SGP/SMOS/E6 - 6-month Calibration Checks

During the time periods specified, the SMOS.E6 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.

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

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

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

SGP/SMOS/E6 - 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)