SGP/SMOS/E4 - 6-month Calibration Checks

During the time periods specified, the SMOS.E4 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.

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

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

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

SGP/SMOS/E4 - Wind Monitor 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)

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

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

SGP/SMOS/E4 - 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.

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

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

SGP/SMOS/E4 - Missing data

Data are missing and unrecoverable

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

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

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