Data Description:

Data are NCEP values of globally integrated torques, for friction
torque (in file ftorque.ncep.reanalysis), mountain torque (in file
mtorque.ncep.reanalysis) and gravity wave torque (in file
gtorque.ncep.reanalysis).

Mountain torque depends on the normal pressure gradient across
topography multiplied by d, the distance to the reference axis.
Friction torque is the tangential force against the surface multiplied
by d.  Gravity wave drag is a modelled force that simulates the impact
of friction over topography on smaller scales than those resolved by
the model grid.  The gravity wave torque is thus gravity wave drag
multiplied by d.

This data was calculated from NCEP/NCAR reanalyses by Dr. Klaus
Weickmann of the NOAA Climate Diagnostics Center in Boulder, CO.  Data
are averaged to once daily from four-times daily, and each epoch
consists of a record giving the date, time, and the torque value.
Units are kg m**2 s**-2

Each days data may be read with the following FORTRAN code:

      read(lunit,101) iyear, imonth, iday, ihour, torque
 101  format(4i4,e15.7)


For more information abot the NCEP/NCAR reanalysis project, consult
the following:

Kalnay, E., et al., 1996: The NCEP/NCAR 40-year reanalysis
project. Bull. Amer. Meteor. Soc., 77, 437-471.