| Description: | On October 25, 1995 the changeout for annual calibration occurred at E4,
Plevna, KS. SEBS unit 8 was removed and unit 12 was installed. Between
1630 and 2130 GMT no data was collected. The soil moisture sensors were
shipped dry from the vendor. Site operations did not realize this and
installed them without wetting the bags that hold the soil moisture sensors
in soil. Site operations did soak the soil after installing the sensors (
as per the procedure). The water did not penetrate into the bags of soil.
Therefore, all soil moisture sensor outputs remained offscale until
October 26. At that point only SM1 came onscale.
This situation continued until 1 November 1995. A couple of days before that
the mentor discovered (in a conversation with the vendor) that the wrong SEBS
unit had been installed. Unit 13 was the unit for which soil specific soil
moisture sensor calibrations had been performed for Plevna; this had not been
made clear either to the mentor or to site operations. On 1 November SEBS
unit 12 was removed from Plevna and SEBS 13 was installed. No data was
collected between 1630 and 2100 GMT.
For SEBS unit 13, SM1, SM3, and SM5 were offscale initially. SM5 came
onscale on 3 November, although the data from it was incorrect until 1900
GMT on 4 November. SM1 and SM3 came onscale on 7 November, went offscale
for a short period on 8 November and stabilized to correct levels at the
beginning of 10 November. All data since then is correct.
Most of the data from the use of SEBS 12 at Plevna is incorrect. It would
be wise to not use it. The incorrect soil moisture after SEBS 13 was
installed affected numerous other data values including:
15 minute: rr_sm1, rr_sm2, rr_sm3, rr_sm4, rr_sm5
30 minute: h, e, ave_shf, shf1, shf2, shf3, shf4, shf5, sm1, sm2, sm3,
sm4, sm5, cs1, cs2, cs3, cs4, cs5, ces1, ces2, ces3, ces4,
g1, g2, g3, g4, g5 |