Understanding Assimilation Systems: How Models Create Their Initial Conditions - version 2

Understanding Assimilation Systems: How Models Create Their Initial Conditions - version 2
July 2014: Version 2 of the NWP course is still valid throughout. The most recent data assimilation system used in NCEP models, the Hybrid-EnKF, is not included. This data assimilation system combines 3D-VAR and EnKF into a single system and gets advantages from both. More discussion of the Hybrid-EnKF system can be found in the GFS May 2012 "splash' announcement at http://www.meted.ucar.edu/nwp/pcu2/GFS_20120522_HybEnKF3DVAR.htm.