This data set is a composite of radiosondes and dropsondes collected from 3 dropsonde and
4 radiosonde platforms (see Section 2.3) during the Pre-Depression INvestigation of Cloud-systems
in the Tropics (PREDICT) 2010 project with data collected from 1 August 2010 through 30 September 2010.
The PREDICT area of interest is 0 to 45N and 15-100W. This composite contains a total of 3219 soundings
at their native resolution.
Included are radiosonde data from the GTS Mandatory/Significant Level Sounding Data (1287 radiosondes),
Howard University at Barbados (99 radiosondes), Howard University at Cape Verde (20 radiosondes),
and from 24 US National Weather Service sites (841 radiosondes). Additionally, dropsonde data are
included from the United States Air Force C-130 (86 dropsondes), NSF/NCAR G-V (558 dropsondes),
and GRIP NASA DC-8 (328 dropsondes).
All soundings are provided at the highest possible resolution (i.e., the 'native' resolution) and were quality
controlled by NCAR/EOL. Data are available in the NCAR/EOL Sounding Composite Format (columnar ASCII).
Version 2 of this data set was released in March 2017. See Section 2.3 for details on the changes.
Scot Loehrer
NCAR/EOL
loehrer@ucar.edu
All upper air soundings were converted to National Center for Atmospheric Research/Earth Observing Laboratory (NCAR/EOL) Sounding Composite Format (ESC). ESC is a version of the National Center for Atmospheric Research (NCAR) CLASS format and is an ASCII format consisting of 15 header records for each sounding followed by the data records with associated QC information.
The header records (15 total records) contain data type, project ID, site ID, site location, release time, sonde type, meteorological and wind data processors. The first five header lines contain information identifying the sounding, and have a rigidly defined form. The following 7 header lines are used for auxiliary information and comments about the sounding, and may vary from dataset to dataset. The last 3 header records contain header information for the data columns. Line 13 holds the field names, line 14 the field units, and line 15 contains dashes ('-' characters) delineating the extent of the field.
The five standard header lines are as follows:
| Line | Label (padded to 35 char) | Contents |
|---|---|---|
| 1 | Data Type: | Description of type and resolution of data. |
| 2 | Project ID: | Id of weather project. |
| 3 | Release Site Type/Site ID: | Description of the release site. |
| 4 | Release Location (lon,lat,alt): | Position of release site in the format described below. |
| 5 | UTC Release Time (y,m,d,h,m,s): | Time of release, in the format: yyyy, mm, dd, hh:mm:ss |
The release location is given as: lon (deg min), lat (deg min), lon (dec. deg), lat (dec. deg), alt (m)
Longitude in deg min is in the format: ddd mm.mm'W where ddd is the number of degrees from True North (with leading zeros if necessary), mm.mm is the decimal number of minutes, and W represents W or E for west or east longitude, respectively. Latitude has the same format as longitude, except there are only two digits for degrees and N or S for north/south latitude. The decimal equivalent of longitude and latitude and station elevation follow.
The seven non-standard header lines may contain any label and contents. The labels are padded to 35 characters to match the standard header lines. Records for this dataset include variable information depending on the data source.
All do contain at a minimum:| Line | Label (padded to 35 char) | Contents |
|---|---|---|
| 6 | ||
| 7 | ||
| 8 | ||
| 9 | ||
| 10 | ||
| 11 | ||
| 12 | Nominal Release Time (y,m,d,h,m,s): | Nominal time of release, in the format: yyyy, mm, dd, hh:mm:ss |
The data records each contain time from release, pressure, temperature, dew point, relative humidity, U and V wind components, wind speed and direction, ascent rate, balloon position data, altitude, and quality control flags (see the QC code description). Each data line contains 21 fields, separated by spaces, with a total width of 130 characters. The data are right-justified within the fields. All fields have one decimal place of precision, with the exception of latitude and longitude, which have three decimal places of precision. The contents and sizes of the 21 fields that appear in each data record are as follows:
| Field No. | Width | Format | Parameter | Units | Missing Value |
|---|---|---|---|---|---|
| 1 | 6 | F6.1 | Time | Seconds | 9999.0 |
| 2 | 6 | F6.1 | Pressure | Millibars | 9999.0 |
| 3 | 5 | F5.1 | Dry-bulb Temperature | Degrees C | 999.0 |
| 4 | 5 | F5.1 | Dew Point Temperature | Degrees C | 999.0 |
| 5 | 5 | F5.1 | Relative Humidity | Percent | 999.0 |
| 6 | 6 | F6.1 | U Wind Component | Meters / Second | 9999.0 |
| 7 | 6 | F6.1 | V Wind Component | Meters / Second | 9999.0 |
| 8 | 5 | F5.1 | Wind Speed | Meters / Second | 999.0 |
| 9 | 5 | F5.1 | Wind Direction | Degrees | 999.0 |
| 10 | 5 | F5.1 | Ascent Rate | Meters / Second | 999.0 |
| 11 | 8 | F8.3 | Longitude | Degrees | 9999.0 |
| 12 | 7 | F7.3 | Latitude | Degrees | 999.0 |
| 13 | 5 | F5.1 | Elevation Angle | Degrees | 999.0 |
| 14 | 5 | F5.1 | Azimuth Angle | Degrees | 999.0 |
| 15 | 7 | F7.1 | Altitude | Meters | 99999.0 |
| 16 | 4 | F4.1 | QC for Pressure | Code (see below) | 99.0 |
| 17 | 4 | F4.1 | QC for Temperature | Code (see below) | 99.0 |
| 18 | 4 | F4.1 | QC for Humidity | Code (see below) | 99.0 |
| 19 | 4 | F4.1 | QC for U Wind Component | Code (see below) | 99.0 |
| 20 | 4 | F4.1 | QC for V Wind Component | Code (see below) | 99.0 |
| 21 | 4 | F4.1 | QC for Ascension Rate | Code (see below) | 99.0 |
Fields 16 through 21 contain the Quality Control information derived at the NCAR Earth Observing Laboratory (NCAR/EOL). Any QC information from the original sounding is replaced by the following EOL codes:
| Code | Description |
|---|---|
| 99.0 | Unchecked (QC information is "missing.") ("UNCHECKED") |
| 1.0 | Checked, datum seems physically reasonable. ("GOOD") |
| 2.0 | Checked, datum seems questionable on physical basis. ("MAYBE") |
| 3.0 | Checked, datum seems to be in error. ("BAD") |
| 4.0 | Checked, datum is interpolated. ("ESTIMATED") |
| 9.0 | Checked, datum was missing in original file. ("MISSING") |
The following is a sample record of PREDICT 2010 radiosonde data in ESC format. The data portion is much longer than 80 characters and, therefore, wraps around to a second line. See section 2.1 for an exact format specification
Data Type: National Weather Service Sounding/Ascending Project ID: PREDICT_2010 Release Site Type/Site ID: KKEY Key West, FL / 72201 Release Location (lon,lat,alt): 081 47.32'W, 24 33.18'N, -81.789, 24.553, 13.0 UTC Release Time (y,m,d,h,m,s): 2010, 08, 16, 23:05:40 Ascension Number: 446 Radiosonde Serial Number: 85155425 Balloon Manufacturer/Type: Totex / GP26 Balloon Lot Number/Weight: 32010 / 0.700 Radiosonde Type/RH Sensor Type: Sippican Mark IIA with chip thermistor, pressure / Sippican Mark IIA Carbon Hygristor Surface Observations: P: 1012.0, T: 999.0, RH: 58.0, WS: 2.6, WD: 163.0 Nominal Release Time (y,m,d,h,m,s):2010, 08, 17, 00:00:00 Time Press Temp Dewpt RH Ucmp Vcmp spd dir Wcmp Lon Lat Ele Azi Alt Qp Qt Qrh Qu Qv QdZ sec mb C C % m/s m/s m/s deg m/s deg deg deg deg m code code code code code code ------ ------ ----- ----- ----- ------ ------ ----- ----- ----- -------- ------- ----- ----- ------- ---- ---- ---- ---- ---- ---- 0.0 1012.0 31.0 22.1 59.0 -1.3 1.6 2.1 140.9 999.0 -81.789 24.553 999.0 999.0 13.0 1.0 1.0 1.0 1.0 1.0 9.0 1.0 1011.7 30.9 22.1 59.4 -0.8 1.4 1.6 150.3 3.0 -81.789 24.553 999.0 999.0 16.0 1.0 3.0 3.0 1.0 1.0 99.0 2.0 1011.1 30.9 22.2 59.7 -0.8 1.4 1.6 150.3 5.0 -81.789 24.553 999.0 999.0 21.0 1.0 3.0 3.0 1.0 1.0 99.0 3.0 1010.6 30.8 22.2 60.1 -0.8 1.5 1.7 151.9 5.0 -81.789 24.553 999.0 999.0 26.0 1.0 3.0 3.0 1.0 1.0 99.0 4.0 1010.0 30.7 22.2 60.5 -0.9 1.5 1.7 149.0 5.0 -81.789 24.553 999.0 999.0 31.0 1.0 3.0 3.0 1.0 1.0 99.0 5.0 1009.3 30.7 22.3 60.8 -0.9 1.6 1.8 150.6 6.0 -81.789 24.553 999.0 999.0 37.0 1.0 3.0 3.0 1.0 1.0 99.0 6.0 1008.7 30.6 22.3 61.2 -1.0 1.6 1.9 148.0 5.0 -81.789 24.553 999.0 999.0 42.0 1.0 3.0 3.0 1.0 1.0 99.0 7.0 1008.1 30.5 22.3 61.6 -1.0 1.6 1.9 148.0 6.0 -81.789 24.553 999.0 999.0 48.0 1.0 3.0 3.0 1.0 1.0 99.0 8.0 1007.4 30.5 22.4 61.9 -1.1 1.6 1.9 145.5 6.0 -81.789 24.553 999.0 999.0 54.0 1.0 3.0 3.0 1.0 1.0 99.0 9.0 1006.8 30.4 22.4 62.3 -1.1 1.6 1.9 145.5 5.0 -81.789 24.553 999.0 999.0 59.0 1.0 3.0 3.0 1.0 1.0 99.0 10.0 1006.2 30.3 22.4 62.7 -1.2 1.6 2.0 143.1 6.0 -81.789 24.553 999.0 999.0 65.0 1.0 3.0 3.0 1.0 1.0 99.0 11.0 1005.6 30.3 22.5 63.0 -1.2 1.6 2.0 143.1 5.0 -81.789 24.553 999.0 999.0 70.0 1.0 3.0 3.0 1.0 1.0 99.0 12.0 1005.0 30.2 22.5 63.4 -1.2 1.6 2.0 143.1 6.0 -81.789 24.553 999.0 999.0 76.0 1.0 3.0 3.0 1.0 1.0 99.0 13.0 1004.4 30.1 22.5 63.7 -1.3 1.6 2.1 140.9 5.0 -81.789 24.553 999.0 999.0 81.0 1.0 3.0 3.0 1.0 1.0 99.0 14.0 1003.8 30.1 22.6 64.1 -1.3 1.6 2.1 140.9 6.0 -81.789 24.553 999.0 999.0 87.0 1.0 3.0 3.0 1.0 1.0 99.0 15.0 1003.2 30.0 22.6 64.5 -1.3 1.6 2.1 140.9 5.0 -81.789 24.553 999.0 999.0 92.0 1.0 3.0 3.0 1.0 1.0 99.0 : : :
None.
2.3.1 Howard University Barbados Radiosonde Data
The Howard University Barbados Sounding Data includes 99 high vertical
resolution (4 second) soundings from Barbados taken by Howard University
from 14 August through 25 September 2010. This station utilized Graw radiosondes,
either the DFM-06 or DFM-97 type. There are four sondes where the
sonde type was not available. The header records for each sonde specify the sonde type.
This data underwent an automated QC process. The dataset underwent
internal consistency checks which included two types of checks, gross limit
checks on all parameters and rate-of-change checks on temperature, pressure and
ascension rate. Some further information on the QC processing conducted by
NCAR/EOL can be found either in the readme documentation for
Howard University High Resolution Soundings - Barbados
here or in Loehrer et al. (1996) and Loehrer et al. (1998).
Version 2.0 of this data set was released in February 2017. In this version a dry bias
in the RD94 relative humidity measurements was corrected. The dry bias was strongly
temperature dependent, being considered quite small at warm temperature and more substantial
at cold temperatures. More complete information on the origin, magnitude, and impact of the
bias is available in an NCAR Technical Note (Voemel, et al 2016):
http://dx.doi.org/10.5065/D6XS5SGX.
This correction was applied to all of the NSF/NCAR G-V and NASA DC-8 dropsonde data. Only
six of the USAF C-130 dropsondes were impacted by this bias and those six were corrected. The remaining
USAF C-130 dropsondes were all the older RSS903 dropsondes and were not affected by this bias. All of
the dropsondes that have had the correction applied have the following text within the "Post Processing
Comments" header record: TDDryBiasCorrApplied.
All of the radiosonde data remain the same as Version 1.0.
| ID | SITE | LONG | LAT | ELEV (m) |
|---|---|---|---|---|
| Howard University | Barbados | -59.60000 | 13.10000 | 112.8 |
| Howard University | Barbados | -59.62500 | 13.14900 | 112.8 |
2.3.2 Howard University Cape Verde Radiosonde Data
This data includes 20 high vertical resolution (2 second) soundings
from Cape Verde taken by Howard University from 27 August through 15 September 2010.
The station utilized Graw radiosondes, either the DFM-06 or DFM-97 type. There are three sondes where the
sonde type was not available. The header records for each sonde specify the sonde type.
This data underwent an automated QC process. The dataset underwent
internal consistency checks which included two types of checks, gross limit
checks on all parameters and rate-of-change checks on temperature, pressure and
ascension rate. Some further information on the QC processing conducted by
NCAR/EOL can be found either in the readme documentation for
Howard University High Resolution Soundings - Cape Verde
here or in Loehrer et al. (1996) and Loehrer et al. (1998).
| ID | SITE | LONG | LAT | ELEV (m) |
|---|---|---|---|---|
| Howard University | Cape Verde | -24.867 | 16.864 | 10.0 |
2.3.3 USAF C-130 Dropsonde Data
The United States Air Force C-130 aircraft dropsonde data includes 86 high resolution dropsonde data files from the USAF C-130 aircraft that flew over the Atlantic basin and Gulf of Mexico during PREDICT. Data are included from thirteen flights that occurred 31 August to 29 September 2010. For more information regarding the data, go here
| ID | Site/Platform | State/Country | Longitude | Latitude | Elevation (m) |
|---|---|---|---|---|---|
| AF302/AF303/AF306/AF308/AF309 | USAF Lockheed C-130J | N/A | Mobile | Mobile | -9999.9 |
2.3.4 NSF/NCAR G-V Dropsonde Data
The NSF/NCAR G-V aircraft data includes 558 dropsondes released over the Altantic basin during the months of August and September 2010. For more details on this dataset, go here
| ID | Site/Platform | State/Country | Longitude | Latitude | Elevation (m) |
|---|---|---|---|---|---|
| N677F | NSF/NCAR GV | N/A | Mobile | Mobile | -9999.9 |
2.3.5 GRIP NASA DC-8
The GRIP NASA DC-8 aircraft data includes 328 dropsondes collected during the GRIP NASA DC-8 flights for the Genesis and Rapid Intensification Process (GRIP) experiment. For more details on this dataset, go here
| ID | Site/Platform | State/Country | Longitude | Latitude | Elevation (m) |
|---|---|---|---|---|---|
| N817NA | NASA DC-8 | N/A | Mobile | Mobile | -9999.9 |
2.3.6 GTS Mandatory/Significant Level Sounding Data
The GTS Mandatory/Significant Level Sounding Data includes 1287 GTS mandatory and significant level soundings from 24 stations in the Carribean and Gulf of Mexico region for the period 15 August 2010 to 30 September 2010. Stations typically released soundings at 00 and or 12 UTC.
The GTS Mandatory/Significant Level Sounding dataset underwent an automated QC process. The dataset underwent internal consistency checks which included two types of checks, gross limit checks on all parameters and rate-of-change checks on temperature, pressure and ascension rate. Some further information on the QC processing conducted by NCAR/EOL can be found in the readme documentation for the GTS Mandatory/Significant Level Sounding Data set here and in Loehrer et al. (1996) and Loehrer et al. (1998).
| ID | SITE | STATE | LON | LAT | ELEV (m) |
|---|---|---|---|---|---|
| GQPP | 61415 | NOUADHIBOU MAURITANIA | -17.030 | 20.930 | 3.0 |
| GQNN | 61442 | NOUAKCHOTT MAURITANIA | -15.950 | 18.100 | 3.0 |
| GOOY | 61641 | DAKAR/YOFF SENEGAL | -17.500 | 14.730 | 24.0 |
| CUN | 76595 | Cancun Mexico | -86.850 | 21.030 | 5.0 |
| MID | 76644 | Merida Mexico | -89.650 | 20.950 | 11.0 |
| MEX | 76679 | Mexico City Mexico | -99.070 | 19.430 | 2309.0 |
| VER | 76692 | Veracruz Mexico | -96.120 | 19.170 | 13.0 |
| XXX | 76805 | Acapulco Mexico | -99.930 | 16.050 | 3.0 |
| YNN | 78073 | Nassau Bahamas | -77.470 | 25.050 | 2.0 |
| KCR | 78384 | George Town Cayman Islands | -81.370 | 19.300 | 3.0 |
| KJP | 78397 | Kingston Jamaica | -76.780 | 17.930 | 1.0 |
| SDQ | 78486 | Santo Domingo Dominican Republic | -69.880 | 18.470 | 14.0 |
| ZBZ | 78583 | Belize | -88.300 | 17.530 | 5.0 |
| XXX | 78807 | Corozal Oeste Panama | -79.660 | 8.970 | 9.0 |
| ACM | 78866 | St. Maarten | -63.120 | 18.050 | 3.0 |
| FFR | 78897 | Le Raizet Guadeloupe | -61.520 | 16.270 | 8.0 |
| BDI | 78954 | Barbados | -59.500 | 13.070 | 47.0 |
| ACC | 78988 | Curacao | -68.970 | 12.200 | 54.0 |
| XXX | 80001 | San Andres Island Colombia | -81.700 | 12.580 | 4.0 |
| SKRH | 80035 | Riohacha Colombia | -72.930 | 11.530 | 4.0 |
| SKBO | 80222 | Bogota Colombia | -74.130 | 4.700 | 2548.0 |
| SOCA | 81405 | Rochambeau Guyana | -52.370 | 4.830 | 9.0 |
| SBBV | 82022 | Boa Vista Brazil | -60.700 | 2.830 | 140.0 |
| XXX | 82099 | Monte Dourado Brazil | -51.070 | 0.050 | 17.0 |
2.3.7 National Weather Service (NWS) Soundings
This data set includes 841 high vertical resolution (1-second)
Radiosonde Replacement System (RRS) soundings from National
Weather Service (NWS) rawinsonde stations. For PREDICT this data set
includes data from 1 August 2010 through 30 September 2010 for six (6)
NWS stations (Key West, FL, Miami, FL, Tampa Bay, FL, Brownsville, TX,
Corpus Christi, TX, and San Juan, Puerto Rico). At the request of GRIP
investigators this data set also includes data from 1 September 2010
through 5 September 2010 for seven (7) stations along the east coast
of the United States (Jacksonville, FL, Charleston, SC, Newport, NC,
Sterling, VA, Upton, NY, Chatham, MA, and Gray, ME) for Hurricane Earl.
The soundings were typically released twice a day (0000 and 1200 UTC) and
any special releases are also included.
The detailed description of the NWS Radiosonde Replacement System (RRS)
sounding collection and instrumentation is located in
http://www.ua.nws.noaa.gov/RRS.htm
These soundings utilized the Global Positioning System (GPS) to derive the winds.
NCAR/EOL did no additional processing to the wind data provided in these soundings.
NCAR/EOL utilized the processed version of the RRS data. This means the data were
smoothed and had corrections applied (e.g. solar radiation correction) by the NWS.
NCAR/EOL conducted no additional processing to the data values. However,
additional quality assurance was applied as described in the documentation for the
National Weather Service High Resolution Radiosonde Data (ESC Format) documentation.
ID SITE STATE COUNTRY LAT LONG ELEV (m) SONDE TYPE ------------------------------------------------------------------------- TJSJ San Juan -- PR 18.4 -66.0 3.0 Sippican Mark IIA KCHH Chatham MA US 41.7 -70.0 15.0 Sippican Mark IIA KCHS Charleston SC US 32.9 -80.0 13.0 Sippican Mark IIA KGYX Gray (Portland) ME US 43.9 -70.3 124.0 Sippican Mark IIA KIAD Sterling VA US 39.0 -77.5 88.0 Sippican Mark IIA KJAX Jacksonville FL US 30.5 -81.7 10.0 Sippican Mark IIA KMHX Newport NC US 34.8 -76.9 11.0 Sippican Mark IIA KOKX Upton-Brookhaven NY US 40.9 -72.9 20.0 Sippican Mark IIA KBRO Brownsville TX US 25.9 -97.4 7.0 Sippican Mark IIA KCRP Corpus Christi TX US 27.8 -97.5 15.0 Sippican Mark IIA KKEY Key West FL US 24.6 -81.8 13.0 Sippican Mark IIA KMIA Miami FL US 25.8 -80.4 4.0 Sippican Mark IIA KTBW Tampa Bay FL US 27.7 -82.4 13.0 Sippican Mark IIA
Loehrer, S. M., T. A. Edmands, and J. A. Moore, 1996: TOGA COARE upper-air sounding data archive: development and quality control procedures. Bull. Amer. Meteor. Soc., 77, 2651-2671.
Loehrer, S. M., S. F. Williams, and J. A. Moore, 1998: Results from UCAR/JOSS quality control of atmospheric soundings from field projects. Preprints, Tenth Symposium on Meteorological Observations and Instrumentation, Phoenix, AZ, Amer. Meteor. Soc., 1-6.