We are pleased to announce new processing baselines for Copernicus Sentinel-3 concerning the following products:
[OL_L1.003.03.00] = OL_1_EFR in NTC and OL_1_ERR in NTC timeliness, delivered by ESA
[SYN_L2_.002.18.01] = SY_2_SYN and SY_2_VGP in NTC and STC timeliness delivered by ESA
[SYN_L2V.002.09.01] = SY_2_VG1 and SY_2_V10 in NTC and STC timeliness delivered by ESA
[AOD_NTC.002.08.01] = SY_2_AOD in NTC timeliness delivered by ESA
This Processing Baseline includes major changes for both OLCI and SYNERGY :
Concerning the definitions of OLCI L1B flag definitions, the detection and flagging of pixels that include partially saturated spectra, an update in geometric spatial regridding to improve image continuity between the OLCI cameras, and a routine revision of OLCI geometric and radiometric calibration.
Concerning the Spectral response functions, used to transform OLCI/SLSTR radiometric information into VGT band information, now updated and aligned with PROBA-V; the inclusion of SLSTR calibration factors and OLCI offsets defined during tandem mission; a correction regarding MIR radiometric values and the handling of saturation AOD and NDVI values.
Detailed information about the changes and the characterisation of the new versions of all these products is available in the following product notices:
Worse than usual orbit accuracies have been obtained in the Sentinel-1A POD predicted orbit file (AUX_PREORB) for the past months due to the high solar activity. The S-1 SAR Mission Performance Cluster (SAR MPC) has confirmed that the current levels of accuracy of the predicted orbit files are still good enough to support the SAR focusing. Restituted orbit files (AUX_RESORB) show no routine degradation, except for a few cases in which strong solar geomagnetic storms took place – these were reported as dedicated S1 Quality Disclaimers (ie https://sar-mpc.eu/disclaimer/167/). Precise orbit files (AUX_POEORB) are in principle not affected by the higher solar activity.
In order to quantify the degradation in the predicted orbit files, the AUX_PREORBs are routinely compared against the combined solution, which is a weighted average of non-time critical precise orbit products generated by the members of the Copernicus POD Quality Working Group (CPOD QWG), and is taken as reference to assess the accuracy requirements. The comparisons since the AUX_PREORB are generated are shown below, together with the F10.7 solar flux index, where the strong correlation between the increasing solar activity and the reported degradation can be observed. We attach also the 1-sigma per year (the value below which 68% of the comparisons are) of the AUX_PREORB and the S-1A GPS on-board navigation solution (which was used before the AUX_PREORB to support SAR focusing). This illustrates that predicted orbits are still much better than the navigation solution, even considering the recent worsening.
For context, the solar activity varies with a 11-year cycle. When there is high solar activity, a combination of effects makes the orbit computation more challenging: on the one hand, GNSS observations on-board become noisier due to the effects of the solar flux on the receiver; on the other hand, and more relevant for Precise Orbit Determination (POD), the atmosphere becomes more difficult to model because it changes its state more rapidly. This is especially cumbersome in predicted and near-real time products because predicted solar coefficients are used which then may differ greatly from the observed ones. The impact is especially remarkable when there are strong solar geomagnetic storms, of which there have a few occurrences in the past few months (e.g. 23/03/2023 and 23/04/2023).
At the Copernicus POD Service we are taking action to mitigate the effects of the high solar activity in the two mentioned fronts:
The CPOD QWG has issued a recommendation to modify the tracking settings of the GPS receivers on-board the Copernicus Sentinel satellites to reduce the impact of the high solar flux on the observations.
The CPOD Service is carrying out analysis to find a more robust predicted orbit parametrization which allows to model better the atmosphere, and is also assessing the possibility to update more frequently the solar coefficients.
Any future update or noteworthy degradation will be properly communicated through this channel, and via dedicated Quality Disclaimers if it impacts any AUX_RESORB or AUX_POEORB products. In addition, further information and any status update will be reported at the FRINGE ’23 (11-15 September 2023, University of Leeds).
Following the unscheduled downtime of the International Access Hub, the Sentinel-5P PreOps and the Collaborative Data Hub Node 3 occurred on 14 July 2023 at 13:20 UTC due to a power grid failure in our Greek datacentre, the Sentinels data access services have been successfully restored at 18:30 UTC of the 16th of July.
Products publication backlog has been gradually restored and eventually completed on the 17th of July.
We apologise for the inconvenience that this might have caused to your activities.
Following a power failure in our Data Centre in Greece, the backup supply systems were not able to supply the demand due to the extreme heat wave and failed.
The infrastructure provider is currently working with its suppliers to fix the issue. The current estimate is that the issue will be resolved late on Sunday the 16th of July.
Affected Copernicus services are:
International Access Hub, Sentinel-5P PreOPs and ColHub Node3.
An update of the Copernicus Sentinel-5 Precursor (S5p) operational ground-processing system is planned to start in the morning of 19 July 2023 and finish by 20 July in the afternoon. This includes the addition of new variables related to a new parameter ‘SO2 Layer Height’ into the SO2 product, as detailed in the news of 30 May 2023.
Full detailed information will be provided within the SO2 documentation after the operational switch.
Please note that NRT products for data acquired during the downtime period will be not generated. After the successful deployment of the new system, version numbers of the first orbit generated with the new version of the operational processor both, in NRT and OFFL, will be provided.
On 12 July, the ESA Dunia EO Africa KO event took place with GeoVille as the prime contractor. Their team and partners are working on a Services that will enhance the usage of Copernicus data in Africa. They plan to provide innovative technology solutions that will improve EO data accessibility and exploitation in Africa by leapfrogging infrastructure bottlenecks. They also plan to support the direct interpretation of Copernicus data and develop solutions with low bandwidth consumption and an interface suitable for hand-held mobile devices.
The potential benefits of Earth Observation in supporting sustainable developments in Africa are well recognized. According to Dr. Tidiane Ouattara, on behalf of the African Union Commission, Earth Observation and the monitoring of Africa's abundant natural resources are important for conserving the welfare of current and future generations.
However, Africa remains the lowest user of Copernicus Sentinels data from the ESA dissemination systems at the continental level. To change this reality, Dunia plans to provide users with an application hub, datasets over Africa, user support, and front-end after three months from now.
Copernicus Sentinel-2 has systematically mapped Earth’s southernmost continent, as part of an ad-hoc acquisition campaign implemented by ESA.
Triggered by a request from scientists working in Antarctica, the campaign is expected to enable a range of investigations into processes impacted by climate change, from long-term ice losses to seasonal snow melt, and many more.
It was completed by Sentinel-2B over a one-month period earlier this year and will be repeated every 12 months during each Austral summer.
The enhanced coverage offered by Sentinel-2B will enable collaborative investigations with NASA's Landsat-8 satellite, which is already systematically covering Antarctica.
Sentinel-2B data collected as part of the campaign could support research completed by the dozens of research facilities located on the continent, including the French-Italian Concordia station on the Antarctic plateau.
The initial request that triggered the campaign came from the University of Grenoble in France, and the data are free and open to all scientists and researchers.
Calling on all interested users of Sentinel data, who would like to submit their results, turning their experiences into 'success stories'.
If you have a good story to tell, of how any of the Sentinel satellites are producing data that bring benefit to your work and/or to society, please contact the Sentinel Online Editors at: firstname.lastname@example.org with your proposals.