HDF-EOS V2 MODIS L2G-lite Land Surface Reflectance File Specification
Revision 1.0 (03/22/2007)
Product ID(s): MOD09 L2G 1DY 250M (MOD09GQ)
Description:
The MODIS 250m Resolution Level-2G (L2G) Land Surface Reflectance
file contains the restructured Level-2 (L2) Land Surface Reflectance data
(observations) which intersects a geographic area, a tile, in the MODIS Land
global Level-3 (L3) grid. The global L3 grid is divided into a number of
tiles, areas with a nominal size of 1100 km by 1100 km (10 deg. by 10 deg.).
The data is stored at a nominal grid resolution of 250m.
The 250m observations are stored in a nested hierarchy of grid cells
with the four finer resolution 250m observations stored in the grid cell
location corresponding to the coarser 500m resolution cells (stored in the
corresponding MOD09GA file) containing data from the same orbit. This product
is meant to be used in conjunction with the 500m product because the important
quality and viewing geometry information is stored in that product.
A single 250m surface reflectance observation consist of the surface
reflectance for Bands 1 and 2, the corresponding Quality Assurance (QA) data,
and the 250m observation coverage (obscov). The observation coverage
field gives a estimate of the intersection between the observation and the grid
cell (relative to the observation area).
To relate to 500m observations that is stored in a seperate corresponding 500m
L2G file (MOD09GA), there is a 250m scan value (q_scan) in MOD09GA that
states whether the corresponding 250m observations from the same orbit are
available for the 500m observation, and also states whether the 250m
observations are from the same or a different scan.
There are also the orbit and granule pointer data that relates the overlapped
orbit and granule information to the corresponding metadata array given in the
archived metadata.
The 500m observations (and corresponding 250m observations) are chosen in the
following four steps:
1. First, one 500m observation in each orbit for each grid cell is selected by
selecting the one with the largest observation coverage.
2. Next, for a 500m grid cell, the 500m observations with the maximum
observation coverage for each orbit are selected and sorted in the order of
ascending orbit numbers (earliest first).
3. For the 250m product, the first criteria is that the 250m observation has to
be from the same orbit as the 500m observation in the same layer. That is, the
observation in the 500m grid cell observation always has the same orbit number
as the four nested 250m observations (within the same layer). Secondarily, if
there are multiple 250m observations from the same orbit within a 250m grid
cell, then the one with the maximum observation coverage is stored. Note that
this means that one or more of the nested 250m grid cells (even in the first
layer) could be a fill value. Also, the 250m grid observation could be from a
different scan than the 500m observation. In either of these special cases
occurs, a bit in the "q_scan" SDS is set in the 500m product.
4. The first layer is then selected using the same compositing criteria as is
used in the 8-day surface reflectance product (as of June 2005). The
observation with the highest score is pulled up to the first layer and stored.
Note that the scoring does not use a maximum observation coverage criteria, it
uses: 1) best observation based on a QA score; and 2) then for observations
with the same QA score and that are close to the smallest observed blue value,
the one with the lowest view zenith angle.
The observation coverage is stored with each observation so the end-user can
always reorder the observations using whatever criteria they want, once they
read them in.
This new format reduces the number of 250m L2G files from two files to
one file per day for each tile. The mapping between the original L2G files and
this new L2G file is:
MOD09GQK -- all SDSs except orb_cov
MODPTQKM -- only obscov
There are two ways to which the observation data can be stored in a L2G
grid file, full and compact. The actual method is specified by the
L2GStorageFormat metadata value. In both methods, the first layer of
observations is stored in a 2 dimensional array. In the full method,
all of the values are stored in a 3 dimensional array with the slowest
varying dimension specifying the observation layer. This is an inefficient
storage method because typically a large number of cells are empty. For
the compact method, the additional observation values are stored in a single
dimensional array, with the dimension corresponding to the number of
additional observations since the beginning of the file. Essentially, the
additional observations are run-length encoded with each observation stored
sequentially for each cell.
In addition, the a run-time parameter may specify that only the first layer
be stored, in which case the additional arrays are not stored.
Points of Contact:
Robert Wolfe
NASA's Goddard Space Flight Center, Code 619
Greenbelt, MD 20771
Principal Investigator:
Eric Vermote
NASA's Goddard Space Flight Center, Code 619
Greenbelt, MD 20771
===========================================================================
Generic Constructs
ECS Metadata Strings:
Notes: "FR" is an abbreviation for "FREE_RANGE".
"D/T" is an abbreviation for "DATE/TIME"
(A) implies that multiple values are stored within a
single array.
A value of "Variable" indicates that this value will vary
according to the granule being processed.
"M" means class M.
CoreMetadata.0
This string will contain the following PVL fields:
# of
Field Name Data Value Value
Type s
GROUP = INVENTORYMETADATA
GROUP = CollectionDescriptionClass
SHORTNAME STRING 1 "MOD09GQ"
VERSIONID STRING 1 Variable
END_GROUP = CollectionDescriptionClass
GROUP = ECSDataGranule
REPROCESSINGPLANNED STRING 1 "further update
is anticipated"
REPROCESSINGACTUAL STRING 1 "reprocessed"
LOCALGRANULEID STRING 1 Variable
DAYNIGHTFLAG STRING 1 Variable
PRODUCTIONDATETIME D/T 1 Variable
LOCALVERSIONID STRING 1 Variable
SIZEMBECSDATAGRANULE DOUBLE 1 Variable
END_GROUP = ECSDataGranule
GROUP = PGEVersionClass
PGEVERSION STRING 1 Variable
END_GROUP = PGEVersionClass
GROUP = InputGranule
INPUTPOINTER STRING FR (A) Variable
END_GROUP = InputGranule
GROUP = RangeDateTime
RANGEBEGINNINGDATE DATE 1 Variable
RANGEBEGINNINGTIME TIME 1 Variable
RANGEENDINGDATE DATE 1 Variable
RANGEENDINGTIME TIME 1 Variable
END_GROUP = RangeDateTime
GROUP = GRing
EXCLUSIONGRINGFLAG STRING 1 "N"
END_GROUP = GRing
GROUP = GRingPoint
GRINGPOINTLATITUDE DOUBLE 4 (A) Variable
GRINGPOINTLONGITUDE DOUBLE 4 (A) Variable
GRINGPOINTSEQUENCENO INTEGER 4 (A) Variable
END_GROUP = GRingPoint
GROUP = ZoneIdentifierClass
ZONEIDENTIFIER STRING 1 "0"
END_GROUP = ZoneIdentifierClass
GROUP = OrbitCalculatedSpatialDomain
** number of containers is equal to "NumberofOrbits" **
ORBITNUMBER INTEGER 1 Variable
EQUATORCROSSINGLONGITUDE DOUBLE 1 Variable
EQUATORCROSSINGDATE DATE 1 Variable
EQUATORCROSSINGTIME TIME 1 Variable
END_GROUP = OrbitCalculatedSpatialDomain
GROUP = MeasuredParameter
PARAMETERNAME STRING FR (A) "MOD09G"
GROUP = QAFLAGS
AUTOMATICQUALITYFLAG STRING 1 Variable
AUTOMATICQUALITYFLAGEXPLANATION
STRING 1 Variable
SCIENCEQUALITYFLAG STRING 1 Variable
SCIENCEQUALITYFLAGEXPLANATION
STRING 1 Variable
END_GROUP = QAFlags
GROUP = QAStats
QAPERCENTMISSINGDATA INTEGER 1 Variable
QAPERCENTOUTOFBOUNDSDATA INTEGER 1 Variable
QAPERCENTINTERPOLATEDDATA INTEGER 1 Variable
END_GROUP = QAStats
END_GROUP = MeasuredParameter
GROUP = AssociatedPlatformInstrumentSensor
ASSOCIATEDPLATFORMSHORTNAME STRING 1 "Terra/Aqua"
ASSOCIATEDINSTRUMENTSHORTNAME STRING 1 "MODIS"
ASSOCIATEDSENSORSHORTNAME STRING 1 "MODIS"
END_GROUP = AssociatedPlatformInstrumentSensor
GROUP = AdditionalAttributes
ADDITIONALATTRIBUTENAME STRING FR (A) Variable
PARAMETERVALUE STRING FR (A) Variable
ADDITIONALATTRIBUTENAME.1 = "QAPERCENTGOODQUALITY"
ADDITIONALATTRIBUTENAME.2 = "QAPERCENTOTHERQUALITY"
ADDITIONALATTRIBUTENAME.3 = "QAPERCENTNOTPRODUCEDCLOUD"
ADDITIONALATTRIBUTENAME.4 = "QAPERCENTNOTPRODUCEDOTHER"
ADDITIONALATTRIBUTENAME.5 = "HORIZONTALTILENUMBER"
ADDITIONALATTRIBUTENAME.6 = "VERTICALTILENUMBER"
ADDITIONALATTRIBUTENAME.7 = "TileID"
ADDITIONALATTRIBUTENAME.8 = "PROCESSVERSION"
ADDITIONALATTRIBUTENAME.9 = "QAPERCENTPOOROUTPUT250MBAND1"
ADDITIONALATTRIBUTENAME.10 = "QAPERCENTPOOROUTPUT250MBAND2"
ADDITIONALATTRIBUTENAME.11 = "RESOLUTIONBANDS1AND2"
ADDITIONALATTRIBUTENAME.12 = "identifier_product_doi"
ADDITIONALATTRIBUTENAME.13 = "identifier_product_doi_authority"
END_GROUP = AdditionalAttributes
END_GROUP = INVENTORYMETADATA
ArchiveMetadata.0
This string will contain the following PVL fields:
# of
Field Name Data Value Value
Type s
GROUP = ARCHIVEMETADATA
GROUP = BoundingRectangle
WESTBOUNDINGCOORDINATE DOUBLE 1 Variable
NORTHBOUNDINGCOORDINATE DOUBLE 1 Variable
EASTBOUNDINGCOORDINATE DOUBLE 1 Variable
SOUTHBOUNDINGCOORDINATE DOUBLE 1 Variable
END_GROUP = BoundingRectangle
GEOANYABNORMAL STRING 1 Variable
GEOESTMAXRMSERROR DOUBLE 1 Variable
LONGNAME STRING 1 "MODIS/Terra Surface
Reflectance Daily L2G Global 250m SIN Grid"
SPSOPARAMETERS STRING 1 "2015"
PROCESSINGCENTER STRING 1 "MODAPS"
NUMBEROFOVERLAPGRANULES INTEGER 1 Variable
NUMBEROFINPUTGRANULES INTEGER 1 Variable
NUMBEROFGRANULES INTEGER 1 Variable
GRANULENUMBERARRAY INTEGER FR(A) Variable
GRANULEPOINTERARRAY INTEGER FR(A) Variable
ORBITNUMBERARRAY INTEGER FR(A) Variable
NUMBEROFORBITS INTEGER 1 Variable
GRANULEBEGINNINGDATETIME STRING "NumberofGranules"
Variable
GRANULEENDINGDATETIME STRING "NumberofGranules"
Variable
GRANULEDAYNIGHTFLAG STRING "NumberofGranules"
Variable
GRANULEDAYOFYEAR INTEGER "NumberofGranules"
Variable
GRANULEBEGINNINGDATETIMEARRAY STRING FR(A) Variable
GRANULEENDINGDATETIMEARRAY STRING FR(A) Variable
GRANULEDAYNIGHTFLAGARRAY STRING FR(A) Variable
NADIRDATARESOLUTION STRING 1 Variable
CHARACTERISTICBINANGULARSIZE DOUBLE 1 Variable
CHARACTERISTICBINSIZE DOUBLE 1 Variable
DATACOLUMNS INTEGER 1 Variable
DATAROWS INTEGER 1 Variable
GLOBALGRIDCOLUMNS INTEGER 1 Variable
GLOBALGRIDROWS INTEGER 1 Variable
MAXIMUMOBSERVATIONS INTEGER 1 Variable
ADDITIONALLAYERS INTEGER 1 Variable
TOTALOBSERVATIONS INTEGER 1 Variable
TOTALADDITIONALOBSERVATIONS INTEGER 1 Variable
COVERAGECALCULATIONMETHOD STRING 1 Variable
FIRSTLAYERSELECTIONCRITERIA STRING 1 Variable
L2GSTORAGEFORMAT STRING 1 Variable
QUALITYCLASSPERCENTAGE250MBAND1 INTEGER 16 Variable
QUALITYCLASSPERCENTAGE250MBAND2 INTEGER 16 Variable
PROCESSINGENVIRONMENT STRING 1 Variable
DESCRREVISION STRING 1 Variable
SYSTEMFILENAME STRING FR (A) Variable
PERCENTPROCESSED INTEGER 1 Variable
PERCENTLAND INTEGER 1 Variable
PERCENTLANDSEAMASKCLASS INTEGER 8 Variable
PERCENTCLOUDY INTEGER 1 Variable
PERCENTSHADOW INTEGER 1 Variable
PERCENTLOWSUN INTEGER 1 Variable
RANKING STRING 1 Variable
KEEPALL STRING 1 Variable
COVERAGEMINIMUM DOUBLE 1 Variable
MAXOUTPUTRES STRING 1 Variable
DEEPOCEANFLAG STRING 1 Variable
CLOUDOPTION STRING 1 Variable
******************************************************************
* 1. The field "L2GStorageFormat" is either "full", "compact"
* or "one layer only".
* 2. The field "CoverageCalculationMethod" is either
* "area" or "volume".
* 3. The field "FirstLayerSelectionCriteria" is either
* "nearest neighbor", "maximum observation coverage" or
* "order of input pointer".
******************************************************************
END_GROUP = ARCHIVEMETADATA
StructuralMetadata.0
This string will be populated automatically by HDF-EOS.
Grid Structure: MODIS_Grid_2D
Dimensions:
Dimension Name Value
YDim:MODIS_Grid_2D "DataRows"
XDim:MODIS_Grid_2D "DataColumns"
Corner Locations:
Corner Values
UpperLeftPointMtrs (Variable, Variable)
LowerRightPointMtrs (Variable, Variable)
Geographic Grid Projection Parameters:
Supported Grids: Integerized Sinusoidal (GCTP_ISINUS)
Sinusoidal (GCTP_SNSOID)
Interrupted Goodes Homolosine (GCTP_GOOD)
Lambert Azimuthal Equal Area (GCTP_LAMAZ)
Projection gridID = GCTP_ISINUS
ProjParam[0] 6371007.181
ProjParam[1 to 7] 0.0
ProjParam[8] 86400
ProjParam[9] 0.0
ProjParam[10] 1.0
ProjParam[11 to 12] 0.0
Spherecode -1
GridOrigin HDFE_GD_UL
Projection gridID = GCTP_SNSOID
ProjParam[0] 6371007.181
ProjParam[1 to 12] 0.0
Spherecode -1
GridOrigin HDFE_GD_UL
Projection gridID = GCTP_GOOD
ProjParam[0 to 12] 0.0
Spherecode 19
GridOrigin HDFE_GD_UL
Projection gridID = GCTP_LAMAZ
ProjParam[0] 6371228.0
ProjParam[1 to 5] 0.0
ProjParam[6] Variable
ProjParam[7 to 12] 0.0
Spherecode 19
GridOrigin HDFE_GD_UL
Grid Structure: MODIS_Grid_3D
Dimensions:
Dimension Name Value
Additional Layers:MODIS_Grid_3D "AdditionalLayers"
YDim:MODIS_Grid_3D "DataRows"
XDim:MODIS_Grid_3D "DataColumns"
Corner Locations: (same as MODIS_Grid_2D)
Geographic Grid Projection Parameters: (same as MODIS_Grid_2D)
===========================================================================
Additional global attributes:
Data
Name Type
maximum_observations INT8
total_additional_observations INT32
l2g_storage_format STRING
NumberLandWater INT32
identifier_product_doi STRING
identifier_product_doi_authority STRING
===========================================================================
DataFields:
The following datafields are always in this file:
num_observations
sur_refl_b01_1
sur_refl_b02_1
QC_250m_1
obscov_1
iobs_res_1
orbit_pnt_1
granule_pnt_1
If the "L2GStorageFormat" metadata value is "full", the following
datafields are also present:
sur_refl_b01_f
sur_refl_b02_f
QC_250m_f
obscov_250m_f
iobs_res_f
orbit_pnt_f
granule_pnt_f
If the "L2GStorageFormat" metadata value is "compact", the following
datafields are also present:
sur_refl_b01_c
sur_refl_b02_c
QC_250m_c
obscov_c
iobs_res_c
orbit_pnt_c
granule_pnt_c
nadd_obs_row
Each datafield has at least the following 4 attributes:
long_name (STRING)
units (STRING)
valid_range (agrees with data type of SDS)
_FillValue (agrees with data type of SDS)
Some datafields also contain the following 5 attributes:
add_offset (float64)
add_offset_err (float64)
calibrated_nt (int32)
scale_factor (float64)
scale_factor_err (float64)
Nadir Data Resolution (STRING -- "250m")
QA index (STRING)
===========================================================================
Name Data Dimensions
Type
num_observations INT8 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
Description:
The number of 250m observations per pixel contained within
this L2G file. In addition, if the value is less than zero,
it means that intersections were not computed for this cell.
If it is -1, it is part of the fill region of the grid. If it
is -2, it is in the area identified as 'non-production' in the
Land Production Mask.
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 22 "Number of observations"
units STRING 4 "none"
valid_range INT8 2 0, 127
_FillValue INT8 1 -1
===========================================================================
Name Data Dimensions
Type
suf_refl_b01_1 INT16 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
suf_refl_b01_f INT16 "Additional Layers:MODIS_Grid_3D",
"YDim:MODIS_Grid_3D",
"XDim:MODIS_Grid_3D"
suf_refl_b01_c INT16 "TotalAdditionalObservations"
metadata value
Description:
MODIS Land Surface Reflectance for Band 1.
"suf_refl_b01_1" is for storing the first layer of observations
and is always stored.
"sur_refl_b01_f" and "sur_refl_b01_c" are for storing the
additional layers of observations. "suf_refl_b01_f" is for the
full format and is stored only if "L2GStorageFormat" is "full".
"suf_refl_b01_c" is for the compact format and is stored only if
"L2GStorageFormat" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 60 Variable
units STRING 11 "reflectance"
valid_range INT16 2 -100, 16000
_FillValue INT16 1 -28672
add_offset FLOAT64 1 0.0
add_offset_err FLOAT64 1 0.0
calibrated_nt INT32 1 5
scale_factor FLOAT64 1 0.0001
scale_factor_err FLOAT64 1 0.0
Nadir Data Resolution
STRING 4 "250m"
Note: The attribute "long_name" is
"250m Surface Reflectance Band 1 - first layer" for "sur_refl_b01_1",
"250m Surface Reflectance Band 1 - additional layers, full"
for "sur_refl_b01_f", or
"250m Surface Reflectance Band 1 - additional layers, compact"
for "sur_refl_b01_c".
===========================================================================
Name Data Dimensions
Type
suf_refl_b02_1 INT16 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
suf_refl_b02_f INT16 "Additional Layers:MODIS_Grid_3D",
"YDim:MODIS_Grid_3D",
"XDim:MODIS_Grid_3D"
suf_refl_b02_c INT16 "TotalAdditionalObservations"
metadata value
Description:
MODIS Land Surface Reflectance for Band 2.
"suf_refl_b02_1" is for storing the first layer of observations
and is always stored.
"sur_refl_b02_f" and "sur_refl_b02_c" are for storing the
additional layers of observations. "suf_refl_b02_f" is for the
full format and is stored only if "L2GStorageFormat" is "full".
"suf_refl_b02_c" is for the compact format and is stored only if
"L2GStorageFormat" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 60 Variable
units STRING 11 "reflectance"
valid_range INT16 2 -100, 16000
_FillValue INT16 1 -28672
add_offset FLOAT64 1 0.0
add_offset_err FLOAT64 1 0.0
calibrated_nt INT32 1 5
scale_factor FLOAT64 1 0.0001
scale_factor_err FLOAT64 1 0.0
Nadir Data Resolution
STRING 4 "250m"
Note: The attribute "long_name" is
"250m Surface Reflectance Band 2 - first layer" for "sur_refl_b02_1",
"250m Surface Reflectance Band 2 - additional layers, full"
for "sur_refl_b02_f", or
"250m Surface Reflectance Band 2 - additional layers, compact"
for "sur_refl_b02_c".
===========================================================================
Name Data Dimensions
Type
QC_250m_1 UINT16 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
QC_250m_f UINT16 "Additional Layers:MODIS_Grid_3D",
"YDim:MODIS_Grid_3D",
"XDim:MODIS_Grid_3D"
QC_250m_c UINT16 "TotalAdditionalObservations"
metadata value
Description:
MODIS Land Surface Reflectance 250m Quality Assurance.
Note: Bits are listed from the MSB (bit 15) to the LSB (bit 0).
Bit(s) Description
14-15 spare (unused)
13 adjacency correction performed; yes (1) or no (0)
12 atmospheric correction performed; yes (1) or no (0)
8-11 band 2 data quality, four bit range;
0000 ( 0) -- highest quality
1000 ( 8) -- dead detector; data interpolated in L1B
1001 ( 9) -- solar zenith >= 86 degrees
1010 (10) -- solar zenith >= 85 and < 86 degrees
1011 (11) -- missing input
1100 (12) -- internal constant used in place of climatological
data for at least one atmospheric constant
1101 (13) -- correction out of bounds, pixel constrained to
extreme allowable value
1110 (14) -- L1B data faulty
1111 (15) -- not processed due to deep ocean or clouds
4-7 band 1 data quality four bit range;
(SAME AS ABOVE)
2-3 spare (unused)
0-1 MODLAND QA bits;
corrected product produced:
00 -- ideal quality all bands,
01 -- less than ideal quality some or all bands;
corrected product not produced due to:
10 -- cloud effects all bands,
11 -- other reasons some or all bands may be fill value;
Note that a value of (11) overrides a value of (01)
"QC_250m_1" is for storing the first layer of observations
and is always stored.
"QC_250m_f" and "QC_250m_c" are for storing the
additional layers of observations. "QC_250m_f" is for the
full format and is stored only if "L2GStorageFormat" is "full".
"QC_250m_c" is for the compact format and is stored only if
"L2GStorageFormat" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 59 Variable
units STRING 9 "bit field"
valid_range UINT16 2 0, 4096
_FillValue UINT16 1 2995
Nadir Data Resolution
STRING 4 "250m"
QA index STRING 1800 Variable
Note: The attribute "long_name" is
"250m Reflectance Band Quality - first layer" for "QC_250m_1",
"250m Reflectance Band Quality - additional layers, full"
for "QC_250m_f", or
"250m Reflectance Band Quality - additional layers, compact"
for "QC_250m_c".
==========================================================================
Name Data Dimensions
Type
obscov_1 INT8 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
obscov_f INT8 "Additional Layers:MODIS_Grid_3D",
"YDim:MODIS_Grid_3D",
"XDim:MODIS_Grid_3D"
obscov_c INT8 "TotalAdditionalObservations"
metadata value
Description:
Observation coverage is an estimate of the amount of intersection
between observation footprint and grid cell.
"obscov_1" is for storing the first layer of observations
and is always stored.
"obscov_f" and "obscov_c" are for storing the
additional layers of observations. "obscov_f" is for the
full format and is stored only if "L2GStorageFormat" is "full".
"obscov_c" is for the compact format and is stored only if
"L2GStorageFormat" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 49 Variable
units STRING 7 "percent"
valid_range INT8 2 0, 100
_FillValue INT8 1 -1
add_offset FLOAT64 1 0.0
add_offset_err FLOAT64 1 0.0
calibrated_nt INT32 1 5
scale_factor FLOAT64 1 0.01
scale_factor_err FLOAT64 1 0.0
Note: The attribute "long_name" is
"Observation coverage - first layer" for "obscov_1",
"Observation coverage - additional layers, full" for "obscov_f", or
"Observation coverage - additional layers, compact" for "obscov_c".
===========================================================================
Name Data Dimensions
Type
orbit_pnt_1 INT8 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
orbit_pnt_f INT8 "Additional Layers:MODIS_Grid_3D",
"YDim:MODIS_Grid_3D",
"XDim:MODIS_Grid_3D"
orbit_pnt_c INT8 "TotalAdditionalObservations"
metadata value
Description:
Pointer to the orbit information for each 250m observation. This value
is zero relative, with zero (0) refering to the first orbit in the
"OrbitCalculatedSpatialDomain" HDF EOS inventory metadata group.
"orbit_pnt_1" is for storing the first layer of observations
and is always stored.
"orbit_pnt_f" and "orbit_pnt_c" are for storing the
additional layers of observations. "orbit_pnt_f" is for the
full format and is stored only if "L2GStorageFormat1km" is "full".
"orbit_pnt_c" is for the compact format and is stored only if
"L2GStorageFormat1km" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 42 Variable
units STRING 6 "none"
valid_range INT8 2 0, 15
_FillValue INT8 1 -1
Note: The attribute "long_name" is
"Orbit pointer - first layer" for "orbit_pnt_1",
"Orbit pointer - additional layers, full" for "orbit_pnt_f", or
"Orbit pointer - additional layers, compact" for "orbit_pnt_c".
===========================================================================
Name Data Dimensions
Type
granule_pnt_1 UINT8 "YDim:MODIS_Grid_2D",
"XDim:MODIS_Grid_2D"
granule_pnt_f UINT8 "Additional Layers:MODIS_Grid_3D",
"YDim:MODIS_Grid_3D",
"XDim:MODIS_Grid_3D"
granule_pnt_c UINT8 "TotalAdditionalObservations"
metadata value
Description:
Pointer to the granule information for each 250m observation. This value
is zero relative, with zero (0) refering to the first overlap granule in the
"GranulePointerArray" HDF EOS ArchiveMetadata group.
"granule_pnt_1" is for storing the first layer of observations
and is always stored.
"granule_pnt_f" and "granule_pnt_c" are for storing the
additional layers of observations. "orbit_pnt_f" is for the
full format and is stored only if "L2GStorageFormat1km" is "full".
"orbit_pnt_c" is for the compact format and is stored only if
"L2GStorageFormat1km" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 42 Variable
units STRING 6 "none"
valid_range UINT8 2 0, 254
_FillValue UINT8 1 255
Note: The attribute "long_name" is
"Granule pointer - first layer" for "granule_pnt_1",
"Granule pointer - additional layers, full" for "granule_pnt_f", or
"Granule pointer - additional layers, compact" for "granule_pnt_c".
===========================================================================
Name Data Dimensions
Type
nadd_obs_row INT32 "DataRows" metadata value
Description:
The number of additional observations in each row in the
compact storage form of the L2G grid.
This field is only stored if "L2GStorageFormat" is "compact".
HDF Attributes:
Number of
Values or
Max.
Attribute Data String Value
Type Length
long_name STRING 41 "Number of additional observations
per row"
units STRING 4 "none"
valid_range INT32 2 0, INT32_MAX
_FillValue INT32 1 -1
=========================================================================