Traceability
• Traceability Statement for AIRS/IASI
• Outstanding Issues with Traceability Concept
• How we can strive to resolve these
• Strategy for CLARREO/TRUTHS
Traceability Statement for AIRS/IASI
A key aspect to GSICS is to provide evidence to support applicability of the intercalibration products we develop. A document has been prepared collaboratively by GSICS
partners at EUMETSAT, NOAA, NIST and CNES to provide a statement demonstrating the
suitability of the hyperspectral spectrometers, AIRS and IASI as inter-calibration
references.
This discusses the various pre-flight and in-orbit tests that have been performed on these
instruments. Particular attention is paid to their relative stability, as this is critical if they
are to be used inter-changeably. Various method are described which show that AIRS and
IASI offer consistent radiometric calibration – each with uncertainties ~0.1K (k=1).
The statement also discusses the traceability chain of AIRS and IASI to the SI international
reference standards, which is needed to achieve the long-term goal of GSICS.
From Article for GSICS Quarterly
Statement: https://docs.google.com/document/pub?id=1D97P3NUQewTp-lXPy12tHcV4xOY2-BYOkYc4qr1Jwm8
Slide: 2
31 July 2017
Outstanding Issues with Traceability
• X. Xiong (NASA) to provide Traceability Statement for Aqua/MODIS
• By End 2011 [Action GRWG06_01]
• Need Advice on Application of Traceability Concept to
• Model Results
• Aircraft instruments
• Identify experts in traceability issues
- NIST and NPL
No.
Title
Actionee(s)
Due Date
Action
GRWG06_14
Contact NIST and NPL (Raju Datla and
Nigel Fox) to define a generic way on
how to collaborate on traceability issues
T. Hewison
30 June 2011
• Raise through CEOS/WGCV?
• May need to revise current Traceability Statements…
Slide: 3
31 July 2017
Strategy for CLARREO/TRUTHS
• The US have made the political decision to discontinue the CLARREO concept
– But the CLARREO Science Team is still receiving funding.
• The team is working on a proposal, due on 5 September 2011, to provide a 5
year outlook for a CLARREO-type of instrument on the ISS or an alternative
launch platform.
– It is likely that this will only cover a limited IR range as a proof of concept.
• The next decadal survey (2014) may change the situation,
– as CLARREO is still a highly recommended mission.
• TRUTHS is a similar mission, developed by NPL,
– but not selected yet as a mission on an ESA spacecraft.
• GSICS supports proposals for missions such as CLARREO and TRUTHS to
provide SI-traceable inter-calibration references in orbit, and invites WMO
to communicate this position to the relevant agencies.
Slide: 4
31 July 2017
No.
Title
Actionee(s)
Due Date
Action
GRWG06_15
Provision of a Statement of Support for
TRUTHS by GSICS to Nigel Fox (NPL)
J. Lafeuille
30 June 2011