CEOSWorking Group on Calibration and Validation

(WGCV)

Report

Agenda item: 17

Presented by: Pascal Lecomte

1) Leading cross-cutting GEO task (DA-06-02) to develop a data quality assurance strategy for GEOSS (broad participation).Completed all three 2008 Category 1 Actions:

• GEO/CEOS Workshop in Gaithersburg, USA• QA4EO (Quality Assurance Framework for Earth Observation)• Dome C prototype calibration campaign

2) Completed two CEOS 2008 category 1 actions related to the climate actions:

• Developed recommendations & strategies for recalibrating historical satellite data to make all measurements consistent, held the Ottawa workshop for reprocessing 1 km data and preparing for the AVHRR workshop in November, in collaboration with GSICS.

• Developed new procedure for guiding the reprocessing / reanalysis of HIRS, using IASI and AIRS.

3) Significant contributions to DA-07-01Global DEM interoperabilityHeld a workshop in Beijing and developed guidelines.

4) All WGCV 2008 CEOS Category 1 Actions are completed, with deliverables (reports, white papers, journal / conference papers) delivered to the CEOS document server (CEOS Google doc).

Accomplishments in the past year

Accomplishments in the past year

Good progress on the Category 2 actions:

For DA-06-02:

Benchmark mission coordination is ongoing with dialog established; draft paper on radiometric standards written; planning for the 2009 radiometer intercomparison in Miami.

Completed the CO2 workshop, and held a special land product validation session at WGCV-29 to address the GEO tasks. WGCV-29 also facilitated the collaboration with WGISS and the SEO.

Thank ESA, BNSC/NPL/UCL, CNES/INRA, NIST/NOAA/NASA, CSA/CCRS/USGS and all participating agencies for supporting the CEOS 2008 actions and for hosting meetings / workshops.

IVOS: The MIAMI-2009 Radiometer

Intercomparison

Current and Future Challenges

• Harmonised and robust Data quality assurance is now of critical importance as the volume of data and number of providers increases rapidly.

• Studies show satellite measurements are inconsistent and more efforts are needed by all space agencies to establish consistency.

• Data quality assurance guidelines (QA4EO) have been developed, by the EO cal/val community led by ESA.

• The next step is the rapid implementation of these guidelines by space agencies.

• Resources for implementing the guidelines, within individual agencies and the facilitation of essential international cooperation and coordination needs to be identified by the space agencies.

WGCV recommendation to CEOS Plenary

• GEOSS must deliver comprehensive “knowledge / information products” worldwide and in a timely manner to meet the needs of its nine “societal benefit areas”. This will be achieved through the synergistic use and combination of data derived from a variety of sources (satellite, airborne and in situ) through the coordinated resources and efforts of the GEO members. Achieving this vision requires the establishment of an operational framework to facilitate interoperability and harmonisation.

• In response to GEO task DA-06-02, and to enable the principles to be implemented in an harmonised manner, a quality assurance (QA) framework was established after discussions held at two international workshops of Cal/Val experts. This Quality Assurance Framework for Earth Observation (QA4EO) consists of a set of operational guidelines derived from “best practices” for implementation by the community.

• The ten key guidelines that underpin this framework were endorsed by the WGCV at their 29th plenary meeting in Avignon, France in September / October 2008. They were also presented to the SIT in October 2008. The WGCV recommends that CEOS endorse the Quality Assurance Framework for Earth Observation and encourage its rapid implementation within member agencies.

• An implementation strategy to encourage broad worldwide use within the full GEOSS community and (if required) its potential evolution to meet any additional specific needs of this community, for example those related to in situ measurements, is now under development.

TMSG recommendation to CEOS Plenary

• A document has been prepared within the context of GEO task DA-07-01. The "Guidelines on Global DEM inter-operability" dated 15 August 2008, include 30 recommendations and 15 actions.

• WGCV and WGISS welcomes the substantial progress made in recent years towards the provision of a global 30m Digital Elevation Model (DEM), although there are still deficiencies in coverage and in validation data. WGCV and WGISS also recognise the importance of DEMs for GEO societal benefit areas and downstream EO data services.

• Therefore it is recommended that CEOS member agencies agree to co-operate in the completion of a complete, gap-free and validated DEM by an agreed goal of June 2010 and no later than June 2011, following the DEM inter-operability guidelines.

• This global DEM should include heights at 30m spacing over land, based primarily on existing proven GDEMs, such as that based on data from the ASTER sensor and for bathymetry down to depths of 30-40m on continental shelves, including the production of a much more accurate coastline especially in the Arctic region.

IVOS recommendation to CEOS Plenary

• The WGCV’s subgroup on Infrared & Visible Optical Sensors (IVOS) aims to ensure high quality calibration and validation of infrared and visible optical data from Earth observation satellites and validation of higher level products.

• IVOS are planning for sensor and post launch ground cal/val support infrastructure intercomparison campaigns in 2009-2010 (visible over land only and infra-red) to establish the degree of equivalence between participants, to ensure robust traceability to SI (via NIST and NPL), and to establish protocols to facilitate future comparisons (GEO task DA-06-02) some of which may be on a regular basis.

• The intercomparison will be carried out following the QA4EO guidelines.

• Preliminary invitations have been circulated and requests for funding to CEOS agencies, to complement that of ESA, have been made.

• IVOS recommends that CEOS members include their sensors in the intercomparison exercises and support the relevant staff to participate in the activities.

ACSG recommendation to CEOS Plenary

• Air Quality (AQ) is an increasing priority with the space agencies (e.g. ESA, NASA, NOAA) and has clear Societal Benefits. Many instruments, for example Envisat-Sciamachy, Aura-OMI, MetOp-GOME/2, are already measuring many key AQ constituents (NO2, HCHO, CHOCHO, SO2, etc.) in the troposphere that require validation.

• Although numerous AQ in situ and remote sensing measurement capabilities exist, these varied techniques are not necessarily inter-comparable and/or are difficult to interpret for satellite validation (field of views, temporal sampling, etc.). A series of ground-based AQ instrument inter-comparisons are planned to quantify the differences in instrumentation, methodologies and algorithms specifically for validation purposes.

• Therefore it is recommended that CEOS encourages satellite agencies (esp. NASA and NOAA) to participate in the air quality ground instrument inter-comparisons organised by ESA. The first campaign is planned for the Summer of 2009.

WGCV Leadership Changes

• Changyong Cao of NOAA completed his two-year term (2006 – 2008) and has stepped down as WGCV Chair

• Pascal Lecomte of ESA (the former WGCV vice-chair) becomes the new Chair for the period 2008 – 2010

• Gregory Stensaas from USGS was elected as the new WGCV vice-chair for the period 2008 – 2010. Greg will become WGCV chair for the period 2010-2012.