DQRID : D980117.1
Start DateStart TimeEnd DateEnd Time Data Quality Metric
11/01/1997000004/21/20001640Incorrect
more
Subject:
SGP/EBBR/E22 - Reprocess: E22 Soil Moisture Values Off End of Calibration at High Soil 
Moistures
DataStreams:sgp30ebbrE22.b1, sgp15ebbrE22.b1
Description:
Intermittently, since November 1997 soil moisture probes 1, 2, and 3
indicate small positive or else negative values when soil moisture is
high (greater than 35%).  This situation is similar to that at the Cement
EBBR, although the soil at Cordell is not capable of holding as much water
as that at Cement. The cause of the problem is inadequate range in the
calibration curve equation.  Very high soil moisture cannot be obtained
with the calibration soil used by REBS.  The soil moisture equations
could be manipulated to allow larger soil moistures to be calculated.
However, the infrequency of occurence does not justify doing so.

The soil moisture data must be inspected by the data user to see when
soil moisture values for one or more probes is inconsistent with the
others.

Recalculation of ave_shf, e, and h must be made using only the soil
moisture sets with correct soil moisture values.

Affected data values are (# for probe number):

15 minute: rr_sm#

30 minute: sm#, c_shf#, cs#, ces#, g#, ave_shf, e, h

Sensible, latent, and soil heat fluxes can be recalculated using the soil
probe sets that provide correct data.  For example, if soil moisture 2 is
incorrect,

ave_shf = (g1 + g3 + g4 + g5)/4

e = -(q + ave_shf)/(1 +bowen)

h = -(e + ave_shf +q),


If soil moistures 1 and 2 are incorrect,

ave_shf = (g3 + g4 + g5)/3

e = -(q + ave_shf)/(1 +bowen)

h = -(e + ave_shf +q),


If soil moistures 1, 2, and 3 are incorrect,

ave_shf = (g4 + g5)/2

e = -(q + ave_shf)/(1 +bowen)

h = -(e + ave_shf +q),

etc.
Suggestions: 
Measurements:sgp15ebbrE22.b1:
  • soil_moisture_5_r
  • soil_moisture_3_r
  • soil_moisture_4_r
  • soil_moisture_1_r
  • soil_moisture_2_r
more
sgp30ebbrE22.b1:
  • latent_heat_flux
  • energy_storage_change_3
  • energy_storage_change_2
  • energy_storage_change_5
  • energy_storage_change_4
  • energy_storage_change_1
  • soil_heat_capacity_5
  • soil_heat_capacity_4
  • corr_soil_heat_flow_1
  • soil_moisture_4
  • soil_heat_capacity_3
  • soil_moisture_3
  • corr_soil_heat_flow_2
  • soil_heat_capacity_2
  • corr_soil_heat_flow_3
  • sensible_heat_flux
  • soil_moisture_2
  • soil_heat_capacity_1
  • soil_moisture_1
  • corr_soil_heat_flow_4
  • corr_soil_heat_flow_5
  • surface_soil_heat_flux_avg
  • soil_moisture_5
more

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