NSA/METTWR/C1 - All 10m level Data Missing

After prolonged power outage and many power spikes during the outage all data from the 10m 
level are missing.  Blown fuse on the power supply was replaced once the temperatures 
warmed enough to allow the lowering of the tower carriages.

• 10m Average Calculated Dew Point(DP10M_AVG)
• 10m Average QLI Reference Temperature(RefT10m_AVG)
• Standard Deviation of 10m Calculated Vapor Pressure(VP10M_STD)
• 10m Average Relative Humidity(RH10M_AVG)
• 10m Vector Averaged Wind Speed(WS10M_U_WVT)
• 10m Average Calculated Vapor Pressure(VP10M_AVG)
• 10m Average QLI Input Voltage(Volt10M_AVG)
• Standard Deviation of 10m Vector Averaged Wind Direction(WD10M_SDU_WVT)
• 10m Average Temperature(T10M_AVG)
• Standard Deviation of 10m Relative Humidity(RH10M_STD)
• 10m Arithmetic Mean Wind Speed(WS10M_S_WVT)
• 10m Vector Averaged Wind Direction(WD10M_DU_WVT)
• Standard Deviation of 10m Calculated Dew Point(DP10M_STD)
• Standard Deviation of 10m Temperature(T10M_STD)

SGP/AOS/C1 - Failed RH sensor

The RH sensor inside the humidified nephelometer began to slowly decline in value in the 
upper RH range beginning in early 2004 and becoming more noticable poor on 20041117. The 
sensor currently reaches a high RH value of about 60% when the actual RH is closer to 80%.

The sensor was replaced in the Spring of 2005, but the problem remained.  Effective 
1/1/2004, this sensor is not used to calculate scientific data and is therefore essentially 
abandoned in the field.  An end-date of 20050501 is being used as a placeholder.

• TSI High RH Neph. relative humidity(TSINephRHSamp_HRH)

SGP/AOS/C1 - wet nephelometer out of service

The humidified nephelometer was removed and shipped back to CMDL to test and work on the 
relative humidity sensor inside the instrument.

• TSI High RH Neph. 700 nm total scat. coef. at 1 um(RedTScatCoef_1um_HRH)
• TSI High RH Neph. 450 nm backscat. coef. at 1 um(BluBScatCoef_1um_HRH)
• TSI High RH Neph. 550 nm total scat. coef. at 10 um(GrnTScatCoef_10um_HRH)
• TSI High RH Neph. 450 nm total scat. coef. at 10 um(BluTScatCoef_10um_HRH)
• Temp. downstream of humidograph(HGdownstream_T)
• TSI High RH Neph. Pressure(TSINephPres_HRH)
• TSI High RH Neph. 450 nm total scat. coef. at 1 um(BluTScatCoef_1um_HRH)
• TSI High RH Neph. Sample Temperature(TSINephTSamp_HRH)
• TSI High RH Neph. 700 nm backscat. coef. at 10 um(RedBScatCoef_10um_HRH)
• RH upstream of humidograph(HGupstream_RH)
• TSI High RH Neph. relative humidity(TSINephRHSamp_HRH)
• TSI High RH Neph. 700 nm backscat. coef. at 1 um(RedBScatCoef_1um_HRH)
• Temp. upstream of humidograph(HGupstream_T)
• TSI High RH Neph. 550 nm backscat. coef. at 1 um(GrnBScatCoef_1um_HRH)
• RH downstream of humidograph(HGdownstream_RH)
• TSI High RH Neph. 550 nm backscat. coef. at 10 um(GrnBScatCoef_10um_HRH)
• TSI High RH Neph. inlet temperature(TSINephTin_HRH)
• TSI High RH Neph. 550 nm total scat. coef. at 1 um(GrnTScatCoef_1um_HRH)
• TSI High RH Neph. 700 nm total scat. coef. at 10 um(RedTScatCoef_10um_HRH)
• TSI High RH Neph. 450 nm backscat. coef. at 10 um(BluBScatCoef_10um_HRH)

NSA/METTWR/C1 - Incorrect Maximum for Precip Values

The max values for cumulative rain sum of 99 mm and the rain rate of 999 mm/hr are 
incorrect.  In communication with the manufacturer it has been found that the manual was in 
error.  The actual max values of the cumulative rain sum is 99.99 mm and the rain rate is 
999.99 mm/hr.

• Precipitation Rate(PcpRate)
• Cumulative Water Sum(CumH2O)

NSA/MPL/C1 - Diode failure

On 3/25, the energy monitor on the MPL dropped from 11 microjoules per second to 2 
microjoules per second.  We determined the problem was the diode; it reached the end of its 
lifetime. A replacement was sent.  Data quality returned to normal.

• Energy output per pulse of transmitted laser beam at 523 nm (Doubled Nd-YLF)(energy_monitor)

• Energy output per pulse of transmitted laser beam at 523 nm (Doubled Nd-YLF)(energy_monitor)
• Aerosol volume backscattering coefficient at 355 nm(backscatter)

TWP/MMCR/C3 - Reprocess: Calibration

The Solaris computer was changed out in late January.  The antenna parameters were not 
changed when this happened so that the SGP's antenna gain and beamwidths were used to 
calculate the radar constant.  This results in an underestimation of 4.69 dB in reflectivity.  

The difference in antenna gain is 57.2-52.73 dB or 4.47 dB.  Since the gain is squared in 
the denominator of the radar constant, this results in an error of 8.94 dB due to the 
antenna gain alone.

The difference in beamwidth is 0.19 to 0.31.  20log(.19/.31) = -4.25 dB.

Total reflectivity error = 8.94 dB - 4.25 dB = 4.69 dB

• MMCR Reflectivity(Reflectivity)

NSA/MWR/C1 - Reprocess: Revised Calibration Coefficients

IN THE BEGINNING (June 1992), the retrieval coefficients used to derive 
the precipitable water vapor (PWV) and liquid water path (LWP) from the 
MWR brightness temperatures were based on the Liebe and Layton (1987) 
water vapor and oxygen absorption model and the Grant (1957) liquid 
water absorption model.

Following the SHEBA experience, revised retrievals based on the more 
recent Rosenkranz (1998) water vapor and oxygen absorption models and 
the Liebe (1991) liquid waer absorption model were developed.  The 
Rosenkranz water vapor absorption model resulted a 2 percent increase 
in PWV relative to the earlier Liebe and Layton model.  The Liebe 
liquid water absorption model decreased the LWP by 10% relative to the 
Grant model.  However, the increased oxygen absorption caused a 
0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly 
significant for low LWP conditions (i.e. thin clouds encountered at 
SHEBA).

Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and 
Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 
22 GHz water vapor line from the HITRAN compilation, which is 5 percent 
smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz 
(1998), provided a better fit to the microwave brightness temperature 
measurements at 5 frequencies in the range 22-30 GHz, and yielded more 
accurate retrievals. Accordingly, revised MWR retrieval coefficients 
have been developed using MONORTM, which utilizes the HITRAN compilation 
for its spectroscopic parameters.  These new retrievals provide 3 
percent less PWV and 2.6 percent greater LWP than the previous 
retrievals based on Rosenkranz (1998).

Although the MWR data will be reprocessed to apply the new monortm-based 
retrievals, for most purposes it will be sufficient to correct the data 
using the following factors:

PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ
LWP_MONORTM = 1.026  * LWP_ROSENKRANZ

The Rosenkranz-based retrieval coefficients became active at NSA.C1 
20020425.1900.  The MONORTM-based retrieval coefficients became active 
at NSA.C1 20050629.0000.

Note: a reprocessing effort is already underway to apply the 
Rosenkranz-based retrieval coefficients to all MWR prior to April 
2002.  An additional reprocessing task will be undertaken to apply 
the MONORTM retrieval to all MWR data when the first is completed. 
Read reprocessing comments in the netcdf file header carefully to 
ensure you are aware which retrieval is in play.

• Mean total water vapor amount along LOS path(vap)
• Mean total liquid water amount along LOS path(liq)

• Mean total water vapor amount along LOS path(vap)
• Mean total liquid water amount along LOS path(liq)

• Ensemble average for MWR vapor in window centered about balloon release(mean_vap_mwr)
• Ensemble average for MWR liquid in window centered about balloon release(mean_liq_mwr)

• Mean total water vapor amount along LOS path(vap)
• Mean total liquid water amount along LOS path(liq)

• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)

NSA/MWR/C2 - Reprocess: Revised Retrieval Coefficients

IN THE BEGINNING (June 1992), the retrieval coefficients used to derive 
the precipitable water vapor (PWV) and liquid water path (LWP) from the 
MWR brightness temperatures were based on the Liebe and Layton (1987) 
water vapor and oxygen absorption model and the Grant (1957) liquid 
water absorption model.

Following the SHEBA experience, revised retrievals based on the more 
recent Rosenkranz (1998) water vapor and oxygen absorption models and 
the Liebe (1991) liquid waer absorption model were developed.  The 
Rosenkranz water vapor absorption model resulted a 2 percent increase 
in PWV relative to the earlier Liebe and Layton model.  The Liebe 
liquid water absorption model decreased the LWP by 10% relative to the 
Grant model.  However, the increased oxygen absorption caused a 
0.02-0.03 mm (20-30 g/m2) reduction in LWP, which was particularly 
significant for low LWP conditions (i.e. thin clouds encountered at 
SHEBA).

Recently, it has been shown (Liljegren, Boukabara, Cady-Pereira, and 
Clough, TGARS v. 43, pp 1102-1108, 2005) that the half-width of the 
22 GHz water vapor line from the HITRAN compilation, which is 5 percent 
smaller than the Liebe and Dillon (1969) half-width used in Rosenkranz 
(1998), provided a better fit to the microwave brightness temperature 
measurements at 5 frequencies in the range 22-30 GHz, and yielded more 
accurate retrievals. Accordingly, revised MWR retrieval coefficients 
have been developed using MONORTM, which utilizes the HITRAN compilation 
for its spectroscopic parameters.  These new retrievals provide 3 
percent less PWV and 2.6 percent greater LWP than the previous 
retrievals based on Rosenkranz (1998).

Although the MWR data will be reprocessed to apply the new monortm-based 
retrievals, for most purposes it will be sufficient to correct the data 
using the following factors:

PWV_MONORTM = 0.9695 * PWV_ROSENKRANZ
LWP_MONORTM = 1.026  * LWP_ROSENKRANZ

The Rosenkranz-based retrieval coefficients became active at NSA.C2 
20020418.1700.  The MONORTM-based retrieval coefficients became active 
at NSA.C2 20050629.0000.

Note: a reprocessing effort is already underway to apply the 
Rosenkranz-based retrieval coefficients to all MWR prior to April 
2002.  An additional reprocessing task will be undertaken to apply 
the MONORTM retrieval to all MWR data when the first is completed. 
Read reprocessing comments in the netcdf file header carefully to 
ensure you are aware which retrieval is in play.

• Mean total liquid water amount along LOS path(liq)
• Mean total water vapor amount along LOS path(vap)

• Mean total liquid water amount along LOS path(liq)
• Mean total water vapor amount along LOS path(vap)

• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)

NSA/MWR/C2 - New software version (4.15) installed

A problem began with the installation of MWR.EXE version 4.12 in September 2002. The 
software had been upgraded from a "DOS" to a "Windows"-compiled program to address an earlier 
problem.  The software upgrade corrected the earlier problem but introduced a new one 
that caused line-of-sight observing cycles to be skipped, a 15% reduction in the number of 
tip curves, and saturation of CPU usage.  Software versions 4.13 and 4.14 also produced 
these problems.

The new MWR software version (4.15) was installed on 9/15/2005. As a consequence of this 
upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to ~50s.

• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• 23.8 GHz sky signal(sky23)
• 23.8 GHz Blackbody signal(bb23)
• Mean 23.8 GHz sky brightness temperature(tbsky23)
• 23.8 GHz blackbody+noise injection signal(bbn23)
• Mean 31.4 GHz sky brightness temperature(tbsky31)
• Mixer kinetic (physical) temperature(tkxc)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• 31.4 GHz blackbody+noise injection signal(bbn31)
• Mean total liquid water amount along LOS path(liq)
• Mean IR brightness temperature(ir_temp)
• Blackbody kinetic temperature(tkbb)
• Mean total water vapor amount along LOS path(vap)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Ambient temperature(tkair)
• Temperature correction coefficient at 31.4 GHz(tc31)
• Temperature correction coefficient at 23.8 GHz(tc23)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• Noise diode mount temperature(tknd)
• 31.4 GHz sky signal(sky31)
• Sky/Cloud Infra-Red Temperature(sky_ir_temp)
• 31.4 GHz Blackbody signal(bb31)

• 23.8 GHz blackbody+noise injection signal(bbn23)
• 31.4 GHz sky signal(tipsky31)
• Noise injection temp at nominal temperature at 31.4 GHz(tnd_nom31)
• Noise injection temp at 31.4 GHz adjusted to tkbb(tnd31)
• Noise injection temp at 31.4 GHz derived from this tip(tnd31I)
• Noise injection temp at 23.8 GHz derived from this tip(tnd23I)
• 31.4 GHz goodness-of-fit coefficient(r31)
• 31.8 GHz sky brightness temperature derived from tip curve(tbskytip31)
• Ambient temperature(tkair)
• 23.8 GHz sky brightness temperature derived from tip curve(tbskytip23)
• Total water vapor along zenith path using tip-derived brightness temperatures(vaptip)
• 23.8 GHz sky signal(tipsky23)
• Mixer kinetic (physical) temperature(tkxc)
• 31.4 GHz blackbody+noise injection signal(bbn31)
• 31.4 GHz Blackbody signal(bb31)
• Noise diode mount temperature(tknd)
• Temperature correction coefficient at 23.8 GHz(tc23)
• 23.8 GHz goodness-of-fit coefficient(r23)
• Blackbody kinetic temperature(tkbb)
• Noise injection temp at nominal temperature at 23.8 GHz(tnd_nom23)
• Noise injection temp at 23.8 GHz adjusted to tkbb(tnd23)
• Total liquid water along zenith path using tip-derived brightness temperatures(liqtip)
• 23.8 GHz Blackbody signal(bb23)
• Temperature correction coefficient at 31.4 GHz(tc31)

NSA/METTWR/C1 - Data 1-minute behind

Data from the Barometer, Chilled Mirror Hygrometer and the Present Weather Sensor were 
one-minute behind due to timing problems collecting data from the Serial Data Multiplexer 
that handled these sensors.

• 15 minute Present Weather Code(PwCod15mi)
• 1 minute Average Visibility(AvgVis1mi)
• Chilled Mirror Dew Point(CMHDP)
• Instant Present Weather Code(InstPwCod)
• Chilled Mirror Calculated Saturation Vapor Pressure(SatVPCMH)
• Chilled Mirror Calculated Relative Humidity(CMHRH)
• Chilled Mirror Calculated Vapor Pressure(VPCMH)
• 1 hour Present Weather Code(PwCod1hr)
• Cumulative Snow Sum(CumSnow)
• 10 minute Average Visibility(AvgVis10m)
• Chilled Mirror Temperature(CMHTemp)
• Precipitation Rate(PcpRate)
• Cumulative Water Sum(CumH2O)
• Present Weather Sensor Alarm(PWSAlarm)
• Atmospheric Pressure(AtmPress)

NSA/METTWR/C1 - Reprocess: Wind direction data incorrect

Wind direction data is off by 30 degrees for all wind sensors.  The 40-m tower was 
misaligned to true north.

• 40m Vector Averaged Wind Direction(WD40M_DU_WVT)
• 2m Vector Averaged Wind Direction(WD2M_DU_WVT)
• 20m Vector Averaged Wind Direction(WD20M_DU_WVT)
• Sonic Vector Averaged Wind Direction(SonicWD_DU_WVT)
• 10m Vector Averaged Wind Direction(WD10M_DU_WVT)

SGP/SURTHREF/C1 - Temperature and RH probe failure

Temperature and RH probe V1 were failing intermittently.

• Vaisala probe 1 RH standard deviation(RH_V1_std)
• Vaisala probe 1 temperature standard deviation(temp_V1_std)
• Vaisala probe 1 temperature maximum(temp_V1_max)
• Vaisala probe 1 temperature minimum(temp_V1_min)
• Vaisala probe 1 RH minimum(RH_V1_min)
• Vaisala probe 1 average temperature(temp_V1_avg)
• Vaisala probe 1 average RH(RH_V1_avg)
• Vaisala probe 1 RH maximum(RH_V1_max)

SGP/EBBR/E8 - metadata corrections

On 20050723, a series of metadata corrections and additions were completed.  These 
metadata changes apply to all EBBR.E8 data collected by ARM back to the installation of the 
instrument in December 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 the systems
3) Correction of soil moisture units (from "by volume" to "gravimetric")

• Time offset from base_time(base_time)

• Time offset from base_time(base_time)

• Time offset from base_time(base_time)

TWP/MMCR/C3 - MMCR Power Monitor failure

During this period, the transmit power monitor on the TWTA was not working.  This resulted 
in the power level reading staying at a steady state (approximately 49 dBm).  Normal 
transmitter fluctuations are expected to be on the order of +/- 0.3 dBm.

• MMCR Reflectivity(Reflectivity)

• Transmitted RF Power(TransmittedRFPower)

NIM/MET/M1 - Software problem

Intermittent Failure of Logger to read data from the Barometer.

• Atmospheric pressure(atmos_pressure)

SGP/ECOR/E10 - Reprocess: Wind Direction Incorrect

It was discovered that the E10 ECOR boom is aligned 17 degrees to the west of true north.  
Therefore, all wind direction data for the stated period is 17 degrees too high.  
Subtract 17 degrees from the wind direction to give the correct direction.

The E10 configuration file was modified to correct this problem.

• vector averaged wind direction(wind_dir)

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.

• Instantaneous Upwelling Longwave Hemispheric Irradiance, Pyrgeometer(inst_up_long_hemisp)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer(up_long_hemisp)

SGP/BRS/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.

• Downwelling Longwave Hemispheric Net Infrared(down_long_netir)
• Upwelling (10 meter) Longwave Hemispheric Irradiance, Ventilated Pyrgeometer(up_long_hemisp)
• Downwelling Longwave Hemispheric Irradiance, Shaded Pyrgeometer(down_long_hemisp_shaded)
• Upwelling Longwave Hemispheric Net Infrared(up_long_netir)

SGP/AOS/C1 - Optical Particle Counter (PCASP-X) down

The AOS Optical Particle Spectrometer (PCASP-X sizing probe) was down during these 
periods.  This lowers the laser reference voltage and results in inaccurate sizing.

• OPC sheath(OPCSheath)
• OPC sample flow(OPCFlow)
• Analog signal from PMS PCASP(OPCLaserVolt)

• PMS PCASP Chan. 7 (0.23 micrometers < Dp < 0.26)(pa23_p26conc)
• PMS PCASP Chan. 26 (3.00 micrometers < Dp < 3.50)(pa300_p350conc)
• PMS PCASP Chan. 28 (4.00 micrometers < Dp < 5.00)(pa400_p500conc)
• PMS PCASP Chan. 15 (0.70 micrometers < Dp < 0.80)(pa70_p80conc)
• PMS PCASP Chan. 25 (2.60 micrometers < Dp < 3.00)(pa260_p300conc)
• PMS PCASP Chan. 0 (Dp > 10 micrometers)(Pa1000Conc)
• PMS PCASP Chan. 2 (0.12 micrometers < Dp < 0.14)(pa12_p14conc)
• PMS PCASP Chan. 30 (6.50 micrometers < Dp < 8.00)(pa650_p800conc)
• PMS PCASP Chan. 6 (0.20 micrometers < Dp < 0.23)(pa20_p23conc)
• PMS PCASP Chan. 19 (1.30 micrometers < Dp < 1.40)(pa130_p140conc)
• PMS PCASP Chan. 17 (0.90 micrometers < Dp < 1.00)(pa90_p100conc)
• PMS PCASP Chan. 18 (1.00 micrometers < Dp < 1.30)(pa100_p130conc)
• PMS PCASP Chan. 3 (0.14 micrometers < Dp < 0.16)(pa14_p16conc)
• PMS PCASP Chan. 31 (8.00 micrometers < Dp < 10.0)(pa800_p1000conc)
• PMS PCASP Chan. 1 1/cm^3 (0.10 micrometers < Dp < 0.12)(pa10_p12conc)
• PMS PCASP Chan. 23 1/cm^3 (2.00 micrometers < Dp < 2.30)(pa200_p230conc)
• PMS PCASP Chan. 24 (2.30 micrometers < Dp < 2.60)(pa230_p260conc)
• PMS PCASP Chan. 21 (1.60 micrometers < Dp < 1.80)(pa160_p180conc)
• PMS PCASP Chan. 22 (1.80 micrometers < Dp < 2.00)(pa180_p200conc)
• PMS PCASP Chan. 9 (0.30 micrometers < Dp < 0.35)(pa30_p35conc)
• PMS PCASP Chan. 27 (3.50 micrometers < Dp < 4.00)(pa350_p400conc)
• PMS PCASP Chan. 13 (0.50 micrometers < Dp < 0.60)(pa50_p60conc)
• PMS PCASP Chan. 4 (0.16 micrometers < Dp < 0.18)(pa16_p18conc)
• PMS PCASP Chan. 20 (1.40 micrometers < Dp < 1.60)(pa140_p160conc)
• PMS PCASP Chan. 8 (0.26 micrometers < Dp < 0.30)(pa26_p30conc)
• PMS PCASP Chan. 5 (0.18 micrometers < Dp < 0.20)(pa18_p20conc)
• PMS PCASP Chan. 14 (0.60 micrometers < Dp < 0.70)(pa60_p70conc)
• PMS PCASP Chan. 10 (0.35 micrometers < Dp < 0.40)(pa35_p40conc)
• PMS PCASP Chan. 11 (0.35 micrometers < Dp < 0.40)(pa40_p45conc)
• PMS PCASP Chan. 16 (0.80 micrometers < Dp < 0.90)(pa80_p90conc)
• PMS PCASP Chan. 12 (0.45 micrometers < Dp < 0.50)(pa45_p50conc)
• PMS PCASP Chan. 29 (5.00 micrometers < Dp < 6.50)(pa500_p650conc)