SGP/MWR/C1 - 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 as follows (BCR 456):
SGP/C1 (Lamont)     4/16/2002, 2000
SGP/B1 (Hillsboro)  4/12/2002, 1600
SGP/B4 (Vici)       4/15/2002, 2300
SGP/B5 (Morris)     4/15/2002, 2300
SGP/B6 (Purcell)    4/16/2002, 2200
SGP/E14(Lamont)     4/16/2002, 0000
NSA/C1 (Barrow)     4/25/2002, 1900 
NSA/C2 (Atqasuk)    4/18/2002, 1700
TWP/C1 (Manus)      5/04/2002, 0200
TWP/C2 (Nauru)      4/27/2002, 0600
TWP/C3 (Darwin)     inception

The MONORTM-based retrieval coefficients became active as follows (BCR 984):

SGP/C1 (Lamont)     6/28/2005, 2300
SGP/B1 (Hillsboro)  6/24/2005, 2100
SGP/B4 (Vici)       6/24/2005, 2100
SGP/B5 (Morris)     6/24/2005, 2100
SGP/B6 (Purcell)    6/24/2005, 1942
SGP/E14(Lamont)     6/28/2005, 2300
NSA/C1 (Barrow)     6/29/2005, 0000 
NSA/C2 (Atqasuk)    6/29/2005, 0000
TWP/C1 (Manus)      6/30/2005, 2100
TWP/C2 (Nauru)      6/30/2005, 2100
TWP/C3 (Darwin)     6/30/2005, 2100
PYE/M1 (Pt. Reyes)  4/08/2005, 1900**

** At Pt. Reyes, the original retrieval coefficients implemented in March 2005 were based 
on a version of the Rosenkranz model that had been modified to use the HITRAN half-width 
at 22 GHz and to be consistent with the water vapor continuum in MONORTM.  These 
retrievals yield nearly identical results to the MONORTM retrievals.  Therefore the Pt. Reyes 
data prior to 4/08/2005 may not require reprocessing.

• Total liquid water along LOS path(liq)
• Total water vapor along LOS path(vap)

• liqtip
• vaptip

• mean_liq_mwr
• mean_vap_mwr

• Total water vapor along LOS path(vap)
• Total liquid water along LOS path(liq)

• Total water vapor along LOS path(vap)
• Total liquid water along LOS path(liq)

• Total water vapor along LOS path(vap)
• Total liquid water along LOS path(liq)

SGP/MWR/C1 - Instrument noise problem

Various variables including the mixer temperatures were very noisy. After several attempts 
to fix the problem, the instrument was taken off line and returned to the manufacturer 
for repair.

• vap_sdev
• Temperature, brightness, longwave(ir_temp)
• number_obs_averaged
• 23tbsky
• liq_sdev
• prob_slope_change
• tbsky23_sdev
• ir_temp_sdev
• water_flag_fraction
• tbsky31_sdev
• Total water vapor along LOS path(vap)
• prob_outlier
• 31tbsky
• water_flag
• prob_level_change
• 23.8 GHz sky brightness temperature(tbsky23)
• Total liquid water along LOS path(liq)
• 31.4 GHz sky brightness temperature(tbsky31)

• tipsky23
• tipsky31
• tnd31I
• r23
• bbn31
• tnd_nom23
• tkair
• tbsky31tip
• tnd23
• tc23
• liqtip
• tnd23I
• tbsky23tip
• tkxc
• tknd
• tkbb
• wet_window
• bb23
• tnd31
• tc31
• vaptip
• bbn23
• r31
• tnd_nom31
• bb31

• 31.4 GHz sky brightness temperature(tbsky31)
• 31tbsky
• dlm_flag_fraction
• 23.8 GHz sky brightness temperature(tbsky23)
• water_flag_periods
• vap_sdev
• Total water vapor along LOS path(vap)
• tbsky31_sdev
• 23tbsky
• Total liquid water along LOS path(liq)
• ir_temp_sdev
• liq_sdev
• tbsky23_sdev
• water_flag_fraction
• Temperature, brightness, longwave(ir_temp)
• dlm_flag_periods

• wet_window
• bbn31
• tkair
• sky23
• tnd23
• tnd31
• tknd
• bbn23
• tkxc
• tnd_nom31
• tc31
• 23.8 GHz sky brightness temperature(tbsky23)
• Total liquid water along LOS path(liq)
• tkbb
• sky31
• tc23
• bb31
• Total water vapor along LOS path(vap)
• bb23
• tnd_nom23
• 31.4 GHz sky brightness temperature(tbsky31)
• Temperature, Sky Infra-Red(sky_ir_temp)

SGP/MWR/C1 - New software version (4.15) installed

A problem began with the installation of MWR.EXE version 4.12 in July 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 08/04/2005. As a consequence of this 
upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to 
~50s.

• tc23
• liqtip
• tnd23I
• tbsky23tip
• tipsky23
• tipsky31
• tkbb
• tknd
• tkxc
• tnd31I
• r23
• bbn31
• tnd_nom23
• bb23
• tkair
• tnd31
• tc31
• vaptip
• tbsky31tip
• bbn23
• r31
• tnd_nom31
• bb31
• tnd23

• bbn23
• tkxc
• tnd_nom31
• 23.8 GHz sky brightness temperature(tbsky23)
• tc31
• Total liquid water along LOS path(liq)
• tkbb
• sky31
• tc23
• bb31
• Total water vapor along LOS path(vap)
• bbn31
• tkair
• bb23
• tnd_nom23
• sky23
• 31.4 GHz sky brightness temperature(tbsky31)
• tnd23
• Temperature, Sky Infra-Red(sky_ir_temp)
• tnd31
• tknd

SGP/ECOR/E14 - CO2/H2O Incorrect

The LI-7500 CO2/H2O sensor stopped working after a rainstorm.  CO2 and H2O data are 
incorrect during the stated period.

• n_bad_irga
• skew_q
• covariance tq(cvar_tq)
• rotated covariance wc(cvar_rot_wc)
• rotated covariance vq(cvar_rot_vq)
• covariance vq(cvar_vq)
• n_spk_c
• temp_irga
• Latent heat flux(lv_e)
• kurt_c
• covariance uc(cvar_uc)
• Mean CO2 density(mean_c)
• variance of variable q(var_q)
• covariance wc(cvar_wc)
• rotated covariance vc(cvar_rot_vc)
• rotated covariance wq(cvar_rot_wq)
• n_good_q
• real_lv
• Mean H2O density(mean_q)
• kurt_q
• covariance uq(cvar_uq)
• mean_spk_c
• variance of variable c(var_c)
• covaraince wq(cvar_wq)
• n_good_c
• rotated covariance uq(cvar_rot_uq)
• n_bad_c
• CO2 flux(fc)
• n_bad_irga_light
• covariance tc(cvar_tc)
• covaraince vc(cvar_vc)
• covariance qc(cvar_qc)
• skew_c
• rotated covariance uc(cvar_rot_uc)
• n_bad_q
• n_spk_q
• mean_spk_q

SGP/ECOR/E14 - Flux Measurements Incorrect

The ECOR datastream was corrupted; this happens when the ECOR program produces a 
datastream of the wrong length (i.e., leaves one or more measurements out).

Fluxes and some other measurements are incorrect.

Reprocessing will not correct this problem; the raw data are corrupted.

• Mean H2O density(mean_q)
• Corrected sensible heat flux(h)
• atm_pres
• Mean CO2 density(mean_c)
• temp_irga
• CO2 flux(fc)
• Latent heat flux(lv_e)

SGP/MWR/C1 - Spikes in ambient temperature readings

There are intermittent spikes in the Tkair temperature (T ~ 400 K). On 7/28 the sensor 
was cleaned and the instrument power cycled following a power outage. Readings came back to 
normal.

• tkair

• tkair

SGP/ECOR/E14 - Fluxes and Most Measurements Incorrect

The ECOR system was having major problems during this period and most measurements were 
incorrect most of the time.

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

SGP/MWR/C1/E14 - Freezing rain-Incorrect rain flag

Between 01/12 and 01/15 brightness temperatures show high values (Tb > 100 K) indicative 
of rain, however the wet_window flag is 0 (indicative of no rain). During that time there 
where freezing conditions with ice pellets that were not detected by the sensor. The high 
brightness temperatures may be due to melting ice on the window.

• wet_window

• wet_window

• wet_window

• wet_window

SGP/ECOR/E14 - IRGA Temperature Incorrect or Missing

The temp_irga was too large 05/09/07 1300 GMT - 05/10/07 2000 GMT.

The temp_irga was flat lined at 49.96 C 05/10/07 2030 GMT - 05/17/07 2000 GMT.  

The temp_irga was missing 05/17/07 2030 GMT - 05/19/07 1700 GMT.

• temp_irga

SGP/MWR/C1 - Noisy data

Since 7/14 the MWR is experiencing intermittent periods of increased noise. The cause for 
this is under investigation.

• liqtip
• vaptip
• tbsky23tip
• tbsky31tip
• tipsky23
• bbn23
• tipsky31
• bbn31
• bb23
• bb31

• bbn23
• bb23
• sky23
• 31.4 GHz sky brightness temperature(tbsky31)
• 23.8 GHz sky brightness temperature(tbsky23)
• Total liquid water along LOS path(liq)
• sky31
• bb31
• Total water vapor along LOS path(vap)
• bbn31

SGP/MWR/C1 - Reprocess: Radiometer reinstalled- Please reprocess

After the radiometer was reinstalled it had to update the calibration coefficients.
Data will be reprocessed

• Total water vapor along LOS path(vap)
• 31tbsky
• 23.8 GHz sky brightness temperature(tbsky23)
• Total liquid water along LOS path(liq)
• 23tbsky
• 31.4 GHz sky brightness temperature(tbsky31)

• tc23
• liqtip
• tbsky23tip
• tipsky23
• tipsky31
• tnd_nom23
• tnd31
• tc31
• vaptip
• tbsky31tip
• tnd_nom31
• tnd23

• tnd_nom31
• tc31
• 23.8 GHz sky brightness temperature(tbsky23)
• Total liquid water along LOS path(liq)
• tc23
• Total water vapor along LOS path(vap)
• tnd_nom23
• 31.4 GHz sky brightness temperature(tbsky31)
• tnd23
• tnd31

SGP/MWR/C1 - Missing data

Data are missing and unrecoverable.

• bbn23
• tkxc
• wet_window
• lon
• tnd_nom31
• tc31
• 23.8 GHz sky brightness temperature(tbsky23)
• Total liquid water along LOS path(liq)
• tkbb
• lat
• sky31
• tc23
• time_offset
• bb31
• Total water vapor along LOS path(vap)
• bbn31
• tkair
• bb23
• tnd_nom23
• sky23
• 31.4 GHz sky brightness temperature(tbsky31)
• tnd23
• Temperature, Sky Infra-Red(sky_ir_temp)
• base_time
• tnd31
• tknd
• alt

SGP/ECOR/E14 - Sensor failure

The water vapor output of the LI-7500 was too low, indicating that water vapor leaked into 
the sensor and that the chemicals are spent or there was an electronic failure.

Latent heat flux was not normally affected by this problem.

• Mean H2O density(mean_q)

SGP/MWR/C1 - Increased noise in 31.4 GHz channel

The 31.4 GHz channel has been showing an increased level of noise which results in 
increased noise in the LWP retrievals. The instrument is tipping and all other parameters seem 
to be in the range. The elevate noise started in May, but it seems to have become slightly 
worse after summer. After November the noise level seems to have gone back to normal.

• liqtip
• tbsky31tip

• 31.4 GHz sky brightness temperature(tbsky31)
• Total liquid water along LOS path(liq)

SGP/SEBS/E14 - Instrument logger problem

SEBS soil moisture measurements had been recorded as minimum soil moisture since the start 
of the SEBS installation at E14.  Soil heat capacity calculations were also incorrect as 
a result of the problem.

Instrument was mis-identified as ECOR in the DQPR.

Since the SEBS datastream was not available to list, I have had to select an ECOR 
datastream just to be able to submit this DQR.

Please add the SEBS to my listing of instrument systems for the purpose of submitting 
DQRs.

• base_time

SGP/ECOR/E14 - Instrument logger problem

Soil moisture measurements have been recorded as minimum soil moisture since the start of 
the SEBS installation at E14.

Please check the wiring of the soil moisture sensors to the multiplexer as follows:

1) Check that the yellow/green leads run from MUX 2, Common, Even, H/L to CR1000 4H/Gr.

2) Check that the 50K resistor is connected between CR1000 4H and excitation VX3.

Please report the results of these checks here.

Thanks.

• AVHRR satellite images for Darwin from BOM (RAW)(raw)

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

SGP/SEBS/E14 - Soil Moisture Measurements Incorrect

Soil Moisture measurements were incorrect because of a loose lead.

• measurements contained in this datastream are unknown