SGP/SMOS/E3 - 6-month Calibration Checks

During the time periods specified, the SMOS.E3 tower was lowered for 6-month Calibration 
Checks.   During these times wind data are incorrect and temperature and humidity data may 
be incorrect.

Note, exact times when tower was down or maintenance was being performed is sometimes 
unknown.  Users should use the remaining data from these days with caution.

Calibration results are available from the OMIS database at 
    
http://www.ops.sgp.arm.gov:591/smos6cal/default.htm 
To view all 6-month calibration reports leave the date time entry blank.

• Wind Speed (vector averaged)(wspd_va)
• Relative humidity inside the instrument enclosure(rh)
• barometric pressure(bar_pres)
• Vapor Pressure (kiloPascals)(vap_pres)
• Beam 0 Temperature(temp)
• Unit Vector Wind Direction(wdir)
• Mean Wind Speed(wspd)
• Standard Deviation of wind direction(sd_deg)

• Standard Deviation of Barometric Pressure(sd_bar_pres)
• Vapor Pressure (kiloPascals)(vap_pres)
• Unit Vector Wind Direction(wdir)
• Standard Deviation of Vapor Pressure(sd_vap_pres)
• Wind Speed (vector averaged)(wspd_va)
• Standard Deviation of wind direction(sd_deg)
• barometric pressure(bar_pres)
• Mean Wind Speed(wspd)
• Standard Deviation of Wind Speed(sd_wspd)
• Beam 0 Temperature(temp)
• Relative humidity inside the instrument enclosure(rh)
• Standard Deviation of Relative Humidity(sd_rh)
• Standard Deviation of Air Temperature(sd_temp)

• Maximum Vapor Pressure(max_vap_pres)
• Time of Minimum Vapor Pressure(time_min_vap_pres)
• Time of Minimum Barometric Pressure(time_min_bar_pres)
• Time of Maximum Temperature(time_max_temp)
• Time of Maximum Vapor Pressure(time_max_vap_pres)
• maximum wind speed (gusts)(max_wspd)
• Minimum of Wind speed(min_wspd)
• Time of Maximum Wind Speed(time_max_wspd)
• Minimum Temperature(min_temp)
• Maximum Barometric Pressure(max_bar_pres)
• Time of Maximum Barometric Pressure(time_max_bar_pres)
• Minimum Vapor Pressure(min_vap_pres)
• Minimum Barometric Pressure(min_bar_pres)
• Time of Maximum Relative Humidity(time_max_rh)
• Time of Minimum Wind Speed(time_min_wspd)
• Minimum Relative Humidity(min_rh)
• Time of Minimum Relative Humidity(time_min_rh)
• Time of Minimum Temperature(time_min_temp)
• Maximum Relative Humidity(max_rh)
• Maximum Temperature(max_temp)

SGP/SMOS/E3 - RH values above max limit during high humidity situations

RH% values intremittently exceeded maximum allowed during high humidity situations.  
Sensor was replaced.

• Vapor Pressure (kiloPascals)(vap_pres)
• Relative humidity inside the instrument enclosure(rh)

• Vapor Pressure (kiloPascals)(vap_pres)
• Standard Deviation of Vapor Pressure(sd_vap_pres)
• Relative humidity inside the instrument enclosure(rh)
• Standard Deviation of Relative Humidity(sd_rh)

• Maximum Vapor Pressure(max_vap_pres)
• Minimum Vapor Pressure(min_vap_pres)
• Time of Minimum Vapor Pressure(time_min_vap_pres)
• Time of Maximum Vapor Pressure(time_max_vap_pres)
• Time of Maximum Relative Humidity(time_max_rh)
• Minimum Relative Humidity(min_rh)
• Time of Minimum Relative Humidity(time_min_rh)
• Maximum Relative Humidity(max_rh)

SGP/SMOS/E3 - Rainfall Data Suspect

Rainfall during this time period was suspect as the gauge was found plugged on 07/12/2006. 
 Last check of site occurred on 06/28/2006.  Any rainfall data collected, whether the 
data is 0 or other than zero is suspect.

• Hourly precipitation(precip)

• Hourly precipitation(precip)

SGP/SMOS/E3 - Wind Data Incorrect Due to Icing

An ice storm caused the wind data from the RM Young wind sensor to be incorrect.  In many 
instances it was frozen and unmoving, at times it measured values but those are extremely 
suspect.

• Wind Speed (vector averaged)(wspd_va)
• Unit Vector Wind Direction(wdir)
• Mean Wind Speed(wspd)
• Standard Deviation of wind direction(sd_deg)

• Mean Wind Speed(wspd)
• Standard Deviation of Wind Speed(sd_wspd)
• Unit Vector Wind Direction(wdir)
• Wind Speed (vector averaged)(wspd_va)
• Standard Deviation of wind direction(sd_deg)

• maximum wind speed (gusts)(max_wspd)
• Time of Minimum Wind Speed(time_min_wspd)
• Minimum of Wind speed(min_wspd)
• Time of Maximum Wind Speed(time_max_wspd)

SGP/SMOS/E3 - Incorrect Offset for Wind Directon

An incorrect offset of 7 degrees was subtracted from the wind direction to correct for 
misalignment of the towers to true north. The wind direction data may be corrected but the 
vector averaged wind speed cannot. Subsequent audits have highlighted problems with past 
measurements of tower alignments.  All corrections to wind direction are being removed and 
Users are directed to view the Instrument Handbook for a table listing all tower 
alignment deviations from true north.  Users can adjust the data at their discretion.

• Unit Vector Wind Direction(wdir)
• Wind Speed (vector averaged)(wspd_va)

• Wind Speed (vector averaged)(wspd_va)
• Unit Vector Wind Direction(wdir)

SGP/SMOS/E3 - Missing data

Data are missing and unrecoverable

• Wind Speed (vector averaged)(wspd_va)
• lat(lat)
• lon(lon)
• barometric pressure(bar_pres)
• Vapor Pressure (kiloPascals)(vap_pres)
• base time(base_time)
• Standard Deviation of wind direction(sd_deg)
• Hourly precipitation(precip)
• Relative humidity inside the instrument enclosure(rh)
• Dummy altitude for Zeb(alt)
• Time offset of tweaks from base_time(time_offset)
• Beam 0 Temperature(temp)
• Unit Vector Wind Direction(wdir)
• Mean Wind Speed(wspd)

• Standard Deviation of Barometric Pressure(sd_bar_pres)
• Unit Vector Wind Direction(wdir)
• Wind Speed (vector averaged)(wspd_va)
• Batter Voltage(vbat)
• Snow Depth Sensor(snow_sen)
• lat(lat)
• Standard Deviation of wind direction(sd_deg)
• barometric pressure(bar_pres)
• Mean Wind Speed(wspd)
• base time(base_time)
• Standard Deviation of Relative Humidity(sd_rh)
• Standard Deviation of Air Temperature(sd_temp)
• Vapor Pressure (kiloPascals)(vap_pres)
• Standard Deviation of Vapor Pressure(sd_vap_pres)
• Hourly precipitation(precip)
• Snow Depth(snow)
• Standard Deviation of Wind Speed(sd_wspd)
• Beam 0 Temperature(temp)
• Dummy altitude for Zeb(alt)
• Relative humidity inside the instrument enclosure(rh)
• lon(lon)
• Time offset of tweaks from base_time(time_offset)

• Maximum Vapor Pressure(max_vap_pres)
• Time of Minimum Vapor Pressure(time_min_vap_pres)
• Time of Maximum Temperature(time_max_temp)
• Time offset of tweaks from base_time(time_offset)
• maximum wind speed (gusts)(max_wspd)
• lat(lat)
• Maximum Snow Depth(max_snow)
• Minimum of Wind speed(min_wspd)
• Minimum Temperature(min_temp)
• Time of Maximum Barometric Pressure(time_max_bar_pres)
• Time of Minimum Snow Depth(time_min_snow)
• Minimum Vapor Pressure(min_vap_pres)
• Minimum Barometric Pressure(min_bar_pres)
• Minimum Relative Humidity(min_rh)
• Time of Minimum Relative Humidity(time_min_rh)
• Maximum Relative Humidity(max_rh)
• Time of Minimum Barometric Pressure(time_min_bar_pres)
• Time of Maximum Vapor Pressure(time_max_vap_pres)
• Minimum Snow Depth(min_snow_depth)
• Time of Maximum Wind Speed(time_max_wspd)
• Maximum Barometric Pressure(max_bar_pres)
• time(time)
• Dummy altitude for Zeb(alt)
• Time of Maximum Snow Depth(time_max_snow)
• lon(lon)
• base time(base_time)
• Time of Maximum Relative Humidity(time_max_rh)
• Time of Minimum Wind Speed(time_min_wspd)
• Time of Minimum Temperature(time_min_temp)
• Maximum Temperature(max_temp)