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MOD11A1 Daily LST
The daily level 3 LST product at 1km spatial resolution is a tile of daily
LST product gridded in the Integerized Sinusoidal projection (in V3)
or the Sinusoidal projection (in V4). A tile contains
1200 by 1200 grids in 1200 rows and 1200 columns. The exact grid size at
1km spatial resolution is 0.928km by 0.928km.
Algorithm Description
The daily MOD11A1 LST product is constructed with the results in the MOD11_L2
products of a day through mapping the SDSs of all pixels in MOD11_L2 products
onto grids in the integerized sinusoidal or sinusoidal projection and
averaging the values in each grid.
As latitude increases beyond 30 degrees, the LST value at some grids
in the MOD11A1 product
may be the average value of LSTs retrieved from multiple MODIS observations
in clear-sky conditions in day or night. If LST values from single
clear-sky MODIS observations are required for all grids, the MOD11_L2 LST
product and MODIS geolation product (MOD03) should be used instead.
Scientific Data Sets (SDS)
The SDSs in the MOD11A1 product include LST_Day_1km, QC_Day, Day_view_time,
Day_view_angl, LST_Night_1km, QC_Night, Night_view_time, Night_view_angl,
Emis_31, Emis_32, Clear_day_cov, Clear_night_cov, and
Columns_per_Global_Grid_Row
described in
Table 9.
Note that the scale factor and offset for Day_view_angle and Night_view_angle
in V4 Level-3 MODIS LST products have been changed so that a negative sign
of the viewing angle means MODIS viewing the grid from east. The view zenith
angle itself is always a positive number,
the zenith angle from nadir.
The information of MODIS viewing the grid from east or west may be important
in understanding the view angle effect in the temporal variations in LSTs,
especially in rugged regions.
Table 9. The SDSs in the MOD11A1 product.
SDS
Name |
Long
Name |
Number
Type |
Unit |
Valid
Range |
Fill
Value |
scale
factor |
add
offset |
| LST_Day_1km |
Daily daytime 1km grid
Land-surface Temperature |
uint16 |
K |
7500-65535 |
0 |
0.02 |
0.0 |
| QC_Day |
Quality control for daytime
LST and emissivity |
uint8 |
none |
0-255 |
0 |
NA |
NA |
| Day_view_time |
(local solar) Time of daytime
Land-surface
Temperature observation |
uint8 |
hrs |
0-240 |
0 |
0.1 |
0 |
| Day_view_angle |
View zenith angle of daytime
Land-surface Temperature |
uint8 |
deg |
V3: 0-180
V4: 0-130 |
0
255 |
0.5
1.0 |
0
-65.0 |
| LST_Night_1km |
Daily nighttime 1km grid
Land-surface Temperature |
uint16 |
K |
7500-65535 |
0 |
0.02 |
0.0 |
| QC_Night |
Quality control for nighttime
LST and emissivity |
uint8 |
none |
0-255 |
0 |
NA |
NA |
| Night_view_time |
(local solar) Time of nighttime
Land-surface
Temperature observation |
uint8 |
hrs |
0-240 |
0 |
0.1 |
0 |
| Night_view_angle |
View zenith angle of nighttime
Land-surface Temperature |
uint8 |
deg |
V3: 0-180
V4: 0-130 |
0
255 |
0.5
1.0 |
0
-65.0 |
| Emis_31 |
Band 31 emissivity |
uint8 |
none |
1-255 |
0 |
0.002 |
0.49 |
| Emis_32 |
Band 32 emissivity |
uint8 |
none |
1-255 |
0 |
0.002 |
0.49 |
| Clear_day_cov |
day clear-sky coverage |
uint16 |
none |
0-65535 |
0 |
*0.0001 |
0. |
| Clear_night_cov |
night clear-sky coverage |
uint16 |
none |
0-65535 |
0 |
*0.0001 |
0. |
** Columns_per_
Global_Grid_Row |
Columns per row in the MODLAND
integerized sinusoidal grid |
int32 |
none |
0-43200 |
0 |
1 |
0 |
* The scale_factor 0.0001 was changed to 0.0004 since v2.3.6 and to 0.0005
since v2.5.1.
** SDS Columns_per_Global_Grid_Row is no longer included in the collection 3
MOD11A1.
Local Attributes
The local attributes for SDSs LST_Day_1km and LST_Night_1km are similar
to those in
Table 4.
Global Attributes
Three ECS global attributes and 12 product-specific global attributes are
stored as metadata. The ECS global attributes, CoreMetadata.0,
ArchiveMetadata.0
and StructMetadata.0 are stored as very long character strings in
PVL format.
CoreMetadata.0 contains information about the product during
production and is used to populate the EOSDIS data base for user support.
A listing of objects along with sample values is given in Table
10.
Table 10. CoreMetadata.0 of the MOD11A1
data product.
| Object Name |
Sample Value |
Comment |
| ShortName |
"MOD11A1" |
ESDT name of product |
| VersionID |
1 |
ESC Version |
| ReprocessingActual |
"processed once" |
Number of times processed. |
| ReprocessingPlanned |
"further update is anticipated" |
Expect that products will be reprocessed one
or more times |
| LocalGranuleID |
"MOD11A1.A2000207.h09v05.002.2000246..hdf" |
Name of the granule. |
| DayNightFlag |
"Both" |
|
| ProductionDateTime |
"2000-08-30T05:32:43.000Z" |
Time granule was produced. |
| LocalVersionID |
"SCF V2.2.16" |
Version of algorithm delivered from the SCF |
| PGEVersion |
"2.2.16" |
Version of PGE in MODAPS. |
| InputPointer |
"MOD03.A2000207.1915...hdf", "MOD021KM.A2000207...hdf",
... |
Location of input files in the production
system |
| RangeBeginningDate |
"2000-07-25" |
Beginning and ending times of
the first and last scan line in the swath |
| RangeBeginningTime |
"19:16:40.322353" |
| RangeEndingDate |
"2000-07-05" |
| RangeEndingTime |
"19:18:11.904997" |
| ExclusionGRingFlag |
"N" |
latitude and longitude values
of the corner grids in the tile |
| GringPointLatitude |
[39.995833, 39.995833, 30.004167, 30.004167] |
| GringPointLongitude |
[-117.474532, -104.421223, -92.374445, -103.921832] |
| GringPointSequenceNo |
[1, 2, 3, 4] |
| ParameterName |
"MOD 1KM L3 LST" |
Parameter for which QA statistics are given
in this metadata object. |
| AutomaticQualityFlag |
"Passed" |
Result of automated checks done on the data
during a run of algorithm. Useful for screening for anomalous data. |
| AutomaticQualityFlagExplanation |
"Passed if algorithm ran within
bounds of execution constraints. Suspect if bounds of execution constraints
violated. Failed if PGE failed." |
Explanation of result of automated QA checks
made during execution. |
| ScienceQualityFlag |
"Suspect" |
Set by LST investigator after
post-production investigation |
| SciencelQualityFlagExplanation |
"Early product assessment is
on going. Users are advised to use caution applying these data to
project-applications, especially in semi-arid and arid areas. Input
product are still being refined." |
Explanation of Science Flag |
| QAPercentMissingData |
0 |
0 - 100 |
| QAPercentCloudCover |
95 |
0 - 100 |
| AssociatedPlatformShortName |
"AM-1" |
|
| AssociatedInstrumentShortName |
"MODIS" |
|
| AssociatedSensorShortName |
"CCD" |
|
| **Product Specific Attributes
(PSA)** |
| QAPercentGoodQuality |
5 |
Summary quality assurance statistic
for data product. (0 - 100) |
| QAPercentOtherQuality |
0 |
| QAPercentNotProducedCloud |
95 |
| QAPercentNotproducedOther |
0 |
| N_GRAN_POINTERS |
"5" |
the number of granules
considered for the tile |
| HorizontalTileNumber |
"09" |
|
| VerticalTileNumber |
"05" |
|
| TileID |
"11009005" |
|
| QAFractionGoodQuality |
0.0536014 |
Summary fraction of the LST product.
Range is from 0.0 to 1.0. |
| QAFractionOtherQuality |
0.0000000 |
| QAFractionNotProducedCloud |
0.9463986 |
| QAFractionNotProducedOther |
0.0000000 |
The ECS global attribute ArchiveMetadata.0 contains information
relevant to the input data, an alternate geographic coverage bounds, and
information relevant to version of the algorithm and product. A listing
of objects along with sample values is given in Table
11.
Table 11. ArchiveMetadata.0 of the MOD11A1
data product.
| Object Name |
Sample Value |
Comment |
| HorizontalTileNumber |
"09" |
|
| VerticalTileNumber |
"05" |
|
| AlgorithmPackageAcceptanceDate |
"1997-11-01" |
Algorithm Descriptors |
| AlgorithmPackageMaturityCode |
"pre-launch" |
| AlgorithmPackageName |
"MOD_PR11_V2" |
| AlgorithmPackageVersion |
"Version 2" |
| InstrumentName |
"Moderate-Resolution Imaging SpectroRadiometer" |
|
| ProcessingDateTime |
"2000-08-30T05:32:43.000Z" |
|
| LongName |
"MODIS Level-3 1km Land Surface Temperature
and Emissivity" |
|
| ProcessingCenter |
"GSFC" |
|
| SPSOParameters |
"2484 and 3323" |
|
| LocalInputGranuleID |
"1915" |
only keep the time ID |
| EastBoundingCoordinate |
-92.374445 |
Extent of the tile coverage. |
| WestBoundingCoordinate |
-117.474532 |
| NorthBoundingCoordinate |
39.995833 |
| SouthBoundingCoordinate |
30.004167 |
The StructMetadata.0 global attribute is used by the HDF-EOS
toolkit to create the mapping relationships between the defined grid and
data (SDSs).
Table 12. Listing of objects in the global attribute
StructMetadata.0
in MOD11A1.
| Object |
Definition |
| DIMENSION_1 |
XDim = 1200 |
| DIMENSION_2 |
YDim = 1200 |
| DataField_1 |
DataFieldName=LST_Day_1km |
| DataField_2 |
DataFieldName=QC_Day |
| DataField_3 |
DataFieldName=Day_view_time |
| DataField_4 |
DataFieldName=Day_view_angle |
| DataField_5 |
DataFieldName=LST_Night_1km |
| DataField_6 |
DataFieldName=QC_Night |
| DataField_7 |
DataFieldName=Night_view_time |
| DataField_8 |
DataFieldName=Night_view_angle |
| DataField_9 |
DataFieldName=Emis_31 |
| DataField_10 |
DataFieldName=Emis_32 |
| DataField_11 |
DataFieldName=Clear_day_cov |
| DataField_12 |
DataFieldName=Clear_night_cov |
| DataField_13 |
DataFieldName=Columns_per_Global_Grid_Row |
Quality Assurance
The bit flags defined for the quality assurance SDSs QC_day and QC_Night
are listed in Table 13.
Table 13. Bit flags defined for SDSs QC_day and
QC_Night in MOD11A1. Note that bit 0 is the least significant bit.
A - in V3
| bits |
Long Name |
Key |
| 1 & 0 |
Mandatory QA flags |
00=LST produced, good quality,
not necessary to examine
more detailed QA
01=LST produced, other quality, recommend examination
of
more detailed QA
10=LST not produced due to cloud effects
11=LST not produced primarily due to reasons other
than cloud
(such as ocean grid, grid not covered by all
processed granules) |
| 3 & 2 |
Data quality flag |
00=good data quality
01=LST affected by thin cirrus and/or sub-pixel clouds
10=not processed due to missing pixels
11=not processed due to poor quality |
| 5 & 4 |
Emis Error flag |
00=average emissivity error
<= 0.01
01=average emissivity error <= 0.02
10=average emissivity error <= 0.04
11=average emissivity error > 0.04 |
| 7 & 6 |
LST LST Error flag |
00=average LST error <= 1K
01=average LST error <= 2K
10=average LST error <= 3K
11=average LST error > 3K |
B - in V4
| bits |
Long Name |
Key |
| 1 & 0 |
Mandatory QA flags |
00=LST produced, good quality,
not necessary to examine
more detailed QA
01=LST produced, other quality, recommend examination
of
more detailed QA
10=LST not produced due to cloud effects
11=LST not produced primarily due to reasons other
than cloud |
| 3 & 2 |
Data quality flag |
00=good data quality
01=other quality data
10=TBD
11=TBD |
| 5 & 4 |
Emis Error flag |
00=average emissivity error
<= 0.01
01=average emissivity error <= 0.02
10=average emissivity error <= 0.04
11=average emissivity error > 0.04 |
| 7 & 6 |
LST LST Error flag |
00=average LST error <= 1K
01=average LST error <= 2K
10=average LST error <= 3K
11=average LST error > 3K |
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