MODAPS PCR 06-004
| PCR Number | 06-004 |
|---|---|
| Date | 2006-02-13 |
| Initiator | Lorraine Remer |
| Abstract | Atmosphere Collection 5 changes. |
| Problem Statement | Land: Positive bias at low AOT. Negative bias at high AOT. Fine modefraction parameter not quantitative. Mass concentration not formulatedcorrectly. Ocean: Fine mode fraction biased high for low values. Mass concentration has wrong magnitude. Land and Ocean: All retrievals including low QA retrievals are included. This leads to confusion in user community. |
| Description of Change | 1. New SDSs. 2. New formulation for mass concentration. 3. New ocean LUT for models 5, 6 and 7 (refractive index now equal to1.35-0.001i, all wavelengths). 4. New land inversion no longer assumes apparent rho_2.1 equal to surfacerho_2.1. 5. New land LUT using different aerosol models and calculated with MieV-RT3. 6. New distribution of land models. 7. New land surface empirical relationships now function of MVI and geometry. 8. Valid ranges for AOT extended to -0.1. |
| Products Affected | M[O|Y]D04_L2 |
| Software Affected | PGE04 |
| Processing String to Receive the Change | Terra Forward, Terra Reprocessing, Aqua Forward, Aqua Reprocessing |
| Downstream Product Effects | The Atmosphere L2 Joint products MODATML2 and MYDATML2 and all of Atmosphere L3 products including Daily Tile and Daily, 8-Day, andMonthly Global Products. |
| Data Granules to be Used for Science Testing | Use Atmosphere 18 day Science Test Data Set. |
| Justification | Recent analysis of ocean size parameter (Kleidman et al., 2005) shows offsetin dust environments. Using realistic refractive index solves problem. MODIS aerosol over land has acquired a bad reputation in some applications. A complete overhaul of the algorithm is necessary. New information,unavailable at launch, on surface reflectance, aerosol models, andpolarization will make the land product much stronger. Overall trying to get high QA product into users' hands. |
| Effective Date for Implementation of Change | |
| Status | Vincent Salomonsom approved on 04/05/06. |
