1. Calibration Events Working Group GSICS TeleConference 23 October 2012
Rob Roebeling, Harald Rothfuss, and Sebastien Wagner
EUMETSAT

2. Common event logging system
Outline
Background
Common event logging system
Drafting a generic event logging system
Using common standards
Populating the database
Opening up the database
Further Work

3. Background

4. Background – Actions from CGMS and GSICS
Recommendation CGMS (39.12): CGMS Satellite Operators to provide regular information on satellite/ instruments events affecting calibration and establish corresponding websites. (minutes CGMS-39).
Recommendation GSCIS: Satellite operators to provide "a log of satellite / instrument events" to support the identification of "spurious" events/trends in calibrated data sets.

5. Background – Calibrations Events Working Group
EUMETSAT set up the Calibrations Events Working Group (CE-WG) that addresses the actions laid out by CGMS and GSICS.
The Terms of Reference outline the following objectives:
to define Which calibration events should be logged? What information needs to be presented? and How this information should be presented and be made available to external users?;
to propose guidelines for developing a uniform calibration events logging approach for EUMETSAT, which is attuned to approaches adopted by other satellite operators;
to follow recommendations on calibration event logging from external authorities, in particular of CGMS, GSICS and WMO;
to function as a single expert group for all EUMETSAT instrument calibration event logging issues;
to communicate progress, methods and results to GSICS and CGMS.

6. Common Event Logging System

7. Schematic Representation

8. Main Categories Mission Information
General information on the platform and instruments operated in the mission that is relevant to all users of the satellite data
Irregular Events
Events at satellite level that are not occurring systematically and that impact the radiometric or geometric quality of the observations due to instruments calibrations, manoeuvres or miscellaneous.
Processing Events
Updates of the processing algorithms (onboard or ground seg.) or reprocessing events (ground seg.) that modify the radiometric or geometric quality of the observations.
Data Outage
Events that triggered the temporary or definitive end of the data collection.

9. Events Database Events
Operational status changes
(e.g. Switch to operational..)
Command chain anomalies
(e.g. ..)
Operating mode changes (e.g. Switch to rapid scan or full disk mode, Clock errors, ...)
Platform alteration
Platform damages
Instrument maintenance
(e.g. Stray light correction, Ice decontamination, ...)
Instrument alteration
(e.g. Detector temperature changes, Solar diffuser changes, ..)
Instrument damage
(e.g. CCDs failure, Mechanical anomalies, Switch to redundant systems, ..)
Detector configuration
(e.g. Dark current, Space view position, ...)
Events databases already exist at the different space-agencies. The Calibration Events Working Group will propose a list of names for calibration events that follow standard naming conventions, and accommodate the adoption of these names in existing events databases.

10. Adopting to Common Standards
Decide on standards and means to improve traceability and uniformity cross space agencies;
Use common data formats (e.g. NCDF, ..).
Use common naming conventions.
Tie measurements to SI standards.
Adopt to inter-national standards (ISO, OGC, …).
Attune to standards used in other CGMS/GSICS/WMO programs .

11. Populating Database
Most space agencies keep a database satellite events. However, these databases 1) do not keep all required information, 2) do often not contain events from historic missions.
Current satellite events databases do not contain all the information required. Thus, additional information needs to be collected to complete the database.
Populating the database with historic events is requested by the climate community. However, has no priority for the CGMS and GSICS actions!
Knowledgeable users (e.g. ISCCP) may need to be consulted to mine historic events.
Assess what historic events can be made available by the space agencies (some events are confidential, or have not been logged at all (especially older events)).

12. Opening up the Databases
Web Interface
Mission
Calibration Events Database
Users
Mission Events Database

13. Opening up the Databases
Suggestions for reporting interface (e.g. web based data base);
Organise information through data base (and web interface).
Database using common file standards
Website should be high-level enabling intuitive event log searching.
Store everything, but only make a limited amount of information available through the web.

14. Work plan
CGMS and GSICS partners to review the proposed Calibration Events Logging System and to suggest how to achieve a common approach across satellite operators;
GSCIS and CGMS partners to discuss and propose the common standards to adopt;
Space Agencies to define the “high-level” and the “specific” system requirements;
Space Agencies to test system concept through small pilot projects;
Space Agencies to identify Climate Users that can provide information on historic calibration events.

15. Thank You
Any Questions?