This directory contains data and read programs for PO.DAAC product 008,
Seasat scatterometer global gridded monthly surface wind stress (Chelton).


DATA DESCRIPTION:

  This is one of a series of reprocessed data products that was produced
  from the Seasat-A satellite scatterometer (SASS) data.  Three months of
  vector wind observations are used to construct gridded fields of monthly
  average wind stress over the global oceans.  The procedure used to
  construct these monthly average wind stress fields from SASS data is
  summarized in [Chelton et al., 1990].  The spatial resoultion is 2.5
  degrees in latitude and longitude.  The vector average wind stress are
  stored in dynes per centimeter squared (dyn/cm**2).

  SASS observations of global near-surface winds span the period 7 July
  to 10 October 1978.  The 96-day mission was divided into three periods
  of approximately one-month duration, as indicated in the table below.
  The data files correspond to the three one-month averages and the full
  96-day Seasat mission.

  -------------------------------------------------------------------
                         Calendar dates               Julian days
      Month                  (1978)                     (1978)
  -------------------------------------------------------------------
      July               July 7 - August 6            188 - 218
      August             August 7 - September 6       219 - 249
      September          September 7 - October 10     250 - 283
      July-September     July 7 - October 10          188 - 283


SOFTWARE:

  The data are stored as formatted scaled integers.  Programs to read
  these files are written in Fortran and IDL.  They run on the Silicon
  Graphics but should port easily to other platforms.  The Fortran
  program, read_seasat.f, reads the data and converts the integers to
  real values.  The IDL program, read_vect.pro, also reads the data and
  converts the integers to real values.  This program calls another IDL
  routine, plot_vect.pro, which creates global maps of the vector average
  wind stress fields.


REFERENCE:

  Chelton, D.B., A.M. Mestas-Nunez, and M.H. Freilich, "Global wind stress
  and Sverdrup circulation from the Seasat Scatterometer," Journal of
  Physical Oceanography, 20, 1990, pp. 1175-1205.