Overview
The CSR RL06.2 Dynamic Ocean Mascons (RL06.2DO) are monthly GRACE and GRACE-FO mass-anomaly grids derived from the CSR RL06.2 processing system and modified specifically for dynamic-ocean applications. The product is intended to isolate ocean mass redistribution associated with circulation by reducing or removing signals that are not caused by ocean dynamics.
The processing uses GAD-based regularization constraints over the Arctic Ocean and includes dedicated treatment of large earthquake signals in the Japan and Andaman Bay regions. A gravity, rotation, and deformation (GRD) model consistent with Tamisiea et al. (2010) is also computed with the mascon ocean mask and removed from the released dynamic-ocean solution.
Product Summary
| Product | CSR GRACE & GRACE-FO Dynamic Ocean Mascons RL06.2DO, Version 3 |
|---|---|
| Data span | April 2002 through May 2024 |
| Temporal sampling | Monthly |
| Grid sampling | 0.25° longitude/latitude |
| Reported domain | Ocean mascons only; land grid cells are assigned −99999.0 |
| Primary use | Ocean mass transport, circulation studies, model comparison, and assimilation |
| Dataset update | 2025-04-22 |
Processing for Dynamic Ocean Analysis
The RL06.2DO solutions follow the CSR RL06.2 mascon processing framework with changes tailored to oceanographic analysis:
- Arctic regularization: GAD-based regularization constraints are used over the Arctic Ocean to better represent expected ocean variability and reduce processing artifacts.
- Earthquake treatment: Models of the major earthquake signals near Japan and Andaman Bay are removed during processing, following an approach similar to the CSR RL06.2EQ mascons (doi:10.18738/T8/ZE7DUD).
- GRD correction: A barystatic gravity–rotation–deformation model is computed using the product's ocean mask, following the framework of Tamisiea et al. (2010) (doi:10.1029/2009JC005687), and removed from the released mascons.
- Ocean-only output: The files are distributed globally on a quarter-degree grid, but only ocean mascon values are reported.
Companion Grids
The earthquake and GRD signals have already been removed from the RL06.2DO mascons. The corresponding models are supplied as companion grids so experienced users can inspect the corrections, restore them, or substitute alternative models.
The repository includes separate earthquake and GRD component files alongside the primary dynamic-ocean mascon product.
Usage Notes
The RL06.2DO series is designed for studies of internal ocean mass redistribution. Because the barystatic-GRD, earthquake, and globally averaged ocean GAD signals have been removed, the product should not be interpreted as a direct ocean-bottom-pressure record or used without care in global sea-level budget studies.
Users should consult the dataset documentation and the accompanying publication before applying the product to coastal regions, model comparisons, or data-assimilation applications.
Download
Download the RL06.2DO mascons and the companion earthquake and GRD grids from the Texas Data Repository.
Acknowledgement and Citation
Please cite both the data set and the accompanying publication when using the CSR RL06.2DO Dynamic Ocean Mascons.
Data Set
Pie, N., Bonin, J., Tamisiea, M., Chambers, D., and Save, H.: CSR GRACE & GRACE-FO Dynamic Ocean Mascons RL06.2DO, V3, Texas Data Repository [data set], https://doi.org/10.18738/T8/3VUPEW, 2025.
Publication
Bonin, J., Pie, N., Tamisiea, M. E., Chambers, D., and Save, H.: GRACE and GRACE-FO mascons for ocean dynamic applications, Earth Syst. Sci. Data, 18, 3481–3505, https://doi.org/10.5194/essd-18-3481-2026, 2026.