Remedy 2: Evaluate quality of NWP and reanalysis fields through comparisons with reference data as a means of establishing direct traceability.

Primary gap remedy type: 
Technical
TRL 6
Proposed remedy description: 

The GRUAN processor developed for GAIA-CLIM offers the means of traceable evaluation of the quality of NWP fields at the GRUAN-site locations. Due to the scarcity of reference measurements for comprehensive evaluation of NWP data, it will be necessary to determine additional ‘near-reference’ measurements for which defensible uncertainty estimates can be provided. It is proposed to extend the assessment of NWP fields using other data of demonstrated quality, such as selected GUAN radiosondes and GNSS radio occultations, in order to sample a larger subspace of NWP regimes. Additionally, NWP and reanalysis systems now make use of ensembles (multiple forecasts to represent error growth from uncertain initial conditions and stochastic physics perturbations). Uncertainties as estimated from ensembles should be evaluated using available NWP minus reference-data differences. It is also desirable to extend the assessment to include atmospheric composition, for which reference composition measurements and their uncertainties are required. 

Relevance: 

NWP and reanalysis fields and products are very widely used for the validation and characterisation of EO data, although associated robust uncertainties are lacking. Traceable uncertainties will engender more confidence from users. 

Measurable outcome of success: 

Published uncertainties should be available for widely used NWP and reanalysis model fields such that the uncertainties and associated correlation structures are traceable to underlying reference data. 

Expected viability for the outcome of success: 
  • High
Scale of work: 
  • Single institution
  • Consortium
Time bound to remedy: 
  • Less than 5 years
Indicative cost estimate (investment): 
  • Low cost (< 1 million)
Indicative cost estimate (exploitation): 
  • No
Potential actors: 
  • EU H2020 funding
  • National Meteorological Services