Balloon-Borne Sounding System (BBSS)
Information updated on Sat May 22 21:19:25 2004
General Overview
Primary Quantities Measured with System
Primary Quantities Measured
The following quantities are measured as functions of time during a free-balloon ascent:- Pressure (hPa)
- Temperature (degC)
- Relative Humidity (%RH)
- Wind speed (m/s)
- Wind direction (deg)
- Altitude (gpm)
- Dew Point (degC)
- Ascent Rate (m/s)
- Latitude of Sonde (degN)
- Longitude of Sonde (degW)
- u-component of wind velocity (m/s)
- v-component of wind velocity (m/s)
Overall Uncertainties for Primary Quantities Measured
Several situations may arise during a sounding that may affect the quality of the data but which may not be flagged or otherwise corrected and the user should be aware of these. Among these are incorrect surface conditions, humidity sensor saturation or icing, and interference and signal confusion from other radiosondes. General data quality reports (DQRs) have been issued describing these conditions and the user is urged to read and understand these. Specific DQRs are issued for those cases when incorrect surface conditions are included in the soundings. Cases of sensor saturation (which may lead to unrealistic lapse rates or humidity values aloft, and of sonde-to-sonde interference which may result in incorrect data values are not generally called out in individual DQRs.
A general problem with Vaisala radiosondes is that they seem to exhibit a dry bias; that is, the RH values reported are too low. The amount of the error varies with several factors including the ambient temperature and RH and the age of the radiosonde but may be as great as 10% RH. The dry bias results from contamination of the humidity sensor during storage. Starting in August of of 1998 (week 33), Vaisala changed their packaging to reduce the problem. Another packaging change was made in August of 2000 that should effectively eliminate it from the RS-80 series of sondes. More detailed information may be found below in the FAQ, "What is this about dry bias in Vaisala radiosondes?"
Another issue involves soundings that are done in so-called RESEARCH mode for PTU (pressure, temperature, and humidity). These soundings, which may identified by data platform name wXpr, were done regularly at the SGP from 4/27/94 to 5/21/94; other cases isolated cases may exist in the archived data. Soundings done using RESEARCH mode (for PTU) Vaisala processing have a negative bias in the calculation of sonde altitude. This bias results from neglecting the sensed relative humidity when calculating air density when integrating the hydrostatic equation. In essence, the Vaisala RESEARCH mode (PTU) processing assumes a dry atmosphere when calculating sonde altitude. The magnitude of the bias is cumulative with height and will depend on the vertical distribution of moisture, but it can be as much as 20 meters at the tropopause (the RESEARCH-mode sounding altitudes will be smaller than altitudes calculated by using sensed RH). This problem applies to all soundings done in 'WXPR' mode, where X is either R or N. In particular, all soundings done during the April 1994 (RCS) IOP (4/7/94 to 5/21/94) are affected as well as those occasional inadvertent WXPR soundings. Note that the only variable affected is 'alt.'
Users interested corrected data for this time period should obtain files named as listed below. They can be retrieved via the Query Interface at the Archive or by special request to Archive User Services (armarchive@ornl.gov).
DsgpsondeptucalcB1.c1
DsgpsondeptucalcB4.c1
DsgpsondeptucalcB5.c1
DsgpsondeptucalcC1.c1
Detailed Description
List of Components
The BBSSs consist of disposable radiosondes and fixed ground stations. All facilities use the same basic radiosondes, but the ground stations differ somewhat. The SGP and TWP use Vaisala ground stations; the NSA uses a CLASS-type (Cross-Chain Loran Atmospheric Sounding System) that originally belonged to NOAA/CMDL. The NSA CLASS system will be replaced with a new Vaisala ground station in summer 2002.Radiosondes:
- Manufacturer: Vaisala, Inc.
- SGP: RS80-15LH (Loran-C windfinding, H-Humicap, 403 MHz) through April, 2001
- RS90-AL (Loran-C windfinding, dual humicap) beginning May, 2001
- TWP: RS80-15GH (GPS windfinding, H-Humicap, 403 MHz) through May, 2002 RS90-AG (GPS windfinding, dual humicap) beginning June, 2002
- NSA: RS80-15H (PTU only, H-Humicap, 403 MHz) used with CLASS through April, 2002
- RS90-A (PTU only, dual humicap) beginning April 25, 2002
- RS90-AG Occasionally in use beginning April 25, 2002
Ground Stations:
SGP
Central Facility:
We have two ground stations at the SGP Central Facility, digiCORA-II and a digiCORA-III. The digiCORA-II is the production system (data platform name sgpsondewXpXC1) and the digiCORA-III is being tested as a replacement (scheduled for late summer 2002). During the summer of 2002 two additional digiCORA-I systems will be used at the SGP for the AIRS validation IOP. See AIRS IOP. These systems will be designated "supplemental" with data platform names sgpsondewXpXS01 and sgpsondewXpXS02. The pcCORA system formerly at the SGP was sent to the NSA site for use during the AIRS validation IOP. See AIRS IOP
| Manufacturer: | Vaisala, Inc. | |
| Station Type: | MW-15 | digiCORA-II |
| Components: | UPP-20 | Receiver Processor |
| URR-20 | UHF Receiver | |
| MWV-201 | Navaid Processor | |
| MWG-201 | GPS Processor | |
| RM-21 | UHF Antenna | |
| GA-20 | GPS Antenna | |
| MF-12 | Floppy Disk (DD) Drive |
| Manufacturer: | Vaisala, Inc. | |
| Station Type: | PC-CORA | |
| Components: | PC | 486 Windows 3.1 |
| UR-15 | UHF Receiver | |
| SPL-11 | Loran Receiver | |
| SPU-11 | Loran Processor | |
| CG-21 | Antenna Set including
|
|
| GC-22 | Ground Check Set |
Boundary Facilities (All, except as noted):
| Manufacturer: | Vaisala, Inc. | |
| Station Type: | MW-11 | digiCORA |
| Components: | MF-12 | Floppy Disk (DD) Drive |
| UPP-15A | Receiver Processor | |
| UPP-20 | Receiver Processor (B6) | |
| UIF-15A | IF Unit (B1, B4, B5) | |
| URO-15 | Oscillator (B1, B4, B5) | |
| URR-20 | UHF Receiver | |
| RB-21 | Directional UHF Antenna |
TWP
The ground stations at ARCS1 (Manus Island, PNG) and
ARCS2 (Republic of Nauru) are identical digiCORA-IIs.
| Manufacturer: | Vaisala, Inc. | |
| Station Type: | MW-15 | digiCORA-II |
| Components: | UPP-20 | Receiver Processor |
| URR-20 | UHF Receiver | |
| MWV-201 | Navaid Processor | |
| MWG-201 | GPS Processor | |
| RM-21 | UHF Antenna | |
| GA-20 | GPS Antenna | |
| PCMF | Raw Data Collection Software |
NSA
The ground station at Barrow, AK is an old CLASS-type (Cross Chain Loran Atmospheric Sounding System).
| Manufacturer: | ||
| Station Type: | CLASS |
Description of System Configuration and Measurement Methods
Original sampling rate (5/27/92 to 5/30/93):The raw sampling rate of thermodynamic sensors is approximately 1.5 seconds. The rate at which processed data is output to the data stream is programmable. For the first several months of operation at the Southern Great Plains/Cloud and Radiation Testbed (SGP/CART) site, we used a scheme in which PTU and wind data were output at three different rates, depending on the time into the sounding. These sampling rates were:
- Sample output every 10 seconds from 0 to 120 seconds into the flight.
- Sample output every 30 seconds from 120 to 900 seconds into the flight.
- Sample output every 60 seconds from 900 seconds to the end of the flight.
- Thermodynamic variables (PTU) output every 10 seconds throughout the flight.
- Wind variables (speed, direction) were not measured.
- Thermodynamic variables (PTU) output every 2 seconds throughout the flight.
- Wind variables (speed, direction):
- Output every 10 seconds (SGP)
- Output every 2 seconds (TWP)
- Thermodynamic variables (PTU) output every 2 seconds throughout the flight.
- Wind variables (speed, direction) output every 2 seconds throughout the flight.
ARM uses 350 g balloons at all sites. The nominal ascent rate is approximately 5 m/s, although this is variable during the flight. The data file includes a variable 'asc' which, for each sample, estimates the current rate of ascent. This rate is actually a 30-second average rise rate based on the calculated sonde altitudes.
Software Configuration of the SGP digiCORA Systems
- The following is the current software configuration listing for the Vaisala MW-11 digiCORA systems now in use at the Southern Great Plains Cloud and Radiation Testbed site. These systems are installed at BF1 (Hillsboro, KS), BF4 (Vici, OK), BF5 (Morris, OK), and BF6 (Purcell, OK). The configuration listings show the installed software applications as well as their version numbers.
Configuration 10 JUN 99 14:23 UTC Installed software: Programs of processors MPUS 8.28 7226 MWSS 7.32 5184 MPPS 4.02 7041 MWLS 4.03 5230 MWGS20 2.02 8272 SE1E99 UPP710 7.10 0290 Loadable programs CONFIG 08.21 8030 MW11.8222 SYSPUP 08.29 7315 SYSP829A SYSGEN 08.28 7310 SYSG828B HIMEM 08.21 5062 HIMEM_MOD DISPSERV08.27 7295 DISP827 SWSSERV 08.21 7300 SWSS821 PTUSERV 08.29 7295 PTUS829B PCSERV 08.24 7162 PCSE824 LORSERV 08.28 7330 LORS828_MWL GPSSERV 08.29 7330 GPSS829 MFSERV 08.21 4341 MFSE821 SOND 08.29 7349 SOND829D LORWCMP 08.23 5285 LORW823 GPSWCMP 08.28 7286 GPSW828A NAVDER 08.27 7314 NAVD827 SIMUL 08.21 5066 SIMUL_MOD SIGPAR 08.21 5066 SIGPAR_MOD COMPAR 08.21 5066 COMPAR_MOD FORMOUT 08.21 5066 FORMOUT_MOD ADDOUT 08.21 5066 ADDOUT_MOD RESEARCH08.21 5066 RESEARCH_MOD TEMP 08.24 7244 TEPI824_RT PILOT 08.24 7244 TEPI824_RT LIST 08.22 5289 LIST822 STATUS 08.22 5268 STAT822 MFLOAD 08.22 7086 MFLO822 MFSAVE 08.21 5066 MFSA821 METPAR 08.21 5178 METP821
- The following is the configuration listing for the Vaisala digiCORAII now in use at the Southern Great Plains Cloud and Radiation Testbed site. This system is installed at the Central Facility.
Configuration 9 JUN 99 22:08 UTC Installed software: Programs of processors MPUS 8.28 7226 PPCS 1.11 6082 UPPS20 3.03 7192 MWVS20 04.21 7330 MWGS20 2.02 8272 SE1E99 Loadable programs CONFIG 08.21 8030 MW15.8222 SYSPUP 08.29 7315 SYSP829A SYSGEN 08.28 7310 SYSG828B HIMEM 08.21 5062 HIMEM_MOD DISPSERV08.27 7295 DISP827 SWSSERV 08.21 7300 SWSS821 PTUSERV 08.29 7295 PTUS829B PCSERV 08.24 7162 PCSE824 OMESERV 08.27 7330 OMES827 VLFSERV 08.27 7330 VLFS827 LORSERV 08.28 7330 LORS828 GPSSERV 08.29 7330 GPSS829 MFSERV 08.21 4341 MFSE821 SOND 08.29 7349 SOND829D OMEWCMP 08.25 7309 OMEW825 LORWCMP 08.23 5285 LORW823 GPSWCMP 08.28 7286 GPSW828A NAVDER 08.27 7314 NAVD827 SIMUL 08.21 5066 SIMUL_MOD SIGPAR 08.21 5066 SIGPAR_MOD COMPAR 08.21 5066 COMPAR_MOD FORMOUT 08.21 5066 FORMOUT_MOD ADDOUT 08.21 5066 ADDOUT_MOD RESEARCH08.21 5066 RESEARCH_MOD TEMP 08.24 7244 TEPI824_RT PILOT 08.24 7244 TEPI824_RT LIST 08.22 5289 LIST822 STATUS 08.22 5268 STAT822 MFLOAD 08.22 7086 MFLO822 MFSAVE 08.21 5066 MFSA821 METPAR 08.21 5178 METP821
Current SYSGEN Listing
- The following is a listing of the current SYSGEN (system program) for the MW11/MW15 digiCORA systems used at the SGP/CART site. This listing shows all the system parameter settings now in use.
SYSPAR Rev. 07.09 99-06-10 14:07:14
Initialized: 97-11-11 12:10:00
Latest modification: 99-01-20 21:38:38
Device Type MW11
Line description MWL MF MWG SWS PTP PRT
Line status On/Test On On/Test Off Off On
Cable Number I 4 P8(422) I 6 P 5 P 4 P 2
Line speed (bps) 19200 19200 9600 1200 300 9600
Parity None None None None None None
Number of data bits 8 8 8 8 8 8
Number of stop bit 1 1 1 1 1 1
Line timeout 10 10 10 30 10 10
Terminal / FM source HCopy HCopy FMcable HCopy HCopy EpsonFX
XON/XOFF type Off Off Off Off Normal Off
Line description PRT2 CRT1 PC EXT1 EXT_PTU
Line status Off Off On Off Off
Cable Number P 3 P 3 P 1 P 4 P 5
Line speed (bps) 1200 9600 9600 9600 2400
Parity None None None None None
Number of data bits 8 8 8 8 8
Number of stop bits 1 1 1 1 1
Line timeout 10 10 10 10 10
Terminal / FM source EpsonFX WY-50 HCopy HCopy HCopy
XON/XOFF type Normal Normal Off Normal Off
SYSPAR Rev. 07.09 99-06-10 14:07:19
Initialized: 97-11-11 12:10:00
Latest modification: 99-01-20 21:38:38
Station data parameters
Latitude (deg) 38.30 deg
Longitude (deg) -97.30 deg
Altitude 447 m
WMO Region Code 4
WMO Block Code 74
WMO Station number 547
Station name SGP/CART/HILLSBORO1
Station report type FIXED
Coordinate input Disabled
Simulation option On
Research mode option On
Store data option On
Ground check type Disabled
Sounding start type Auto
Maximum duration 120 min
Maximum height 40 km
Minimum pressure 3 hPa
Ground obs type Operator
Unit for Ground T degC
Unit for Ground Dir deg
Unit for Ground Spe m/s
TEMP Section 7 On
Cloud group input Off
Special group1 input Off
Special group2 input Off
Sounding number flag On
Message time input None
SYSPAR Rev. 07.09 99-06-10 14:07:24
Initialized: 97-11-11 12:10:00
Latest modification: 99-01-20 21:38:38
Output control parameters
Output layer rec 1:
Type of use Ascent
Output device PRT P 2
Output data type 0
Layer start 1: 0 s
Record interval 1: 2 s
Layer start 2: 14400 s
Record interval 2: 0 s
Output header flag Off
Output record in use
Time AscRate Hgt/MSL Pressure Temp RH Dewp Dir Speed WndStat
min s m/s m hPa degC % degC deg m/s
xxx xx xxxxx.x xxxxxxx xxxxxx.x xxxx.x xxx xxxx.x xxxx xxx.x xxxxxxxxxxx
Output record 1:
Time AscRate Hgt/MSL Pressure Temp RH Dewp Dir Speed WndStat
min s m/s m hPa degC % degC deg m/s
xxx xx xxxxx.x xxxxxxx xxxxxx.x xxxx.x xxx xxxx.x xxxx xxx.x xxxxxxxxxxx
Message processing parameters
Message program TEMP A
Processing status On
Message triggering AftTerm
Message distribution Auto
Msg output line PRT P 2
Header None
Footer 1
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program TEMP B
Processing status On
Message triggering AftTerm
Message distribution Auto
Msg output line PRT P 2
Header None
Footer 1
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program STATUS
Processing status On
Message triggering AftTerm
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Message program TEMP D
Processing status Off
Message triggering Operator
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program PILOT A
Processing status Off
Message triggering Operator
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program PILOT B
Processing status Off
Message triggering Operator
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program PILOT C
Processing status Off
Message triggering Operator
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program PILOT D
Processing status Off
Message triggering Operator
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Message program TEMP C
Processing status Off
Message triggering Operator
Message distribution Auto
Msg output line PRT P 2
Header 1
Footer None
Conversion /PRT ASCII
Msg output line PTP Off
Header None
Footer 2
Conversion /PTP TELEX
Reverse bit order No
Trigger record 1: Off
Trigger record 2: Off
Trigger record 3: Off
Trigger record 4: Off
Trigger record 5: Off
Trigger record 6: Off
Trigger record 7: Off
Trigger record 8: Off
Trigger record 9: Off
Trigger record 10: Off
General message parameters
TEMP wind speed unit kts
Hdr Time round up 30 min
Hdr Time round down 30 min
Msg Time round up 30 min
Msg Time round down 30 min
Downwards extr level 1000 hPa
First PILOT STD Lev 850 hPa
PTU only TEMP No
Shear group in maxw Yes
New sect-> new line No
Double space Yes
More than two trops No
Incl.incomplete trop No
Nbr of groups/line 10
Min T to report DPD -60 degC
Message standard levels
STD Pressure/Hgt 1: 1000 --
STD Pressure/Hgt 2: 925 --
STD Pressure/Hgt 3: 850 1500
STD Pressure/Hgt 4: 700 3000
STD Pressure/Hgt 5: 500 5400
STD Pressure/Hgt 6: 400 7200
STD Pressure/Hgt 7: 300 9000
STD Pressure/Hgt 8: 250 10500
STD Pressure/Hgt 9: 200 12000
STD Pressure/Hgt 10: 150 13500
STD Pressure/Hgt 11: 100 15900
STD Pressure/Hgt 12: 70 18300
STD Pressure/Hgt 13: 50 20700
STD Pressure/Hgt 14: 30 23700
STD Pressure/Hgt 15: 20 26400
STD Pressure/Hgt 16: 10 30900
Message fixed regional levels
Mess vert level par Pressure hPa
Message level 1: 900 hPa
Message level 2: 800 hPa
Message level 3: 600 hPa
Header text records:
Header record nbr 1:
<CR><LF> <CR><LF> ~SWY2~SWM2~SWD2<SP>~SWH2:~SWm2<CR><LF> <CR><LF>
Header record nbr 2;
<CR><LF> <LF> <LF> <LF> <LF> <LF> <LF> <LF> NNNN<CR><LF>
SYSPAR Rev. 07.09 99-06-10 14:07:35
Initialized: 97-11-11 12:10:00
Latest modification: 99-01-20 21:38:38
General PTU params :
Sonde type 0
Median window length 11
Computing density 2 s
GC limit/P 6.0 hPa
GC limit/T 2.0 degC
GC limit/RH 7.0 %
Autostart parameter:
Thresh of P change 5.0 hPa
Limit of P change 12.5 hPa
Nbr of peaks of P 0
Number of P samples 24
Max dt of starttimes 5 s
Number of starttimes 5
Autostop parameters:
P trigger for test 1080.0 hPa
Thresh of P change 5.0 hPa
Limit of P change 12.5 hPa
Number of P peaks 0
Number of P samples 24
Max time with no P 720 s
PTU editing params :
Max interp time /P 4 min
Max interp time /T 4 min
Max interp time /RH 2 min
Smoothing tol /T 0.5 degC
rawtgrad 1.2 K/100m
rawtcl -2.0 degC
rawttmx 30.0 degC
fricdmin -1.6 K/100m
fricdmax 1.4 K/100m
freedmin -1.4 K/100m
freedmax 1.2 K/100m
Smoothing tol /RH 5 %
Nbr of smooth /P 3
Nbr of smooth /T 3
Nbr of smooth /RH 3
T/U Siglev params :
Trop/ sigp effect On
Press/sigp effect On
Force 100hPa SigLev On
Force 1st EDT SigLev Off
Force T sigp -> RH Off
Lowest level/tropop 500.0 hPa
Threshold for isot 0.0 degC
Thickness for isot 20.0 hPa
RH change in isot 20 %
1st tolerance sigp/T 1.0 degC
P to change 1st->2nd 300.0 hPa
2nd tolerance sigp/T 2.0 degC
Tolerance sigp/RH 15 %
plimisoinv 300.0 hPa
RH tol / join to T 6 %
Wind Process params:
Max interp time 1 min
Edit buffer length 6
Editing level 100 %
Smooth buffer length 11
Smoothing level 30
Wind Siglev params :
1st tol for sigp/dd 10 deg
1st tol for sigp/ff 5.0 m/s
P to change 1st->2nd 3.0 hPa
2nd tol for sigp/dd 10 deg
2nd tol for sigp/ff 5.0 m/s
Speed limit for MAXW 30.0 m/s
Lowest level/MAXW 500.0 hPa
spddffthres 5.0 m/s
Force 100hPa siglev On
Force 1st EDT SigLev Off
Calm strata boundary Off
NIL strata boundary On
Level in NIL strata On
Wait incomplete maxw On
Use CAN_MAXFF Off
Dir tol / join to FF 6 deg
SYSPAR Rev. 07.09 99-06-10 14:07:39
Initialized: 97-11-11 12:10:00
Latest modification: 99-01-20 21:38:38
LoranC wind params :
Number of chains 2
Chain ID 1: 8970
Station OFF/ON 1: On
Station OFF/ON 2: On
Station OFF/ON 3: On
Station OFF/ON 4: On
Station OFF/ON 5: On
Chain ID 2: 9610
Station OFF/ON 1: On
Station OFF/ON 2: On
Station OFF/ON 3: On
Station OFF/ON 4: On
Station OFF/ON 5: On
Station OFF/ON 6: On
Buffer control param Time
Start of layer 1: 0 s
Buffer length 1: 60 s
Start of layer 2: 14400 s
Buffer length 2: 0 s
Computation mode Remote
Chain Id GRI Slave Delay Latitude Longitude
1 4970 49.70 ms 65.97 deg 60.31 deg
1 11.000 ms 76.13 deg 60.22 deg
2 25.000 ms 69.12 deg 35.67 deg
2 5930 59.30 ms 46.81 deg -67.93 deg
1 11.000 ms 41.25 deg -69.98 deg
2 25.000 ms 46.78 deg -53.17 deg
3 38.000 ms 52.38 deg -55.71 deg
3 5970 59.70 ms 36.18 deg 129.34 deg
1 11.000 ms 42.74 deg 143.72 deg
2 31.000 ms 35.04 deg 126.54 deg
3 42.000 ms 26.61 deg 128.15 deg
4 5990 59.90 ms 51.97 deg -122.37 deg
1 11.000 ms 55.44 deg -131.26 deg
2 27.000 ms 47.06 deg -119.74 deg
3 41.000 ms 50.61 deg -127.36 deg
5 6731 67.31 ms 49.15 deg -1.50 deg
1 10.992 ms 43.74 deg -1.38 deg
2 24.986 ms 52.58 deg -9.82 deg
3 39.028 ms 54.81 deg 8.29 deg
6 7001 70.01 ms 68.64 deg 14.46 deg
1 11.014 ms 70.91 deg -8.73 deg
2 27.034 ms 70.84 deg 29.22 deg
7 7030 70.30 ms 20.47 deg 44.58 deg
1 11.000 ms 24.83 deg 50.57 deg
2 26.000 ms 23.81 deg 42.85 deg
3 40.000 ms 28.15 deg 34.76 deg
4 56.000 ms 16.43 deg 42.80 deg
8 7270 72.70 ms 49.33 deg -54.86 deg
1 11.000 ms 46.78 deg -53.17 deg
2 25.000 ms 52.38 deg -55.71 deg
9 7430 74.30 ms 37.06 deg 122.32 deg
1 11.000 ms 31.07 deg 118.89 deg
2 28.000 ms 42.72 deg 129.11 deg
10 7499 74.99 ms 54.81 deg 8.29 deg
1 11.028 ms 49.15 deg -1.50 deg
2 26.986 ms 61.30 deg 4.70 deg
11 7950 79.50 ms 51.08 deg 142.70 deg
1 11.000 ms 53.13 deg 157.70 deg
2 30.000 ms 44.53 deg 131.64 deg
3 46.000 ms 42.74 deg 143.72 deg
4 61.000 ms 59.42 deg 143.09 deg
12 7960 79.60 ms 63.33 deg -142.81 deg
1 11.000 ms 57.44 deg -152.37 deg
2 26.000 ms 55.44 deg -131.26 deg
3 44.000 ms 65.24 deg -166.89 deg
13 7980 79.80 ms 30.99 deg -85.17 deg
1 11.000 ms 30.73 deg -90.83 deg
2 23.000 ms 26.53 deg -97.83 deg
3 43.000 ms 27.03 deg -80.11 deg
4 59.000 ms 34.06 deg -77.91 deg
14 7990 79.90 ms 38.87 deg 16.72 deg
1 11.000 ms 35.52 deg 12.53 deg
2 29.000 ms 40.97 deg 27.87 deg
3 47.000 ms 42.06 deg 3.20 deg
15 8000 80.00 ms 53.13 deg 34.91 deg
1 10.000 ms 61.76 deg 33.69 deg
2 25.000 ms 53.13 deg 25.40 deg
3 50.000 ms 44.89 deg 33.87 deg
4 65.000 ms 53.29 deg 48.11 deg
16 8290 82.90 ms 48.74 deg -109.98 deg
1 11.000 ms 48.61 deg -94.56 deg
2 27.000 ms 44.00 deg -105.62 deg
3 42.000 ms 51.97 deg -122.37 deg
17 8390 83.90 ms 31.07 deg 118.89 deg
1 11.000 ms 23.72 deg 116.90 deg
2 29.000 ms 37.06 deg 122.32 deg
18 8830 88.30 ms 23.81 deg 42.85 deg
1 11.000 ms 24.83 deg 50.57 deg
2 25.000 ms 20.47 deg 44.58 deg
3 40.000 ms 28.15 deg 34.76 deg
4 56.000 ms 16.43 deg 42.80 deg
19 8930 89.30 ms 34.40 deg 139.27 deg
1 11.000 ms 26.61 deg 128.15 deg
2 30.000 ms 24.29 deg 153.98 deg
3 50.000 ms 42.74 deg 143.72 deg
4 70.000 ms 36.18 deg 129.34 deg
20 8940 89.40 ms 49.15 deg -1.50 deg
1 12.000 ms 43.74 deg -1.38 deg
2 30.000 ms 54.81 deg 8.29 deg
21 8970 89.70 ms 39.85 deg -87.49 deg
1 11.000 ms 30.99 deg -85.17 deg
2 28.000 ms 42.71 deg -76.83 deg
3 44.000 ms 48.61 deg -94.56 deg
4 59.000 ms 36.51 deg -102.90 deg
22 9007 90.07 ms 62.30 deg -7.07 deg
1 10.984 ms 70.91 deg -8.73 deg
2 23.952 ms 68.64 deg 14.46 deg
3 38.998 ms 61.30 deg 4.70 deg
4 52.046 ms 52.58 deg -9.82 deg
23 9610 96.10 ms 36.51 deg -102.90 deg
1 11.000 ms 44.00 deg -105.62 deg
2 25.000 ms 35.32 deg -114.80 deg
3 40.000 ms 32.07 deg -106.87 deg
4 52.000 ms 26.53 deg -97.83 deg
5 65.000 ms 30.73 deg -90.83 deg
24 9930 99.30 ms 36.18 deg 129.34 deg
1 11.000 ms 35.04 deg 126.54 deg
2 22.000 ms 26.61 deg 128.15 deg
3 37.000 ms 34.40 deg 139.27 deg
4 51.000 ms 44.53 deg 131.64 deg
25 9940 99.40 ms 39.55 deg -118.83 deg
1 11.000 ms 47.06 deg -119.74 deg
2 27.000 ms 38.78 deg -122.50 deg
3 40.000 ms 35.32 deg -114.80 deg
26 9960 99.60 ms 42.71 deg -76.83 deg
1 11.000 ms 46.81 deg -67.93 deg
2 25.000 ms 41.25 deg -69.98 deg
3 39.000 ms 34.06 deg -77.91 deg
4 54.000 ms 39.85 deg -87.49 deg
27 9970 99.70 ms 24.80 deg 141.33 deg
1 11.000 ms 24.29 deg 153.98 deg
2 30.000 ms 42.74 deg 143.72 deg
3 55.000 ms 26.61 deg 128.15 deg
4 81.000 ms 13.46 deg 144.83 deg
28 9990 99.90 ms 57.15 deg -170.25 deg
1 11.000 ms 52.83 deg 173.18 deg
2 29.000 ms 65.24 deg -166.89 deg
3 43.000 ms 57.44 deg -152.37 deg
30 7970 79.70 ms 62.30 deg -7.07 deg
1 11.000 ms 68.64 deg 14.46 deg
2 26.000 ms 54.81 deg 8.29 deg
3 46.000 ms 64.91 deg -23.92 deg
4 60.000 ms 70.91 deg -8.73 deg
SYSPAR Rev. 07.09 99-06-10 14:07:52
Initialized: 97-11-11 12:10:00
Latest modification: 99-01-20 21:38:38
GPS parameters :
Station type FIXED
Range to launch site 0.00 km
Dir to launch site 0.00 deg
Alt to launch site 0 m
Station elev mask 3 deg
Calculation mode Diff
Sonde elevation mask 3 deg
Ionos./tropos. model No
Sounding type 1
Default vert. speed 5.0 m/s
Max sonde speed 120 m/s
Max sonde accel. 20 m/(s*s)
Detection threshold 43
IF lower bound 6500 Hz
IF upper bound 17500 Hz
Tight search 200 Hz
Coarse search 600 Hz
Filter type 5
Filter bank index 1
Maximum time delay 240 s
Minimum data density 0.40
Output rate 0.5 s
Timeout 600 s
FSK frequency type Vaisala
Navigation aiding None
UHF Receiver Params:
IF Bandwidth Wide
Track Off
Afc On
Scan Off
Elevation 45
Azimuth NE
Automatic antenna On
Default frequency 401.00 MHz
1st spare frequency 400.01 MHz
2nd spare frequency 405.99 MHz
Description of Observational Specifications
The manufacturer's specifications for the thermodynamic sensors are as follows:PRESSURE
Type: Capacitive aneroid
Range: 1060 hPa to 3 hPa
Resolution: 0.1 hPa
Accuracy: 0.5 hPa
TEMPERATURE
Type: Capacitive bead
Range: +60 degC to -90 degC
Resolution: 0.1 degC
Accuracy: 0.2 degC
Lag: <2.5 s (6 m/s flow at 1000 hPa)
HUMIDITY
Type: H-HUMICAP thin film capacitor
Range: 0 to 100 %RH
Resolution: 1 %RH
Accuracy: 2 %RH (0 to 80 %RH)
3 %RH (80 to 100 %RH)
Lag: 1 s (6 m/s flow at 1000 hPa, +20 degC)
Note that the "accuracy" figures given by the manufacturer represent the standard deviation of the differences obtained from repeated calibrations. As such, these values are more properly termed "precision." Operational experience at the SGP/CART site (Lesht, 1995) showed that the RMS error in RH was approximately 1% RH at low humidity and surface temperature and that the RMS error in temperature was approximately 0.3 deg C.
WINDS
Wind information (SGP) is obtained by tracking the radiosonde's position using the Loran-C navigation system. The accuracy of the wind information depends on the configuration of the Loran-C stations that are used to locate the sonde. Loran-C coverage in the SGP/CART area is fairly good, and we estimate the accuracy of the wind speed to be approximately 0.5 m/s.
We use GPS (global positioning system) wind-finding at the TWP locations. This satellite-
based navigation system is very precise and we estimate the accuracy of the wind velocity
to be 0.2 m/s.
Theory of Operations
This information is currently unavailable.Current Status and Locations
At the NSA site--- Barrow, (Great White) 71.32N, 156.62W, 27 m
- Install digiCORA-III (MW-21) 4/24/02
- Install pc-CORA 7/22/02 (for AIRS validation IOP)
- Manus Island, PNG (ARCS1) 2.06S, 147.43E, 4 m
- Assigned WMO station identifier (044 block 92)
- Install Synergetics DCP 07/2000
- Republic of Nauru (ARCS2) 0.52S, 166.92E, 7 m
- Assigned WMO station identifier (532 block 91)
- Install Synergetics DCP 07/2000
- Central Facility (CF) 36.61N, 97.49W, 315 m
- System installed 5/27/92
- Start regular (19:30) soundings 7/14/92
- Start ground checks 1/21/93
- Change to high resolution sampling (2-sec) 5/20/93
- Install RESEARCH software 3/30/94
- Start RESEARCH mode soundings 4/7/94
- Stop RESEARCH mode soundings 5/21/94
- Stop ground checks 8/3/94
- Install RAWDATA software 11/15/94
- Assigned WMO station identifier (646 block 74) 8/19/96
- Software upgrade to generate WMO-coded messages for NWS 3/24/97
- Install MW-15 digiCORA-II 9/1/97 for WVIOP
- Change regular sounding schedule from 5 per day to 3 per day 11/14/97
- Add 0530 UTC sounding to regular schedule (1130, 2030, 2330) 11/30/98
- Switch from PC-CORA to digiCORA-II for soundings 4/13/99
- Update PC-CORA and digiCORA-II and MF-12 for Y2K 6/9/99
- Stop RESEARCH mode for winds 11/24/00
- Begin operational use of RS-90 radiosondes 5/1/01
- Change sounding schedule to 0530, 1130, 1730, 2330 8/1/01
- Transfer PC-CORA to NSA 6/24/02
- Begin MW-21 transition IOP 7/10/02
- Hillsboro, KS (BF1) 38.30N, 97.30W, 447 m
- Installed 1/18/94
- Start RESEARCH mode soundings 4/7/94
- Stop RESEARCH mode soundings 5/21/94
- Installed directional antenna 3/28/96
- Assigned WMO station identifier (547 block 74) 8/19/96
- Start automatic generation of WMO-coded messages 10/28/96
- Added GPS windfinding capability 3/25/97
- Suspend daily soundings at all BFs 11/22/97
- Update digiCORA and MF-12 for Y2K 6/11/99
- Stop RESEARCH mode for winds 11/24/00
- Vici, OK (BF4) 36.07N, 99.20W, 622 m
- Installed 1/18/94
- Start RESEARCH mode soundings 4/7/94
- Stop RESEARCH mode soudnings 5/21/94
- Installed directional antenna 7/1/96
- Assigned WMO station identifier (641 block 74) 8/19/96
- Start automatic generation of WMO-coded messages 10/28/96
- Added GPS windfinding capability 3/26/97
- Suspend daily soundings at all BFs 11/22/97
- Update digiCORA and MF-12 for Y2K 6/11/99
- Stop RESEARCH mode for winds 11/24/00
- Morris, OK (BF5) 35.68N, 95.85W, 217 m
- Installed 1/18/94
- Start RESEARCH mode soundings 4/7/94
- Stop RESEARCH mode soudnings 5/21/94
- Assigned WMO station identifier (650 block 74) 8/19/96
- Start automatic generation of WMO-coded messages 10/28/96
- Added GPS windfinding capability 3/27/97
- Suspend daily soundings at all BFs 11/22/97
- Update digiCORA and MF-12 for Y2K 6/11/99
- Stop RESEARCH mode for winds 11/24/00
- Purcell, OK (BF6) 34.97N, 97.42W, 344 m
- Installed 10/13/94
- Removed borrowed directional antenna 2/17/95
- Installed new directional antenna 10/2/95
- Assigned WMO station identifier (651 block 74) 8/19/96
- Start automatic generation of WMO-coded messages 10/31/96
- Added GPS windfinding capability 3/25/97
- Suspend daily soundings at all BFs 11/22/97
- Update digiCORA and MF-12 for Y2K 6/11/99
- Stop RESEARCH mode for winds 11/24/00
Data Quality
Data Quality Health and Status
The following links go to current data quality health and status results.
The tables and graphs shown contain the techniques used by ARM's data quality analysts, instrument mentors, and site scientists to monitor and diagnose data quality.
Click on one of the links below to look at the current/recent data quality or operational health and status of BBSS. These various sources will provide you with an idea of how ARM data quality analysts, instrument mentors, site scientists, and site operators closely monitor instrument performance in the real time.
- SGP
Data Quality Health and Status (click on "Instrument", "BBSS", and "BBSS DQ")
Sounding Status Reports
Prelaunch Logs
Data Availability (click on desired time period and then locate "BBSS")
NSA
Barrow - Current Health and Status (look for "Sonde ASCII File Count")
Atqasuk - Current Health and Status (look for "Sonde ASCII File Count")- TWP
Manus - Current Health and Status (look for six "Sonde" diagnostics)
Nauru - Current Health and Status (look for six "Sonde" diagnostics)
Data User Notes
General
Several situations may arise during a sounding that may affect the quality of the data but which may not be flagged or otherwise corrected, and the user should be aware of these. Among these are incorrect surface conditions, humidity sensor saturation or icing, interference and signal confusion from other radiosondes. General data quality reports (DQRs) have been issued describing these conditions and the user is urged to read and understand these. Specific DQRs are issued for those cases when incorrect surface conditions are included in the soundings. Cases of sensor saturation (which may lead to unrealistic lapse rates or humidity values aloft, and of sonde-to-sonde interference which may result in incorrect data values are not generally called out in individual DQRs.
Dry Bias
A general problem with Vaisala radiosondes is that they seem to exhibit a dry bias; that is, the RH values reported are too low. The amount of the error varies with several factors including the ambient temperature and RH and the age of the radiosonde but may be as great as 10% RH. The dry bias results from contamination of the humidity sensor during storage. Starting in August of of 1998 (week 33), Vaisala changed their packaging to reduce the problem. Another packaging change was made in August of 2000 that should effectively eliminate it from the RS-80 series of sondes. More detailed information may be found in a FAQ below, called "What is this about 'dry bias' in Vaisala radiosondes?".
STATUS Message
Soundings done at the SGP (BFs and CF digiCORA) and at the TWP include a STATUS message in the netCDF metadata. This STATUS message contains information about the overall quality of the sounding. Among the information included in the status message is the percent of good telemetry, and the percent of samples that did not pass the internal quality checks. The format of the STATUS message is explained below in the FAQ section.
Automated Quality Control/flagging contained within netCDF files
Some automated data quality checks are included in the processed BBSS netCDF file. Checks now used are based on pre-defined limits for maximum, minimum, and sample-to-sample change (delta) values of each raw variable. The following limits are used for BBSS:Variable |
Name |
Units |
SGP |
TWP |
NSA |
||||||
Min |
Max |
Delta |
Min |
Max |
Delta |
Min |
Max |
Delta |
|||
pres |
pressure |
hPa |
0.0 |
1100.0 |
10.0 |
0.0 |
1100.0 |
10.0 |
0.0 |
1100.0 |
50.0 |
tdry |
dry bulb temperature |
C |
-80.0 |
50.0 |
10.0 |
-80.0 |
50.0 |
10.0 |
-80.0 |
50.0 |
50.0 |
dp |
dewpoint temperature |
C |
-110.0 |
50.0 |
---- |
-110.0 |
50.0 |
---- |
-110.0 |
50.0 |
50.0 |
wspd |
wind speed |
m/s |
0.0 |
75.0 |
---- |
0.0 |
75.0 |
---- |
---- |
---- |
---- |
deg |
wind direction |
deg |
0.0 |
360.0 |
---- |
0.0 |
360.0 |
---- |
---- |
---- |
---- |
rh |
relative humidity |
pct |
0.0 |
100.0 |
---- |
0.0 |
100.0 |
---- |
0.0 |
100.0 |
---- |
u_wind |
eastward wind component |
m/s |
-100.0 |
100.0 |
---- |
-100.0 |
100.0 |
---- |
---- |
---- |
---- |
v_wind |
northward wind component |
m/s |
-100.0 |
100.0 |
---- |
-100.0 |
100.0 |
---- |
---- |
---- |
---- |
wstat |
wind status |
none |
0.0 |
---- |
---- |
0.0 |
---- |
---- |
---- |
---- |
---- |
asc |
ascent rate |
m/s |
-10.0 |
20.0 |
5.0 |
-10.0 |
20.0 |
5.0 |
-10.0 |
20.0 |
5.0 |
An example BBSS file header (Data Object Design), which contains information on BBSS automated QC, may be found for SGP and TWP at SONDE (once there, click on "sondewnpn.b1_new") and for NSA at ISSSONDE (once there, click on "isssonde10s.a1_new").
Instrument Mentor Quality Control Checks
The BBSS Instrument Mentor (Barry Lesht) performs a number of tasks to assure the quality of BBSS data. Data quality control procedures for this system are considered mature.
QC frequency: Daily
QC delay: Real-time; weekly
QC type: Min/max/delta flags; graphical plots; mentor reviews
Inputs: Raw data files
Outputs: Hard copy plot of every sounding
Reference: None
Standard BBSS data are subject to several levels of quality control and quality assurance. The process of converting the raw 1.5-second PTU samples to values output every 2 seconds involves filtering, editing, and interpolation intended to provide the best estimate of the atmospheric state at every level. The details of the processing are not well documented. They are being analyzed by the instrument mentor and more information will be provided when it is available.
Daily logs that include operator comments regarding the system and a
listing of DQ flags set during the ingest are sent to instrument
mentor. He reviews these logs practically every day.
The mentor makes a hard-copy plot of every sounding daily. He examines the plots for features that may suggest a DQ problem that did not set one of the automatic flags. The plots also are used to verify and evaluate the DQ problems identified by the automatic procedures. If a problem is significant enough to highlight, he writes and submits a DQR for data users and submits a DQPR to site operators (SGP) to initiate corrective maintenance.
The mentor receives weekly output from the ongoing QME involving the BBSS and the microwave radiometer (MWR) (QMEMWRCOL). He processes this output to evaluate the longer- term performance of the radiosondes by comparison with the MWR, with special attention to sonde calibration lot. If it appears that a particular calibration lot may have a DQ problem, he (1) issues a request to site operations personnel to hold all remaining radiosondes from the questionable lot, (2) issues a DQR related to all soundings done using radiosondes from the questionable lot, and (3) contacts the manufacturer to arrange for special re-testing of the sondes from the questionable lot.
The mentor also does a weekly comparison of the surface values of pressure, temperature, and
humidity for each sounding with the coincident measurements obtained by the co-located
THWAPS system. These comparisons help to highlight operator data entry problems or
calibration errors. Sample comparisons (left) and sounding profiles (right) are provided below.
 |
 |
Site Scientist/Data Quality Office Quality Control Checks
The SGP Site Scientist Team and Data Quality Office extract automated flag information from BBSS files to produce tables of color-coded flag status. It also performs visual inspections of Skew-T/log p plots (from the NSDL Quicklooks web site), comparisons of sonde and 60-m tower temperature and relative humidity (CF site only), and comparison plots of THWAPS, SMOS, EBBR, and CM for temperature, humidity, and pressure (CF only). A weekly assessment report is issued to the Instrument Mentor and SGP Site Operations in which data are verified as suitable for use, or irregularities are noted. Such mentor and site scientist results then trigger the writing of appropriate DQPRs (SGP) to initiate corrective maintenance and ARM DQRs for data users.
To see these color status tables and BBSS plots, go to the SGP Data Quality Health and Status site. Once there, you will see a color status table for the present month. To see the color status for the launches of a particular day, pick a site and day, toggle "Submit Request", and this will reveal the color status tables of the launches made that day. If you place your mouse over non-green boxes, a pop-up will reveal which flags were tripped and at what percentage. Click on "Diagnostic Plot" for the launch you are interested in to see its visuals and the NSDL quicklook for the Skew-T/log p.
The NSA Site Scientist Team makes visual inspections of various sonde quicklooks and VAP-like quicklooks it has developed. For the sondes, profiles of air temperature, dewpoint temperature, relative humidity, and water vapor are produced at 10-second averages over 0-1 km and 0-10 km profiles, respectively. Total column water vapor is also derived and compared to that from the MWR to detect possible discrepancies. On-line versions of such plots can be seen from the NSA quicklook server links in "Data Quicklooks (near real-time)" below.
Two sample sonde diagnostic plots that can be found on the NSA
quicklook server are shown below, one for the 0-1 km profile (left) and
another for 0-10 km profile (right):
 |
 |
The TWP Site Scientist Team tests for missing sondes. Total column water vapor is derived and compared to that from the MWR to detect possible discrepancies. Diagnostic plots and further sonde checks are currently under construction.
Value Added Procedures and Quality Measurement Experiments
Many of the scientific needs of the ARM Program are met through the analysis and processing of existing data products into "value-added" products or VAPs. Despite extensive instrumentation deployed at the ARM CART sites, there will always be quantities of interest that are either impractical or impossible to measure directly or routinely. Physical models using ARM instrument data as inputs are implemented as VAPs and can help fill some of the unmet measurement needs of the program. Conversely, ARM produces some VAPs not in order to fill unmet measurement needs, but instead to improve the quality of existing measurements. In addition, when more than one measurement is available, ARM also produces "best estimate" VAPs. A special class of VAP called a Quality Measurement Experiment (QME) does not output geophysical parameters of scientific interest. Rather, a QME adds value to the input datastreams by providing for continuous assessment of the quality of the input data based on internal consistency checks, comparisons between independent similar measurements, or comparisons between measurement with modeled results, and so forth. For more information see:
BBSS-related VAPs include:
LSSONDE -- Produces radiosonde profiles in which the moisture profile is scaled to match MWR total precipitable water vapor.
BBSS-related QMEs include:
QMEMWRCOL -- Results from this QME are used to evaluate the MWR and radiosondes.
QMEMWRPROF -- Comparisons of retrieved water vapor and temperature profiles from mwrprof with radiosonde profiles.
QMEAERIPROF -- This QME helps to assess the ability of the radiosondes and in-situ tower measurements to observe
moisture and temperature in the atmosphere.
QMEAERILBLCLOUDS -- Uses radiosonde pressure, temperature, and moisture data as input.
Examples of Data
This information is currently unavailable.Data Quick Looks/near realtime
Quicklooks are plots of collected data, of varying sophistication. Click on the links below to see current and recent plots of BBSS data. Some plots may be intended and are more useful for operational diagnostic or educational purposes than for scientific inquiry.
- NSA
- Barrow (click on the "nsaisssonde10sC1.a1", variable, and proceed)
- SHEBA Ice Camp (click on the "BBSS" variable and proceed)
- TWP
Calibration and Maintenance
Calibration Theory
This information is currently unavailable.Calibration History
This information is currently unavailable.Maintenance Procedures
- General
General Preventative Maintenance Procedures (highlight procedure and toggle "View Procedure Summary")
- SGP
Specific SGP CF Preventative Maintenance Procedures Specific SGP BF Preventative Maintenance Procedures
Supplemental Assessment of Instrument Calibration and Maintenance Procedures
This information does not exist for BBSS.
Frequently Asked Questions FAQs
Why are BBSS data files from the NSA named differently than files from the SGP or TWP?Why don't the NSA BBSS files have any wind data?
What is RESEARCH mode?
How do I parse the sonde serial number?
How do I decode the 'Launch_Status' metadata?
What is this about a dry bias in Vaisala radiosondes?
How do ARM radiosondes differ from other radiosondes?
What is the ground check correction?
What internal processing is done to the raw data?
Why are BBSS data files from the NSA named differently than SGP and TWP files?
The BBSS system located at Barrow is an old CLASS-type (Cross-chain Loran Atmospheric Sounding System) that was originally operated by CMDL on Manus. The NSA filenames (e.g., nsaisssonde10sC1.LL.YYYYMMDD.HHMMSS) reflect this provenance. The "iss" refers to the integrated sounding system of which this unit was once a part and the "10s" refers to the fact that each sample in the output file is calculated from a 10-s window of the raw (~1.5-s) data. As in all ARM data file names, the LL indicates the data level, and the YYYYMMDD.HHMMSS have their usual meanings.
File names from the SGP and TWP are named SSSsondewXpXFF.LL.YYYYMMDD.HHMMSS. The "SSS" refers to the site identifier (SGP or TWP), the wXpX indicates the type of processing mode that was applied to the data (X={N,R}, where N is "nominal" and R is "research"), FF identifies the facility within the site (for the SGP, FF={B1,B4,B5,B6,C1,S01} and for the TWP, FF={C1,C2})
Back to FAQ
Why don't the NSA BBSS files have any wind data?
The NSA CLASS system (despite its name) was based on Omega windfinding. The Omega navigation system was turned off in September 1997 and we use PTU (pressure, temperature, humidity) only radiosondes at NSA. It is likely that a new Vaisala ground station will be installed at Barrow in FY2001 and we will start providing upper-air wind data as well.
Back to FAQ
What is RESEARCH mode?
The standard data stream output by the BBSS ground station is passed through different levels of processing by the ground station before being sent to the site data system. The ground station processing consists of filtering, editing, and interpolation. Different sets of algorithms are applied to the wind and thermodynamic data. Data treated by the standard processing algorithms (full filtering, editing, and interpolation) are termed "NOMINAL" and identified in the data file name by the letter "n" following either the "w" (for winds) or "p" (for PTU). Thus, a sounding file with nominal processing applied to both winds and thermodynamic data would be named SSSsondewnpnFF. In RESEARCH mode the only processing applied to the PTU data is an 11-s window median filter (to eliminate telemetry noise). No other processing (including radiation correction of the temperature) is done. For winds, no editing, filtering, or interpolation is done in RESEARCH mode. The standard processing mode for SGP soundings up until 11/24/2000 was wrpn. Since 11/24/2000 we have been using wnpn processing modes for SGP soundings (see BCR-00304 for further discussion).
Back to FAQ
How do I parse the sonde serial number?
The radiosonde serial numbers are assigned when the sensor packs are calibrated. The numbers encode the date of calibration as well as other information. Prior to October 1995, the serial number code (for RS-80s) was:
DDMMYTTPP, in whichBack to FAQ
DD = day of the month (1-31) MM = month (1-12) + facility identifier (00, 20, 40, or 80) Y = last digit of the year TT = calibration tray identifier PP = position in calibration tray
More recent radiosonde serial numbers are coded
YWWDTTTNN, in which
Y = last digit of the year WW = week number (1-52) D = day of the week (1-7) Monday=1 TTT = calibration tray identifer NN = position in calibration tray
RS-90 radiosondes (used operationally by ARM at SGP since 5/1/2001) are coded
YWWDSSSS, in which
Y = alphabetic code for the year (T=1998, U=1999, etc.) WW = week number (1-52) D = day of the week (1-7) Monday=1 SSSS = sequence number
How do I decode the 'Launch Status' metadata?
The Launch Status word is coded as follows:Back to FAQ
SmSmSmSmSmSmSmSmSmSm NNNNNNNNNNNNNNN IIiii YrYrMoMoDaDa HrHrMnMn SnSnSnSnSnSnSnSnSn PcoPcoPco TcoTcoTco UcoUcoUco ChnChnChn PacPacPac PmdPmdPmd PrjPrjPrj TacTacTac TmdTmdTmd TrjTrjTrj UacUacUac UmdUmdUmd UrjUrjUrj PmiPmiPmi TmiTmiTmi UmiUmiUmi TiTiTi RRR HeHeHe AoAoAo BoBoBo CoCoCo DoDoDo EoEoEo FoFoFo GoGoGo HoHoHo aoaoao bobobo cococo
Where:
SmSmSm... sounding number NNN... station name II WMO block number iii international station number YrYrMoMoDaDa date of sounding HrHrMnMn time of balloon release SnSnSn... radiosonde serial number PcoPcoPco ground check correction for pressure in tenths of a hPa TcoTcoTco ground check correction for temperature in tenths of a degC UcoUcoUco ground check correction for humidity in %RH ChnChnChn percentage of successful attempts to identify signal sequence PacPacPac accepted levels of P (%) PmdPmdPmd replaced levels of P (%) PrjPrjPrj rejected levels of P (%) TacTacTac TmdTmdTmd as for P TrjTrjTrj UacUacUac UmdUmdUmd as for P, T UrjUrjUrj PmiPmiPmi maximum interpolated layer in 10 TmiTmiTmi second units for PTU profiles UmiUmiUmi TiTiTi duration of ascent in 10 second units RRR reason for termination 001 stop command 004 maximum interpolation time of pressure or temperature exceeded 005 increasing pressure 006 prelaunch set limite exceeded 010 no PTU signal HeHeHe altitude reach in units of 100m
For Loran soundings (SGP)
AoAoAo station in wind calculations (%) BoBoBo Master stations are AoAoAo and ... GoGoGo. Others are slave stations HoHoHo ... cococo
For GPS soundings (TWP)
AoAoAo percentage of valid raw wind levels BoBoBo percentage of valid raw wind levels which have at least 5 satellites in track CoCoCo percentage of valid raw wind levels which have at leave 4 satellites in track DoDoDo percentage of raw wind levels rejected due to poor PDOP EoEoEo percentage of raw wind levels which have unidentified channel in solution FoFoFo not used GoGoGo 10*mean track count of all levels HoHoHo 10*mean track count of valid levels aoaoao cumulative minutes of long (>1min) time gaps bobobo not used cococo not used
What is this about "dry bias" in Vaisala radiosondes?
Since the beginning of the program, ARM has conducted ongoing data quality studies involving comparisons among different instruments. One of the oldest of these compares the precipitable water vapor (PWV) retrieved, from the CART microwave radiometer (MWR) with the PWV calculated from the radiosonde soundings. Over the years these comparisons have helped to detect problems with both these and other CART instruments. After collecting years of data it became apparent that sequences of radiosonde launches showed lower PWV than the MWR. At first this finding was thought to be due to batch-to-batch calibration variations. Indeed ARM discovered that a large batch of Vaisala radiosondes were incorrectly calibrated in November 1994 (see DQR960229.1).
More recent work has shown that the batch-to-batch variability in RH results from contamination of the humidity sensor by organic vapors originating in the plastic parts of the radiosonde. The effect of the contamination is to reduce the number of polymer binding sites available for water vapor and thus bias the sensor output low. A Problem Identification Report (PIF990129.5) describing the bias problem has been filed.
Vaisala has developed a proprietary processing algorithm that is supposed to correct the radiosonde data for the dry bias. The problem and the algorithm is described in some detail in two papers that were presented at the 1999 ARM Science Team meeting. PDF versions of these papers are available by clicking the links below:
Lesht, B.M. 1999. Reanalysis of radiosonde data from the 1996 and 1997 water vapor intensive operations periods: Application of the Vaisala RS-80 contamination correction algorithm.
Miller, E.R., J. Wang, and H.R. Cole. 1999. Correction for dry bias in Vaisala radiosonde RH data.
Back to FAQ
Software Documentation for this Instrument
ARM netCDF file header descriptions may be found for BBSS at SGP and TWP at Sonde and for NSA at ISSSonde.
Contacts
Instrument Mentor
Barry M. LeshtAssociate Division Director
Environmental Research Division
Argonne National Laboratory
9700 South Cass Avenue
Argonne, IL 60439
Phone: (630)252-4208
Fax: (630)252-2959
bmlesht@anl.gov
Vendor/Instrument Developer
Vaisala, Inc.100 Commerce Way
Woburn, MA 01801
Phone: (617)933-4500
Fax: (617)933-8029
www.vaisala.com
Glossary
ARM GlossaryAcronyms
ARM Acronyms and AbbreviationsCitable References
Lesht, B.M., 1995: "An Evaluation of ARM Radiosonde Operational Performance." Proceedings of the Ninth Symposium on MeteorologicalObservations and Instrumentation, American Meteorological Society, Boston, MA. pp. 6-10.
Lesht, B.M., and J.C. Liljegren, 1996: "Comparison of Precipitable Water Vapor Measurements Obtained by Microwave Radiometry
and Radiosondes at the Southern Great Plains CART site." Proceedings of the Sixth ARM Science Team Meeting, San Antonio, TX
