News related to GRACE-FO Gravity Data

This page is regularly updated and contains important news about GRACE-FO data products from the Science Data System (SDS) as well as useful hints how to use the most recent GRACE-FO RL04 Level-1 and RL06 Level-2 data. Additional information may also be taken from the GRACE-FO SDS Monthly Newsletters.

Further mission news are provided here.

2022

May 2022:

• The GRACE-FO Project Science Data System team is pleased to announce the release of a new Level-1B ACX data set. ACX is an updated hybrid ACC-transplant for the GF2 satellite that uses observations from both the GF1 and GF2 accelerometers. With this, differential non-gravitational forces between GF1 and GF2 are better accounted for, which in turn results in improved monthly gravity fields. The initial release of this data set contains products for 2018-06-22 through 2022-01-31 and can be found in the usual Level-1B RL04 directories at the ISDC ftp server. While the SDS team will strive to adhere to the weekly Level-1 delivery schedule, it is anticipated that at least initially, ACX files will be delivered in a delayed mode (but no later than the monthly Level-2 data deliveries with a latency of ~40 days). The corresponding Level-1 documents will be updated shortly. For the time being, a brief overview of what is contained in the daily ACX tarballs is provided in the following: (1) AC01B: accelerometer thruster model data only (this is the same model as used in the ACT1B product), (2) ACU1B: an updated accelerometer transplant procedure (this contains the thruster free data transplanted to the other spacecraft – no thrusts – accounting for pitch offsets between the spacecraft), (3) ACS1B: an SRP/albedo correction to the transplanted data derived primarily from the GF2 accelerometer data, (4) ACM1B: a correction to the transplanted data to account for drag and other non-conservative forces, and (5) ACH1B: an updated transplant product (this is a replacement for the ACT1B product and can be used in gravity field determination). ACH1B is defined as: ACH = ACU + ACS + ACM + AC0 (for the 3 linear components only).
• Using the new ACH1B products mentioned above (instead of the standard ACT1B products), CSR, GFZ, and JPL have produced & released an updated version RL06.1 of their GRACE-FO Level-2 monthly gravity field time series for the entire mission time span (June 2018 through January 2022). As soon as the delivery of the new ACX files has become operational, the production of monthly RL06 Level-2 products will be ceased and RL06.1 will become the operational version of Level-2 products. Note that GRACE Level-2 products remain at version RL06, and are fully compatible with GRACE-FO RL06.1. TN-13 products are available for GRACE-FO RL06 and RL06.1. AOD1B monthly GAx fields remain unchanged, but have been copied from RL06 to RL06.1 (as GAx*_0601) to minimize interruptions in users workflow and processing scripts.

April 2022:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for February 2022.
  

March 2022:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for January 2022.

February 2022:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for December 2021.

January 2022:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for November 2021.

2021

December 2021:

• An updated version 0004 of the GFZ RL06 and COST-G RL01 GravIS Level-3 products for TWS and OBP has been released and is available for download at ISDC.
• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for October 2021.

November 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for September 2021.

October 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for August 2021.

September 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for July 2021.

August 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for June 2021.
• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for May 2021.

June 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for April 2021.

May 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for March 2021.

April 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for February 2021.

March 2021:

• IMPORTANT NOTE: A preliminary version of the GRACE-FO Level-1 products for the period 2021-02-19 through 2021-02-25 has been accidentally published at ISDC and PODAAC on March, 9th. These data were removed shortly after but still were available for download for a couple of hours. Meanwhile, the correct final version of these products has been published. Please make sure that you are using this final version (with header entries 'date_issued: 2021-03-16').

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for January 2021.

February 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for December 2020.

January 2021:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for November 2020.

2020

December 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for October 2020.

November 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for September 2020.

Oktober 2020:

• An updated version 0003 of the GFZ RL06 and COST-G RL01 GravIS Level-3 products for TWS and OBP has been released and is available for download at ISDC.

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for August 2020.

September 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for July 2020.

August 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for June 2020.

July 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for May 2020.

June 2020:

• GFZ has released an updated version 0002 of its GRACE/GRACE-FO RL06 Level-2B and Level-3 products which are available for download at ISDC. These user-friendly mass anomaly products are visualized and described at the web portal GravIS (Gravity Information Service) which has been updated as well and now incorporates also Level-2B/Level-3 products of the GRACE COST-G RL01 time series (more information about COST-G can be found here)
  
  
• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for April 2020.

May 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for March 2020.

April 2020:

• Monthly GFZ GRACE-FO RL06 normal equations (up to degree/order 96x96) in SINEX format are now also available via ISDC's FTP server.
  
  
• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for February 2020.

March 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for January 2020.

February 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for December 2019.

• Please note that Technical Note TN-14 is the new recommendation by the SDS regarding the replacement of the C(2,0) coefficient (replacing the previous recommendation TN-11)! Further details are provided in the GRACE-FO SDS Newsletter No. 9 & 10 and the Level-2 Release Notes.

January 2020:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for November 2019.

2019

Dezember 2019:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for October 2019.

November 2019:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for September 2019.

October 2019:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for August 2019.

September 2019:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for July 2019.

August 2019:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for June 2019.
  
  
• The GRACE-FO Project Science Data System team is pleased to announce the release of the first Level-1 (1A and 1B) data from the Laser Ranging Interferometer (LRI) technology demonstration instrument. This first release contains products for 2018-06-11 (first LRI instrument power-on) through 2019-07-05, and LRI products beyond 2019-07-05 will be made available in synch with the nominal Level-1 data releases. Please refer to the Level-1 Release Notes for important information, and to the Level-1 handbook for a detailed description of data formats and processing conventions.
  
  
• GFZ has updated its web portal GravIS (Gravity Information Service) with user-friendly mass anomaly products with the last seven months of the GRACE mission and the first ten months of the GFZ GRACE-FO RL06 time series. The complete time series of GravIS Level-2B and Level-3 products covers now the period from April 2002 through May 2019 (173 months).

July 2019:

• CSR, GFZ, and JPL have delivered GRACE-FO Level-2 products for May 2019.

June 2019:

• The GRACE-FO Project Science Data System team is pleased to announce the release of the first GRACE-FO Level-2 data set. Level-2 products comprise monthly gravity field solutions (GSM products) up to degree and order 60 and 96, resp., from CSR, GFZ, and JPL, as well as associated GA* products. This first product release includes gravity field solutions for the following nine months: June 2018, July 2018, October 2018, November 2018, December 2018, January 2019, February 2019, March 2019 and April 2019.

• Please carefully read each processing center’s Level-2 release notes and the available Level-2 documentation for a detailed description of the data, file formats, updates, and user recommendations.

May 2019:

• The GRACE-FO Project Science Data System team is pleased to announce the release of the first GRACE-FO Level-1 (1A and 1B) data set. This first product release includes all Level-1 data necessary for the generation of Level-2 gravity field products. The data span the period from June 2018, initial power-up of the instruments during in orbit check out (IOC), through early May 2019, the most recent data available in the operational Phase E. Subsequent Level-1 products will be made available approximately every 7 days starting on May 30, 2019.
  
  
• Please refer to Level-1 release notes and documentation for a detailed description of the data, file formats, updates, and conventions.
  
  
• Corresponding Level-2 gravity field products will begin to be delivered in the following weeks, with the complete first mission year delivered by end of June 2019. Subsequent Level-2 products will be made available on a regular basis starting in July 2019.