The project aim is to establish and maintain SI traceability of global Fiducial Reference Measurements (FRM) for satellite derived surface temperature product validation.

This will be achieved by:

  • Designing and implementing a laboratory-based comparison of the calibration processes for FRM TIR radiometers (SST, LST, IST and others);
  • Designing and implementing a laboratory-based comparison to verify TIR blackbody sources used to maintain calibration of FRM TIR radiometers;
  • Designing and implementing field inter-comparisons using pairs of FRM TIR radiometers to build a database of knowledge over several years;
  • Conducting field-campaigns for TIR FRM in collaboration with CEOS and the international community;
  • Conducting a full data analysis, derivation and specification of uncertainties;
  • Studying SI Traceability for SST, LST and IST measurements collected using instruments other than FRM TIR radiometers.

The rigorous validation of satellite derived surface temperature measurements through test-sites* enables:

  • Quantification of the performance and validity of the atmospheric correction algorithm used in satellite geophysical parameter retrieval;
  • Monitoring of any specific satellite instrument performance over the mission lifetime;
  • Establishment of independent reference data to bridge the gap between different satellite missions;
  • Development and improvement of satellite retrieval algorithms;
  • Identification of potential means to harmonise observations from different satellites and conceptually different technologies;
  • Further understanding of the air-sea-land-ice interaction and electromagnetic energy emitted from the Earth’s surface.

frm4sts-overview

Key deliverables:

  • Laboratory-based comparison of calibration processes for FRM TIR radiometers (SST, LST, IST);
  • Laboratory-based comparison to verify TIR blackbody sources;
  • Field inter-comparisons of SST using pairs of FRM TIR radiometers on board ships;
  • Field-campaigns for FRM TIR of LST;
  • Best practice protocols for the calibration, operation and performance of FRM of surface temperatures;
  • Full data analysis, derivation and specification of uncertainties, following agreed NMI protocols on all data collected as part of FRM4-CEOS;
  • All outcomes published to promote benefits of Cal/Val;
  • Results of a study of means to establish traceability and potential benefits to satellites validation and CDRs of high accuracy ocean temperature using non-recoverable sensors.

Left: Mobile radiometric measurements across the gravel plains at Gobabeb, Namibia. Middle: Data from the Ship based Sea Surface Temperature Comparisons on the QM2. Right: Ice surface Temperature measurements taking place in Qaanaaq, Greenland.

 

* well-calibrated, SI traceable surface based measurement sites

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