TWP/GNDRAD/C1 - Incorrect dome calibration factor

The Manus GNDRAD PIR had an incorrect dome factor since installation.  The
following is an estimate by Chris Cornwall of the magnitude of the effect of
this calibration error. The magnitude of this error is smaller than the
calibration accuracy.

>  I processed the instantaneous data from ARCS2 (10, 30 and 50 
>  seconds after the minute) using 4.32 as the dome factor, and
>  also using 4.00 as the dome factor, as it should have been.
>  The difference between the calculated irradiance results
>  was negligible, as was expected with an instrument operating
>  in the downward-facing direction.
>
>  Over the three days from 11/06/98 to 11/08/98, the error
>  between the two signals averaged 0.09%.  Overnight values
>  were much lower than this, daytime values peaked at 0.42%.
>  The statistics for these error signals were as follows:
>
>  average error 0.000895
>  standard dev  0.001119
>  max error     0.004242
>  min error    -0.00064
>
>  I believe we should change ARCS1 so it is using the correct
>  value for the groundrad pir dome coefficient (4.0 instead of
>  4.32), and we may want to include a DQR stating these findings,
>  although they are much smaller than the overall uncertainty
>  of the PIR itself.

• Instantaneous PIR1 uncorrected irradiance(pir1_voltage)
• Instantaneous PIR1 case thermistor(pir1_case_therm)
• Instantaneous PIR1 dome thermistor(pir1_dome_therm)

• PIR1 unshaded standard deviation(pir1_sd)
• PIR1 unshaded mean(pir1_mean)
• PIR1 unshaded maximum(pir1_max)
• PIR1 unshaded minimum(pir1_min)

• PIR1 unshaded minimum(pir1_min)
• PIR1 unshaded maximum(pir1_max)
• PIR1 unshaded mean(pir1_mean)
• PIR1 unshaded standard deviation(pir1_sd)

• Raw data stream - documentation not supported(Raw data stream - documentation not supported)

• Raw data stream - documentation not supported(Raw data stream - documentation not supported)

TWP/GNDRAD/C1 - Reprocess: IRT calibration

The GNDRAD datalogger configuration for the IRT was changed such that the
calibration factors did not match the output of the IRT.
During the five days or so when the configurations of the data logger and
the IRT did not match, the logger applied the following incorrect scale 
factor and offset to the IRT voltage output:

  (1)  irt(C) = irt(raw)*25 - 50.

It should have used 

  (2)  irt(C) = irt(raw)*60 +  0.

Therefore, data users can correct the values produced by the logger 
(variables irt1_max, irt1_mean, irt1_min), use 

  (3)  irt(C) = irt1*2.4 + 120

• IRT1 minimum(irt1_min)
• IRT1 standard deviation(irt1_sd)
• IRT1 mean(irt1_mean)
• IRT1 maximum(irt1_max)

• Raw data stream - documentation not supported(Raw data stream - documentation not supported)