UERRA is designed to deliver observations and atmospheric data sets of climate quality and to show the quality and uncertainty for climate research and applications in Europe.


There will be several new European reanalysis datasets and the different uncertainty estimates are completely novel. Several methods will be developed and explored. The time period is much longer than before and the horizontal resolution of the analyses is much higher. There are novel ensemble based data assimilation methods that will be developed and proven in UERRA.


The meteorological conditions in Europe over a large part of the preceding decade will be reanalysed from all available observations. Data rescue of observations from manual archives through digitization and quality processing will continue from EURO4M but with emphasis on the sub-daily time scale for reanalysis use. The reanalyses will both be made directly from observations (gridding) or, to a large extent, by assimilating comprehensive sets of many types of observations into meteorological models.


Uncertainties will be estimated in one way from the quality of observations. Most of the model assimilations will be run in ensemble mode and the spread of such reanalyses will provide another measure of uncertainty. The UERRA reanalyses will be made at quite high resolution, from 40 km of ensembles and 20 or 11 km and 5 km for the various model based reanalyses. All data sets can then be compared with independent observations not used e.g. from space or from gridded climate observations and another estimate of uncertainty can be obtained. The reanalyses will also be used in hydrological off-line models and give another independent measure. Statistical modelling and investigations of time and space dependencies will give further insight.


Large data sets of atmospheric and surface variables will be produced, archived and data services will be provided to facilitate a wide use of the products both among scientists and policy makers in the society.


User involvement and evaluation will take place through workshops in the beginning and at the end of the project.