This a longly crafted review paper on the estimation of the innovation-based methods to jointly estimate model and observation error covariance matrices in ensemble data assimilation. It has been heartfully led by our coleague Pierre Tandéo from IMT Atlantique in Brest. It has required almost 3 years, 7 co-authors, 5 reviewers and one very commited and very helpful Editor (David M. Schultz) from the Monthly Weather Review!

The paper, which can be access here, is published in the Monthly Weather Review.