The derivation of the sigma pressure hybrid coordinate semi-Lagrangian model equations for the GFS

"The derivation is based on ECMWF's publications. These detailed notes intend to provide a documentation of what was actually derived and coded into the existing GFS Eulerian over-strucure. The model equations presented in this document are the equations found in Office Note 461 but cast in a Semi-Lagrangian "ready" form"--Page 2. Joseph Sela. "January 2010." "This is an unreviewed manuscript, primarily intended for informal exchange of information among the NCEP staff members." System requirements: Adobe Acrobat Reader. Includes bibliographical references (page 24). 2010 NWS (National Weather Service) NCEP (National Centers for Environmental Prediction) Library Public Domain 2285