DQR ID | Subject | Data Streams Affected | Data Quality Metric |
---|
D010201.1 | NSA/MWR/C1 - Temperature Stabilization of Noise Diode Impaired | nsa5mwravgC1.c1 | Suspect |
D010202.8 | NSA/MWR/C2 - Wet-window flag incorrectly set | nsamwrlosC2.b1 | Suspect |
D010308.1 | NSA/MWR/C2 - Elevated sky brightness temperatures | nsamwrlosC2.b1 | Suspect |
D010504.2 | NSA/MWR/C2 - Missing data | nsamwrlosC2.b1 | Missing |
D011005.5 | SGP/MWR/E14 - calibration check | sgpmwrlosE14.b1 | Incorrect |
D011005.6 | SGP/MWR/E14 - Upgrade of Arm Core PC Configuration | sgpmwrlosE14.b1 | Missing |
D020119.1 | SGP/MWR/E14 - Hard disk failure | sgpmwrlosE14.b1 | Missing |
D020805.2 | SGP/MWR/B6 - Instrument replaced, calibration incorrect | sgp5mwravgB6.c1 | Incorrect |
D020805.3 | SGP/MWR/B6 - Instrument replaced, calibration updating | sgp5mwravgB6.c1 | Suspect |
D020824.4 | NSA/MWR/C2 - Instrument Maintenance | nsamwrlosC2.b1 | Incorrect |
D030312.7 | NSA/MWR/C2 - Intermittent Negative Sky Brightness Temperatures | nsamwrlosC2.b1 | Suspect |
D030724.1 | NSA/MWR/C2 - Thermally unstable | nsamwrlosC2.b1 | Suspect |
D030822.6 | SGP/MWR/E14 - min/max/delta values incorrect | sgpmwrlosE14.b1 | Does not affect quality |
D030909.3 | SGP/MWR/E14 - thermal instability | sgpmwrlosE14.b1 | Suspect |
D040102.4 | NSA/MWR/C2 - Heater problem | nsamwrlosC2.b1 | Suspect |
D041117.1 | SGP/MWR/E14 - Reprocess: wrong retrievals | sgpmwrlosE14.b1 | Incorrect |
D050202.1 | NSA/MWR/C2 - no air temperature signal | nsamwrlosC2.b1 | Missing |
D050705.1 | SGP/MWR/E14 - computer problem | sgpmwrlosE14.b1 | Does not affect quality |
D050725.2 | SGP/MWR/B1 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB1.c1 | Does not affect quality |
D050725.3 | SGP/MWR/B4 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB4.c1 | Does not affect quality |
D050725.4 | SGP/MWR/B5 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB5.c1 | Does not affect quality |
D050725.5 | SGP/MWR/B6 - Reprocess: Revised Retrieval Coefficients | sgp5mwravgB6.c1 | Does not affect quality |
D050725.6 | SGP/MWR/E14 - Reprocess: Revised Retrieval Coefficients | sgpmwrlosE14.b1 | Does not affect quality |
D050725.7 | NSA/MWR/C1 - Reprocess: Revised Calibration Coefficients | nsa5mwravgC1.c1 | Does not affect quality |
D050725.8 | NSA/MWR/C2 - Reprocessed: Revised Retrieval Coefficients | nsamwrlosC2.b1 | Does not affect quality |
D050725.9 | TWP/MWR/C1 - Reprocessed: Revised Retrieval Coefficients | twp5mwravgC1.c1 | Does not affect quality |
D050822.2 | SGP/MWR/E14 - Reprocessed and Corrected:thermal instability | sgpmwrlosE14.b1 | Does not affect quality |
D050830.1 | NSA/MWR/C2 - Thermally unstable | nsamwrlosC2.b1 | Suspect |
D050928.4 | NSA/MWR/C2 - New software version (4.15) installed | nsamwrlosC2.b1 | Does not affect quality |
D051011.3 | SGP/MWR/E14 - New software version (4.15) installed | sgpmwrlosE14.b1 | Does not affect quality |
Subject: | NSA/MWR/C1 - Temperature Stabilization of Noise Diode Impaired |
DataStreams: | nsa5mwravgC1.c1
|
Description: | On 1/17 we had a big spike in the data and lost temperature stabilization. The instrument
had problems maintaining the Noise Diode (ND) temperature since. At ambient temperatures
under about -20 C the ND was not maintaining the set temperature of 30 C. This problem
was reported in P010122.1.
Fred Solheim recommended on 1/22 that we powercycle the instrument as it looked like the
instrument CPU had lost the temperature reference.
So we powercycled the instrument on 1/22 @ 20:30 and lost all comumnication to it; after a
second powercycling the instrument came back on line and the temperature stabilized
quickly (within a couple of minutes) to the set temperature (30 C)
Fred Solheim reported after the system was restored:
"I've never seen this behavior before. I don't think it was due to the RF deck physically
hanging temperature, because the recorded temp dropped about 30 C in one observation
cycle. If this happens again, send the MWR down along with data files for us to look at."
Data collected in the periode 1/17/2001 6:00 to 1/22/2001 21:45 are questionable since it
is uncertain whether the temperature really was unstable and what really caused the
problem. |
Measurements: | nsa5mwravgC1.c1: - tbsky31_sdev
- tbsky23_sdev
- Total water vapor along LOS path(vap)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- water_flag_fraction
- ir_temp_sdev
- num_obs_irt
- liq_sdev
- num_obs
- Temperature, brightness, longwave(ir_temp)
- 23.8 GHz sky brightness temperature(tbsky23)
- vap_sdev
- Mean 31.4 GHz sky brightness temperature(tbsky31)
|
Subject: | SGP/MWR/B6 - Instrument replaced, calibration incorrect |
DataStreams: | sgp5mwravgB6.c1
|
Description: | MWR serial number 18 was replaced with MWR serial number 04 at 1652 on 2 Aug 2002.
Between this time and 2214, when a sufficient number of new tip curves were acquired to update
the calibration, the old calibration (for serial number 18) was used. During this period
the data are incorrect. |
Measurements: | sgp5mwravgB6.c1: - water_flag_periods
- time_offset
- num_obs_irt
- 23tbsky
- Total water vapor along LOS path(vap)
- dlm_flag_fraction
- Mean 31.4 GHz sky brightness temperature(tbsky31)
- tbsky31_sdev
- 23.8 GHz sky brightness temperature(tbsky23)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- Temperature, brightness, longwave(ir_temp)
- liq_sdev
- base_time
- North latitude(lat)
- East longitude(lon)
- num_obs_ir
- dlm_flag_periods
- vap_sdev
- ir_temp_sdev
- 31tbsky
- tbsky23_sdev
- Altitude above mean sea level(alt)
- water_flag_fraction
- num_obs
|
Subject: | SGP/MWR/B6 - Instrument replaced, calibration updating |
DataStreams: | sgp5mwravgB6.c1
|
Description: | Following replacement of the MWR at B6, an automatically and continuously upated median
calibration value was used based on data acquired during this period. After this period,
sufficient tip curves were available to automatically and continuously determine and
account for the temperature dependence of the calibration. |
Measurements: | sgp5mwravgB6.c1: - water_flag_periods
- time_offset
- num_obs_irt
- 23tbsky
- Total water vapor along LOS path(vap)
- dlm_flag_fraction
- Mean 31.4 GHz sky brightness temperature(tbsky31)
- tbsky31_sdev
- 23.8 GHz sky brightness temperature(tbsky23)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- Temperature, brightness, longwave(ir_temp)
- liq_sdev
- base_time
- North latitude(lat)
- East longitude(lon)
- num_obs_ir
- dlm_flag_periods
- vap_sdev
- ir_temp_sdev
- 31tbsky
- tbsky23_sdev
- Altitude above mean sea level(alt)
- water_flag_fraction
- num_obs
|
Subject: | NSA/MWR/C2 - Intermittent Negative Sky Brightness Temperatures |
DataStreams: | nsamwrlosC2.b1
|
Description: | Several related and recurring problems with the MWRs have been reported
dating back to 1999. These problems were due to the occurrence of
blackbody signals (in counts) that were half of those expected. The
symptoms included noisy data, spikes in the data, negative brightness
temperatures, and apparent loss of serial communication between the
computer and the radiometer, which results in a self-termination of the
MWR program.
Because these all initially appeared to be hardware-related problems,
the instrument mentor and site operations personnel (1) repeatedly
cleaned and replaced the fiber optic comm. components, (2) swapped
radiometers, (3) sent radiometers back to Radiometrics for evaluation
(which did not revealed any instrument problems), and (4) reconfigured
the computer's operating system. Despite several attempts to isolate
and correct it, the problem persisted.
It became apparent that some component of the Windows98 configuration
conflicted with the DOS-based MWR program or affected the serial port
or the contents of the serial port buffer. This problem was finally
corrected by upgrading the MWR software with a new Windows-compatible
program. |
Measurements: | nsamwrlosC2.b1: - Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- Mean 31.4 GHz sky brightness temperature(tbsky31)
- 23.8 GHz sky brightness temperature(tbsky23)
- Total water vapor along LOS path(vap)
|
Subject: | SGP/MWR/B1 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB1.c1
|
Description: | 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 SGP.B1 20020412.1600. The
MONORTM-based retrieval coefficients became active at SGP.B1 20050624.2100.
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. |
Measurements: | sgp5mwravgB1.c1: - Total water vapor along LOS path(vap)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
|
Subject: | SGP/MWR/B4 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB4.c1
|
Description: | 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 SGP.B4 20020415.2300. The
MONORTM-based retrieval coefficients became active at SGP.B4 20050624.2100.
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. |
Measurements: | sgp5mwravgB4.c1: - Total water vapor along LOS path(vap)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
|
Subject: | SGP/MWR/B5 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB5.c1
|
Description: | 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 SGP.B5
20020415.2300. The MONORTM-based retrieval coefficients became active
at SGP.B5 20050624.2100.
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. |
Measurements: | sgp5mwravgB5.c1: - Total water vapor along LOS path(vap)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
|
Subject: | SGP/MWR/B6 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgp5mwravgB6.c1
|
Description: | 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 SGP.B6
20020416.2200. The MONORTM-based retrieval coefficients became active
at SGP.B6 20050624.1942.
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. |
Measurements: | sgp5mwravgB6.c1: - Total water vapor along LOS path(vap)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
|
Subject: | SGP/MWR/E14 - Reprocess: Revised Retrieval Coefficients |
DataStreams: | sgpmwrlosE14.b1
|
Description: | 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 SGP.E14
20020416.0000. The MONORTM-based retrieval coefficients became active
at SGP.E14 20050628.2300.
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. |
Measurements: | sgpmwrlosE14.b1: - Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- Total water vapor along LOS path(vap)
|
Subject: | NSA/MWR/C1 - Reprocess: Revised Calibration Coefficients |
DataStreams: | nsa5mwravgC1.c1
|
Description: | 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. |
Measurements: | nsa5mwravgC1.c1: - Total water vapor along LOS path(vap)
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
|
Subject: | NSA/MWR/C2 - Reprocessed: Revised Retrieval Coefficients |
DataStreams: | nsamwrlosC2.b1
|
Description: | 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 water 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).
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: The NSA.C2 MWRLOS data for 19991018-20050630 have been reprocessed
to apply the MONORTM-based retrievals for all time. The reprocessed data
were archived in March 2007. The TIP data have not been reprocessed. |
Measurements: | nsamwrlosC2.b1: - Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- Total water vapor along LOS path(vap)
|
Subject: | TWP/MWR/C1 - Reprocessed: Revised Retrieval Coefficients |
DataStreams: | twp5mwravgC1.c1
|
Description: | 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).
The Rosenkranz-based retrieval coefficients became active at TWP.C1
20020504.0200. The MONORTM-based retrieval coefficients became active
at TWP.C1 20050630.2100.
Note: The TWP.C1 data for 19961011-20050630 have been reprocessed to apply the |
Measurements: | twp5mwravgC1.c1: - Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- Total water vapor along LOS path(vap)
|
Subject: | NSA/MWR/C2 - New software version (4.15) installed |
DataStreams: | nsamwrlosC2.b1
|
Description: | 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. |
Measurements: | nsamwrlosC2.b1: - sky23
- Temperature, brightness, longwave(ir_temp)
- tkxc
- tc31
- 23.8 GHz sky brightness temperature(tbsky23)
- Total water vapor along LOS path(vap)
- tkbb
- Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- bbn31
- tknd
- Mean 31.4 GHz sky brightness temperature(tbsky31)
- bbn23
- tc23
- tnd_nom23
- bb23
- Sky/Cloud Infrared Temperature(sky_ir_temp)
- sky31
- bb31
- tnd31
- tnd23
- tnd_nom31
- tkair
|
Subject: | SGP/MWR/E14 - New software version (4.15) installed |
DataStreams: | sgpmwrlosE14.b1
|
Description: | A problem began with the installation of MWR.EXE version 4.12 in May 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 8/1/2005. As a consequence of this
upgrade, the tip curve frequency increased. The tip cycle time decreased from ~60s to ~50s. |
Measurements: | sgpmwrlosE14.b1: - Water, liquid, total along line-of-sight path, mean, 5-min avg(liq)
- bbn31
- tknd
- 23.8 GHz sky brightness temperature(tbsky23)
- bbn23
- tnd31
- bb23
- Mean 31.4 GHz sky brightness temperature(tbsky31)
- tnd_nom31
- bb31
- tkbb
- tnd23
- tnd_nom23
- Total water vapor along LOS path(vap)
- sky23
- sky31
- tkair
- tc23
- tc31
- Sky/Cloud Infrared Temperature(sky_ir_temp)
- tkxc
|