atmospheric Correction failed, or Land, or aersol model==16, or RRS< 0

Chlor_a2 Quality Mandatory Quality for SeaWiFs analog OC3M Chlorophyll chlor_a2 0 = good, if pigc between 0.01 and 100 mg/m**3 1 = Sat Zenth angle >70, shallow water, bad ancillary data, data values 100 mg/m**3 2 = Sun glint contaminated 3 = input radiances are negative or saturated, glint, cloudy, aersol model==16, land or atmospheric correction problem, pig

11-12um SST Quality Mandatory Quality for SST products 0 = good, if common flags are clear, input radiance flags are clear, and product-specific L2_flags 9,11-16 are clear 1 = questionable, large zenith angle, bad ancillary or flags 3, = sun glint or channel uniformity bad contaminated 3 = if any input radiances are negative and not saturated, or Atmospheric Correction failed, or Land

SST4 Quality Mandatory Quality for SST4 products 0 = good, if common flags are ok, inputs, both sat zenith tests, both sst4-sst, BT22-BT23-ref, both uniformity, brights, and reynolds(optional) 1 = questionable, if any of: if sst4-sst test2, sat zenith test 2, or unif test2 2 = if sst4-sst test 1, sat zenith angle test 1, or uniformity test1 3 = if any input radiances are negative and not saturated, BT22-BT23-ref out of range, brights outside (-4..33)

Valids: Passed Failed Inferred Passed Inferred Failed Being Investigated (default in *.hdf) Suspect Hold Science Quality flag and Explanation ScienceQuality_ (updates in *.met only)