FASTEX High Resolution Upper-Air Sounding Composite Data Set 1.0 Dataset Overview This data is a composite upper-air sounding data set which consists of all FASTEX upper-air sounding data collected from 45 sounding platforms. The data in the composite is at the highest possible resolution (i.e. the `native' resolution). 2.0 Detailed Dataset Description All data within this composite has passed through the two-stage JOSS FASTEX sounding quality control (QC) procedure. The first stage was a set of automated internal consistency checks. Second, was a visual examination of each sounding (see Section 4.0). For more complete information on the original data, the JOSS processing, and more detailed information on the QC processing conducted at any of the platforms, please see the individual site documentation available on-line. All soundings within this dataset have been converted to a standard format (see Section 3.0) and completely quality controlled. Each site can have different vertical resolutions, typical release times, available dates, as well as radiosonde and windfinding system types. For more detailed information please see the individual site documentation avaialble on CODIAC for each individual platform. 3.0 JOSS CLASS Format (ASCII text) Description 3.1 Header records The header records (15 total records) contain data type, project ID, site ID, site location, actual release time, nominal release time, and possibly other specialized information. The first five header lines contain information identifying the sounding, and have a rigidly defined form. The following 6 header lines are used for auxiliary information and comments about the sounding, and they vary significantly from data set to data set. The next line (line 12) contains the Nominal date and time of the release. 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 six standard header lines are as follows: Line Label (fixed to 35 char in length) Contents 1 Data Type: Description of type and resolution of data. 2 Project ID: ID of weather project. 3 Launch Site Type/Site ID: Description of launch site. 4 Launch Location (lon,lat,alt): Position of launch site, in format described below. 5 UTC Launch Time: Time of release, in format: yyyy, mm, dd, hh:mm:ss 12 UTC Nominal Launch Time: Nominal release time. The launch site type/site ID has the format: site ID (three or four letter code), the full site name, the country code and the WMO code for the site. 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 six non-standard header lines may contain any label and contents. The label is fixed to 35 characters to match the standard header lines. Sample header records are provided in the sample data file in section 3.3. 3.2 Data records 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 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 Format Missing No. Width Parameter Units 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 Ascension 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 Variable (see below) 999.0 14 5 F5.1 Variable (see below) 999.0 15 7 F7.1 Altitude Meters 99999.0 16 4 F4.1 QC flag for Pressure Code (see below) 99.0 17 4 F4.1 QC flag for Temperature Code (see below) 99.0 18 4 F4.1 QC flag for Humidity Code (see below) 99.0 19 4 F4.1 QC flag for U Component Code (see below) 99.0 20 4 F4.1 QC flag for V Component Code (see below) 99.0 21 4 F4.1 QC flag for Ascension Rate Code (see below) 99.0 ---------------------------------------------------------------------- Fields 13 and 14 are `variable' because depending on the sounding system the variables used in these positions can vary. Fields 16 through 21 contain the Quality Control information (flags) generated locally at JOSS. These flags are based on the automated or visual checks made. See Sections 6.0 and 7.0 for further information. The JOSS QC flags are as follows: 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') ---------------------------------------------------------------------- 3.3 Sample data The following is a sample portion of a JOSS CLASS format file including header records. The data portion is much longer than 80 characters and, therefore, wraps around to a second line. Data Type: Sounding Project ID: FASTEX class format UKMET high resolution sounding Launch Site Type/Site ID: ABE Aberporth, UK, 03502 Launch Location (lon,lat,alt): 004 34.20'W, 52 7.80'N, -4.57, 52.13, 121.0 GMT Launch Time (y,m,d,h,m,s): 1997, 01, 10, 14:07:00 / / / / / / Nominal Launch Time (y,m,d,h,m,s): 1997, 01, 10, 15:00:00 Time Press Temp Dewpt RH Uwind Vwind Wspd Dir dZ Lon Lat Rng Ang Alt Qp Qt Qh Qu Qv Qdz sec mb C C % m/s m/s m/s deg m/s deg deg km deg m code code code code code code ------ ------ ----- ----- ----- ------ ------ ----- ----- ----- -------- ------- ----- ----- ------- ---- ---- ---- ---- ---- ---- 0.0 1001.3 0.9 -2.3 79.0 -3.0 5.2 6.0 150.0 999.0 -4.570 52.130 999.0 999.0 121.0 1.0 1.0 1.0 1.0 1.0 99.0 2.0 1000.7 0.9 -2.5 78.0 -3.2 5.7 6.5 151.0 2.0 -4.570 52.130 999.0 999.0 125.0 1.0 1.0 1.0 1.0 1.0 99.0 4.0 1000.4 0.9 -2.7 77.0 -3.2 6.0 6.8 152.0 1.0 -4.570 52.130 999.0 999.0 127.0 1.0 1.0 1.0 1.0 1.0 99.0 4.0 Quality Control Procedures This dataset underwent the JOSS QC process which consisted of internal consistency checks and visual quality control. The internal consistency checks included gross limit checks on all parameters and vertical consistency checks on temperature, pressure, and ascension rate. JOSS then visually examined each sounding. 4.1 Automated Quality Control Procedures 4.1.1 Gross Limit Checks These checks were conducted on each sounding and data were automatically flagged as appropriate. Only the data point under examination was flagged. JOSS conducted the following gross limit checks on most of the FASTEX sounding data set. The only changes where that some site had different allowable temperature increases (inversions). In the table P = pressure, T = temperature, RH = relative humidity, U = U wind component, V = V wind component, B = bad, and Q = questionable. ---------------------------------------------------------------- Parameter(s) Flag Parameter Gross Limit Check Flagged Applied ---------------------------------------------------------------- Pressure < 0 mb or > 1050 mb P B Altitude < 0 m or > 40000 m P, T, RH Q Temperature < -80C or > 30C T Q Dew Point < -99.9C or > 25C RH Q > Temperature T, RH Q Relative Humidity < 0% or > 100% RH B Wind Speed < 0 m/s or > 100 m/s U, V Q > 150 m/s U, V B U Wind Component < 0 m/s or > 100 m/s U Q > 150 m/s U B V Wind Component < 0 m/s or > 100 m/s V Q > 150 m/s V B Wind Direction < 0 deg or > 360 deg U, V B Ascent Rate < -10 m/s or > 10 m/s P, T, RH Q ---------------------------------------------------------------- 4.1.2 Vertical Consistency Checks These checks were conducted on each sounding and data were automatically flagged as appropriate. These checks were started at the lowest level of the sounding and compared neighboring six-second average values. In the case of checks ensuring that the values increased/decreased as expected, only the data point under examination was flagged. However, for the other checks, all of the data points used in the examination were flagged. All items within the table are as previously defined. ---------------------------------------------------------------- Vertical Consistency Parameter(s) Flag Parameter Check Flagged Applied ---------------------------------------------------------------- Time decreasing/equal None None Altitude decreasing/equal P, T, RH Q Pressure increasing/equal P, T, RH Q > 1 mb/s or < -1 mb/s P, T, RH Q > 2 mb/s or < -2 mb/s P, T, RH B Temperature < -15 C/km P, T, RH Q < -30 C/km P, T, RH B from surface to 800 mb: > 25 C/km (not applied at p < 275mb) P, T, RH Q > 40 C/km (not applied at p < 275mb) P, T, RH B for pressures < 800 mb: > 5 C/km (not applied at p < 275mb) P, T, RH Q > 30 C/km (not applied at p < 275mb) P, T, RH B Ascent Rate change of > 3 m/s or < -3 m/s P Q change of > 5 m/s or < -5 m/s P B ---------------------------------------------------------------- 4.2 Visual Quality Control Procedures Each sounding was then visually examined for problems that were not able to be captured via the automated checks described in item 6.1 above. These problems typically included oddities in the dew point and wind profiles. These two parameters can be highly variable, and hence, the automated checking is more difficult. The visual checking procedure has two main purposes: First, as a check on the results provided by the automatic checks, and second, as a more stringent check on the more variable parameters. 5.0 FASTEX Data Use According to the FASTEX data policy, the use of these data is unrestricted for research and educational purposes. Proper acknowledgements should be given in publications that utilize this data to specific scientists and institutions that made the collection of data possible. Where appropriate, all authors considering publication of FASTEX related research results should offer co-authorship to investigators that had a primary role in the collection of data utilized in the study. 6.0 Upper-Air Sounding Data Providers FASTEX Land-Based Upper-Air Sounding Data Providers Country Name Address -------- ---------------- -------------------------------------------------- Canada Dave Steenbergen AES 4905 Dufferin Street Downsview Ontario M3H 5T4 Denmark Klaus Hedegaard DMI Lyngbyveg 100 DK-2100 France Michel Rochas Meteo-France Instrumentation Dept. 7,rue Teisserenc de Bort BP202 78195 Trappes Iceland Flosi Sigurosson Meteorological Office Technical and Obs. Dept Bustadavegur 9 IS-140 Reykjavik Ireland Liam Burke Meteorological Office Instrumentation and Environmental Division Glasnevin Hill Dublin 9 Portugal Renato Carvalho INMG Rua C. Aeroporto de Lisboa 1700 Lisboa Spain Cesar Belandia INM Servicio de Observacion, Camino de la Moreras s/n Ciudad Universitaria 28071 MADRID United John Stancombe UK Met Office Upper Air Network Kingdom London Road Bracknell, Berkshire RG12 2SZ USA Robert Thomas NOAA W/OSO14 SSMC/2 1325 East West Highway Silver Spring,MD 20910 FASTEX Aircraft Dropsonde Data Providers Aircraft Name Address -------- -------------- ---------------------------------- LEAR36 Dean Lauritsen NCAR/ATD P.O. Box 300 Boulder,CO 80307 USA (lauritsn@ucar.edu) US-C1307 Jon Talbot 53rd Weather Reconnaissance Squadron, US-C1308 Keelser Air Force Base Mississippi, USA (info@hurricanehunters.com) NOAA-GIV John Daugherty NOAA/NSSL 325 Broadway Boulder,CO 80303 USA (johnd@ncar.ucar.edu) NOAA-P3 David Jorgensen NOAA/NSSL 325 Broadway Boulder,CO 80303 USA (davej@ncar.ucar.edu) UK-C130 Sid Clough Joint Centre for Mesoscale Meteorology (JCMM) Department of Meteorology, University of Reading PO Box 243 Earley Gate Reading Berkshire RG6 6BB UK (saclough@meto.gov.uk) FASTEX Principal Investigators and Data Providers for the FASTEX Ships Ships Name Address -------- ------------------ -------------------------------------- AEGIR Alain Joly Meteo-France/CNRM 42 Av.G.Coriolis 31057 Toulouse Cedex France (alain.joly@meteo.fr) V.BUGAEV Pierre Bessemoulin Meteo-France/CNRM 42 Av.G.Coriolis 31057 Toulouse Cedex France (pierre.bessemoulin@meteo.fr) KNORR Ola Persson NOAA/ETL CIRES, Univ. of Colorado Campus Box 216 Boulder, CO 80309 USA (pogp@etl.noaa.gov) SUROIT Alain Joly Meteo-France/CNRM 42 Av.G.Coriolis 31057 Toulouse Cedex France (alain.joly@meteo.fr) The FASTEX enhanced radiosounding program was supported by AES (Canada), CNRS/INSU (France), DMI (Denmark), the Icelandic Met. Office, Meteo-France, Met Eireann (Ireland), NCAR/MMM (USA), the UK Met. Office, WMO/COSNA. The FASTEX ships were supported by CNRS/INSU (France), The European Commission, IFREMER (France), Meteo-France, NOAA (USA), NSF (USA). 7.0 Composite Sounding Platforms The sites included within the high resolution sounding composite include: Site Country or Platform ---------------------------------------- Aberporth United Kingdom Aegir FASTEX Ship Angmagssalik Greenland Bermuda Bermuda Bordeaux France Boulmer United Kingdom Brest France Victor Bugaev FASTEX Ship Camborne United Kingdom Charleston United States Chatham United States Douce France ASAP Ship Egedessminde Greenland Fort Desaix ASAP Ship Fort Fleur D' Eppe ASAP Ship Fort Royal ASAP Ship Funchal Portugal Godafoss ASAP Ship Goose Bay Canada Gulfstream G-IV Dropsondes Hemsby United Kingdom Hillsborough United Kingdom Irena Arctica ASAP Ship Keflavic Iceland Knorr FASTEX Ship Kuujjuaq Canada La Coruna Spain Lajes Portugal Lear Lear Dropsondes Lerwick United Kingdom Lisbon Portugal Narssarssuaq Greenland NOAA P-3 NOAA P-3 Dropsondes Nuca Arctica ASAP Ship Sable Island Canada Scoresbysund Greenland St. Johns Canada Stornoway United Kingdom Le Suroit FASTEX Ship Thorshavn Faroe Island Trappes France UK C-130 United Kingdom C-130 Dropsondes US C-130 United States C-130 Dropsondes Valentia Ireland Wallops Island United States ---------------------------