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

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

Background

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.

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.

Common Event Logging System

Schematic Representation

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.

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.

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 .

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)).

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

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.

Work plan 2012-2013 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.

Thank You Any Questions?