The Copernicus Sentinel-3 Surface Topography Mission (STM) provides extremely valuable surface elevation information over inland waters, sea ice and land ice, thanks to its orbit that covers high-latitude polar regions, and to its SAR altimeter, which retrieves high-resolution along-track elevation measurements. To ensure that these measurements can be used with confidence, adequate validation of the geophysical retrieval methods, processing algorithms and corrections must be performed, considering independent observations as Reference Measurements.

St3TART (Sentinel-3 Topography mission Assessment through Reference Techniques) is an EU and ESA funded project led by NOVELTIS with a consortium of 17 European partners (CNES, DTU, NPI, vorteX.io, LEGOS, Ocean Next, CLS, LOCEAN, IGE, SERTIT, GIS, CNR-IRPI, NPL, DT/INSU, IRD, M2C, SYRTE). This project aims to generalise the concept of Fiducial Reference Measurements (FRM) for validation of the Copernicus Sentinel-3 STM over inland waters, sea ice and land ice.

To that end, the St3TART project will not only collect existing data and measure new observations during field campaigns, but it will also ensure that these observations meet the criteria of FRM standards and can be used in an operational way for the validation of the Sentinel-3 Land topography mission.

The FRM data will be made available to all users through an FRM Data Hub platform. Lastly, the SCalSIT tool will help identify relevant Copernicus Sentinel-3 STM validation sites over inland waters.

More information about St3TART can be found on the project website: https://sentinel3-st3tart.noveltis.fr/

ESA is pleased to announce the availability of Copernicus Sentinel-3 altimetry data set generated by the NEW ESA Sentinel-3 Thematic Instrument Processing Facilities (T-IPFs). Planned to be deployed in spring 2022 by the ESA Payload Data Ground Segment (PDGS), the LAND T-IPFs are dedicated and specialized delay-Doppler and Level-2 processing chains over Sea-Ice (SI), Land Ice (LI) and Hydrological (HY) surfaces.

Due to some issue detected on SL_L1.004.04 and SL__LST.004.05.00 processing baseline some delays is expected in delivering of SLSTR NTC production and probably in SYN production also. Problem is expected for Copernicus Sentinel 3A starting from sensing 19/01/2022T00:49:52 and for Copernicus Sentinel S3B starting from sensing 19/01/2022T01:51:23

In order to fix issue detected, we turn back to previous processing baseline that will remain operational until further notice.

Copernicus Sentinel 3A SLSTR Production starting from orbit #30884, sensing 2022-01-21T13:48:27 approx, will be generated with previous baseline.

Copernicus Sentinel S3B SLTR Production starting from orbit #19491, sensing 2022-01-21T14:49:29 approx will be generated with previous baseline.

We are pleased to announce the release of new processing baseline OL_L1.002.22.00 for Copernicus Sentinel-3 concerning the following products and cut-dates:

• OLCI Level 1, NRT and NTC timeliness, on 2022-01-20 10:05

More information about the changes and the characterisation of the new products is available in the following product notices:

• S3.PN.OLCI-L1.09 - i1r0 - OLCI L1 PB 3.02 (20220120).pdf

The associated L1 and L2 Sentinel-3 Product Data Format Specification documents are available on Sentinel Online.

We are pleased to announce the release of new processing baseline SL_L1.004.04 and SL__LST.004.05.00 for Copernicus Sentinel-3 concerning the following products and cut-dates:

• SLSTR Level 1, NRT and NTC timeliness, on 2022-01-20 10:05 UTC
• SLSTR Level 2 LST, NRT and NTC timeliness, on 2022-01-20 10:05 UTC

More information about the changes and the characterisation of the new products is available in the following product notices:

• S3.PN-SLSTR-L1.09 - i1r1 - SLSTR L1 PB SL_L1.004.04.00.pdf

Note: the new SL_2_LST processing baseline has no impact on the content of the products, so there is no specific product notice issued.

The associated L1 and L2 Sentinel-3 Product Data Format Specification documents are available on Sentinel Online.

Due to Copernicus Sentinel-3A orbit correction manoeuvre, SLSTR products and SYNERGY products degradation is expected for sensing time from 19/01/2022T07:35:25 to 19/01/2022T07:35:25

Due to Copernicus Sentinel-3A Moon calibration operation a degradation is expected for the following Copernicus Sentinel-3A products:

• SLSTR products for sensing time from 18/01/2022T07:49:48 to 18/01/2022T08:40:18
• SRAL/MWR products for sensing time from 18/01/2022T07:50:48 to 18/01/2022T08:20:26
• SLSTR products for sensing time from 18/01/2022T08:21:10 to 18/01/2022T08:40:18
• OLCI products for sensing time from 18/01/2022T08:33:55 to 18/01/2022T08:40:18
• SYN products degradation as consequence of SLTSR and OLCI products degradation

Due to Copernicus Sentinel-3B orbit correction manoeuvre, SLSTR IR products degradation is expected for sensing time from 12/01/2022T08:18:51 to 12/01/2022T08:28:27

Due to Copernicus Sentinel-3A orbit manoeuvres, SLSTR and OLCI products degradation is expected for the following sensing times:

- from 07/01/2022T00:04:18 to 07/01/2022T00:17:36

- from 07/01/2022T02:06:48 to 07/01/2022T02:17:25

We are pleased to announce the release of a new processing baseline [2.79-A and 1.57-B] for Copernicus Sentinel-3 concerning the following products:

• OL_2_LFR in NRT and NTC timeliness

Information about the changes and the characterisation of the new L2 Land products is available in the following product notice:

• S3.PN.OLCI-L2L.04 - i1r0 - OLCI L2 Land (PB 2.79-A and 1.57B).pdf

The new processing baseline has been released on the 16th of December 2021.

The latest release of the OLCI L2 Land products includes two new evolutions:

• The OLCI Global Vegetation Index (OGVI) product has been renamed according to its scientific definition: Green Instantaneous Fraction of Absorbed Photosynthetically Available Radiation (GIFAPAR)

• All variables containing uncertainty estimates associated to geophysical products have been renamed to better reflect their content: var_err is renamed as var_unc, where var is any geophysical product.

The content of the product is otherwise unchanged and remains fully consistent with the previous Processing Baseline.

Both evolutions are detailed in the Product Notice accompanying the release.

Due to Copernicus Sentinel-3A orbit correction manoeuvre, SLSTR IR, MWR, SRAL, DORIS products degradation is expected for sensing time from 15/12/2021T07:29:18 to 15/12/2021T08:03:50 and also SLSTR VIS from 15/12/2021T07:29:18 to 15/12/2021T07:31:06.

Due to Copernicus Sentinel-3A SRAL annual calibration on 17 December 2021, SRAL production unavailability is expected for sensing time from 17/12/2021 20:21:20 to 17/12/2021 20:22:50

Due to Copernicus Sentinel-3A SRAL annual calibration on 17 December 2021, SRAL production unavailability is expected for sensing time from 17/12/2021 20:21:20 to 17/12/2021 20:22:50

Due to a Copernicus Sentinel-3A orbit correction manoeuvre, degradation of SLSTR Level-1/ Level-2 products is expected for sensing times from 02:55:19 to 03:07:31 on 7 December 2021.

Due to a Copernicus Sentinel-3A orbit correction manoeuvre, degradation of SLSTR Level-1/ Level-2 products is expected for sensing times from 02:55:19 to 03:07:31 on 7 December 2021.

Due to a Copernicus Sentinel-3A orbit correction manoeuvre, degradation of SLSTR Level-1/ Level-2 products is expected for sensing times from 02:50:27 to 03:01:01 on 3 December 2021.

Due to a Copernicus Sentinel-3B orbit correction manoeuvre on 1 December 2021, a degradation in SLSTR Level-1/ Level-2 products is expected for sensing times from 08:15:46 to 08:25:34 on 1 December.

Due to a Copernicus Sentinel-3B orbit correction manoeuvre on 1 December 2021, a degradation in SLSTR Level-1/ Level-2 products is expected for sensing times from 08:15:46 to 08:25:34 on 1 December.

Due to a Copernicus Sentinel-3A orbit correction manoeuvre on 30 November 2021, a degradation is expected in SLSTR Level-1 and Level-2 products for sensing times from 02:36:37 to 02:48:49 UTC on 30 November.

Due to Copernicus Sentinel-3B OLCI Instrument on-board calibration on 11th November 2021, OLCI Level-1 and Level-2 production unavailability is expected for sensing time from 11/11/2021T09:06:03 to 11/11/2021T09:07:13