SGP/SWATS/E8 - Sensor failure, 15cm W

The temperature rise readings from the 15-cm depth on the west profile are incorrect. This 
also causes the matric potential and water content data to be incorrect.

Instrument removed from service 20091110.

• Volumetric Water Content, West Profile(watcont_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)

SGP/SWATS/E1 - Sensor failure, 85cm W

The 85-west sensor failed and began reporting missing values (-9999) with intermittent 
incorrect values.

Instrument removed from service 20091014.

• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)
• Volumetric Water Content, West Profile(watcont_W)
• Soil Temperature, West Profile(tsoil_W)

SGP/SWATS/E5 - Sensor failure, 25cm E

The 25-cm East sensor began reporting missing values (-9999) after 0130 GMT, with 
intermittent incorrect values.  All data from this sensor are missing or incorrect. 

Instrument removed from service 20091102.

• Soil Water Potential, East Profile(soilwatpot_E)
• Volumetric Water Content, East Profile(watcont_E)
• Sensor Temperature Rise, East Profile(trise_E)
• Soil Temperature, East Profile(tsoil_E)

SGP/SWATS/E1 - Sensor failure, 25cm E

The soil sensor at the 25-cm depth on the East profile began reporting missing or 
incorrect values for all soil moisture measurements (trise, tsoil, soilwatpot, watcont).

Instrument removed from service 20091014.

• Volumetric Water Content, East Profile(watcont_E)
• Soil Temperature, East Profile(tsoil_E)
• Sensor Temperature Rise, East Profile(trise_E)
• Soil Water Potential, East Profile(soilwatpot_E)

SGP/SWATS/E1 - Sensor failure, 5cm E

Both trise and tsoil for the 5cm E sensor began to drop out intermittently reporting both 
incorrect values and values of -9999 starting on 08/18/2007.  Since this date, there have 
been periods where values of -9999 have been reported continuously for months at a time, 
but the sensor always seems to come back eventually and report values that appear 
correct.  

Currently, this sensor is reporting normal values again but has failed as recently as 
10/08/08.  When this sensor is failing, it typically impacts tsoil_E, trise_E, soilwatpot_E, 
and watcont_E.  However, there are cases where tsoil_E appears OK while the other 
variables are incorrect.

Instrument was removed from service 20091014.

• Volumetric Water Content, East Profile(watcont_E)
• Soil Temperature, East Profile(tsoil_E)
• Sensor Temperature Rise, East Profile(trise_E)
• Soil Water Potential, East Profile(soilwatpot_E)

SGP/SWATS/E8 - Sensor failure, 35cm W

The sensor installed at 35 cm at the west profile has produced questionable data ince it 
was installed back in 1996.  Once the sensor began to stabilize at 17:00 GMT on 07/20/99, 
it has produced questionable or incorrect values of temperature rise.  From 07/20/99 to 
the present date, 35cm W temperature rise values have stayed within a range of 
approximately 0.8-2.0 C, while the sensor from the 35cm E profile has produced an approximate range 
of 1.5-4.0 C.

In addition, the calibration for this sensor is so bad it is not possible to correct it 
using field data.  The range of temperature rise values produced by this sensor is too 
limited to reliably re-calibrate the instrument.  Under the old ARM calibration for SWATS, 
the calibrated reference temperature change should fall within a range of 1.45-4.00 C (the 
new range is 1.38-3.96 C).  For this sensor, the reference temperature change has fallen 
within an approximate range of 0.2-1.7 C and the calibration is actually adjusting the 
trise measurements in the wrong direction.  

Therefore, all temperature rise, matric potential and water content data 
are all highly suspect from the 35cm W sensor.

The soil temperature data appear to be OK.

Instrument removed from service 20091110.

• Volumetric Water Content, West Profile(watcont_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)

SGP/SWATS/E27 - Sensor failure, 85cm W

The 85 cm West sensor (based on location in the multiplexer) at this facility appears to 
have failed.  After initially demonstrating problems in mid-2006, all variables from this 
sensor began to report as -9999 on and after 7:00 GMT on 08/04/06.  

Note, although this sensor is listed as 85 cm W in the data files due to its location in 
the multiplexer, it is actually the 85 cm E sensor in the ground.  

Instrument removed from service 20091204.

• Soil Temperature, West Profile(tsoil_W)
• Soil Water Potential, West Profile(soilwatpot_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Volumetric Water Content, West Profile(watcont_W)

SGP/SWATS/E1 - Sensor failure, 85cm E

Both trise and tsoil for the 85cm E sensor dropped out reporting values of -9999 starting 
on 08/24/2005.  Interestingly, both this sensor and the one at 85 cm W (D040730.1) began 
to report data again June-August 2006.  Both sensors have reported values of -9999 after 
this brief period through the current date.  This problem impacts tsoil_E, trise_E, 
soilwatpot_E, and watcont_E. 

Instrument was removed from service 20091014.

• Volumetric Water Content, East Profile(watcont_E)
• Soil Temperature, East Profile(tsoil_E)
• Sensor Temperature Rise, East Profile(trise_E)
• Soil Water Potential, East Profile(soilwatpot_E)

SGP/SWATS/E5 - Sensor failure, 15cm W

Both the temperature rise and soil temperature for the 15-cm W profile began to 
intermittently report as -9999 on 04/08/08. The intermittent drop outs continued until 9:00 GMT on 
04/20/08 after which all data are reported as -9999 through the current date. This 
problem also impacts the matric potential and water content data.

Instrument removed from service 20091102.

• Volumetric Water Content, West Profile(watcont_W)
• Soil Temperature, West Profile(tsoil_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)

SGP/SWATS/E5 - Sensor failure, 125cm W

Both the temperature rise and soil temperature measures of the 125-cm W profile are 
reported as -9999 since 10/07/99. This sensor has been essentially dead since then, and all 
associated variables are impacted. 

Instrument removed from service 20091102.

• Volumetric Water Content, West Profile(watcont_W)
• Soil Temperature, West Profile(tsoil_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)

SGP/SWATS/E5 - Sensor failure, 175cm W

The temperature rise of the 175cm W profile began reporting as incorrect with values near 
0 C on 20010817. This also causes the matric potential and water content data to be 
incorrect.

Soil temperature data are not affected.

Instrument removed from service 20091102.

• Volumetric Water Content, West Profile(watcont_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)

SGP/SWATS/E7 - Soil temperature irregular, 125cm E

The 125 cm E sensor was demonstrating temporal irregularities in its soil temperature 
measurements.  These irregularities consisted of dips and increases of around 2-4 C that 
typically started around 14:00 or 15:00 GMT on most days. On other days the values appeared 
somewhat noisy throughout the day. In both cases, the temporal changes did not compare 
well with the other sensors installed at E7.  

A bad fiber optic cable was replaced.

• Soil Temperature, East Profile(tsoil_E)

SGP/SWATS/E10 - Soil temperature irregular, 25cm W

The 25 cm W sensor was demonstrating temporal irregularities and were noisy at times.  
These irregularities consisted of dips and increases of around 2-4 C that typically started 
around 14:00 or 15:00 GMT on most days. On other days the values appeared somewhat noisy 
throughout the day. In both cases, the temporal changes did not compare well with the 
other sensors installed at E10.

A broken wire was repaired for 25cm W sensor.

• Soil Temperature, West Profile(tsoil_W)

SGP/SWATS/E27 - Incorrect soil temperature measurements

All of the tsoil measurements at this EF appear noisy and erratic at times, impacting all 
sensors and both profiles.

• Soil Temperature, East Profile(tsoil_E)
• Soil Temperature, West Profile(tsoil_W)

SGP/SWATS/E16 - Sensor failure, 125cm E

Temperature rise values from the 125 cm E sensor began to intermittently drop out to 
values near 0 C starting at 4:00 GMT on 12/14 before permanently reporting values near 0 C at 
20:00 GMT on 12/15.  The incorrect values of temperature rise result in incorrect matric 
potential and water content data for these sensors.

Soil temperature for this sensor is not affected.  

Sensor resumed working 20090425.

• Volumetric Water Content, East Profile(watcont_E)
• Soil Water Potential, East Profile(soilwatpot_E)
• Sensor Temperature Rise, East Profile(trise_E)

SGP/SWATS/E1 - Sensor failure, 15cm W

Both trise and tsoil for the 15cm W sensor began to drop out intermittently reporting both 
incorrect values and values of -9999 starting on 05/29/2008.  Currently, this sensor is 
reporting mainly values of -9999 for all measurements with a few random incorrect values 
from time to time.  This problem impacts tsoil_W, trise_W, soilwatpot_W, and watcont_W.

Instrument removed from service 20091014.

• Sensor Temperature Rise, West Profile(trise_W)
• Soil Water Potential, West Profile(soilwatpot_W)
• Volumetric Water Content, West Profile(watcont_W)
• Soil Temperature, West Profile(tsoil_W)

SGP/SWATS/E5 - Sensor failure, 5cm E

Beginning 07/08/2007, the 5-cm East profile sensor is reporting -9999 for all variables.

Instrument removed from service 20091102.

• Soil Water Potential, East Profile(soilwatpot_E)
• Volumetric Water Content, East Profile(watcont_E)
• Sensor Temperature Rise, East Profile(trise_E)
• Soil Temperature, East Profile(tsoil_E)

SGP/SWATS/E19 - Incorrect soil, 35cm E

The tsoil measurements from the 35 cm E sensor at this site are slightly irregular and too 
noisy at times.

• Soil Temperature, East Profile(tsoil_E)

SGP/SWATS/E1 - Instrument failure

The diurnal temperature change in the tsoil measurements from all sensors installed below 
5 cm at this facility appear questionable.  On a daily basis, the diurnal trends in the 
tsoil measurements from depths below 5 cm did not match the above ground tref measurements 
or the tsoil measurements from the 5 cm W sensor (the 5 cm E sensor has failed). The 
tsoil measurements from these deeper sensors began to decrease prior to solar noon nearly 
every day. Also, the magnitudes of the diurnal change in these instruments appear to be the 
same for all sensors (Normally, the diurnal changes in tsoil are damped as we progress 
deeper below the surface).  

Attempts to correct the problem were unsuccessful until the time of site decommissioning.  
This facility was decommissioned and maintenance efforts ceased 10/1/2009.

• Soil Temperature, East Profile(tsoil_E)
• Soil Temperature, West Profile(tsoil_W)

SGP/SWATS/E27 - Sensor failure, 125cm E

The 125 cm E sensor tsoil measurements were very erratic and much too high, and all trise 
values were reporting as slightly negative or -9999.  The issue started on 06/07 and 
corrected itself by 20:00 GMT the same day, but the problem returned on 06/10.  Connections 
were re-seated on 6/17 to resolve the problem.

• Volumetric Water Content, East Profile(watcont_E)
• Soil Temperature, East Profile(tsoil_E)
• serial_numbers_W
• Sensor Temperature Rise, East Profile(trise_E)

SGP/SWATS/E3 - Incorrect temperature rise data

The temperature rise readings from all depths on both the east and west profiles were 
incorrect, reading near zero. This also causes the matric potential and water content data to 
be incorrect.

• Sensor Temperature Rise, East Profile(trise_E)
• Volumetric Water Content, East Profile(watcont_E)
• Soil Temperature, West Profile(tsoil_W)
• Soil Water Potential, West Profile(soilwatpot_W)
• Volumetric Water Content, West Profile(watcont_W)
• Soil Temperature, East Profile(tsoil_E)
• Soil Water Potential, East Profile(soilwatpot_E)
• time_offset
• Sensor Temperature Rise, West Profile(trise_W)
• tref

SGP/SWATS/E8 - Sensor failure, 60cm W

At 2:00 GMT on 07/30 all measurements from the 60 cm W sensor began reporting as -9999. 
The sensor has failed. 

This EF site is scheduled to be decommissioned in the near future.

Instrument removed from service 20091110.

• Volumetric Water Content, West Profile(watcont_W)
• Sensor Temperature Rise, West Profile(trise_W)
• Soil Temperature, West Profile(tsoil_W)
• Soil Water Potential, West Profile(soilwatpot_W)

SGP/SWATS/E19 - Incorrect tsoil, 85cm E and 85cm W

The tsoil measurements from the 85 cm E and 85 cm W sensors at this site are slightly 
irregular and too noisy at times.

• Soil Temperature, East Profile(tsoil_E)
• Soil Temperature, West Profile(tsoil_W)

SGP/SWATS/E19 - Incorrect tsoil, 125cm E

The tsoil measurements from the 125 cm E sensor at this site are slightly irregular and 
too noisy at times.

• Soil Temperature, East Profile(tsoil_E)