SGP/EBBR/E13 - Sensible and Latent Heat Fluxes Incorrect (AEM failure)

The AEM was stuck in the home 30 position most of this period.

Therefore, the sensible and latent heat fluxes are incorrect during most of this period.

• temp_air_right
• temp_air_left

• temp_air_top
• temp_air_bottom
• temp_trh_bottom
• vapor_pressure_top
• temp_trh_top
• vapor_pressure_bottom

• bowen_ratio
• Heat flux, sensible, at 1.5-m height, 30-min intervals(sensible_heat_flux)
• temp_trh_top
• rh_bottom_fraction
• vapor_pressure_top
• Heat flux, latent, at 1.5-m height, 30-min intervals(latent_heat_flux)
• vapor_pressure_bottom
• temp_air_bottom
• temp_trh_bottom
• rh_top_fraction
• temp_air_top

SGP/EBBR/E13 - metadata corrections

On 20050723, a series of metadata corrections and additions were completed.  These 
metadata changes apply to all EBBR.E13 data collected by ARM back to the installation of the 
instrument in September 1992.  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 systems
3) Correction of soil type
4) Correction of soil moisture units (from "by volume" to "gravimetric")

• base_time

• base_time

• base_time

SGP/CO2FLX/C1 - downwelling longwave hemispheric irradiance incorrect

A problem was identified with the downwelling longwave hemispheric irradiance (variable 
"r_down_long_hemisp") calibration of our Kipp & Zonen CNR1 radiometer. The offset of the 
instrument is believed to be incorrect over the specified time frame, and a correction of 
the problem is underway.

• Downwelling longwave hemispheric irradiance; t_rad corrected(r_down_long_hemisp)

SGP/CO2FLX/C1 - Soil Temperature measurements

Current data quality check (qc) procedure does not catch spikes in soil temperature 
measurements. A new qc procedure is being tested and will improve the current procedure.

• Average of two upper soil temperature sensors(mean_t_soil_upper)
• Average of two middle soil temperature sensors(mean_t_soil_middle)
• Average of two lower soil temperature sensors(mean_t_soil_lower)

SGP/CO2FLX/C1 - Reprocess: calibration error

A problem was identified with the calibration of the instrument performed on May 27, 2005. 
A study to correct this bad calibration is underway.

• Mean H2O density(mean_q)
• WPL corrected CO2 flux(fc_corr)
• WPL corrected latent heat flux(le)

SGP/IRT/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.

• Radiation, longwave, at 10-m height, upwelling hemispheric irrad., 1-min avg(up_long_hemisp)
• Instantaneous Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(inst_up_long_hemisp)

SGP/CO2FLX/C1 - downwelling longwave hemispheric irradiance incorrect

Downwelling longwave radiation measurements (variable "r_down_long_hemisp") are bad due to 
a wiring issue. Users should not use the downwelling longwave hemispheric irradiance 
during this period. The downwelling shortwave and longwave radiation at CF is also available 
from the Broadband Radiometer Station (BRS).

• Downwelling longwave hemispheric irradiance; t_rad corrected(r_down_long_hemisp)

SGP/CO2FLX/C1 - Reprocess: 4m instruments height

The height of the 4m instruments is 4.8 m and not 4.65 m as shown in b1 datastream

• zm

SGP/CO2FLX/C1 - Reprocessed: Recalibration

The 4m CO2 flux system was calibrated on May 25, 2005. After the calibration was 
performed, calibration coefficients used to measure CO2 density were not updated. This added an 
OFFSET to the CO2 density measurements.

The data have been reprocessed to address the offset.  The reprocessed data were archived 
in December 2008. Please retrieve the updated files for use in your analysis.

• Mean CO2 density(mean_c)