Committee on Earth Observation Satellites

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Committee on Earth Observation Satellites Working
Group on Calibration and Validation Report to
12th CEOS Plenary 10th - 12th November,
Bangalore, India Alan Belward WGCV Chair
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1998 Meeting Schedule

• WGCV 14, 21-23 July, 1998, NASDA - Earth
  Observation Research Center, Toyko, Japan.
• Ad hoc WGCV/WGISS/IGOS pilot projects, 24-25
  March 1998, EC, Ispra, Italy.
• SAR Subgroup - 3-6 February 1998, ESTEC,
  Netherlands.
• Microwave Sensors Subgroup - 21-22 April 1998,
  NASA, USA.
• Infra-red and Visible Optical Sensors Subgroup -
  30 September - 3 October 1998, ESTEC,
  Netherlands.
• Terrain Mapping Subgroup - 12 October 1998,
  Montreal.

WGCV Working Group on Calibration Validation
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Directions from 11th Plenary and Actions

• The WGCV has continued to focus on validation of
  higher level products. An ad hoc working group
  will meet in UCL, March 1999.
• Atmospheric chemistry is being dealt with by the
  Working Group, rather than at the sub-group
  level.
• The European Symposium on Atmospheric
  Measurements from Space (January 1999) will
  include discussion on the need for an ad-hoc
  group on atmospheric chemistry cal/val.
• The WGCV met with IGOS pilot projects to examine
  the implications of this initiative (see separate
  report).
• The WGCV has proposed a joint WGCV / ISPRS
  Commission I meeting at the ISPRS 2000 Congress,
  and a joint workshop with ISPRS Commission III
  for June 1999.

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WGCV 14

• The meeting was attended by more than 30
  participants representing 11 CEOS
  member/affiliate agencies.
• All four WGCV subgroups were represented.
• Topics discussed included
• The WGCV three year plan.
• IGOS pilot project requirements.
• Cross cutting strategies for calibration and the
  need for instrumented test sites.
• a special half-day technical session on Japanese
  activities including recent calibration and
  validation activities related to ADEOS and TRMM.

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Action Plan Progress WGCV Pilot Projects

• IVOS Subgroup - infrared intercomparison workshop
  -http//www.rsmas.miami.edu/ir/ceos_minutes.html
  Investigated SST/LST validation methods and
  undertook intercalibration of several IR
  radiometers.
• IVOS Subgroup - IR validation project - data
  collected so far include in-situ measurements,
  AVHRR (AM PM sats), OCTS, ATSR-1 and ATSR-2,
  GMS and planned data include DMSP and data from
  Chinese and Indian satellites.
• TM Subgroup data comparison project - several
  groups are looking at data from IRS and ERS and
  results should be presented towards the end of
  1998.
• see recommendation 1.

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Action Plan Progress Communications

• web site is key http//www.eos.co.uk/ceos-calval
  
• Contains calendar, contact details, test sites
  instruments dossier, links to other cal/val and
  CEOS sites, subgroup information, copies of
  WGCVs newsletters, reports and and meeting
  minutes.
• In period May to August 1998 gt700 different users
  accessed WGCV information.
• Enhancements to web site planned.
• Cal/Val News will be prepared more frequently and
  be enhanced.
• WGCV continues to invite individuals (from non
  CEOS organisations) to meetings as technical
  experts when appropriate.

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Action Plan Progress Communications II

• In addition to sites and instruments, The WG
  believes that the outside (non CEOS agency)
  community needs to have access to information
  such as validation data and reports and
  calibration data sets.
• ...see recommendations 2 3.
• DOSSIER
• Progress has been limited. Plans and concept of
  the dossier for test site data are to be reviewed.

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Action Plan Progress Education And Outreach

• Developing Countries
• areas for participation/interaction are
  validation projects, which in turn are connected
  to WGCV through affiliates. But, affiliates have
  had very limited participation in WGCV and this
  needs to be addressed. See recommendation 4.
• WGCV will focus on developing nations that
  already have an applications development
  programme. This is needed in order to appreciate
  the importance of well-calibrated and validated
  data.
• Slide Set / Brochure
• A slide set providing generic cal/val examples
  and specific cal/val topics is being prepared for
  completion by end of 1998.

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IGOS related activities

• Ad-hoc meeting held with WGISS and IGOS projects
  (24-25 March, 1998) aimed to
• help the IGOS pilot projects identify their
  cal/val and information systems and service
  requirements.
• help the CEOS working groups identify and focus
  elements of their work which supported IGOS pilot
  projects.
• Key results from the meeting were
• pilot projects should work with CEOS Working
  Groups.
• overlapping areas of responsibility were noted.
• CEOS working groups can provide useful support to
  pilot projects.
• however, issues of which groups define
  activities and which groups undertake
  activities was unresolved.

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IGOS Pilot Projects - Cal/val

• Co-ordination requests
• WGCV should make cal/val documents widely
  available.
• A forest test site is needed for DEM validation.
• WGCV should provide visibility and credibility
  for non-IGOS projects.
• WGCV should support thematic cal/val workshops.
• WGCV should provide pointers to libraries of
  GCPs.
• Review requests
• WGCV needs to explore scaling and aggregation
  issues.
• WGCV should provide detailed cal/val information
  and advice.
• Organisational requests
• Joint WGCV//WGISS activities should be sponsored.
  WGs should demonstrate the benefit of integrated
  activity.
• G3OS data group link with WGISS should be formed.
• WGs should emphasise the need for long-term
  support.

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IGOS Pilot Project recommendations I
Recommendations taken to the SIT, Paris March 1998

• Both WGs have a role in ensuring successful pilot
  projects.
• There is a need for closer co-ordination of pilot
  projects and WG activities.
• Pilot project requirements do not necessitate any
  change to WG mandates.
• WG work-plans will need to expand to deal with
  the issues raised by the pilot projects.
• The value of WGCV and WGISS working together on
  specific topics was highlighted.

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IGOS Pilot Project recommendations II

• Affiliate and observer participation in pilot
  projects and WGs is essential and should be
  supported.
• Pilot projects must co-ordinate to test the
  Integrated in IGOS.
• Implementation of the many identified tasks
  represents a large effort which needs support.
• CEOS participants should provide adequate
  resources to ensure that these actions are
  undertaken.

All recommendations accepted by the SIT
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SAR Subgroup

• Chair Dr Yves-Louis Desnos (ESA ESTEC).
• Web site http//www.estec.esa.nl/ceos-sar/
• Workshop 3-6 February 1998 at ESTEC.
• Attended by gt 120 participants viewing 55
  presentations in 7 sessions - SAR Ocean
  Applications, SAR Terrestrial Applications,
  Radarsat, ENVISAT ASAR, Calibration, Processing,
  Future Systems.
• Proceedings published by ESA. (see also
  recommendation 5)
• Activities
• RSI/CSA have released a dataset for radiometric
  and processor calibration studies.
• A white paper on Phase Preserving Processing
  has been drafted and will be proposed as a CEOS
  standard.
• An inventory of published CD-ROMs has been
  started.
• Next meeting November 1999, CNES, Toulouse.

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Microwave Sensors Subgroup

• Chair Dr Elena Lobl (NASA Marshall Space Flight
  Centre). recently taken over from Dr James Shuie.
• Annual Meeting 21-22 April 1998 at MSFC.
• Sensors discussed
• The MSU (microwave sounding unit) 18 years data
  set intercalibration.
• AMSR (advanced microwave scanning radiometer) to
  fly on ADEOS II and EOS PM-1
• CMIS (conical scanning microwave imaging sensor)
  being studied for the NPOESS mission it combines
  imaging and sounding.
• AMSU (advanced microwave scanning unit) was
  successfully launched in May. Preliminary data
  shows the sensor to be performing flawlessly.
• Next meeting March/April 1999, NASA/GSFC.

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Infra-red and Visible Optical Sensors Subgroup

• Chair Dr Chris Mutlow (UK/RAL).
• Meeting 30 September - 3 October 1998 at ESTEC.
• Reviewed CCRS proposal for instrumented test
  sites. Next meeting to include detailed
  discussion and identification of 3-5 optimal test
  sites.
• Technical sessions on calibration and validation
  strategies for POLDER, A/ATSR, MERIS.
• Activities
• very successful CEOS Radiometer intercomparison
  in Miami.
• visible radiometer intercomparison continues. To
  encourage progress and participation the RAL ATSR
  Team put the complete ATSR-2 data set for the
  Libyan Desert Test site on-line.
• Next meeting - April 1999, Bergen Norway, to be
  held in conjunction with WGCV 15. Note support
  for IVOS members attendance, as well as WGCV
  plenary representatives, is critical.

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Terrain Mapping Subgroup

• Chair Prof. Ian Dowman (UCL).
• Meeting 12 October 1998 in Montreal.
• Activities
• dossier inputs have been prepared and submitted.
• Tandem data is being examined with a focus on
  algorithms.
• IRS 1C data is being looked at and a report on
  IRS-1C calibration has been published.
• a case study on validation of DEMS presented at
  IGOS meeting.
• watching the situation regarding the US high
  resolution optical data to track developments
  concerning terrain mapping issues. There are
  concerns as to whether commercial operators will
  provide calibration data (vs derived products).
• monitoring development of Shuttle Radar
  Topography Mission for validation of terrain
  data.
• Next meeting to be decided.

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WGCV Recommendations for Plenary I

• 1. WGCV recommends that CEOS agencies continue
  international collaboration in developing
  calibration data sets and common test sites, and
  continue to provide data for WGCV experiments.
• 2. WGCV recommends that CEOS agencies maintain
  and provide access to archives of co-located
  remote sensing, aircraft and in-situ data
  collected for cal/val campaigns.
• (Where there are specific cases of calibration
  data not being maintained, the issue will first
  be brought to the attention of the agency heads
  and then to CEOS plenary if warranted.)
• 3. WGCV recommends that CEOS participants
  provide the WGCV with WWW links to validation and
  calibration data so WGCV can provide pointers to
  the community (a simple web clearinghouse).

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WGCV Recommendations for Plenary II

• 4. WGCV will continue to organise workshops and
  ad hoc experts groups to examine cal/val of
  thematic products. Based on the outcome of these
  workshops, the issue of creation of WGCV
  subgroups will be considered. WGCV recommends
  that CEOS agencies nominate participants and
  support their attendance at these workshops.
• 5. Successful SAR calibration requires basic
  sensor stability. The CEOS community currently
  uses a single common site over Amazonia (area
  centers at S7, W67) for antenna pattern
  measurements. WGCV recommends the use of a second
  additional site over Greenland to improve
  confidence in radiometric calibration.

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Future Meeting Schedule

• WGCV 15 - April, 1999 Norway
• WGCV 16 - January 2000 India
• Terrain Mapping Subgroup - to de decided
• SAR Subgroup - November 1999 Toulouse, France
• IVOS Subgroup - April 1999, Norway
• Microwave Sensors Subgroup - March/April 1999
  GSFC, USA
• Other meetings
• European Symposium on Atmospheric Measurements
  from Space - 18-22 January 1999 ESTEC,
  Noordwijk, The Netherlands
• Ad-hoc meeting on validation strategies for land
  cover and land surface parameters, UCL, London
  March 1999
• Joint meeting with ISPRS WG III/1, Portland,
  Maine, June 1999.

WGCV Working Group on Calibration Validation
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Conclusions

• WGCV continues to act as a forum for
  debate/comparison and joint projects concerning
  the most appropriate approaches to Cal/Val for
  CEOS agencies.
• WGCV is benefiting from the IGOS initiative. But,
  the learning process is far from over.
• IGOS has highlighted the need for better
  co-ordination concerning val whilst
  underscoring the requirement for continued
  efforts in cal. The consequences for CEOS
  agencies are yet to be defined.
• WGCV is (one) appropriate forum for this debate,
  but only if CEOS agencies of all categories
  participate.