Introduction
A fundamental concept in Metview is the View. A View specifies the following definitions in a Metview plot:
- type of visualisation (e.g. geographical map, cross section, vertical profile, tephigram)
- parameters specific to that plot type (e.g. geographical area, cross section line, min/max axes values)
- plot position within the page (several plots can share a page)
- how to overlay different data in the same plot (e.g. icon drop rules, data overlay control)
- plot decoration (e.g. draw a frame around the plot)
Without a View specification, Metview would not plot anything. If you do not provide a View, then Metview will use a sensible default View.
For instance, you have previously visualised a GRIB icon by just clicking the icon and selecting option visualise. A Display Window was automatically generated showing a default Geographical View containing a global map in a Cylindrical projection.
(add a picture with 4 views and highlighting the above definitions)
Eight Views specifications are currently available:
| Name | Usage (Used for plotting or Plotting specification for) |
|---|---|
| Geographical View | geographic-based data plots (default View) (link) |
| Cartesian View | plots that are not to be displayed on a map (link) |
| Cross Section View | cross section plots |
| Vertical Profile View | vertical profile plots |
| Average View | average (zonal or meridional) cross-section plots |
| Annotation View | text boxes (link) |
| Hovmøller View | Hovmøller diagram plots |
| Thermo View | thermodynamic diagram plots |
The Geographical View 
This is the default View for plotting geographic-based data. This View was discussed previously in A Quick Tour of Metview.
The Cartesian View 
This will be covered in another session: Graph Plotting in Metview.
The Cross Section View
This icon is a plotting specification for cross section plots from a suitable GRIB data source
Now create a new Cross Section View icon. Visualise it and drop the t_an filter icon into the Display Window. A default cross section is generated. This is an alternative way to view your data - instead of a geographical plot for instance.
Edit the Cross Section View icon and change the transect line - click on the Geography Tool button to bring up an editor (or type the coordinate by hand). Save your changes in the Cross Section View icon and use it to re-visualise the data with this new cross section.
Note that you can still drag any valid contour icons you may have into the Display Window when visualising a cross section.
The Vertical Profile View
Now create a new Vertical Profile View icon. Visualise it and drop the t_an filter icon into the Display Window. This view shows a vertical profile at a point (or averaged over an area). Experiment with this icon in a similar way to how you did with the Cross Section View icon.
The Average View
The Annotation View
The Hovmøller View
The Thermo View
Data Module
Macro
Annotation View
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