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Specifies the data (GRIB icon) from which to derive the cross-section profile. The input GRIB icon must specify a multi-level meteorological variable, in a latitude-longitude or Gaussian grid. The following vertical coordinates are supported:
If wind arrows are to be plotted, then the input data should include three-dimensional wind data, i.e. the u/v/w wind components should all be present.
If more than one time and/or forecast step is contained in the GRIB icon, it returns a set of cross sections.
Specifies the coordinates of a transect line along which the cross-section is calculated in lat1/lon1/lat2/lon2
format.
The cross section is calculated from a set of geographical points taken along the input transect line. The point selection takes into consideration the resolution of the data and assures that a minimum of 64 points will be used.
Note that it is possible to define a line through either pole by describing the line’s coordinates as follows:
An example demonstrates this. Say you wanted to defined a straight-line cross-section from 60S/25E to 60S/155W. This would be specified as -60/25/-120/25. The fact that one of the latitude values is below -90 indicates to Metview that a cross-section going through the South Pole is desired. Once this has been established, the fact that the two longitude values are identical tells Metview to use a straight line through the pole. If this is the intent, then only one unique longitude value is required, as the other one can be deduced. Giving Metview two different longitude values will cause a cross-section consisting of two curves to be produced.
Setting this option to On will produce a cross section plot of the projection of the wind onto the cross section plane (going from a 3D wind field to a 2D wind field projection). This is plotted using wind arrows. Valid values are On/Off.
Setting this option to On will produce a cross section plot showing the projection of the horizontal wind components onto the direction perpendicular to the cross section plane. The result is a one-dimensional quantity and is plotted with contour lines. Also produced is another cross section plot of the W component of the wind. Valid values are On/Off.
Setting this option to On will produce a cross section plot of the scalar wind intensity, plotted with contour lines. If one of the previous two parameters is On, then the intensity is that of the specified projection. Also produced is another cross section plot of the W component of the wind. Valid values are On/Off.
Specifies the ecCodes paramId of the LNSP data. The default value is 152 (as used by ECMWF).
Specifies the ecCodes paramId of the U wind component data. The default value is 131 (as used by ECMWF).
Specifies the ecCodes paramId of the V wind component data. The default value is 132 (as used by ECMWF).
Specifies the ecCodes paramId of the vertical wind component data. The default value is 135 i.e. pressure velocity (as used by ECMWF).
Specifies how the geographical points along the input transect line will be computed. Valid values are Interpolate and Nearest Gridpoint. Setting this option to Interpolate will create a regular set of interpolated geographical points along the transect line. Setting this option to Nearest Gridpoint will instead select the nearest points from the data.
Setting this option to User will enable the use of general height-based coordinates. In this mode, additional GRIB fields should be supplied (one per level) where the values of the grid points represent the heights of their locations. Valid values are Default and User.The default value is Default.
Specifies the ecCodes paramId of the general height-based coordinates if Vertical Coordinates is set to User.
Specifies the algorithm to compute the scaling factor for the vertical wind component. Valid values are Automatic and User. Setting this option to Automatic will compute a scaling factor taking into consideration the geographical area, the top/bottom pressure levels and the size of the plot window. Setting this option to User will apply a scaling factor defined by parameter W Wind Scaling Factor.
Specifies the vertical wind scaling factor if W Wind Scaling Factor Mode is set to User.
Specifies the method to define the output pressure levels when converting model level data to pressure levels. Options are:
Specifies a list of output pressure levels separated by a “/”. Only available if Level Selection Type is set to Level List.
Specifies the number of output pressure levels if Level Selection Type is set to Count.
Specifies the type of vertical axis - Linear or Log. Only available if Level Selection Type is set to Count.
Specifies the lower limit of the cross section, i.e. the bottom pressure level (hPa). Only available if Level Selection Type is set to Count.
Specifies the upper limit of the cross section, i.e. the top pressure level (hPa). Only available if Level Selection Type is set to Count.