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Specifies the upper limit of the cross section, as a pressure level (hPa) or model level (η levels).

Line

Specifies the coordinates of a transect line along which the cross - section is calculated. Enter coordinates (lat/long) of a line separated by a "/" (easternmost lat and long, westernmost lat and long). Alternatively, use the coordinate assist button.

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 generated. Parameter Horizontal Point Mode selects the algorithm used to compute these points.

Note that it is possible to define a line through either pole by describing the line’s coordinates as follows. First, when specifying the latitudes of the two points, imagine that the latitude values go above 90 when you cross the North Pole and below -90 when you cross the South Pole. Next, if you wish a straight line, ensure that the two longitude values are the same as each other. 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.

Wind Parallel

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.

Wind Perpendicular

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.

Wind Intensity

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.

Lnsp Param

Specifies the parameter number of the Lnsp data, if you are using non-ECMWF data - ECMWF uses specific parameter numbers different from the WMO ones. Enter whichever parameter number is appropriate for your data.

U Wind Param

Specifies the parameter number of the U wind component data, if you are using non-ECMWF data - ECMWF uses specific parameter numbers different from the WMO ones. Enter whichever parameter number is appropriate for your data.

V Wind Param

Specifies the parameter number of the V wind component data, if you are using non-ECMWF data - ECMWF uses specific parameter numbers different from the WMO ones. Enter whichever parameter number is appropriate for your data.

W Wind Param

Specifies the parameter number of the W wind component data, if you are using non-ECMWF data - ECMWF uses specific parameter numbers different from the WMO ones. Enter whichever parameter number is appropriate for your data.

Horizontal Point Mode

Specifies how the geographical points along the input transect line will be computed. These points will be used to calculate the cross-section. Valid values are Interpolate and Nearest Gridpoint. Setting this option to Interpolate will create a regular (taking into consideration the resolution of the data and assuring that a minimum of 64 points will be generated) set of interpolated geographical points along the transect line. Setting this option to Nearest Gridpoint will filter the previous set of points by selecting only the instead select the nearest points to from the original grid pointsdata.

Vertical Coordinates

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 model level) where the values of the grid points represent the heights of their locations. Valid values are Default andUser.

Vertical Coordinate Param

Specifies the parameter number of the general height-based coordinates if Vertical Coordinates is set to User.

Vertical Scaling

Specifies the type of vertical axis - Linear or Logarithmic.

Horizontal Axis

Specifies the plotting attributes of the horizontal axis. An Axis Plotting icon can be dropped here.

Vertical Axis

Specifies the plotting attributes of the vertical axis. An Axis Plotting icon can be dropped here.