TWP/SKYRAD/C1 - PSPs and NIP: Persistent bias

The NIP/Eppley comparison shows that around solar noon,
the NIP is low relative to the Eppleys by about 4% with
this fraction decreasing slowly toward dawn and dusk. 
At very low sun angles, the NIP irradiance exceeds that
from the Eppleys, presumably because of the roll off in
the Eppley's cosine response at those angles.

Larger discrepancies arise between the NIP and and direct
beam calculated from the Eppleys during periods of sun
following rain events. Significant examples of this
phenomenon occurred on October 10 at 02 GMT and 05 GMT
and on October 13 at 20 GMT. In the latter case, the rain
had actually occurred the previous evening.  

We noticed another rain related peculiarity in the NIP
data.  On several occasions, when a rain event followed
a period of full sun, the NIP actually overshot zero and
went negative by about 10 watts (this is an estimated
value only) and persisted for several minutes.  Examples
occurred on October 16, 17, and 31.

In the morning, the sun is apparently blocked by a line
of trees until about 2030 GMT because large but very brief
discrepancies often occur at that time of day.  In the
afternoon, there is often convection over the main part
of Manus Island to the west which blocks the direct beam.

Another likely explanation is dew on the sensors.  I have
requested that the RESET team examine the sensors after
dawn during their next visit (February 1997).  This phenomenon
occurs on November 4, 12, 13, 15, 17, 19, 20, 22, 27, 28, 30.

Throughout the Manus record, there is a distinct tendency
for the sum of the direct plus diffuse SW to be greater than
the corresponding global PSP. The magnitude of the difference
on average fluctuates around 2-3%. There was an increase in
the average percent difference on about 19980509, roughly
corresponding with the reset visit.  However, the daily
average percent differences exhibit a large variability
around this mean, with a range from 0 - 8% for the period
19980509 - 19980731.  Since the beginning of data collection
rarely has the daily average difference been negative. While
differences of a few percent should be expected, I believe
that having these differences always biased warrants closer
scrutiny.  One would typically expect changes in these daily
average differences to be highly correlated with RESET visits,
which is not obvious in the data record, and to randomly switch
sign given a large enough sample size, which we don't have yet.
I recommend that we monitor this to make sure there's not an
unknown SMALL system grounding problem or Campbell logging
program glitch that is causing this bias.

• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

TWP/SKYRAD/C1 - PSP: Removal of shading arm

The shading arm for the SKYRAD shaded PSP was removed while instrument
comparisons were being performed by the ARCS RESET team.

• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

TWP/SKYRAD/C1 - PSPs and NIP: Periods of shortwave radiometer discrepancies

The agreement between the NIP and the direct beam calculated from the
shaded and unshaded PSPs is usually within 5%. However, during these
periods there were larger discrepancies of 5-10%.

• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

TWP/SKYRAD/C1 - PSPs and NIP: Brief discrepancies, unknown cause

Observed anomalously large discrepancies between the NIP and the PSPs.

• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

TWP/SKYRAD/C1 - NIP: Moisture inside NIP

The NIP took on a significant amount of moisture during a rainy period
that ended on 970719.  From this date until the RESET visit in August,
the NIP data is corrupted.  The errors are large (often greater than
100 W/m^2 in the direct beam) in the morning but tend to converge to
the expected values in the afternoon.  In general, NIP data from this
period should be used with extreme caution.

• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)

TWP/SKYRAD/C1 - NIP: Anomalously low values

The NIP appears to be reporting anomalously low values (based on
comparisons with other shortwave instruments).

• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)

TWP/GNDRAD/C1 - GNDRAD radiometer replacement

The GNDRAD radiometers were replaced 10/25/01 from 00:00 to 01:00.

• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Standard
  Deviation(up_long_hemisp_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(up_long_hemisp_max)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Maxima(up_short_hemisp_max)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Standard
  Deviation(up_short_hemisp_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Minima(up_short_hemisp_min)

• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Maxima(up_short_hemisp_max)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer(up_short_hemisp)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(up_long_hemisp_max)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Minima(up_short_hemisp_min)
• Upwelling (10 meter) Shortwave Hemispheric Irradiance, Pyranometer, Standard
  Deviation(up_short_hemisp_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Standard
  Deviation(up_long_hemisp_std)

TWP/C1 - Incorrect elevation reported in Manus Data

(From Bill Clements) We have been using 6m MSL as the station
elevation of Momote (Manus).  This was based on information
posted near the station barometer in the Momote Weather Service
Office.  It turns out that the official WMO station elevation
for Momote is 4m MSL and the upper air elevation is 5m MSL.

All Manus instruments except the sonde station are at 4m MSL.
The sonde launching station is at 5m MSL.

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

• Dummy altitude for Zeb(alt)

TWP/SKYRAD/C1 - IRT affected by rain or shutter

During this time period, the SKYRAD IRT was affected by rain
events.  Water collected on the IRT lens resulting in
elevated and invalid measurement of the sky brightness
temperature.  If the front optic was not dried after a heavy
rain, the data contamination could persist for several days.

The original solution to the problem was to have the local
observers clean the front lens after rains.  In April 1998,
a rain shutter was installed, but it did not become fully 
functional until Aug 9, 1998.

After the rain shutter was installed, the IRT data was
invalid during rain events while the shutter was closed
but ok again immediately after the shutter re-opened.

The configuration of the IRT was changed Oct 19, 2001.
The IRT was mounted such that the field of view is directed
downward at a 30 degree elevation angle and reflected
to the vertical by a front-surfaced, gold-plated mirror.
This configuration prevents rain from directly striking
the lens and collecting in the lens barrel.

Data from 10/96-3/99 were examined and times when the
data are invalid are identified below.  Data from 4/99-10/01
also contain periods of invalid data, but it is left to
the data users to identify those periods and filter the
data according to their needs.

10/12/96 21:00 - 10/14/96 00:00
10/16/96 13:00 - 10/16/96 21:00
10/21/96 04:00 - 10/21/96 23:00
11/09/96 06:00 - 11/09/96 22:00
11/10/96 08:00 - 11/11/96 03:00
11/23/96 17:00 - 11/24/96 03:00
11/25/96 00:00 - 11/25/96 14:00
12/06/96 17:00 - 12/06/96 22:00
12/07/96 01:00 - 12/07/96 06:00
12/11/96 21:00 - 12/11/96 23:00
12/12/96 05:00 - 12/12/96 18:00
12/16/96 03:00 - 12/16/96 23:00
12/19/96 02:00 - 12/20/96 03:00
12/21/96 10:00 - 12/22/96 03:00
12/22/96 20:00 - 12/23/96 07:00
12/27/96 01:00 - 12/27/96 11:00
12/30/96 06:00 - 12/30/96 23:00
01/01/97 21:00 - 01/02/97 01:00
01/10/97 01:00 - 01/10/97 09:00
01/12/97 06:00 - 01/12/97 23:59
01/14/97 01:00 - 01/15/97 23:00
01/17/97 01:00 - 01/17/97 10:00
01/18/97 18:00 - 01/18/97 23:59
01/19/97 17:00 - 01/19/97 23:00
01/20/97 10:00 - 01/21/97 02:00
01/27/97 15:00 - 01/27/97 23:59
01/30/97 16:00 - 01/30/97 23:59
02/01/97 03:00 - 02/01/97 13:00
02/02/97 05:00 - 02/03/97 01:00
02/09/97 00:00 - 02/09/97 03:00
02/10/97 04:00 - 02/11/97 07:00
02/12/97 11:00 - 02/12/97 22:00
02/15/97 00:00 - 02/15/97 03:00
02/16/97 06:00 - 02/16/97 20:00
02/17/97 10:00 - 02/18/97 01:00
02/18/97 04:00 - 02/19/97 23:00
02/24/97 00:00 - 02/24/97 21:00
02/25/97 03:00 - 02/25/97 09:00
02/26/97 01:00 - 02/26/97 07:00
03/01/97 01:00 - 03/01/97 12:00
03/26/97 01:00 - 03/27/97 03:00
04/07/97 13:00 - 04/08/97 02:00
04/11/97 03:00 - 04/11/97 06:00
04/12/97 00:00 - 04/12/97 05:00
04/12/97 12:00 - 04/12/97 18:00
04/15/97 15:00 - 04/15/97 19:00
04/15/97 22:00 - 04/16/97 10:00
04/16/97 12:00 - 04/16/97 23:59
04/22/97 15:00 - 04/22/97 21:00
04/27/97 18:00 - 04/27/97 21:00
04/29/97 13:00 - 04/29/97 20:00
05/01/97 04:00 - 05/01/97 23:00
05/03/97 03:00 - 05/03/97 20:00
05/13/97 13:00 - 05/14/97 23:00
05/16/97 19:00 - 05/16/97 23:59
05/18/97 06:00 - 05/18/97 21:00
05/20/97 02:00 - 05/20/97 21:00
05/22/97 02:00 - 05/22/97 21:00
05/25/97 03:00 - 05/25/97 23:00
05/26/97 04:00 - 05/26/97 11:00
05/27/97 04:00 - 05/27/97 07:00
06/24/97 13:00 - 06/24/97 21:00
06/30/97 19:00 - 07/01/97 06:00
07/04/97 03:00 - 07/04/97 23:59
07/07/97 15:00 - 07/08/97 20:00
07/11/97 13:00 - 07/11/97 21:00
07/12/97 10:00 - 07/12/97 20:00
07/15/97 19:00 - 07/16/97 21:00
07/17/97 18:00 - 07/18/97 05:00
07/18/97 12:00 - 07/19/97 21:00
07/21/97 06:00 - 07/21/97 23:00
08/06/97 21:00 - 08/07/97 07:00
08/07/97 15:00 - 08/07/97 23:00
08/26/97 08:00 - 08/26/97 17:00
09/23/97 20:00 - 09/23/97 21:00
09/25/97 04:00 - 09/25/97 09:00
09/25/97 21:00 - 09/25/97 23:59
10/01/97 03:00 - 10/01/97 06:00
10/12/97 02:00 - 10/12/97 05:00
10/12/97 08:00 - 10/12/97 22:00
10/13/97 06:00 - 10/13/97 17:00
10/22/97 02:00 - 10/22/97 05:00
10/25/97 22:00 - 10/26/97 05:00
10/27/97 07:00 - 10/27/97 23:00
11/02/97 00:00 - 11/02/97 23:59
11/16/97 04:00 - 11/16/97 08:00
11/16/97 18:00 - 11/16/97 22:00
11/18/97 15:00 - 11/18/97 22:00
11/30/97 03:00 - 11/30/97 20:00
12/17/97 18:00 - 12/18/97 23:00
12/21/97 03:00 - 12/21/97 05:00
12/25/97 02:00 - 12/25/97 08:00
12/26/97 18:00 - 12/27/97 01:00
12/28/97 01:00 - 12/28/97 20:00
12/30/97 09:00 - 12/30/97 23:00
01/03/98 04:00 - 01/03/98 05:00
01/04/98 05:00 - 01/05/98 02:00
02/04/98 19:00 - 02/04/98 23:00
02/05/98 04:00 - 02/06/98 19:00
02/07/98 16:00 - 02/08/98 03:00
02/08/98 12:00 - 02/08/98 21:00
02/09/98 06:00 - 02/10/98 04:00
02/20/98 19:00 - 02/20/98 23:59
02/22/98 09:00 - 02/22/98 21:00
03/16/98 00:00 - 03/16/98 02:00
03/17/98 19:00 - 03/17/98 23:59
03/28/98 15:00 - 03/31/98 03:00
03/31/98 10:00 - 03/31/98 22:00
04/01/98 00:00 - 04/01/98 03:18
04/01/98 06:45 - 04/01/98 10:06
04/02/98 00:28 - 04/05/98 03:45
04/05/98 19:25 - 04/05/98 23:54
04/09/98 00:45 - 04/09/98 16:54
04/10/98 15:15 - 04/10/98 19:28
04/11/98 04:24 - 04/11/98 05:34
04/11/98 06:56 - 04/11/98 23:28
04/12/98 00:15 - 04/12/98 01:56
04/12/98 04:15 - 04/12/98 05:37
04/12/98 15:37 - 04/12/98 16:57
04/12/98 17:15 - 04/12/98 21:37
04/13/98 01:37 - 04/13/98 14:45
04/19/98 05:25 - 04/19/98 06:08
04/19/98 20:15 - 04/19/98 22:15
04/21/98 08:57 - 04/22/98 03:45
04/23/98 21:45 - 04/23/98 21:56
04/27/98 17:56 - 04/27/98 22:08
04/28/98 05:45 - 04/28/98 20:36
04/28/98 23:45 - 04/29/98 05:58
04/30/98 10:57 - 04/30/98 21:58
05/01/98 08:08 - 05/02/98 00:08
05/02/98 07:45 - 05/02/98 22:08
05/03/98 08:35 - 05/03/98 22:55
05/04/98 08:16 - 05/04/98 21:55
05/05/98 07:33 - 05/05/98 22:08
05/06/98 07:55 - 05/06/98 22:07
05/07/98 07:55 - 05/07/98 12:33
05/07/98 13:08 - 05/07/98 22:26
05/08/98 02:45 - 05/08/98 03:08
05/08/98 03:34 - 05/08/98 04:16
05/09/98 02:26 - 05/09/98 02:56
05/09/98 20:55 - 05/09/98 21:08
05/09/98 21:45 - 05/09/98 23:35
05/10/98 15:45 - 05/10/98 18:35
05/11/98 22:08 - 05/11/98 22:45
05/12/98 01:34 - 05/12/98 02:26
05/12/98 13:09 - 05/12/98 20:45
05/13/98 00:25 - 05/13/98 04:28
05/13/98 11:15 - 05/13/98 12:57
05/13/98 13:26 - 05/13/98 18:19
05/13/98 19:45 - 05/14/98 22:08
05/16/98 00:15 - 05/16/98 05:15
05/16/98 07:04 - 05/17/98 01:55
05/17/98 05:25 - 05/17/98 06:33
05/19/98 21:16 - 05/19/98 22:16
05/19/98 22:57 - 05/19/98 23:35
05/21/98 16:57 - 05/21/98 21:15
05/21/98 23:56 - 05/22/98 00:45
05/22/98 01:25 - 05/22/98 02:04
05/22/98 19:15 - 05/22/98 21:56
05/23/98 06:25 - 05/23/98 07:07
05/24/98 06:25 - 05/24/98 07:45
05/24/98 10:45 - 05/24/98 21:33
05/25/98 07:57 - 05/25/98 17:26
05/26/98 19:15 - 05/27/98 00:26
05/27/98 04:35 - 05/27/98 12:26
05/29/98 12:05 - 05/29/98 22:15
05/30/98 01:25 - 05/30/98 02:04
06/01/98 15:57 - 06/01/98 21:45
06/02/98 04:15 - 06/02/98 23:34
06/03/98 04:55 - 06/03/98 05:45
06/03/98 07:45 - 06/03/98 11:17
06/03/98 20:58 - 06/03/98 22:58
06/04/98 01:45 - 06/04/98 02:03
06/04/98 07:45 - 06/04/98 09:15
06/04/98 20:29 - 06/04/98 21:15
06/05/98 02:15 - 06/05/98 03:26
06/05/98 05:15 - 06/05/98 13:26
06/05/98 15:26 - 06/06/98 00:05
06/06/98 08:35 - 06/06/98 20:35
06/06/98 21:56 - 06/06/98 22:26
06/07/98 06:45 - 06/07/98 13:45
06/07/98 20:57 - 06/07/98 23:45
06/08/98 00:29 - 06/08/98 01:29
06/08/98 19:29 - 06/08/98 20:58
06/09/98 03:25 - 06/09/98 03:45
06/09/98 06:35 - 06/09/98 06:58
06/09/98 15:42 - 06/09/98 16:58
06/10/98 09:35 - 06/10/98 21:34
06/13/98 02:25 - 06/14/98 03:05
06/13/98 04:45 - 06/13/98 05:26
06/13/98 20:06 - 06/13/98 23:25
06/13/98 23:45 - 06/14/98 00:15
06/14/98 03:25 - 06/14/98 03:45
06/14/98 15:15 - 06/14/98 18:24
06/14/98 20:55 - 06/14/98 21:15
06/16/98 18:34 - 06/16/98 22:36
06/17/98 06:55 - 06/17/98 08:04
06/17/98 09:54 - 06/17/98 10:26
06/18/98 04:26 - 06/18/98 05:05
06/18/98 05:45 - 06/18/98 07:26
06/18/98 12:58 - 06/18/98 13:16
06/18/98 14:15 - 06/18/98 23:56
06/19/98 00:26 - 06/19/98 00:56
06/19/98 02:15 - 06/19/98 03:04
06/19/98 03:25 - 06/19/98 06:56
06/19/98 07:25 - 06/19/98 08:56
06/19/98 11:45 - 06/20/98 13:46
06/20/98 16:29 - 06/20/98 20:45
06/20/98 23:58 - 06/21/98 01:15
06/22/98 03:45 - 06/22/98 04:34
06/22/98 05:45 - 06/22/98 16:34
06/22/98 19:45 - 06/23/98 01:05
06/23/98 02:04 - 06/23/98 02:55
06/23/98 03:45 - 06/23/98 05:05
06/23/98 05:45 - 06/23/98 07:17
06/23/98 22:06 - 06/24/98 16:25
06/24/98 22:36 - 06/24/98 23:25
06/25/98 00:05 - 06/25/98 00:34
06/27/98 00:55 - 06/27/98 01:16
06/27/98 05:45 - 06/27/98 06:05
06/27/98 21:25 - 06/28/98 08:05
06/28/98 12:26 - 06/28/98 13:45
06/30/98 10:58 - 06/30/98 13:05
06/30/98 13:15 - 06/30/98 17:45
06/30/98 18:15 - 06/30/98 21:45
07/01/98 08:26 - 07/01/98 22:05
07/02/98 11:33 - 07/02/98 21:33
07/03/98 17:33 - 07/03/98 21:45
07/04/98 15:57 - 07/04/98 16:45
07/04/98 21:57 - 07/04/98 22:25
07/05/98 07:15 - 07/05/98 22:56
07/05/98 23:05 - 07/06/98 00:05
07/06/98 03:54 - 07/06/98 06:04
07/06/98 07:04 - 07/06/98 10:04
07/06/98 16:45 - 07/06/98 21:15
07/07/98 04:56 - 07/07/98 05:56
07/07/98 06:26 - 07/07/98 06:56
07/07/98 07:45 - 07/07/98 08:34
07/08/98 01:45 - 07/08/98 02:34
07/08/98 02:56 - 07/08/98 03:27
07/08/98 08:26 - 07/08/98 15:08
07/08/98 16:06 - 07/08/98 16:45
07/08/98 17:28 - 07/08/98 19:28
07/09/98 15:55 - 07/09/98 18:03
07/09/98 21:25 - 07/09/98 22:25
07/09/98 23:05 - 07/09/98 23:45
07/10/98 02:25 - 07/10/98 03:58
07/10/98 23:29 - 07/10/98 23:45
07/12/98 09:25 - 07/12/98 09:45
07/12/98 10:25 - 07/12/98 21:15
07/13/98 01:34 - 07/13/98 02:15
07/13/98 04:15 - 07/13/98 04:26
07/13/98 10:15 - 07/13/98 13:57
07/13/98 15:45 - 07/13/98 21:05
07/14/98 02:25 - 07/14/98 02:35
07/14/98 03:15 - 07/14/98 06:25
07/14/98 12:56 - 07/14/98 17:05
07/15/98 03:25 - 07/15/98 05:25
07/15/98 18:15 - 07/15/98 19:55
07/15/98 20:55 - 07/15/98 22:35
07/16/98 03:25 - 07/16/98 06:15
07/16/98 08:35 - 07/16/98 12:15
07/16/98 15:04 - 07/16/98 23:25
07/17/98 10:55 - 07/17/98 13:25
07/19/98 03:35 - 07/19/98 09:15
07/19/98 10:57 - 07/19/98 14:26
07/19/98 15:35 - 07/19/98 18:26
07/19/98 19:55 - 07/19/98 21:15
07/19/98 21:25 - 07/19/98 21:45
07/20/98 01:45 - 07/20/98 02:04
07/20/98 10:15 - 07/20/98 11:45
07/20/98 12:04 - 07/20/98 13:04
07/20/98 16:04 - 07/20/98 22:25
07/20/98 16:05 - 07/20/98 22:25
07/20/98 22:45 - 07/20/98 23:25
07/21/98 01:15 - 07/21/98 01:57
07/21/98 02:34 - 07/21/98 03:45
07/21/98 04:26 - 07/21/98 05:45
07/21/98 06:57 - 07/21/98 07:04
07/21/98 11:45 - 07/21/98 12:35
07/22/98 01:15 - 07/22/98 03:45
07/22/98 05:45 - 07/22/98 22:35
07/22/98 23:35 - 07/23/98 03:15
07/23/98 05:15 - 07/23/98 09:35
07/23/98 17:45 - 07/23/98 19:56
07/23/98 20:45 - 07/23/98 21:56
07/24/98 01:26 - 07/24/98 01:45
07/24/98 04:26 - 07/24/98 04:45
07/24/98 10:15 - 07/24/98 12:15
07/24/98 12:35 - 07/24/98 16:45
07/25/98 07:03 - 07/25/98 13:26
07/26/98 04:25 - 07/26/98 04:45
07/26/98 13:57 - 07/26/98 18:15
07/27/98 09:45 - 07/27/98 09:58
07/27/98 12:05 - 07/28/98 10:25
07/28/98 23:26 - 07/29/98 00:05
07/29/98 00:45 - 07/29/98 01:08
07/29/98 04:58 - 07/29/98 05:26
07/29/98 06:05 - 07/29/98 07:45
07/29/98 16:57 - 07/29/98 18:35
07/30/98 02:45 - 07/30/98 03:45
07/30/98 19:57 - 07/31/98 00:24
07/31/98 07:15 - 07/31/98 08:35
07/31/98 09:04 - 07/31/98 09:45
07/31/98 12:25 - 07/31/98 13:45
08/01/98 00:00 - 08/01/98 00:15
08/01/98 03:15 - 08/01/98 23:05
08/04/98 15:56 - 08/04/98 16:45
08/05/98 06:56 - 08/05/98 07:45
08/06/98 06:45 - 08/06/98 07:15
08/06/98 14:45 - 08/06/98 17:04
08/07/98 05:33 - 08/07/98 07:33
08/09/98 04:15 - 08/09/98 05:33
08/09/98 07:33 - 08/09/98 07:56
08/10/98 19:57 - 08/10/98 21:35
08/11/98 10:04 - 08/11/98 10:15
08/12/98 08:04 - 08/12/98 09:55
08/13/98 16:15 - 08/13/98 16:45
08/14/98 22:04 - 08/14/98 22:15
08/15/98 02:04 - 08/15/98 02:55
08/15/98 04:15 - 08/15/98 04:45
08/15/98 05:25 - 08/15/98 05:45
08/15/98 15:35 - 08/15/98 15:45
08/18/98 07:15 - 08/18/98 07:35
08/18/98 09:15 - 08/18/98 10:27
08/18/98 14:45 - 08/18/98 17:05
08/19/98 15:54 - 08/20/98 10:15
08/27/98 22:10 - 08/28/98 00:45
08/28/98 04:05 - 08/28/98 05:25
09/02/98 05:05 - 09/02/98 05:15
09/03/98 03:15 - 09/03/98 03:25
09/03/98 10:55 - 09/03/98 11:04
09/05/98 20:04 - 09/05/98 21:35
09/07/98 09:45 - 09/07/98 10:05
09/07/98 21:45 - 09/07/98 22:15
09/09/98 05:04 - 09/09/98 06:04
09/09/98 07:35 - 09/09/98 08:45
09/09/98 20:57 - 09/10/98 00:33
09/10/98 06:15 - 09/10/98 07:04
09/10/98 13:55 - 09/10/98 14:24
09/12/98 14:34 - 09/12/98 15:15
09/12/98 17:05 - 09/12/98 17:35
09/13/98 16:55 - 09/13/98 17:04
09/14/98 06:04 - 09/14/98 06:25
09/15/98 08:55 - 09/15/98 09:15
09/15/98 19:45 - 09/15/98 20:55
09/17/98 01:35 - 09/17/98 03:15
09/17/98 08:15 - 09/17/98 09:04
09/17/98 12:55 - 09/17/98 14:04
09/17/98 21:55 - 09/17/98 23:24
09/18/98 11:15 - 09/18/98 12:55
09/18/98 14:45 - 09/18/98 16:55
09/21/98 03:34 - 09/21/98 06:45
09/21/98 15:56 - 09/21/98 16:45
09/21/98 19:04 - 09/22/98 20:55
09/22/98 22:25 - 09/22/98 23:24
09/23/98 03:56 - 09/23/98 05:15
09/23/98 16:04 - 09/23/98 17:15
09/23/98 20:55 - 09/24/98 01:25
09/24/98 02:55 - 09/24/98 03:35
09/24/98 04:25 - 09/24/98 05:56
09/26/98 02:15 - 09/26/98 03:35
09/26/98 08:15 - 09/26/98 08:35
09/26/98 08:45 - 09/26/98 13:24
09/27/98 13:05 - 09/27/98 13:24
09/28/98 03:26 - 09/28/98 03:55
09/29/98 05:45 - 09/29/98 06:15
09/29/98 11:04 - 09/29/98 11:55
09/29/98 19:34 - 09/29/98 21:25
09/30/98 00:05 - 09/30/98 03:15
09/30/98 14:35 - 10/01/98 13:24
10/01/98 14:45 - 10/01/98 16:25
10/02/98 20:45 - 10/02/98 21:35
10/04/98 00:15 - 10/04/98 01:15
10/04/98 02:25 - 10/04/98 08:35
10/05/98 13:15 - 10/05/98 16:57
10/06/98 16:45 - 10/06/98 18:57
10/06/98 21:45 - 10/06/98 22:57
10/08/98 02:15 - 10/08/98 02:45
10/09/98 19:04 - 10/09/98 20:15
10/13/98 01:55 - 10/13/98 03:15
10/15/98 05:55 - 10/15/98 06:35
10/16/98 04:04 - 10/16/98 04:35
10/16/98 22:36 - 10/17/98 00:45
10/17/98 07:24 - 10/17/98 09:15
10/19/98 10:55 - 10/19/98 11:15
10/20/98 03:15 - 10/20/98 04:25
10/23/98 14:45 - 10/23/98 15:15
10/24/98 18:25 - 10/24/98 18:45
10/25/98 00:36 - 10/25/98 00:57
10/25/98 05:15 - 10/25/98 05:24
10/28/98 08:05 - 10/28/98 15:25
10/29/98 06:05 - 10/29/98 06:35
10/29/98 16:15 - 10/29/98 16:55
10/29/98 20:35 - 10/29/98 21:15
10/31/98 11:45 - 10/31/98 15:24
11/01/98 21:35 - 11/01/98 21:45
11/04/98 09:57 - 11/04/98 10:57
11/04/98 11:15 - 11/04/98 12:26
11/05/98 02:34 - 11/05/98 06:00
11/05/98 16:05 - 11/06/98 00:30
11/07/98 11:15 - 11/07/98 11:35
11/07/98 19:24 - 11/07/98 19:57
11/08/98 04:04 - 11/08/98 04:45
11/10/98 02:45 - 11/10/98 03:00
11/10/98 05:00 - 11/10/98 05:30
11/16/98 04:35 - 11/16/98 06:45
11/17/98 01:05 - 11/17/98 06:35
11/17/98 23:24 - 11/18/98 00:45
11/18/98 03:06 - 11/18/98 03:30
11/19/98 00:45 - 11/19/98 01:15
11/19/98 02:04 - 11/19/98 05:36
11/19/98 15:35 - 11/19/98 16:35
11/20/98 00:35 - 11/21/98 01:57
11/21/98 03:24 - 11/21/98 09:05
11/21/98 22:54 - 11/22/98 00:45
11/22/98 23:45 - 11/23/98 02:05
11/23/98 04:54 - 11/23/98 09:00
11/24/98 03:15 - 11/24/98 04:15
11/27/98 07:45 - 11/27/98 08:35
11/28/98 06:24 - 11/28/98 07:15
11/29/98 02:45 - 11/29/98 07:55
11/30/98 20:45 - 11/30/98 21:45
12/01/98 03:35 - 12/01/98 04:15
12/01/98 14:55 - 12/01/98 22:45
12/02/98 02:35 - 12/02/98 13:05
12/02/98 21:15 - 12/02/98 22:15
12/03/98 00:24 - 12/04/98 00:45
12/04/98 06:15 - 12/04/98 06:57
12/04/98 23:55 - 12/05/98 00:45
12/05/98 11:35 - 12/05/98 12:35
12/05/98 16:25 - 12/05/98 17:35
12/05/98 19:15 - 12/06/98 17:35
12/06/98 22:35 - 12/07/98 09:25
12/07/98 12:05 - 12/07/98 13:35
12/07/98 21:45 - 12/08/98 01:15
12/09/98 00:25 - 12/09/98 00:55
12/10/98 02:45 - 12/10/98 04:15
12/11/98 02:55 - 12/11/98 05:36
12/11/98 17:35 - 12/11/98 17:55
12/12/98 00:25 - 12/12/98 17:25
12/12/98 20:05 - 12/12/98 20:56
12/12/98 22:55 - 12/12/98 23:25
12/13/98 00:15 - 12/13/98 00:35
12/13/98 01:35 - 12/13/98 04:25
12/13/98 20:24 - 12/14/98 08:45
12/14/98 14:24 - 12/15/98 21:54
12/17/98 05:35 - 12/17/98 05:45
12/21/98 06:35 - 12/21/98 07:24
12/23/98 17:35 - 12/23/98 18:35
12/24/98 18:25 - 12/24/98 18:45
12/25/98 01:45 - 12/25/98 02:25
12/25/98 04:35 - 12/25/98 14:15
12/25/98 19:15 - 12/25/98 19:55
12/26/98 01:55 - 12/26/98 06:45
12/26/98 17:45 - 12/26/98 18:15
12/27/98 16:15 - 12/27/98 16:35
12/27/98 17:55 - 12/27/98 20:55
12/28/98 13:15 - 12/28/98 13:55
12/28/98 18:15 - 12/28/98 20:55
12/29/98 05:15 - 12/29/98 06:04
12/30/98 03:24 - 12/30/98 05:55
12/30/98 07:15 - 12/30/98 09:15
12/31/98 02:30 - 12/31/98 23:59
01/01/99 00:05 - 01/01/99 01:56
01/01/99 10:15 - 01/01/99 10:45
01/01/99 21:35 - 01/01/99 22:45
01/02/99 00:07 - 01/02/99 00:35
01/02/99 03:35 - 01/02/99 10:25
01/02/99 17:05 - 01/02/99 20:15
01/03/99 08:35 - 01/03/99 08:45
01/03/99 10:24 - 01/03/99 11:04
01/03/99 12:55 - 01/03/99 14:35
01/04/99 13:24 - 01/04/99 13:57
01/05/99 04:45 - 01/05/99 05:05
01/07/99 07:45 - 01/07/99 08:04
01/09/99 21:55 - 01/09/99 22:15
01/10/99 04:15 - 01/10/99 06:35
01/10/99 07:25 - 01/10/99 07:35
01/10/99 08:05 - 01/10/99 08:15
01/15/99 09:15 - 01/15/99 09:24
01/15/99 14:45 - 01/15/99 15:45
01/16/99 04:55 - 01/16/99 06:05
01/18/99 05:55 - 01/18/99 07:15
01/18/99 17:15 - 01/18/99 17:35
01/18/99 20:05 - 01/18/99 20:15
01/19/99 05:03 - 01/19/99 05:15
01/19/99 13:45 - 01/19/99 13:55
01/19/99 15:24 - 01/19/99 15:34
01/19/99 17:05 - 01/19/99 17:45
01/19/99 20:35 - 01/19/99 22:35
01/20/99 03:05 - 01/20/99 03:24
01/20/99 03:55 - 01/20/99 19:45
01/21/99 05:55 - 01/21/99 10:35
01/21/99 14:45 - 01/21/99 17:55
01/21/99 19:35 - 01/21/99 21:15
01/21/99 22:57 - 01/22/99 18:45
01/22/99 22:45 - 01/23/99 00:04
01/23/99 02:24 - 01/23/99 04:45
01/23/99 05:15 - 01/23/99 06:05
01/24/99 13:45 - 01/24/99 15:15
01/25/99 17:24 - 01/25/99 18:24
01/25/99 23:45 - 01/26/99 00:15
01/29/99 22:56 - 01/29/99 23:15
01/30/99 07:04 - 01/30/99 07:45
01/30/99 16:35 - 01/30/99 16:45
01/30/99 19:55 - 01/30/99 23:15
01/31/99 00:55 - 01/31/99 01:35
01/31/99 02:55 - 01/31/99 03:24
01/31/99 06:55 - 01/31/99 08:24
01/31/99 15:55 - 01/31/99 16:15
01/31/99 17:55 - 01/31/99 18:25
01/31/99 21:35 - 02/01/99 05:25
02/01/99 13:15 - 02/01/99 13:55
02/01/99 18:45 - 02/01/99 19:04
02/03/99 03:34 - 02/03/99 04:55
02/03/99 08:24 - 02/03/99 08:45
02/03/99 16:55 - 02/03/99 21:45
02/03/99 23:45 - 02/04/99 03:15
02/04/99 15:15 - 02/04/99 15:24
02/04/99 21:55 - 02/05/99 15:55
02/06/99 14:45 - 02/06/99 15:15
02/07/99 02:15 - 02/07/99 02:35
02/08/99 09:24 - 02/08/99 17:15
02/08/99 22:05 - 02/09/99 13:45
02/09/99 19:05 - 02/09/99 19:35
02/10/99 03:05 - 02/10/99 07:05
02/12/99 00:25 - 02/12/99 04:05
02/13/99 20:55 - 02/14/99 09:15
02/14/99 22:05 - 02/14/99 22:45
02/14/99 23:25 - 02/14/99 23:45
02/15/99 04:55 - 02/15/99 05:25
02/15/99 08:45 - 02/16/99 04:05
02/17/99 15:45 - 02/17/99 16:24
02/18/99 01:05 - 02/18/99 01:15
02/18/99 02:15 - 02/18/99 02:25
02/20/99 06:55 - 02/20/99 07:15
02/20/99 22:55 - 02/20/99 23:25
02/21/99 03:24 - 02/21/99 04:05
02/21/99 15:24 - 02/21/99 17:05
02/21/99 19:05 - 02/21/99 20:24
02/21/99 21:55 - 02/21/99 22:35
02/22/99 00:45 - 02/22/99 01:45
02/22/99 05:55 - 02/22/99 07:15
02/22/99 11:45 - 02/22/99 12:15
02/22/99 13:35 - 02/22/99 13:55
02/22/99 14:24 - 02/22/99 14:45
02/24/99 07:35 - 02/24/99 07:45
02/24/99 16:56 - 02/25/99 05:55
02/25/99 22:45 - 02/25/99 23:55
02/26/99 02:15 - 02/26/99 03:04
02/26/99 04:45 - 02/26/99 05:15
03/01/99 23:45 - 03/02/99 00:55
03/02/99 04:45 - 03/02/99 04:55
03/03/99 01:35 - 03/03/99 02:15
03/03/99 11:35 - 03/03/99 13:15
03/03/99 14:45 - 03/03/99 16:45
03/03/99 21:05 - 03/03/99 21:15
03/05/99 16:45 - 03/05/99 17:05
03/05/99 19:35 - 03/06/99 01:55
03/06/99 10:15 - 03/06/99 10:25
03/06/99 14:24 - 03/06/99 14:45
03/07/99 02:55 - 03/07/99 03:24
03/07/99 03:35 - 03/07/99 05:35
03/07/99 16:45 - 03/07/99 18:45
03/07/99 22:45 - 03/07/99 23:05
03/10/99 00:55 - 03/10/99 01:45
03/10/99 02:35 - 03/10/99 02:55
03/10/99 04:15 - 03/10/99 09:15
03/11/99 02:25 - 03/11/99 02:35
03/12/99 02:25 - 03/12/99 02:35
03/13/99 02:25 - 03/13/99 02:35
03/14/99 02:25 - 03/14/99 02:35
03/15/99 02:25 - 03/15/99 02:35
03/15/99 03:45 - 03/15/99 04:04
03/17/99 13:55 - 03/17/99 14:35
03/17/99 20:15 - 03/17/99 20:35
03/20/99 04:15 - 03/20/99 04:24
03/20/99 05:04 - 03/20/99 05:24
03/20/99 19:45 - 03/20/99 20:25
03/20/99 23:35 - 03/21/99 00:15
03/23/99 10:35 - 03/23/99 11:15
03/25/99 23:15 - 03/25/99 23:55
03/26/99 13:55 - 03/26/99 14:15
03/27/99 18:45 - 03/27/99 20:15
03/28/99 16:15 - 03/28/99 18:06
03/28/99 22:55 - 03/28/99 23:15
03/30/99 02:35 - 03/30/99 02:55
03/31/99 19:45 - 03/31/99 20:35

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)
• Sky Infra-Red Temperature(sky_ir_temp)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

TWP/SKYRAD/C1 - PIR identified as shaded2 is really an unshaded instrument

On Oct 24, 2001, the Global PIR was moved from the unshaded position on the SKYRAD stand 
to a shaded position on the new K&Z tracker.  The data for all time are named "shaded2" 
indicating that this PIR was ALWAYS shaded.  From 19961010 to 20011024, this was not the 
case.

• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_case_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Minima(down_long_hemisp2_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2(down_long_hemisp2)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_dome_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Standard Deviation(down_long_hemisp2_std)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer2(inst_down_long_hemisp2_tp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Maxima(down_long_hemisp2_max)

TWP/SKYRAD/C1  - IRT failure

A moisture related fault was found in the IRT cable after a day of very heavy rain. The 
cable was replaced but the internal power supply was apparently damaged. The instrument was 
replaced with a spare IRT.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)
• Sky Infra-Red Temperature(sky_ir_temp)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

TWP/GNDRAD/C1 - Reprocess: Longwave Calibration error

Modified pyrgeometer calibration procedures were implemented beginning in December 2003.  
These modified procedures introduced a calibration bias in the longwave data.  The 
previous procedures were re-implemented at all sites between December 2005 and February 2006 to 
restore proper calibrations.                                                             
                The data collected while the incorrect procedures were in place are 
being reprocessing to remove the calibration bias.  Note, this also affected standard 
deviation, maximum and minimum data fields.

• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)

TWP/SKYRAD/C1 - Failed PSP ventilator fan

On 1/31 the ventilator for the PSP measuring downwelling_shortwave_hemispheric irradiance 
failed.  The DQ effect of this failure on the measurement of down_short_hemisp is not 
possible to fully quantify but it has been noted that during these failures the PSP 
nighttime values can be several (1-3W/m2) smaller than usual.  Another effect is slower thermal 
response (1hr) of the PSP instrument due to daytime heating and cooling of the ventilator 
housing.

• Instantaneous Downwelling Hemispheric Shortwave, Unshaded Pyranometer Thermopile
  Voltage(inst_global)

• Down-welling unshaded pyranometer voltage(down_short_hemisp)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Standard
  Deviation(down_short_hemisp_std)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Maxima(down_short_hemisp_max)
• Downwelling Shortwave Hemispheric Irradiance, Ventilated Pyranometer, Minima(down_short_hemisp_min)

TWP/SKYRAD/C1 - Tracker Failure

The solar tracker at C1 failed to wake up the morning of 6/10 approximately 2000GMT. Ops 
discovered problem and reset tracker 6/12 approximately 0800GMT.

Tracker dependent instrument data is inaccurate - this includes the short_direct (NIP) and 
down_short_diffuse_hemisp (8-48). The down_short_hemisp (PSP) and down_long_hemisp (PIR) 
are unaffected.

• Instantaneous Direct Normal Shortwave Irradiance, Pyheliometer Thermopile
  Voltage(inst_direct_normal)
• Instantaneous Uncorrected Downwelling Shortwave Diffuse, Shaded Pyranometer
  Thermopile Voltage(inst_diffuse)

• Downwelling Shortwave Hemispheric Irradiance, Pyranometer, Standard Deviation(down_short_diffuse_hemisp_std)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Standard Deviation(short_direct_normal_std)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Maxima(down_short_diffuse_hemisp_max)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer,
  Minima(down_short_diffuse_hemisp_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Maxima(short_direct_normal_max)
• Shortwave Direct Normal Irradiance, Pyrgeometer, Minima(short_direct_normal_min)
• Shortwave Direct Normal Irradiance, Pyrgeometer(short_direct_normal)
• Downwelling Shortwave Diffuse Hemispheric Irradiance, Ventilated Pyranometer(down_short_diffuse_hemisp)

TWP/SKYRAD/C1 - PIR2 ventilator fan failure

During the time range specified the PIR2 output is questionable due to ventilator fan 
failure. Although the PIR is temperature compensated, data review indicates that the PIR2 
didn't compare as well with PIR1. Typical differences during full sun are approximately 10 
w/m2. During this time period differences of 10-14 W/m2 were noted.

• Instantaneous Downwelling Pyrgeometer Case Thermistor Resistance, Pyrgeometer2(inst_down_long_hemisp2_case_resist)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer2(inst_down_long_hemisp2_tp)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Resistance, Pyrgeometer2(inst_down_long_hemisp2_dome_resist)

• Instantaneous Downwelling Pyrgeometer Case Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_case_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Minima(down_long_hemisp2_min)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2(down_long_hemisp2)
• Instantaneous Downwelling Pyrgeometer Dome Thermistor Temperature, Pyrgeometer2(inst_down_long_hemisp2_dome_temp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Standard Deviation(down_long_hemisp2_std)
• Instantaneous Downwelling Pyrgeometer Thermopile, Pyrgeometer2(inst_down_long_hemisp2_tp)
• Downwelling Longwave Hemispheric Irradiance, Pyrgeometer2, Maxima(down_long_hemisp2_max)

TWP/SKYRAD/C1 - IRT measurement error

The IRT was not able to measure sky temperatures below 273.2 K. (This instrument was the 
same one damaged by lightning in November 2005 in Darwin. It was returned for repair in 
April 2006 and again in April 2007 and both times calibrated only down to 0 deg C, so the 
problem was neither detected nor repaired.) The problem was corrected by replacing the IRT.

• Sky Infra Red Temperature Minima(sky_ir_temp_min)
• Sky Infra Red Temperature Maxima(sky_ir_temp_max)
• Sky Infra-Red Temperature(sky_ir_temp)
• Standard Deviation of Sky Infra Red Temperature(sky_ir_temp_std)

TWP/GNDRAD/C1 - IRT power connector

The power connector of the IRT broke due to corrosion. The instrument was replaced.

• Effective Surface (Skin) Temperature(sfc_ir_temp)
• Surface Infra-Red Temperature Maxima(sfc_ir_temp_max)
• Surface Infra-Red Temperature, Standard Deviation(sfc_ir_temp_std)
• Surface Infra-Red Temperature Minima(sfc_ir_temp_min)

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.

"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

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

• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Standard
  Deviation(up_long_hemisp_std)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Maxima(up_long_hemisp_max)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer(up_long_hemisp)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Pyrgeometer, Minima(up_long_hemisp_min)

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