Fiducial Reference Measurement for Cal/Val

Transcription

1 Fiducial Reference Measurement for Cal/Val Philippe Goryl Sensor Performance Product Algorithm ESA/ESRIN Issue/Revision: 0.0 Reference: Status: ESA UNCLASSIFIED - For Official Use

2 Copernicus European Leadership in EO Slide 2

3 Currently 13 ESA satellites (11 missions) in Phase E 2 new in ESA heritage missions 30+ third party and contributing missions ers-1 ers-2 3 ESA Third Party Missions (landsat, spot, e-pop, gosat, alos, terrasar, etc.) Copernicus Contributing Missions (pleiades, cosmo-skymed, terrasar, deimos, planet, etc.) Slide 3

4 In development 13 ESA missions to be launched before 2024 future of third party & contributing missions altius ers-1 ers-2 3 ee-9 ESA Third Party Missions (landsat, spot, e-pop, gosat, alos, terrasar, etc.) Copernicus Contributing Missions (pleiades, cosmo-skymed, terrasar, deimos, planet, etc.) Slide 4

5 Big Data Revolution ESA EO Data Archive Petabyte Sentinel missions operated by ESA Earth Explorer missions Heritage missions Third Party & Contributing Missions Slide 5

6 Exploring new Horizons New Sentinel Missions (high priority candidates) Anthropogenic Emissions of CO 2 High Res. Land Surface Temperature Polar Ice & Snow Topography Passive Microwave Imaging HyperSpectral Imaging L-band SAR Imaging Innovative Science Missions Biomass P-band SAR FLEX Fluorescence Explorer FORUM or SKIM Slide 6

7 S2A S3A Can we demonstrate we have met requirements? S3C S3D S2B In Europe, we have a lot of Copernicus infrastructure in preparation will we be able demonstrate its S3B performance? Are products fit for purpose within Copernicus? S2C&D Slide 7

8 Calibration / Validation Calibration is the process of quantitatively defining a system s response to known and controlled signal inputs. Validation, on the other hand, is the process of assessing, by independent means, the quality of the data products derived from those system outputs. The Quality Assurance framework for Earth Observation (QA4EO) principles: It is critical that data and derived products are easily accessible in an open manner and have associated with them an indicator of their quality traceable to reference standards (preferably SI) to enable users to assess its suitability for their application i.e. its fitness for purpose. Uncertainties Slide 8

9 Calibration / Validation Calibration and Validation are part of the Space Component Satellite program includes a Cal/Val plan Calibration rely on On-Ground system (vicarious calibration) Validation is based on the synthesis from various input: Generic approach Validation against precise Fiducial Reference Measurements FRM (few points but precise) Validation against in-situ measurements (more points less precise) Validation against others sources (satellite comparison) Validation against Models (data assimilation rejection statistics, integrated model analyses ) Validation using Level 3 data: Statistical comparison between various L-3 from various sensors constitutes an extremely useful tool (mean, median, sd, bias, RMS. for selected zones, transects, latitudinal bands, seasonal trends ) for a cross-validation of the products Validation using monitoring tools (statistic, trend, QC..Etc.) Slide 9

10 Fiducial Reference Measurements The suite of independent ground measurements that provide the maximum Return On Investment (ROI) for a satellite mission by delivering, to users, the required confidence in data products, in the form of independent validation results and satellite measurement uncertainty estimation, over the entire end-to-end duration of a satellite mission. Following the QA4EO principles, the defining mandatory characteristics for FRM are: FRM measurements have documented SI traceability (eg. via round-robin characterisation and regular (pre-and post deployment) calibration of instruments) using metrology standards. FRM measurements are independent from the satellite geophysical retrieval process. An uncertainty budget for all FRM instruments and derived measurements is available and maintained. FRM measurement protocols, procedures and community-wide management practices (measurement, processing, archive, documents etc.) are defined, published openly and adhered to by FRM instrument deployments. FRM are accessible to other researchers allowing independent verification of processing systems. FRM are required to determine the on-orbit uncertainty characteristics of satellite geophysical measurements via independent validation activities. FRM Have an inclusive approach: FRM are not Mission specific (e.g. S3A, B, C, D S2A, B, C, D all need ocean colour FRM, All Altimeters need transponders for range calibration and Sigma0, SST retrievals from selfcalibrating satellite radiometers need validation data) Slide 10

11 Benefit: Confidence in product performance Is a mission product fit for purpose? It depends our knowledge of how good it is High initial investment for FRM: Cannot immediately demonstrate any performance of satellite products Q: What is the optimal FRM investment? Tapered FRM Investment yields significant benefit: Confidence in satellite product performance increases A: Sufficient to show that the Mission meets requirements: A HIGH-IMPACT FRM Further FRM Investment does not yield significant improvement in satellite product quality. Cost benefit optimised Cost: FRM (installation/opera tion/maintenance ) Time Slide 11

12 FRM4 projects A number of projects have been initiated for FRMs qualification. Based on generic model: Laboratory Laboratory Calibration Exercise (LCE) SI traceability Necessary for all participants to assess biases to SI under Laboratory conditions Protocols definition Field campaigns Field Inter- comparison Calibration Exercise (FICE) Analysis Analysis Discussion, Workshop Publications Slide 12

13 ESA pilot projects FRM4 (not exhaustive) Preparing ground truth radiometers and drifting buoy as FRM (SI Traceability) SST, LST Preparing above water radiometers and vicarious infrastructure in Europe for Ocean Colour FRM (SI Traceability) OC Procedures and approached to maintain ground transponders with SI Traceability) Topography The focus of the FRM Ground-Based FTIR Greenhouse Gas Observations (FRM4GHG) project is the intercomparison of instruments and harmonization of products and retrievals from ground based FTIR systems Greenhouse Gas FRM4SAR (web site tbd) The FRM for Ground-Based DOAS Air-Quality Observations (FRM4DOAS) project aims at the harmonization of the retrievals from UV- Visible ground based spectrometers, e.g., MAXDOAS or Pandora, in view of reaching the standards of FRMs for NO2 and ozone. Best practice for deploying an a site (and analysis) for accurate geometric calibration. Slide 13

14 Example (not exhaustive) of supported FRMs used in Sentinel program Sentinel-1 Sentinel-2 Sentinel-3 OPT Sentinel-3 ALT Sentinel- 5P Transponder / Corner Reflectors (Geometry) RadCalNet Buoys (BOUSSOLE) for OC calibration and validation Radiometers for SST Hypernet for Land and water Campaign for Land Campaigns (AMT) Transponder Pandonia MAX-DOAS FTIR Slide 14

15 Concluding remarks Cal/Val is an essential component of a Satellite mission trust, fitness for purpose, interoperability, model, assimilation In situ measurement and data are fundamental for Satellite programmes. Satellite Cal/Val program includes: - Fiducial Reference Measurements (characterisation/traceability) - Networks FRM (RadCalNet, Pandonia) - Networks (Aeronet etc ) - MatchUp Database (MERMAID, EVDC ) - FRM provides the reference/traceability - There is a need to maintain on the long term the infrastructures - FRMs are completed by in situ measurements (provide the number / statistic) - Data policy: In-situ data shall be free and open, but also respecting the data provider intellectual properties. Ex: offering co-authorship in case of publication. - In-situ data shall benefit from open user environment (DIAS, platform). Validation data (in-situ, FRM etc ) shall be part of a collaborative user environment, together with tools allowing exploitation and post-processing of data for specific purpose - International framework is needed - cooperation and collaboration between Partners/Agencies (ESA, EUMETSAT, EEA, EC) but also NASA, NOAA, Australia, DLR, CNES, JAXA, China, UK. CEOS is providing a good frame for coordination. - Analyse/coordinate with EEA to assess the need for situ data (identify priority/gap) Slide 15

16 Thank you for your attention! Issue/Revision: 0.0 Reference: Status: ESA UNCLASSIFIED - For Official Use