The ERA‐Interim reanalysis: configuration and performance of the data assimilation system

Abstract ERA‐Interim is the latest global atmospheric reanalysis produced by the European Centre for Medium‐Range Weather Forecasts (ECMWF). The ERA‐Interim project was conducted in part to prepare for a new atmospheric reanalysis to replace ERA‐40, which will extend back to the early part of the twentieth century. This article describes the forecast model, data assimilation method, and input datasets used to produce ERA‐Interim, and discusses the performance of the system. Special emphasis is placed on various difficulties encountered in the production of ERA‐40, including the representation of the hydrological cycle, the quality of the stratospheric circulation, and the consistency in time of the reanalysed…

• SR
  Sight Research UK

  Awards: ncas10009, NE/F004575/1
• NE
  Natural Environment Research Council

  Awards: ncas10009, NE/F004575/1