The MODIS/Aqua Land Surface Temperature and Emissivity (LST/E) products provide per-pixel temperature and emissivity values in a sequence of swath-based to grid-based global products. The MODIS/Aqua LST/E Daily L3 Global 5 km Grid (Short name: MYD11B1), is tile-based and gridded in the Sinusoidal projection, and produced daily at 5 km spatial resolution.
The MODIS/Aqua version-041 (V41) products ... use a modified version-4 (V4) LST algorithm and version-5 (V5) data inputs. The V41 products primarily address underestimation problems in the V5 Climate Modeling Grid (CMG) products. Recent validation activities reveal that the V5 CMG products underestimate LSTs up to 6K especially in desert and semi-arid regions. The production date for this collection starts with MODIS/Aqua data acquisition from 2007-001. This beginning date is driven by the availability of the MODIS V5 data inputs (level-1B radiance data, geolocation data, cloud mask, atmospheric profiles, and land and snow cover data).
The MODIS/Aqua V4 LST/E L3 Global 5 km Grid product (Short name: MYD11B1) incorporates 5 km pixels, which is produced using the day/night LST algorithm (Wan and Li, 1997). This algorithm extracts average temperatures (in Kelvin) and applies them to a pair of MODIS daytime and nighttime observations. This method yields 1 K accuracy for materials with known emissivities. The six thermal Band emissivities are estimated through a classification-based look-up table (LUT). The data inputs include the MODIS L1B calibrated and geolocated radiances, geolocation, cloud mask, atmospheric profiles, land and snow cover.
The V41 MYD11B1 products are a gridded version of the level-2 LST product (MYD11_L2) mapped and projected on 5 km (precisely 4.63 km) Sinusoidal grids. The MYD11B1 product comprises the following Science Data Set (SDS) layers for daytime and nighttime observations: LSTs, quality control assessments, observation times, view zenith angles, and emissivities from Bands 20, 22, 23, 29, 31, and 32. It also includes daytime and nighttime LSTs generated from the 1 km, Band 31 of the level-2 MYD11_L2 product aggregated to 5 km grids.
The V41 Aqua/MODIS LST/E products, including MYD11B1, are validated to Stage-2 with well-defined uncertainties over a range of representative conditions. Further details regarding MODIS land product validation for the LST/E products are available from the MODIS land team validation site.
The V41 MYD11B1 product’s acquisition range started January 1, 2007 (2007-001), and will continue until the V6 reprocessing completes in 2011. The V41 LST products from 2007-001 will remain consistent with similar products from V4, and hence are amenable to combine them in a time series analysis. Users should exercise caution, and not mix the V4.x (i.e., V4 and V41) and V5 LST products in their analysis.
Data Set Characteristics
Area ~1100 x 1100 km (Latitude/Longitude)
Image Dimensions 240 x 240 (Rows/Columns)
Map Projection Sinusoidal
File Size (Average) .24 MB
Data Format HDF-EOS
Number of Science Data Sets (SDS) 17