A cheap data assimilation approach for expensive numerical simulations

Using a very cheap Data Assimilation (DA) method, I show an alternative approach to classical DA for numerical climate models which produce a large amount of "big data". The problematic features of state-of-the-art high resolution Regional Climate Models are highlighted. One of the shortcomings is the sensitivity of such models to the slightly different initial and boundary conditions which could be corrected by assimilating scattered observational data. This method might help to reduce the bias of numerical models based on available observations within the model domain, especially for the time-averaged observations and the long-term simulations.