modis ocean filenames, structures, and useful metadata

MODIS OceanFilenames, 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

– http://modis-ocean.gsfc.nasa.govMODIS Oceans QA Browse 36km Imagery (MQABI)

– http://jeager.gsfc.nasa.gov/browsetool/Select Terra collection 4

Useful links to documentation and related web pages– http://modis-ocean.gsfc.nasa.gov/doclinks.html

Data Ordering locations:NASA GES DAAC WHOM (NASA - Goddard DAAC)

http://daac.gsfc.nasa.gov/MODIS/WHOM, datapool, multi parameter subsetting

EOS DATA GATEWAY EDG- http://modis.gsfc.nasa.gov/data/ordering.html

JPL PODAAC 4km global SST only

http://podaac.jpl.nasa.gov/modis

http://modis-ocean.gsfc.nasa.gov/

http://jeager.gsfc.nasa.gov/browsetool/

http://daac.gsfc.nasa.gov/MODIS/

http://modis.gsfc.nasa.gov/data/ordering.html



















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 2 - 5 minute granule; • Level 3 - daily, 8 day week, monthly, yearly

• Other data sets:- SST matchups database ([email protected])- 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 filenames2 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_pigment Chlorophyll-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_conc Phycoerythrobilin 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,N6 Channel 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#}.parameterM*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 19-20. (note: 1-based numbering convention)

QL=<=3 QL=0

Quality level definitions

There are four quality levels

0=good1=questionable/suspect2= sun glint or possible cloud contaminated3=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 OceanFlags, 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 filesAll 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 255Level 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 metadatancdump -h MODOCL2.A2001191.1605.003.2001312071143

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 flagsThe 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 processedBit 2 Atmospheric correction failedBit 3 Satellite Zenith angle >45Bit 4 Solar Zenith angle >70Bit 5 Shallow water

(<5km from coast or <50m deep,or inland lake)Bit 6 Sun glint threshold or cloud 678 homogeniety exceedBit 7 Invalid or missing ancillary dataBit 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; Albedo @ 865 threshold 1 25 9

Bad_Lw; One or more bands missing 2 26 10

Bad_Lw; Any LwXXX <= 0 3 27 11

Bad_Lw; Any band counts < 0 4 28 12

Atmos_Corr; Questionable polarization correction/mirror reflectance (not currently used)

5 29 13

Atmos_Corr; Gordon aerosol failure 6 30 14

Atmos_Corr; epsilon out of range 7 31 15

Atmos_Corr - Any LaXXX <= 0 8 32 16

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


MO*.2{1:12}*.hdf

L3 map

bit

L3 binned bit

L2

MODCL2

bit

Atmos_Corr ; Invalid Raleigh scattering data 1 17 1

nLw550_low; Calculated nLw550 is too small 2 18 2

Cocco; Coccolithophorid radiance exceeds threshold 3 19 3

TurbidCase2; Actual_rrs555 > Turbid_rs555 4 20 4

Hi_la865; Calculated La865 is too large 5 21 5

Input Lw's for Carder's clear water epsilon band (11,13) bad.

6 22 6

lo_eps; epsilon < 0.67 7 23 7

spare 8 24 8

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


Map MO*.1{12:25}*.hdf

L3 map

bit

L3 binned bit

L2

MODCL2

bit

pig_C input Lw’s (bands 9 and 12) bad 1 25 25

chl_a input Lw’s (bands 9,10,11,12) bad 2 26 26

pig_total input Lw’s (bands 9,10,11,12) bad 3 27 27

susp_solid inout Lw’s (bands 9,10,11,12) bad 4 28 28

K490 input Lw’s (bands 9 and 12) bad 5 29 29

FLH/chl_modis way too high, not reasonable 6 30 30

FLH/chl_modis too high, approaching limit higher uncertainty

7 31 31

FLH way too high, not a reasonable value 8 32 32

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


MO*.2{13:25}*.hdf

L3 map

bit

L3 binned bit

L2

MODCL2A

bit

FLH_Range; approaching limit higher uncertainty 1 17 17

chl_modis == -1, algorithm failed, fill value present 2 18 18

ARP qual >= 2, questionable 3 19 19

ARP qual == 1 , higher uncertainty 4 20 20

CFE too high, not reasonable value 5 21 21

coccolith algorithm input Lwís (bands 9 and 12) bad 6 22 22

LoRadiance; radiance value below lower bound of coccolith lookup table

7 23 23

HiRadiance; radiance value above upper bound of coccolith lookup table

8 24 24

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


MO*.3{13:25}*.hdf

L3 map

bit

L3 binned bit

L2

MODCL2A

bit

InvalidEntry; invalid data coccolith lookup table 1 9 9

PEB and PUB input Lw's (8-12) bad 2 10 10

range_iop_flags[1]: PEB/PUB algorithm calculated IOP outside realistic range

3 11 11


4 12 12


5 13 13


6 14 14


7 15 15

Cloudy - albedo @ 865 >threshold 8 16 16

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


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

1 25 9

neg_rrs_flag; One or more remote sensing reflectance values are equal or less than zero

2 26 10

low_412_flag; rrs[0](412) less than thresh_412 3 27 11

low_555_flag; rrs[4](555) less than thresh_555 4 28 12

default_flag ; using default chlorophyll model 5 29 13

chl_inconsistent_flag; calculated chlorophyll exceeds chl_incon._thresh

6 30 14

Reserved; chl_quality_flag - (currently unused) 7 31 15

Reserved;hi_scat_flag - (currently unused) 8 32 16

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


MO*.2{26:36}*.hdf

L3 map

bit

L3 binned bit

L2

MODCL2B

bit

blend_flag; aph_model between .03 and .06 (chlorophyll blended)

1 17 1

package_flag ; chlorophyll packaged 2 18 2

input nLw’s (bands 8-13) for ipar and arp products bad 3 19 3

hi_windspeed; wind speed 12 m/s 4 20 4

Cloudy ; Albedo @ 865 > threshold 5 21 5

chl_a3, high packaging 6 22 6

if (modis sst-ndtsst)> 3.0 ; Carder NDT un-packaged 7 23 7

If modis sst-ndtsst )< 1.8; Carder NDT packaged 8 24 8

L2_flags SST byte 1 of 2 (SST_D1, SST_N1, SST4_N2)


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)

1 25 9

SST4 input radiances bad; negative values (20,22,23) 2 26 10

Band 31 or band 32 failed uniformity test 1

( max-min of 3x3 pixel box >0.7)

3 27 11

Band 31 or band 32 failed uniformity test 2

( max-min of 3x3 pixel box >1.2)

4 28 12

SST algorithm zenith angle test 1, sat zenith angle> 40 5 29 13

SST algorithm zenith angle test 2, sat zenith angle >55 6 30 14

Failed SST tree tests 7 31 15

SST more than 2 degrees different from reference 8 32 16

L2_flags SST products byte 2 of 2 (SST_D1, SST_N1, SST4_N2)



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 35.

1 17 1

SST4 algorithm uniformity test 1 ( max-min of 3x3 pixel box >0.7)

2 18 2

SST4 algorithm uniformity test 2 ( max-min of 3x3 pixel box >1.2)

3 19 3

SST4 algorithm zenith angle test 1; sat zenith angle >40 4 20 4

SST4 algorithm zenith angle test 2; sat zenith angle >55 5 21 5

Failed SST4 tree tests 6 22 6

SST4 more than 2 degrees C different from reference 7 23 7

ch20/22/23 brightness temps bad, unreasonable values in one or more bands less than -10 or greater than 35.

8 24 8

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 = 2.280 2.280 2.280 2.280 2.280 2.260 2.260 2.270 2.270 2.250 2.250;LgCalc = 0;LgSSTc = 0.000 0.000 0.000 0.000;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.A2001073.2000.004.2002183150615.hdf\", \"MOD28QC.A2001073.2000.004.2002183150615.hdf\", \"MOD021KM.A2001073.2000.003.2001183210423.hdf\", \"MOD03.A2001073.2000.003.2001183190535.hdf\", \"S200107312_NCEP.MET\", \"S200107318_NCEP.MET\", \n", \"S200107400_NCEP.MET\", \"S200107212_EPTOMS.OZONE\", \"S200107rayleigh_modis_667_iqu3.hdf\", \"rayleigh_modis_678_iqu3.hdf\", \\"new_modis_pol_corr5a.hdf\", \"new_modis_pol_corr5a.hdf\")\n",…..

Metadata :INPUTPOINTERList all files input to the processing for a given L2 granuleLevel 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 :CORVERRadcor version notes

Where to get data and more informationInformation locations:MODIS Oceans home page

– http://modis-ocean.gsfc.nasa.govMODIS Oceans QA Browse 36km Imagery (MQABI)

– http://jeager.gsfc.nasa.gov/browsetool/Select Terra collection 4

Useful links to documentation and related web pages– http://modis-ocean.gsfc.nasa.gov/doclinks.html

Data Ordering locations:NASA GES DAAC WHOM (NASA - Goddard DAAC)

http://daac.gsfc.nasa.gov/MODIS/WHOM, datapool, multi parameter subsetting

EOS DATA GATEWAY EDG- http://modis.gsfc.nasa.gov/data/ordering.html

JPL PODAAC 4km global SST only

http://podaac.jpl.nasa.gov/modis

http://modis-ocean.gsfc.nasa.gov/

http://jeager.gsfc.nasa.gov/browsetool/

http://daac.gsfc.nasa.gov/MODIS/




















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**31 = questionable, if high satellite zenith angle , shallow water,

bad ancillary data, data values <0.01 or >100 mg/m**32 = Sun glint contaminated3 = 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 qualityMandatory 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 15-17

2 = 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 22-24 are set

CZCS Quality

Mandatory Quality for Clark's CZCS_pigment parameter 0 = good, if pigc between 0.01 and 100 mg/m**31 = if any high satellite zenith angle , shallow water, bad

ancillary data, or data vales <0.01 or >100 mg/m**32 = Sun glint contaminated3 = 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**31 = questionable if any high Sateillite zenith angle, shallow water,

bad ancillary data, data vales <0.01 or >200 mg/m**32 = Sun glint contaminated3 = 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 QualityMandatory Quality for Clark's susp_solids_conc parameter

0 = good, if values between 0.03 and 100 g/m**31 = questionable, susp_solid <0.03 or > 100 g/m**3, high satellite

or solar zenith angle, shallow water, bad ancillary data2 = sun glint contaminated3 = 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 0.016 and 20.01 = questionable, if any values <0.016 or > 20.0 , high satellite or solar zenith angle, shallow water, or bad ancillary data2 = glint contaminated3 = 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 contaminated3 = bad, if any input radiances are negative or saturated, or

Atmospheric Correction failed, or Land, aerosol model==16, RRS <0

IPAR QualityMandatory 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 contaminated3 = bad, if any input radiances are negative or saturated, or

Atmospheric Correction failed, or Land, or aerosol model==16

ARP QualityMandatory 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 contaminated3 = bad, if any input radiances are negative or saturated, or

Atmospheric Correction failed, or Land, or aersol model==16, or RRS< 0

Chlor_a2 QualityMandatory Quality for SeaWiFs analog OC3M Chlorophyll chlor_a2 0 = good, if pigc between 0.01 and 100 mg/m**31 = Sat Zenth angle >70, shallow water, bad ancillary data, data

values <0.01 or >100 mg/m**32 = Sun glint contaminated3 = 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 3,10-11

2 = sun glint or channel uniformity bad contaminated 3 = if any input radiances are negative and not saturated, or

Atmospheric Correction failed, or Land

SST4 QualityMandatory 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:PassedFailedInferred PassedInferred FailedBeing Investigated (default in *.hdf)SuspectHold

Science Quality flag and Explanation

ScienceQuality_<product short name> (updates in *.met only)

modis ocean filenames, structures, and useful metadata

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