With regard to the application of reanalysis data, a comprehensive assessment of the quality of the reanalysis is needed. Therefore, we are continuously developing an evaluation framework that allows a thorough and timely evaluation of reanalysis data with respect to key parameters of interest for climate monitoring and applications, especially in the field of renewable energies.
The focus of the framework is on the utilization of unique independent observations at atmospheric observatories (e.g. JOYCE and DWD Richard Assmann Observatory) or from the full reanalysis domain (e.g. ceilometer network) including an assessment of the marginal as well as the joint distribution of a parameter to assess its specific properties. The evaluation also comprises the comparison with other regional and global reanalyses to assess the performance of our reanalyses and determine the added value compared to existing data sets.
The evaluation does not only focus on averaged deviations, but includes an evaluation of the entire distribution including the extreme value behaviour, the representation of spatial dependencies or the spectral properties of spatio-temporal fields. For this purpose we develop and use advanced statistical methods e.g. based on extreme value theory, copula or Fourier and wavelet spectra.