Further Details on RL05 Re-processing
What do we mean by re-processing?
With this transition, we have replaced both the Level-1B and the Level-2 data products.
||Version 0 & Version 1
The version number of the products can be identified by the data file headers and in the filename. Please see the Product Specification Document and other SDS documents for further details.
The improvements in the new products include improved parameters, processing algorithms, and background gravity models.
The information content of the RL05 GSM files is the same as that of RL04 GSM files, in the sense that both the GSM time-series represent the same mass re-distribution processes: e.g. due to hydrology, cryospheric processes, and variations relative to the background models for the oceans and atmosphere.
More details on the re-processing will be provided shortly.
Replacement SLR-derived C20 values:
The RL05-compatible values of SLR-derived C20 harmonics are provided in the new Technical Note 07 (TN07), available along with other Technical Notes through the GRACE data archives.
CSR & JPL GRACE-SDS recommends that users should replace the C20 values within the CSR/JPL-RL05 GSM files with the corresponding values from TN07.
GFZ GRACE-SDS recommends that users should use as-is the C20 values within the GFZ-RL05 GSM files, and should not replace them with SLR-derived estimates.
The TN07 values of SLR-derived C20 are not inter-changeable with the TN05 values, due to changes in background models, and due to an absence of background rates modeled in the former.
Following SDS Documents have been updated: The updated documents are available from the GRACE archives.
- Level-2 User Handbook (v. 3.0, May 29, 2012)
- Product Specification Document (v. 4.6, May 29, 2012)
- CSR Level-2 Processing Standards Handbook (v. 4.0, May 29, 2012)
Some Relevant Publications:
Bettadpur, S. and the CSR Level-2 Team, "Assessment of GRACE mission performance and the RL05 gravity fields", Paper G31C-02, AGU Fall Meeting, San Francisco, CA Dec 2012. [PDF (2.7 MB)]
Bettadpur, S. and the CSR Level-2 Team, "Insights into the Earth System mass variability from CSR-RL05 GRACE gravity fields," Geophysical Research Abstracts, Vol. 14, EGU2012-6409, EGU General Assembly 2012 [PDF (3.9 MB)]