Wind input files
At present, for different wind input files, different headers are used, which are read in different ways in the sourcecode. Some effort has been put in making the files more self-descriptive, readible and to make the input of the different files more consistent. For four wind-input options, a suggestion to standardise the headers is shown below. The suggestion is conform a possible transition to NetCDF format in the future. See NetCDF standard names for more information on the used standard NetCDF names. For Space Varying Wind and Pressure, Pseudo ArcInfo wind, wind on a separate curvi-linear grid and Spiderweb wind, examples of input files are shown below.
- Keywords are case INsensitive.
- Comments are indicated by a #.
- The keyword FileVersion (= 1.0) must be the first keyword, the order of the other keywords is free to choose.
--------------------------------------------------------------------------------------------------------------------------
- Space Varying Wind and Pressure:
### START OF HEADER ### This file is created by Deltares FileVersion = 1.0 # Version of meteo input file, to check if the new file format is used (1.0) meteotype = svwp_on_flow_grid # Type of meteo input file: curvi, arcinfo or spiderweb NODATA_value = -9.9900000E+02 # Value used for undefined or missing data n_quantity = 3 # Number of quantities prescribed in the file quantity1 = x_wind # Name of quantity1 quantity2 = y_wind # Name of quantity2 quantity3 = air_pressure # Name of quantity3 unit1 = m s-1 # Unit of quantity1 unit2 = m s-1 # Unit of quantity2 unit3 = mbar # Unit of quantity3 ### END OF HEADER TIME = 0 minutes since 2008-01-08 00:00:00 +00:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> 0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 -9.9900000E+02 -9.9900000E+02 -8.6049000E+00 -1.0240000E+01 -5.4150000E+00 -1.8900000E+00 -2.9040000E+00 -9.9900000E+02 -9.9900000E+02 -9.9900000E+02 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 -1.0000000E+01 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 1.0000000E+03 TIME = 660 minutes since 2008-01-08 00:00:00 +00:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> 0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 -9.9900000E+02 -9.9900000E+02 -2.3290000E+00 -9.0440000E+00 -1.3230000E+01 -8.3310000E+00 -6.9210000E+00 -9.9900000E+02 -9.9900000E+02 -9.9900000E+02 -1.0000000E+01 -1.1000000E+01 -1.2000000E+01 -1.5000000E+01 -1.8000000E+01 -1.4000000E+01 -1.2000000E+01 -0.8000000E+01 -1.2000000E+01 -1.6000000E+01 -1.2000000E+01 -1.0000000E+01 -0.7000000E+01 -0.4000000E+01 0.0000000E+00 -0.3000000E+01 1.0130000E+03 1.0140000E+03 1.0140000E+03 1.0160000E+03 1.0120000E+03 1.0120000E+03 1.0180000E+03 1.0200000E+03 1.0160000E+03 1.0140000E+03 1.0110000E+03 1.0130000E+03 1.0110000E+03 1.0180000E+03 1.0150000E+03 1.0130000E+03
- Pseudo ArcInfo wind:
### START OF HEADER ### This file is created by Deltares ### All text on a line behind the first # is parsed as commentary ### Additional commments FileVersion = 1.0 # Version of meteo input file, to check if the new file format is used (1.0) meteotype = arcinfo # Type of meteo input file: curvi, arcinfo or spiderweb NODATA_value = -9999.000 # Value used for undefined or missing data n_cols = 400 # Number of columns used for wind datafield n_rows = 16 # Number of rows used for wind datafield grid_unit = degree # Unit of distances on the grid in both x- and y-direction: m or degree x_llcorner = -12.000 # Xcoordinate of lower left corner of grid (in units specified in grid_unit) y_llcorner = 48.000 # Ycoordinate of lower left corner of grid (in units specified in grid_unit) value_pos = centre # Coordinates given in centre or corner of lower left cell? dx = 0.12500 # Grid dimensions: dx and dy (in units specified in grid_unit) dy = 0.083333333 n_quantity = 1 # Number of quantities prescribed in the file quantity1 = x_wind # Name of quantity1 (x_wind, y_wind or air_pressure) unit1 = m s-1 # Unit of quantity1 (m s-1 for velocities or Pa/ mbar for air_pressure) ### END OF HEADER TIME = 0 minutes since 2007-10-08 15:24:00 -02:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 2.388999 2.388999 2.388999 2.388999 2.388999 2.388999 2.388999 2.388999 2.388999 2.388999 3.388999 3.388999 3.388999 3.388999 3.388999 3.388999 3.388999 3.388999 3.388999 3.388999 TIME = 1440 minutes since 2007-10-08 15:24:00 -02:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> 2.435253 2.435253 5.435253 1.435253 3.435253 4.435253 2.435253 2.557653 2.412253 2.435255 1.435253 2.435253 1.435253 2.435253 1.435253 2.435253 1.435253 1.435253 2.435253 1.435251 4.435253 4.435253 1.435253 3.355253 3.456253 5.425253 1.223453 5.523341 5.521246 3.255258
- Explanation of the data to grid conversion for Pseudo ArcInfo wind
For Pseudo ArcInfo wind the orientation of the data is the same as the grid (visually). The first data value is thus located at the grid at (1,nmax). A line is then read as a row on the grid and the 2nd line in the dataset is row nmax-1 on the grid. See also figure 1.
Figure 1: Data to grid conversion for Pseudo ArcInfo wind.
- Wind on a separate curvi-linear grid:
### START OF HEADER ### This file is created by Deltares ### All text on a line behind the first # is parsed as commentary ### Additional commments FileVersion = 1.0 # Version of meteo input file, to check if the new file format is used (1.0) meteotype = curvi # Type of meteo input file: curvi, arcinfo or spiderweb NODATA_value = -999.999 # Value used for undefined or missing data curvi_grid_file = hirlam.grd # Separate (curvi-linear) grid on which the wind can be specified first_data_value = grid_llcorner # Options: grid_llcorner, grid_ul_corner, grid_lrcorner or grid_urcorner data_row = grid_row # Options: grid_row or grid_col. For switching rows and columns. n_quantity = 1 # Number of quantities prescribed in the file quantity1 = x_wind # Name of quantity1 (x_wind, y_wind or air_pressure) unit1 = m s-1 # Unit of quantity1 (m s-1 for velocities or Pa/ mbar for air_pressure) ### END OF HEADER TIME = 0 hours since 2006-01-01 00:00:00 -06:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> 101530.000 101300.000 101600.000 101550.000 101500.000 101300.000 1013300.000 101400.000 101430.000 101500.000 101130.000 101320.000 101260.000 101620.000 1013400.000 101520.000 TIME = 1440 hours since 2006-01-01 00:00:00 -06:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> 101298.544 102108.102 101998.521 101928.544 101721.314 101811.152 1013410.400 101323.214 101430.000 101500.000 101130.000 101320.000 101260.000 101620.000 1013400.000 101520.000
- Explanation of the data to grid conversion for wind on a separate curvi-linear grid.
The first_data_value keyword is used to determine the starting point on the grid. The first_data_value is the first value that is read in the meteo file, i.e. the upper left value in a datablock. The keyword has 4 possible values:
grid_llcorner, meaning m = 1, n = 1 (on the curvilinear grid)
grid_lrcorner, meaning m = mmax, n = 1 ( " )
grid_ulcorner, meaning m = 1, n = nmax ( " )
grid_urcorner, meaning m = mmax, n = nmax ( " )
The data_row keyword is then used to determine the direction of placing the data on the grid, i.e. data_row = grid_column means that a row that is read in the meteo file becomes a column in the array on the grid (so fixed m, increasing n).
Example:
first_data_value = grid_ll_corner data_row = grid_column
means:
The first read value (top left) of the meteofile coincides with the point (1,1) on the grid. The first row in the meteofile is then the first column on the grid, i.e. (1,1:nmax). The second row is then the second column (2,1:nmax) and so on. See also Figure 2.
Figure 2: Data to grid conversion for wind on a separate curvi-linear grid.
- Spiderweb wind:
### START OF HEADER ### This file is created by Deltares ### All text on a line behind the first # is parsed as commentary ### Additional commments FileVersion = 1.0 # Version of meteo input file, to check if the new file format is used (1.0) meteotype = spiderweb # Type of meteo input file: curvi, arcinfo or spiderweb NODATA_value = -999.000 # Value used for undefined or missing data n_cols = 400 # Number of columns used for wind datafield n_rows = 16 # Number of rows used for wind datafield spw_radius = 600000.00 # Radius of spiderweb (in units specified in rad_unit) spw_rad_unit = m # Unit of radius n_quantity = 3 # Number of quantities prescribed in the file quantity1 = wind_speed # Name of quantity1 quantity2 = wind_from_direction # Name of quantity2 quantity3 = air_pressure_drop # Name of quantity3 unit1 = m s-1 # Unit of quantity1 unit2 = degree # Unit of quantity2 unit3 = Pa # Unit of quantity3 ### END OF HEADER TIME = 0 minutes since 2004-01-03 11:02:00 +01:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> x_spw_eye = 115.4 # Xcoordinate of cyclone eye (Spiderweb centre) at specified TIME y_spw_eye = 18.9 # Ycoordinate of cyclone eye (Spiderweb centre) at specified TIME p_drop_spw_eye = 5300 # Pressure drop at cyclone eye (Spiderweb centre) at specified TIME 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 1.388999 155.0000 346.2500 357.5000 8.750000 20.00000 31.25000 42.50000 53.75000 65.00000 76.25000 5300.000 5300.000 5300.000 5300.000 5300.000 5300.000 5300.000 5300.000 5300.000 5300.000 TIME = 1440 minutes since 2004-01-03 11:02:00 +01:00 # Fixed format: <time> <time unit> "since" <date> <time> <time zone> x_spw_eye = 114.4000 # Xcoordinate of cyclone eye (Spiderweb centre) at specified TIME y_spw_eye = 18.90000 # Ycoordinate of cyclone eye (Spiderweb centre) at specified TIME p_drop_spw_eye = 5300.000 # Pressure drop at cyclone eye (Spiderweb centre) at specified TIME 2.435253 2.435253 2.435253 2.435253 2.435253 2.435253 2.435253 2.435253 2.435253 2.435253 65.01978 75.11859 85.25320 95.45370 105.7529 116.1833 126.7762 137.5612 148.5649 159.8090 5298.544 5298.544 5298.544 5298.544 5298.544 5298.544 5298.544 5298.544 5298.544 5298.544
--------------------------------------------------------------------------------------------------------------------------