MODAPS PCR 17-008
| PCR Number | 17-008 |
|---|---|
| Date | 2017-03-30 |
| Initiator | Hulley, Glynn |
| Abstract | PGE116 v6.0.54. Adopted for operational processing at MODAPS the prototype of the L2 science code developed by the science team at the SCF in MATLab software to an operational PGE (116) by rewriting the process in C. PGE130 v6.0.2. Updated the operational version of the generic L2G code to process the L2 swath product and generate the L2G product (PGE 130). PGE131 v6.0.10, PGE136 v6.0.5. Rewrite the L3 daily and 8-day composite MOD11 suite of PGEs as the equivalent MOD21 L3 PGEs (131 and 136) to generate the gridded daily and 8-day MOD21 products. |
| Problem Statement | Generate suite of new LST products MxD21, MxD21A1D, MxD21A1N and MxD21A2 at MODAPS using a suite of new C6 science algorithms developed by the science team at NASA JPL. |
| Description of Change | The MO[Y]D21 LST 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 for MODIS TIR bands 29, 31 and 32. 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. |
| Products Affected | MOD21, MOD21GD, MOD21GN, MOD21A1D, MOD21A1N, MOD21A2, MYD21, MYD21GD, MYD21GN, MYD21A1N, MYD21A1D, MYD21A2 |
| Software Affected | PGE116 v6.0.54; PGE130 v6.0.2; PGE131 v6.0.10; PGE136 v6.0.5 |
| Processing String to Receive the Change | Terra Forward Processing and Reprocessing. Aqua Forward Processing and Reprocessing. |
| Downstream Product Effects | None. |
| Data Granules to be Used for Science Testing | The LST product suite generated globally for three 16-day periods starting with data day 2003001, 2003193 and 2004209. |
| Justification | The new LST product suite MxD21 has been validated over several land validation sites in the USA. LST retrieved using this new emissivity based algorithm addresses the cold bias of ~3K currently found in the MxD11 LST product over arid regions and has been verified to produce nearly the same quality LST as the operational MxD11 suite of LST products over other land cover types. MxD21 will be produced and distributed in all the collection reprocessing including the C6 reprocessing. This new suite of LST product will be distributed to the public in addition to the MxD11 suite of LST products. |
| Effective Date for Implementation of Change | Completed. |
| Status | Major algorithm development completed. Sadashiva Devadiga approved on 04/04/2017. Michael King approved 04/04/2017. |
