The new MODIS Land Surface Temperature and Emissivity (LST&E) product (MOD21) available in Collection 6 uses a physics-based algorithm to dynamically retrieve both the LST and Emissivity simultaneously for the three MODIS thermal infrared bands (29, 31 and 32) at a spatial resolution of 1 km at nadir. The MOD21 product addresses the documented cold bias of 3-5 K in the MOD11 heritage split-window products over arid and semi-arid regions.
The MOD21 algorithm is based on the ASTER Temperature Emissivity Separation (TES) algorithm, which uses full radiative transfer simulations for the atmospheric correction, and an emissivity model based on the variability in the surface radiance data to dynamically retrieve both LST and spectral emissivity. The TES algorithm is combined with an improved Water Vapor Scaling (WVS) atmospheric correction scheme to stabilize the retrieval during very warm and humid conditions. Simulations and validation results available in the ATBD have shown consistent accuracies at the 1 K level over all land surface types including vegetation, water, and deserts.
The MOD21 product will include a swath (scene) Level-2 daily product, and daily and eight-day Level 3 gridded products in sinusoidal projection.
• Product PI:
• Validated Stage: Stage 1
|Product Name||Terra Prod ID/
|Aqua Prod ID/
|Land Surface Temperature/Emissivity Daily 5-min L2 Swath 1km||MOD21_L2||MYD21_L2|
|Land Surface Temperature/Emissivity Daily L3 Global 1km SIN Grid Day||MOD21A1D||MYD21A1D|
|Land Surface Temperature/Emissivity Daily L3 Global 1km SIN Grid Night||MOD21A1N||MYD21A1N|
|Land Surface Temperature/Emissivity 8-day L3 Global 1km||MOD21A2||MYD21A2|