CEOP/EOP-1 BALTEX Cabauw IR Radiometer Data CONTACT: Name: Dr Fred Bosveld Affiliation: Royal Netherlands Meteorological Institute Address: P.O. Box 201 3730 AE De Bilt The Netherlands Email: bosveld@knmi.nl Telephone: +31 30 2206 787 (direct) +31 30 2206 911 (general) Fax: +31 30 2210 407 DATA SET INFORMATION: File Naming Structure: cabauw_2001080106_IRADKNMI.txt.gz cabauw = the site 2001080106 = yyyymmddhh (0600 01 August 2001) IRADKNMI = data type KNMI IR Radiometer Instrument Specifications: KT15 Infrared radiometer 1. Contact: Dr. Hannelore Bloemink Royal Netherlands Meteorological Institute (KNMI) P.O. Box 201 3730 AE De Bilt The Netherlands Tel.: +31 (0) 30-2206782 Fax: +31 (0) 30-2210407 email: bloemink@knmi.nl 2. Specifications Receiver type: IR radiation pyrometer, lens system K6 Manufacturer: Heimann Optoelectronics Spectral response: 9.6 to 11.5 micrometer Observation angle: 0-90 deg Opening angle: 50 mrad Temperature range: -50 to + 50 deg C Integration time: 1 s Temperature resolution: 0.5 deg C Interface: RS 232 Dimensions: 161 x 52 x 52 Weight: 0.45 kg 3. Products: Raw data (Level 0): column no. meaning --------------------------------------------------------------------------- 1 date 2 time (UTC) 3 sky temperature (deg C) (1 minute average, 50 measurements) 4 housing temperature (deg C) 5 precipitation indicator (1 = precip., 0 = no precip.) 6 minimum temperature in 1 minute interval (deg C) 7 maximum temperature in 1 minute interval (deg C) 8 number of measurements within 5 deg C of maximum temp. 9 number of measurements within 5 deg C of minimum temp. Format Description: Data for Cabauw, 12/08/2001 - Data in CLIWA-NET format: 35GHz_radar, IR_radiometer, ceilometer, radiosoundings_debilt, windprofiler(?). More details and examples can be found on http://www.meteo.uni-bonn.de/projekte/4d-clouds/dataformat/. CLIWA-NET File format standard A data file consists of three parts: a header, an optional line with y-axis or variables and a data segment. The header gives basic information on variables and some comments. A line with a y-axis or variables is included to make processing in some software packages easier. After the header there is the data section. The measurements are stored one row per time step. Columns contain time (in decimal of an hour), variable 1, variable 2, ... At the moment there are two file formats in use: Format 2.3 and 3.0. Format 2.3 was made for 1 or 2 dimensional data. As for 4d-clouds, more dimensions were neccessary, so a new format was made: 3.0. If possible use the newest format, 3.0. Data providers, please adhere to the standard as close as possible, so that other people do not have to rewrite their reading routines when using your data. There is a lot of redundancy in the format, this can make the files bigger, but it helps to find errors and can make using the data easier for new users. File format 2.3 - The number header lines including this line - Header format version: 2.3 - Data version - Instrument name - Latitude and longitude of the instrument - Elevation of the instrument above the ground - Starting date and time of the data - Ending date and time of the data - Info about the time axis of the data - Info about the other axis, or for 2D data: 0,0,'null','null' - The number of variables used in the data - x lines with the description of the variables: 'name', 'unit', number of columns - Line marking the beginning of the comment lines - x lines with comments - Line marking the end of the header - Optional y-axis or variables - Many line with data File format 3.0 - The number header lines including this line - Header format version: 3.0 - Data version - Instrument name - Latitude and longitude of the instrument - Elevation of the instrument above the ground - Starting date and time of the data - Ending date and time of the data - Number of dimensions - Number of datalines - D lines with information about the axis of the D dimensions - The number of variables used in the data - x lines with the description of the variables: 'name', 'unit', number of columns - Line marking the beginning of the comment lines - x lines with comments - Line marking the end of the header - Optional y-axis or variables - Many line with data Explanations '# HD LINES',x The number header lines: The total number of lines of the header (x=integer), including this line itself, but excluding the line with the y-axis or variables. 'FORMAT VERS',x.x Header format version: This is the version number of the file format, x.x is either 2.3 or 3.0. 'DATA VERS',x.x Data version: This data version number is there to identify updates of the data. The first version will be: 'x.x = 1.0'; smaller updates of the data (new calibrations, small errors corrected, or time synchronized) update the last number: 1.1, 1.2. Bigger changes (new processing methods) update the first number 2.0, 3.0. 'INS NAME','name' Instrument name: this name can also be the tool(s) or the algorithm used, in case of higher level products. 'LAT/LON',f1,f2 Latitude (f1=float) and longitude (f2) of the instrument, if not relevant or if changing (aircraft): 0, 0. 'ELEV',f,'unit' Elevation of the instrument above the ground of f units, if it is changing like for the aircraft: -9999 m. Please, give the height corresponding to the ground as height axis of the products or (and) specify this relation in the comments. 'START',YYYY:MM:DD,HH:MM:SS Starting date and time of the data, year (YYYY) in four numbers, month (MM), day (DD), hour (HH), minutes (MM) and seconds (SS) in two. 'STOP',YYYY:MM:DD,HH:MM:SS Ending date and time of the data, year (YYYY) in four numbers, month (MM), day (DD), hour (HH), minutes (MM) and seconds (SS) in two. 'DIM',x Dimension of the data product, which also specifies the number of '* INFO' lines in the header. This is only used in Format version 3.0. 'DATA LINES',x The number of lines (x) with data. This is only used in Format version 3.0. 'U INFO',f1,f2,f3,'name','unit',dt These lines provide the axis information. The number of these lines is equal to the dimension given in DIM, and they are called U, V, W, X, Y, Z, A, B, ... INFO, respectively. f1, is the number of data bins, f2 the value of the starting bin, f3 the value of the last bin. If the bins are not equidistant, please, specify this in the comments. The first dimension should be time. Only this dimension has to sspecifya time shift (dt), which is the difference between the time the instrument indicated originally and the time used in this data synchronized with other instruments. The last dimension specifies the data bins of the y-axis. If no line with y-axis or variables is given after the header, then x,y,z,'name','unit' should be: 0.0,0.0,0.0,'null','null'. If there is a line with variables present the last dimension INFO should be 1.0,0.0,0.0,'null','null'. 'X INFO',x,y,z,'name','unit',dt 'Y INFO',x,y,z,'name','unit' See 'U INFO for comments. these names are used in format version 2.2.' '# VAR TYPES',x The number of variables (x), which is also the number of headerlines the follows with variable information. Note, that this does not have to be the same as the number of column, as the number of columns with one variable can be more than one. variables 'variable','unit',x Name of the variable ('variable'), its unit ('unit') and how many columns have this value (x), this could for example be drop counts for each diameter bin of an FSSP or radiances at a number of frequencies. If x is bigger than one, please make sure that the user knows exactly what they are, either in the y-axis information (which can only be done for one variable) or in the comments lines. %% BEGIN COMMENT %% END COMMENT Between these two lines you can dump everything, you still wanted to say. It is a good idea to give e-mail and web-adresses for more information and cooperation. y-axis or variables This line is optional, aalthoughits presence should correspond with the right information in the last dimension specified in the header, see 'U INFO'. This line can be used if there is one dimension that is not sampled equidistant. It also makes pplotting2D data easier in packages like Transform and 1D data in sspreadsheetsand many graph-packages. This line is not part of the header. Data lines The data lines should start with a time, then other data sseparated by tabs. Please do not include any non-numeric data in here, but specify values for NaN, +INF, -INF, etc. in the comments. - Data in "Tower" format: meteo, radiation, tower, surface fluxes are all from the Cabauw tower location. The description of the format can be found in the .ctr and .tks files in the relevant subdirectories.