1. CAPACITY Operational Atmospheric Chemistry Monitoring Missions CAPACITY Final Meeting - WP 3400 - Ground Segment synthesis Final Meeting ESTEC02/06/05 Y. BAILLION

2. CAPACITY Final Presentation — 2 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit Ground segment: main assumptions  The main assumptions for the Capacity Ground Segment (CGS) are:  implementation as a development of the current multi-mission ground segment  modular architecture that reuses available standards and proven technologies  distributed processing approach using existing centre of expertise  completed by the “service segment” needed for delivering customised services approach similar to existing operation system like METEOSAT and MSG approach similar for S1, S2 and S3  Services provided by the entities managing the models will be fully operational at the time the Capacity Ground Segment is available.  LEO and GEO instruments mission are systematic : the users do not request specific instrument mode and sensing, the instrument mode and sensing are defined from mission requirement and performed systematically.

3. CAPACITY Final Presentation — 3 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit Service Segment Ground Segment The ground segment among the mission elements  According to the generic scheme, the Sentinels mission elements consist in:  the space segment (including the spacecraft(s) and the launch vehicle)  the ground segment to acquire the data transmitted by the space segment, to perform basic data processing, to archive and disseminate data, to check the data quality, to command and control the mission.  the service segment to provide customised services to the final users.  data sets obtained from other space missions and airborne or ground based observations FOSPDGS ICSCKS Sentinels 4 & 5 satellites Other missions, like METOP & post-EPS Raw dataTC/TM Final Users Basic products NRT distribution Other ground stations Raw data External data Customised services Processed data External data Requests and archive retrieval Airborne & In-situ data

4. CAPACITY Final Presentation — 4 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit Ground segment elements and functions (1/2)  The ground segment architecture could be split into 2 main entities interfacing with 2 supporting elements:  the FOS "Flight Operation Segment" managing all satellite(s) monitoring and controls. It contains the control station which is able to exchange TM/TC with the SC and the control centre which is able to monitor TM and to prepare TC.  the PDGS "Payload Data Ground Segment" ensuring the reception of all the observation data down-linked by the SC, processing, archiving and distributing the data and associated basic products. The archive includes the long-term archive essential in the GMES context  Two supporting elements interfacing with both of these elements: the ICS "Instrument Calibration Segment" managing all validation and quality aspects. the CKS "Cipher Keys Segment" generating and providing to the FOS and PDGS all the Cipher Keys necessary for security concept.  FOS and PDGS are independent, except for the observation plans and for the ICS/CKS.

5. CAPACITY Final Presentation — 5 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit Ground segment elements and functions (2/2)

6. CAPACITY Final Presentation — 6 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit FOS element functions and drivers  No specific elements have been identified for the FOS and adaptation of existing ESA ground segment infrastructure will be probably sufficient  the management of sentinel 4 in a geostationary orbit will nevertheless require specific measure and Flight Dynamic System w.r.t “classical” LEO orbit, but ARTEMIS and METEOSAT experience could be used efficiently  The main functions of the FOS are:  reception of telemetry data from the Space Segment,  reception of the preplanning of the payload,  planning of the platform, w.r.t its orbit and housekeeping  commanding of the Space Segment,

7. CAPACITY Final Presentation — 7 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit PDGS element and drivers (1/2)  No specific elements have been identified for the PDGS w.r.t. the other sentinels  The main functions of the PDGS are:  pre-planning of the payload (if needed) and planning of the processing chain  data processing (including generic lower level processing as well as dedicated processing for selected basic products (in distributed processing facilities)),  centralised archiving (long-term and on-line),  distribution of basic products and lower level data (if needed).  The PDGS infrastructure could also include  The gateways for collecting external data (other satellites, in-situ, airborne…),  Processing centres for generating required basic products  The PDGS will implement up-to-date standards (e.g. EO GRID…)

8. CAPACITY Final Presentation — 8 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit PDGS element and drivers (2/2)  The drivers for the PDGS are:  the NRT requirements for the delivery of Air Quality basic products (< 2h TBC) this is more feasible if it is only based on S4 data the use of complementary data coming from S5 will require the use of Svalbard as the single ground station (but Svalbard possibly overcrowded) or several receiving ground stations except if the requirement is limited to Europe The final compliance is highly dependent of the product tree and dissemination means: –List of successive processing to be performed, data needed for these processing, link to/from data assimilation models, processing time required by the models, dissemination link to users : ftp server, DVBS-RCS link.  the high availability required for an operational system will induce the need of redundancy  the robustness and reliability will require autonomous/validated processing models  The data volume preliminary assessed (around 2 Tbit per day) is similar to (and even smaller than) Sentinels 2 and 3

9. CAPACITY Final Presentation — 9 All rights reserved © 2005, Alcatel Space Observation and Science Business Unit Ground segment: Summary & Conclusion  Conclusions:  The main conclusions are that the CGS is feasible and evidences no show-stoppers.  Nevertheless, specific care has to be paid to: the Payload Data Ground Segment (PDGS) and the development of operational autonomous modelling and processing capabilities allowing automatic procedures, The product tree and dissemination means definition to comply with timeliness requirements the availability of Svalbard receiving ground station possibly overcrowded by the GMES space missions.  The main drivers leading to these conclusions are:  The Near Real Time (NRT) distribution of Air Quality products in 2 h to Final Users,  The processing facilities (models…) operational status (robustness and reliability).  In future studies, more detailed analyses will be needed on the definition of basic products and required processing facilities, as well as on the operational status of the existing models. The different level of processing shall be clearly identified.