HFE/ECOR/M1 - Sonic failure

The sonic datastream were "garbled", possibly associated with a serial line damage to the 
LI-7500 serial port or the Versalogic SBC serial port. Garbled data condition existed 
through 10/09/08 0030 GMT followed by missing data through 10/12/08 0230 GMT.

• atm_pres
• rotated variance v(var_rot_v)
• real_lv
• rotated variance w(var_rot_w)
• Pressure, condensation, at altitude, RUC model output(cp)
• rotated variance u(var_rot_u)
• mean_cooler
• alt
• rotated covariance wc(cvar_rot_wc)
• rotated covariance wt(cvar_rot_wt)
• Wind speed(wind_spd)
• real_cp
• Corrected sensible heat flux(h)
• Momentum flux (dynamic)(k)
• real_mr
• n_good_w
• wind_dir
• mean_v
• n_good_v
• mean_w
• n_good_u
• Mean sonic temperature (t), i.e. virtual temperature(mean_t)
• n_good_t
• rotated covariance wq(cvar_rot_wq)
• mean_u
• n_good_q
• Mean H2O density(mean_q)
• kurt_c
• time
• temp_irga
• Mean CO2 density(mean_c)
• lv
• base_time
• covaraince vc(cvar_vc)
• covariance uc(cvar_uc)
• covariance vq(cvar_vq)
• covariance uq(cvar_uq)
• lat
• covariance uv(cvar_uv)
• n_spk_c
• covariance uw(cvar_uw)
• covariance vw(cvar_vw)
• covariance ut(cvar_ut)
• rho
• phi
• covariance vt(cvar_vt)
• standard deviation of wind elevation angle(std_elev)
• covariance wc(cvar_wc)
• real_rho
• Latent heat flux(lv_e)
• n_spk_t
• n_spk_u
• n_spk_v
• n_spk_w
• covariance tc(cvar_tc)
• covaraince wq(cvar_wq)
• n_good_c
• n_spk_q
• covariance tq(cvar_tq)
• n_bad_irga
• covariance wt(cvar_wt)
• n_bad_son_ic
• standard deviation of wind direction(std_wind_dir)
• n_bad_irga_light
• time_offset
• mean_rot_w
• skew_c
• mean_rot_v
• Mean horizontal wind speed(mean_rot_u)
• elev
• skew_w
• skew_u
• mean_spk_c
• skew_v
• friction velocity(ustar)
• mean_spk_q
• skew_t
• skew_q
• n_bad_q
• mean_spk_w
• mean_spk_v
• lon
• mean_spk_u
• mean_spk_t
• n_bad_c
• mr
• rotated covariance vq(cvar_rot_vq)
• rotated covariance vt(cvar_rot_vt)
• n_bad_v
• variance of variable c(var_c)
• n_bad_u
• n_bad_t
• covariance qc(cvar_qc)
• rotated covariance vw(cvar_rot_vw)
• n_bad_w
• kurt_w
• kurt_t
• kurt_u
• kurt_v
• rotated covariance vc(cvar_rot_vc)
• variance of variable q(var_q)
• kurt_q
• variance of variable w(var_w)
• variance of variable v(var_v)
• variance of variable u(var_u)
• variance of variable t(var_t)
• rotated covariance uq(cvar_rot_uq)
• rotated covariance ut(cvar_rot_ut)
• rotated covariance uw(cvar_rot_uw)
• rotated covariance uv(cvar_rot_uv)
• CO2 flux(fc)
• rotated covariance uc(cvar_rot_uc)

HFE/MET/M1 -  Wind Speed data contain offset due to induced voltage

The marine model of the RM Young wind sensor needs twisted pair shielded cable.  The 
manufacturer did not originally supply the pigtail with twisted pair shielded cable.  Use of 
twisted pair shielded cable for the rest of the cable run to the logger was also not 
specified.  This caused an induced voltage in the wind speed line from the wind direction 
excitation.  The induced voltage varied from sensor to sensor and probably changed anytime 
the cable was replaced or parts of the wind sensor were repaired or replaced. The induced 
voltage has been seen to vary from 0.15 m/s to as much as 1.08 m/s.

• wind_spd_arith_max
• Vector-averaged Wind Speed(wind_spd_vec_avg)
• wind_spd_arith_min
• wind_spd_arith_sd
• Wind speed, lower, 1-min avg(wind_spd_arith_avg)

HFE/SKYRAD/M1 - IRT bias

The sky temperatures exhibited a positive bias compared to AERI, especially when < 230K. 
This is indicative of an incorrect emissivity setting (to compensate for the gold mirror) 
or a poor calibration. A similar problem with the same instrument occurred during the FKB 
deployment that was attributed to water vapor.

• sky_ir_temp_min
• Temperature, Sky Infra-Red(sky_ir_temp)
• sky_ir_temp_max

HFE/MET/M1 - Intermittent barometer failure

Intermittent barometer failure occurred throughout the deployment.  We were unable to 
pinpoint the cause of the failure.  Typically one or two minutes of missing data occurred 
every few days.

Since pressure data is typically invariant over 1 minute, linear interpolation should be 
fine to fill in missing data.

• Atmospheric pressure(atmos_pressure)

HFE/MET/M1 - Intermittent PWD data

The Present Weather Detector had intermittent missing values throughout this deployment.  
Missing values occurred almost everyday, usually just one or two minutes per day.

• pwd_cumul_snow
• Average 10 min visibility(pwd_avg_vis_10_min)
• pwd_pw_code_15_min
• pwd_id
• pwd_err_code
• Average 1 min visibility(pwd_avg_vis_1_min)
• pwd_pw_code_1_hr
• pwd_avg_H2O_int_1_min
• pwd_pw_code_inst
• pwd_cumul_water

HFE/MET/M1 - ORG Measuring Ice Crystals or Fog

The ORG was measuring consistent values for long periods of time.  Typically this is 
indicative of fog, ice crystals in the air or poor performance of the lens heaters.

• precip_rate_sd
• Rain, surface, 1-min avg(precip_rate_mean)
• precip_rate_max
• precip_rate_min

HFE/MET/M1 - Induced voltage on wind speed sensor cable

The cable for the wind monitor is not a twisted pair shielded cable.  This caused an 
induced voltage on the wind sensor wires from the wind direction measurement excitation 
voltage.  A small offset is added into the wind speeds.  This value varies.  Most frequently 
the values of 0.49, 0.588 and 0.686 m/s were added into the wind speed.  On 11/27/2008 the 
value jumped to 0.98 m/s for most of the day.

• wind_spd_arith_max
• Vector-averaged Wind Speed(wind_spd_vec_avg)
• wind_spd_arith_min
• wind_spd_arith_sd
• Wind speed, lower, 1-min avg(wind_spd_arith_avg)

HFE/MET/S1 - Barometer missing

All spare barometers and the working barometer for this supplemental site were damaged 
during shipment.  They were sent in for repair and recalibration.

• Atmospheric pressure(atmos_pressure)

HFE/MET/S1 - Optical Rain Gage Failed

All data collected by the ORG is of no use.  The ORG had failed and any data collected was 
not indicative of the current weather.

• precip_rate_max
• precip_rate_sd
• Rain, surface, 1-min avg(precip_rate_mean)
• org_carrier_mean
• precip_rate_min

HFE/MET/S1 - Wind Data Incorrect

The wind sensor became disconnected and no wind speed or direction data were collected.

• wind_dir_sd
• wind_spd_arith_min
• Wind speed, lower, 1-min avg(wind_spd_arith_avg)
• wind_spd_arith_max
• Vector-averaged Wind Speed(wind_spd_vec_avg)
• wind_spd_arith_sd
• Vector-averaged Wind Direction(wind_dir_vec_avg)

HFE/ECOR/M1 - Flux Data Incorrect For Some Wind Directions

For some wind directions the horizontal fetch was not representative of the fields 
surrounding the AMF. Therefore, for the wind direction range 191-349 degrees, the fluxes are 
affected by insufficient fetch, and surfaces, buildings, and vegetation that are not similar 
to the local field conditions.

• Corrected sensible heat flux(h)
• friction velocity(ustar)
• CO2 flux(fc)
• Latent heat flux(lv_e)

HFE/MET/M1 - Reprocess: ORG Data has very small rainrate values

The ORG data is collected via analog signal and not digital.  Therefore, we continuously 
collect data even when no rain is occurring.  We also capture small events such as leaves, 
large bugs, dust, etc blowing through the measurement path.  Because this discrete event 
occurs quickly the value is usually captured for 1 or 2 seconds.  This value is then 
averaged to the minute producing rainrate on the order of .009 mm/hr or less.  

These values are not indicative of rain and should be removed from the record or summing 
over long periods can bias the climate record.  We will reprocess the data to remove these 
small values.

• precip_rate_sd
• Rain, surface, 1-min avg(precip_rate_mean)
• precip_rate_max
• precip_rate_min