YvesLouis DESNOS ESAESRIN Chair CEOS WGCV

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Yves-Louis DESNOS ESA-ESRINChair CEOS WGCV
Working Group on Calibration Validation

• WGCV report

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INTRODUCTION TO WGCV
Working Group on Calibration Validation

• Background
• The WGCV was established in 1984 after the
  recognition that proper Calibration and
  Validation are necessary to ensure the clear and
  quantitative understanding of the data and
  derived products from Satellite Earth
  Observation.
• Objectives
• The objectives of the WGCV are to promote
  international cooperation in the domains of
  calibration of data from space-borne sensors and
  the validation of associated geophysical
  parameters and derived products.
• Organization
• The WGCV works according to a three-year work
  plan, approved at plenary
• The WGCV meets every 9 months in Plenary
• The WGCV comprises six subgroups
• Chairmanship
• The WGCV is chaired by ESA since November 2000
  for a period of three years

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INTRODUCTION TO WGCV
Courtesy National Satellite Meteorological Center
of China
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INTRODUCTION TO WGCV
Courtesy National Satellite Meteorological Center
of China
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CEOS WGCV Subgroups update
Working Group on Calibration Validation
WGCV (ESA)

• Synthetic Aperture Radar (SAR)
• Chair Dr M.Shimada, NASDA
• Infrared Visible Optical Sensors(IVOS)
• Chair Dr M.Rast, ESA
• Microwave Sensors
• Chair Dr M. Martin-Neira, ESA
• Terrain Mapping (TM)
• Chair Prof. J. Peter Muller, UCL
• Land Product Validation (LPV)
• Chair Dr J. Morissette, NASA
• Atmospheric Chemistry (ACSG)
• Chair Dr E.Hilsenrath, NASA

SAR (NASDA)
IVOS (ESA)
MS (ESA)
TM (UCL)
LPV (NASA)
ACSG (NASA)
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Working Group on Calibration Validation
CEOS 5 years plan

• Priority actions for WGCV
• The WGCV will support calibration and validation
  activities relating to the IGOS themes,
  particularly through the focused work of the WGCV
  subgroups.
•  The WGCV will actively co-operate with the
  ISPRS in the definition of radiometric and
  geometric standards.
•   The WGCV will encourage traceability to
  international standards.
•  The WGCV will propose joint calibration and
  validation campaigns to CEOS Members and will
  seek CEOS support for these campaigns.
•   The WGCV will cooperate with other CEOS
  Working Groups to focus efforts and to ensure the
  best use of resources.
•  

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Achievements in 2002-2003
Working Group on Calibration Validation

• Completion New CEOS WGCV Website
  http//www.wgcvceos.org/
• Complete archive for WGCV and subgroups
• Info on workshop events
• Preparation and distribution of WGCV Newsletter
  issue 10 summarizing last three years
  achievements
• Preparation of WGCV/WGISS demo at CEOS Plenary
• WGCV contribution to CEOS Newsletter 20,21 and
  CEOS Annual Report 2001-2002

CEOS plenary to note continuous effort to promote
the WGCVs and its subgroups activities with a
focus on benefits and achievements
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Achievements in 2003
Working Group on Calibration Validation

• WGCV Plenary 20th hosted by CSIRO in Hobart,
  Australia
• from 12th to 14th February 2003
• Candidature of Dr Jeff Morissette NASA for LPV
  Chair approved
• Special Sessions on Australian activities
• Progress on priority actions defined in CEOS 5
  years plan for implementation in WGCV workplan
• Liaison with WGISS implementation Cal/Val Test
  Facility phase 1
• Liaison with ISPRS preparation of joint
  Workshop on geometric and Radiometric Standards

CEOS Plenary is invited to endorse the
appointment of new chair of the LPV subgroup Dr
Jeff Morissette NASA
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Achievements in 2003
Working Group on Calibration Validation

• WGCV Plenary 21st hosted by CSSAR CAS
  ,Beijing,China
• from 15th to 17th October 2003
• Candidature of Dr Stephen Ungar NASA/NOAA for
  WGCV Chair approved unanimously at WGCV 21 and
  submitted to CEOS Plenary
• Special session on Chinese activities
• Workplan issue 3.2 prepared in response to the
  priority actions given by CEOS plenary in CEOS 5
  years plan (action 16-04 CEOS plenary 16)
• Completion of Phase I of the joint WGCV / WGISS
  activity on CEOS core test sites and preparation
  of demo at CEOS plenary.
• Requirements for Phase 2 for the WTF expressed by
  three WGCV subgroups
• WGCV / ISPRS taskforce on radiometric and
  geometric standards kick-off and workshop planned
  for 5th December 2003 NASA Stennis, Mississippi
  USA

• CEOS Plenary is invited
• To endorse the Work Plan 2003 2006 (Issue 3.2)
  prepared by WGCV

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CEOS Plenary is invited 2. To approve the
proposed nomination for WGCV chair of Dr Stephen
UNGAR from NASA
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CEOS WGCV Subgroup highlights in 2003
Working Group on Calibration Validation

• Atmospheric Chemistry subgroups chair
  involvement in IGOS-IGACO theme report (November
  2003)
• IGACO report recommendation on calibration/validat
  ion
• AC subgroup success in securing funds to conduct
  intercomparisons amongst network ozone ground
  stations
• AC subgroup concern that arctic ground
  stations used for cal/val are
  closing e.g coverage of the Eureka
  Astro station for stratospheric ozone
• SAR subgroup joint workshop hosted by CSA in June
  2003(120 participants-99 presentations)
• SAR subgroup advances in calibration/validation
  on PolarimetricInterferometric SARs

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CEOS WGCV Subgroup highlights in 2003
Working Group on Calibration Validation

• Preparation SAR subgroup workshop by ESA in
  conjunction with EUSAR 2004 Ulm Germany May
  27-28, announcement and call for papers
• Land product validation subgroup involvment in
  IGOS (Carbon theme) and GOFC/GOLD active fire
  validation with ASTER
• Land Product Validation subgroups preparation of
  a special issue in IEEE/TGARS describing state of
  the art research on both protocol and results for
  validation and accuracy assessment of global land
  products
•     

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CEOS WGCV highlights in 2003
Working Group on Calibration Validation

• Microwave Sensors subgroups significant progress
  on terminology document (to be completed early
  2004) and advances in the calibration of
  interferometric radiometers
• Infrared and Visible Optical Sensors subgroup
  study to characterise on-board solar diffusers
• Terrain Mapping subgroups significant progress
  on SRTM DEM validation

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CEOS WGCV Recommendations
Working Group on Calibration Validation

• Recommendation 1
• Since satellite operators and data providers
  globally use varying solar irradiance profiles
  for the derivation of radiances and reflectances,
  
• WGCV recommends for consistency, to converge to
  the recently refined solar reference spectrum by
  G. Thuillier and encourages its use at the
  highest possible spectral resolution.
• The source spectrum will be provided also
  through the WGCV website, with pointers to
  different instrument (resampled) spectra
• (Reference The Solar Spectral Irradiance from
  200 to 2400 nm as Measured by the SOLSPEC
  Spectrometer from the Atlas and Eureca Missions,
  Solar Physics 214(1) 1-22 May 2003, by G.
  Thuillier M. Hersé D. Labs T. Foujols W.
  Peetermans D. Gillotay P.C. Simon H. Mandel).
• WGCV further recommends that instrument teams
  should post the exo-atmospheric solar irradiances
  they use, together with processing/resampling
  information, in a band-integrated form on the www
  (single spectrum recommended).

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CEOS WGCV Recommendations
Working Group on Calibration Validation

• Recommendation 2
• Considering the experience with current
  satellite sensors and the preliminary study
  carried out by a Standard Laboratory for the
  WGCV, the need for testing on board diffusers
  under hard radiation, UV radiation and
  contamination environments is recognised.
• - WGCV recommends to further support the
  in-depth study of the behaviour of satellite
  onboard calibration diffusers and their stability
  in the space environment,

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CEOS WGCV Recommendations
Working Group on Calibration Validation

• Recommendation 3
• The polar regions are most sensitive to, and
  are early indicators of, climate change.
  Atmospheric chemistry observation in these
  regions are needed by the IGOS and satellite
  cal/val.
• The WGCV recommend that CEOS strongly
  encourages that full use of high latitude ground
  stations be maintained or restored to full
  operation.
• This recommendation should be considered by CEOS
  member agencies and passed on to their partner
  national agencies who have the interest and
  resources to implement this recommendation.
•  

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CEOS WGCV Recommendations
Working Group on Calibration Validation

• Recommendation 4
• Noting that the Amazon rainforest has been well
  studied and is currently the best natural target
  for SAR calibration.
• Statistical evaluation of the Amazon rainforest
  SAR data sets acquired for more than five years
  shows that C and L band SAR data (ERS-2
  Scatterometer data for AMI, Radarsat SAR, JERS-1
  SAR) are ultimately stable with the absolute
  backscattering coefficients (sigma-naught or
  gamma-naught), which vary with frequency,
  polarization, and incidence angle (for
  sigma-naught and not for gamma-naught), and
  standard deviation of less than 0.3 dB, which
  includes diurnal and seasonal variation (WGCV SAR
  subgroups 11th workshop report to be published
  Dec 2003).
• The WGCV recommends that the Amazon rainforest
  area be used as one of the calibration transfer
  standards. The Amazon rainforest must be
  regularly measured to maintain its traceability
  to the internationally agreed standards.

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CEOS WGCV Recommendations
Working Group on Calibration Validation

• Recommendation 6
• WGCV recognises the significant improvements
  in spaceborne DEM quality over pre-existing DEM
  products currently used in satellite data
  processing systems.
• WGCV recommends use of newly available
  spaceborne DEMs, where available and suitably
  validated, to replace existing coarse data-sets
  for processing land and atmospheric data-sets at
  the earliest opportunity.

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END
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Draft Letter for the NRSCC Chair To all members
and associate members of CEOS I am forwarding the
following six recommendations made by the CEOS
Working Group on Calibration and Validation
(WGCV) to you for implementation. These
recommendations were unanimously adopted at the
17th CEOS Plenary Meeting on November 20, 2003.
Implementation of these recommendations is
essential to the effective realization of a
global observing system.
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WGCalVal Recommendations Approved at CEOS Plenary
17 1. WGCV recommends for consistency, to
converge to the recently refined solar reference
spectrum by G. Thuillier and encourages its use
at the highest possible spectral resolution. 2.
WGCV further recommends that instrument teams
should post the exo-atmospheric solar irradiances
they use, together with processing/resampling
information, in a band-integrated form on the www
(single spectrum recommended). 3. WGCV recommends
to further support the in-depth study of the
behaviour of satellite onboard calibration
diffusers and their stability in the space
environment,
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WGCalVal Recommendations Approved at CEOS Plenary
17 4. WGCV recommends that CEOS strongly
encourages that full use of high latitude ground
stations be maintained or restored to full
operation. 5. WGCV recommends that the Amazon
rainforest area be used as one of the calibration
transfer standards. The Amazon rainforest must
be regularly measured to maintain its
traceability to the internationally agreed
standards. 6. WGCV recommends use of newly
available spaceborne DEMs, where available and
suitably validated, to replace existing coarse
data-sets for processing land and atmospheric
data-sets at the earliest opportunity.
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CEOS 2003 Annual Report It is our pleasure to
bring you this 2003 Annual Report, which
describes these and other CEOS activities and
accomplishments. As always, for more detailed
information and copies of any CEOS documents and
report, please visit the CEOS homepage at
www.ceos.org or contact our regional Secretariat
representative(s). Ghassem R. Asrar Professor
Xu Guanhua Associate Administrator Minister for
Earth Science Ministry of Science and
Technology National Aeronautics and Peoples
Republic of China Space Administration Member
of Chinese Academy of Science CEOS Chairman
2004 .
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Working Group on Calibration and Validation The
objective of the Working Group on Calibration and
Validation (WGCV) is to ensure long-term
confidence in the accuracy and quality of Earth
observation data and products. WGCV has two
specific tasks 1) sensor-specific calibration
and validation (where calibration is defined as
the process of quantitatively defining the
system response to known, controlled signal
inputs, and validation as the process of
assessing by independent means the quality of the
data products derived from the system outputs)
and 2) geophysical parameter and derived product
validation. WGCV provides a forum for
calibration and validation information exchange,
coordination and cooperative activities. WGCV
promotes the exchange of technical information
and documentation, joint experiments, and the
sharing of facilities, expertise and resources
among its members as appropriate. WGCV also seeks
to be the recognized first point-of-contact for
the international user community as far as
calibration and validation information is
concerned.
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Working Group on Calibration and
Validation Highlights of the WGCV activities in
2003 include Completion of Phase I of the
joint WGCV / WGISS activity on CEOS core
text sites and preparation of demo at CEOS
plenary. WGCV / ISPRS taskforce on radiometric
and geometric standards kick-off and workshop.
Atmospheric Chemistry subgroups success in
securing funds to conduct intercomparisons
amongst network ozone ground stations AC
subgroup concern that arctic ground stations used
for cal/val are closing. SAR subgroup advances
in calibration/validation on Polarimetric- Interfe
rometric SARs. Land Product Validation
subgroups preparation of a special issue
in IEEE/TGARS describing state of the art
research on both protocal and results for
validation and accurancy assessment of global
land products. Microwave Sensors subgroups
significant progress on terminology document and
advances in the calibration of interferometric
radiometers. Infrared and Visible Optical
Sensors subgroup study to characterize
on-board solar diffusers. Terrain Mapping
subgroups significant progress on SRTM DEM
validation. New WGCV web site completion.
WGCV Newsletter preparation and publication.