| Description: | EDITOR'S NOTE: The earliest portion of the period of time covered
by this DQR occurred prior to the begin date of regular ARM data.
Those data are not readily available from the ARM Archive but are
available by special request. The actual period of time covered
by this DQR is 930401-930824.1530.
Practically all of the information in this DQR is derived from
P930723.1 and C930830.1, both of which were submitted by Dick Hart.
The calibrations initially used for wind speeds on SMOS systems at
Coldwater (E8), Ashton (E9), the central faciality (E13), Ringwood (E15),
and Meeker (E20) were originally "generic"values, but analysis of the
N.I.S.T traceable calibration data reveals that use of these "generic"
calibrations produces data with insufficient accuracy. The calibrations
for the wind speed sensor associated with the instrument must be used
in the datalogger program in order to obtain data with a 1% uncertainty.
For the worst case, one wind speed sensor underestimates the wind speed
by 1.1 m/s at 30 m/s when the "generic" calibration is used. This is
on top of the 1% calibration uncertainty.
No unreported data loss occurred as a result of this calibration question,
but users of the data should adjust the wind speed values before analysis
involving these wind speed values. |