SGP/EBBR/E18 - 6 Month Checks

Many measurements were incorrect while the AEM was positioned with both aspirators at the 
same height for comparison checks.

• rh_bottom_fraction
• vapor_pressure_top
• temp_air_top
• temp_trh_bottom
• temp_trh_top
• rh_top_fraction
• vapor_pressure_bottom
• temp_air_bottom

• rh_top_fraction
• bowen_ratio
• latent_heat_flux
• rh_bottom_fraction
• temp_air_top
• sensible_heat_flux
• temp_air_bottom
• temp_trh_top
• vapor_pressure_bottom
• temp_trh_bottom
• vapor_pressure_top

• temp_air_left
• temp_trh_left_rr
• temp_trh_right_rr
• rh_right_mv
• temp_air_right
• rh_left_mv

SGP/EBBR/E18  - Wind Speed Frozen Stopped By Ice Storm

An ice storm froze the wind speed sensor to a stopped condition.

The wind speed and residual wind speed measurements are incorrect.

This sensor failure does not affect the sensible and latent heat fluxes.

• wspd_arith_mean
• wspd_vec_mean

• wspd_arith_mean
• wspd_vec_mean

• wspd_arith_mean

SGP/EBBR/E18  - Wind Direction Frozen Stopped By Ice Storm

The wind direction sensor was frozen stopped by ice from a storm.  
The wind direction, sigma_wd, and residual wind speed measurements 
are incorrect.

• wdir_vec_mean
• wdir_vec_std
• wspd_vec_mean

• wdir_vec_mean
• wspd_vec_mean
• wdir_vec_std

• wdir_vec_mean_mv

SGP/EBBR/E18 - Improved EBBR CR10 Program

Effective 20050330.0000, the EBBR.E18 CR10 program was revised to improve 
the quality of the primary measurements as follows:
   
1) An RMS procedure is used to determine max and min limits of acceptable
soil heat flow.  This is applied to the individual soil sets.  Measurements
outside the limits are rejected and the measurements within the limits are
used to calculate the average soil heat flow.
   
2) Max and min limits are used to determine incorrect values of net
radiation, sensible heat flux (h), latent heat flux (e), and automatic
exchange mechanism (AEM) signal.  If AEM signal is outside the limits, h 
and e are set to 999s.  If net radiation is outside the limits, h and e are 
set to 999s. If h or e are outside the limits, h and e are set to 999s.
   
Virtually no incorrect soil measurement will affect the primary 
measurements of h and e.
   
By setting h and e to 999s, it can be easily seen that the primary 
variables are incorrect; no other interpretation is possible.
   
Prior to 20050330, the improved CR10 program was NOT in effect.  DQRs have
been submitted for known instances of incorrect soil measurements which
affected the quality of the primary measurements of h and e.
   
Note: the DQR begin date is the begin date of the sgp30ebbrE18.b1 data
stream.  The earlier version of the CR10 program was also used on previous
EBBR datastream names (e.g. sgp30ebbrE18.a1).

• latent_heat_flux
• sensible_heat_flux
• surface_soil_heat_flux_avg

SGP/EBBR/E18 - Net Radiation Incorrect; Sensible and Latent Heat Fluxes Incorrect

The net radiometer top dome was broken and water got inside, making the net radiation, and 
sensible and latent heat flux measurements incorrect.

• net_radiation

• net_radiation
• latent_heat_flux
• sensible_heat_flux

• net_radiation_mv

SGP/EBBR/E18 - Average Soil Heat Flux Incorrect

A typo in the version 9 EBBR program caused average soil heat flow to be zero, resulting 
in both sensible and latent heat fluxes being approximately 20 watts per meter squared too 
large during the middle of the day.

• latent_heat_flux
• sensible_heat_flux
• surface_soil_heat_flux_avg

SGP/EBBR/E18 - metadata corrections

On 20050723, a series of metadata corrections and additions were completed.  These 
metadata changes apply to all EBBR.E18 data collected by ARM back to the installation of the 
instrument in July 1997. Please see the current metadata for correct information.  These 
changes do not affect data values or quality.	

The changes are summarized below:
1) Update of "sensor location" information
2) Addition of installation dates for the systems
3) Correction of soil type
4) Correction of soil moisture units (from "by volume" to "gravimetric")

• base time(base_time)

• base time(base_time)

• base time(base_time)

SGP/EBBR/E18 - Wind Speed Zero

Wind Speed was zero, presumably because the sensor was frozen stopped during freezing 
rain.

• wspd_arith_mean
• wspd_vec_mean

• wspd_arith_mean
• wspd_vec_mean

• wspd_arith_mean

SGP/EBBR/E18 - Sensible and Latent Heat Fluxes and Net Radiation Incorrect

The net radiometer dome was cracked and water had gotten in, resulting in incorrect net 
radiation measurements and therefore incorrect sensible and latent heat flux measurements.

• net_radiation

• net_radiation
• latent_heat_flux
• sensible_heat_flux

• net_radiation_mv

SGP/EBBR/E18 - Sensible and Latent Heat Fluxes Incorrect

Sensible and latent heat fluxes were incorrect during this period because the AEM was not 
exchanging.

• rh_top_fraction
• bowen_ratio
• latent_heat_flux
• rh_bottom_fraction
• temp_trh_top
• temp_air_top
• vapor_pressure_bottom
• sensible_heat_flux
• temp_trh_bottom
• vapor_pressure_top
• temp_air_bottom