1. World Meteorological Organization Working together in weather, climate and water WMO OMM WMO www.wmo.int/sat Draft considerations on calibration and the role of GSICS in the Architecture for Climate Monitoring from Space GSICS-EP-16, item 10 Jérôme Lafeuille (WMO Space Programme

2. WMO OMM Architecture for Climate Monitoring from Space Requested by WMO Congress-16 (2011) Res. 19 (http://www.wmo.int/pages/prog/sat/documents/SAT-GEN_ST-13-Climate-space- monitoring-architecture-Res19-Cg16.pdf ) as an important component of WIGOS (http://www.wmo.int/pages/prog/sat/documents/SAT-GEN_ST-13-Climate-space- monitoring-architecture-Res19-Cg16.pdf The Strategy towards an Architecture for Climate Monitoring from Space is a first step defining a logical framework GSICS-EP-16, Boulder, 15-16 May 2015 Strategy towards an Architecture for Climate Monitoring from Space CEOS, CGMS, WMO

3. Four Pillars of end-to-end Architecture The sensing level (Pillar 1) drives the potential to generate ECVs The actual use of this potential in climate records (Pillar 2) is reflected in the ECV inventory => helps to maximize the use of existing data Calibration activities must be addressed in both Pillars 1 and 2 : – Space segment (pre-launch and on-board calibration, space/ground references) – Data processing CGMS-43, Boulder May 2015

4. Tentative elements of the «first pillar» Implementation principles (best practices) applicable to each satellite programme Seamless continuity and comparability of fundamental data records Measurement consistency through calibration & traceability Community level coordinated planning Maintaining climate monitoring observation requirements Define a reference system that would satisfy the requirements e.g. «CGMS Baseline» or «CEOS Constellation»… Defining the minimum sensor features (spectral, FoV, coverage) which drive the potential performance to support the required CDR Monitoring agencies’ plans to implement the reference system Forward-looking gap analysis to detect potential gaps at the planning phase rather than a posteriori in the ECV records, to support risk reduction measures CGMS-43, Boulder May 2015

5. GSICS in the CGMS Baseline V.Intercalibration Instruments should be intercalibrated on a routine basis against reference instruments or calibration sites. The routine and operational intercalibration and corrections shall be performed in accordance with standards as agreed by the Global Space-based Intercalibration System (GSICS) CGMS-43, Boulder May 2015

6. Proposed sensor calibration items in the Architecture logical framework Calibration infrastructure to be shared a)Ground-based calibration sites b)In-orbit references for traceability c)Databases and software tools Calibration processes to be implemented a)Best practices for pre-launch calibration b)Procedures for in-orbit calibration with uncertainty estimation c)Procedures for in-orbit comparison and inter-calibration d)Procedures for vicarious calibration with ground targets e)Algorithms/tools for re-calibration of archived data f)Communication and capacity building (incl. QA4EO)  These activities fall in the scope of GSICS and CEOS/WGCV CGMS-43, Boulder May 2015

7. Strategy towards an Architecture for Climate Monitoring from Space CGMS-43, Boulder May 2015 Corrected calibration Data acquisition (Level 0) Data sets and tools Intercalibration procedures Observations Environment Operational calibration (Level 1) Intercalibration information Calibration references

8. Calibration function in the architecture for climate monitoring from space and role of GSICS Proposed way forward : Document the role of GSICS in the WIGOS Functional Architecture (in progress) GSICS input on calibration issues in the Vision of WIGOS space component in 2040 (draft) Refine «GSICS User Requirements» of climate applications Work with CEOS/WGCV on joint statement as an input to the Architecture  Guidance welcomed from CGMS CGMS-43, Boulder May 2015