MYD11B2 v006

MODIS/Aqua Land Surface Temperature/Emissivity 8-Day L3 Global 6 km SIN Grid


PI: Zhengming Wan

Description

The MYD11B2 Version 6 product provides an average 8-day per pixel Land Surface Temperature and Emissivity (LST&E) in a 1,200 by 1,200 kilometer (km) tile with a pixel size of 5,600 meters (m). Each temperature and emissivity pixel value in the MYD11B2 is a simple average of all the corresponding values from the LST&E values from the MYD11B1 product collected during that 8-day period. Each MYD11B2 granule consists of 19 layers including daytime and nighttime layers for LSTs, quality control assessments, observation times, view zenith angles, and number of clear sky observations along with percentage of land in the tile and emissivities from bands 20, 22, 23, 29, 31, and 32. Unique to the MOD11B products are additional day and night LST layers generated from band 31 of the corresponding 1 km MYD11_L2 swath product aggregated to the 6 km grid.

Characteristics

Improvements/Changes from Previous Versions

  • Removed cloud-contaminated LSTs from Level 2 and Level 3 LST products.
  • Updated the coefficient look-up table (LUT) for the split-window algorithm with comprehensive regression analysis of Moderate Resolution Imaging Spectroradiometer (MODIS) simulation data in bands 31 and 32 over wide ranges of surface and atmospheric conditions, especially extending the upper boundary for (LST – Ts-air) in arid and semi-arid regions. Increased the overlap between various sub-ranges to reduce the sensitivity of the algorithm to uncertainties in the input data (i.e., column water vapor and air surface temperature from MYD07).
  • Made minor adjustments in the classification-based surface emissivity values, especially for bare soil and rocks land cover types.
  • Tuned the day/night algorithm by adjusting weights to improve performance in desert regions where the incorporated split-window algorithm may not work well.
  • Generated new gridded LST&E products with a 6 km spatial resolution for 8-day (MYD11B2) and monthly (MYD11B3) intervals in response to user community requests.

Product Maturity

Validation at stage 2 has been achieved for all MYD11 LST&E products. Further details regarding MODIS land product validation for MYD11B1 data products is available from the MODIS land team validation site.

Collection and Granule

Collection

Characteristic Description
CollectionAqua MODIS
DOI10.5067/MODIS/MYD11B2.006
File Size~0.2 MB
Temporal ResolutionMulti-Day
Temporal Extent2002-07-04 to Present
Spatial ExtentGlobal
Coordinate SystemSinusoidal
DatumN/A
File FormatHDF-EOS
Geographic Dimensions1200 km x 1200 km

Granule

Characteristic Description
Number of Science Dataset (SDS) Layers19
Columns/Rows200 x 200
Pixel Size5600 m

Layers

SDS Name Description Units Data Type Fill Value No Data Value Valid Range Scale Factor Additional Offset
LST_Day_6km Day Land Surface Temperature Kelvin 16-bit unsigned integer 0 N/A 7500 to 65535 0.02 N/A
QC_Day Daytime LST Quality Indicators Bit Field 8-bit unsigned integer N/A N/A 0 to 255 N/A N/A
Day_view_time Local time of day observation Hours 8-bit unsigned integer 255 N/A 0 to 240 0.1 N/A
Day_view_angl View zenith angle of day observation Degree 8-bit unsigned integer 255 N/A 0 to 130 N/A -65
LST_Night_6km Night Land Surface Temperature Kelvin 16-bit unsigned integer 0 N/A 7500 to 65535 0.02 N/A
QC_Night Nighttime LST Quality indicators Bit Field 8-bit unsigned integer N/A N/A 0 to 255 N/A N/A
Night_view_time Local time of night observation Hours 8-bit unsigned integer 255 N/A 0 to 240 0.1 N/A
Night_view_angl View zenith angle of night observation Degree 8-bit unsigned integer 255 N/A 0 to 130 N/A -65
Emis_20 Band 20 emissivity N/A 8-bit unsigned integer 0 N/A 1 to 255 0.002 0.49
Emis_22 Band 22 emissivity N/A 8-bit unsigned integer 0 N/A 1 to 255 0.002 0.49
Emis_23 Band 23 emissivity N/A 8-bit unsigned integer 0 N/A 1 to 255 0.002 0.49
Emis_29 Band 29 emissivity N/A 8-bit unsigned integer 0 N/A 1 to 255 0.002 0.49
Emis_31 Band 31 emissivity N/A 8-bit unsigned integer 0 N/A 1 to 255 0.002 0.49
Emis_32 Band 32 emissivity N/A 8-bit unsigned integer 0 N/A 1 to 255 0.002 0.49
LST_Day_6km_Aggregated_from_1km Daytime LST aggregated from 1km Kelvin 16-bit unsigned integer 0 N/A 7500 to 65535 0.02 N/A
LST_Night_6km_Aggregated_from_1km Nighttime LST aggregated from 1km Kelvin 16-bit unsigned integer 0 N/A 7500 to 65535 0.02 N/A
Clear_sky_days Days in clear sky condition Bit Field 8-bit unsigned integer N/A N/A 0 to 255 N/A N/A
Clear_sky_nights Nights in clear sky condition Bit Field 8-bit unsigned integer N/A N/A 0 to 255 N/A N/A
Percent_land_in_grid Percentage of land in the grid Percent 8-bit unsigned integer 0 N/A 1 to 100 N/A N/A

Product Quality

The Quality Control (QC) layers are stored in an efficient bit-encoded manner. The unpack_sds_bits executable from the LDOPE Tools is available to the user community to help parse and interpret the QC layers.

The QA bit flags for the QC layers are provided in the User Guide on page 25.

Known Issues

For complete information about the MYD11B2 known issues please refer to the MODIS Land Quality Assessment website.

Documentation

Using the Data

E-Learning

Getting Started with MODIS Version 6 Land Surface Temperature Data Part 3: Interpreting Quality Information

Tools

Citation

DOI: 10.5067/MODIS/MYD11B2.006

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