Several people contributed to this implementation to resolve many elements that were needed. Michel Desgagné, Vivian Lee, and Michel Valin contributed to the development and optimization of the tangent-linear and adjoint models, and also to the design of the complex launching scripts of the 4DVAR. We also acknowledge the significant contribution from the Data Assimilation Development Section of the Meteorological Service of Canada (MSC) who have addressed all the observation processing elements, including reception, monitoring, and archiving. The contributions of Gilles Verner, José Garcia, Lorraine Veillette, Réal Sarrazin, Jacques Hallé, Pierre Koclas, Nicolas Wagneur, Nils Ek, and Judy St. James have been particularly important. MSC also provided technical support for the implementation. At the final stages, the operational forecasters provided valuable feedback that helped us iron out some remaining glitches. Their subjective evaluation helped us to ensure that all aspects of the analyses and forecasts used by operations were indeed meeting or exceeding their expectations. We would like to acknowledge particularly the involvement of Alan Rahill and Suzanne Roy. Comments on the manuscript by Erik Andersson, Stephen Cohn, and an anonymous reviewer are also acknowledged.
The operational 4DVAR of MSC uses the M1QN3 minimization code provided to us by Jean-Charles Gilbert of the Institut National de Recherche en Informatique et en Automatique (INRIA).
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