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:

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. 

Now create a new Cross Section View icon. Visualise it and drop the t_an.grib icon into the Display Window. A default cross section along the Equator is generated. This is an alternative way to view your data - instead of a geographical plot for instance.

Inspect the GRIB icon (right-click on it and choose examine) to see the type of input data this view requires,

Edit the Cross Section View icon and change the transect line (coordinates along which the cross-section is calculated).- 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 Contouring icons you may have into the Display Window when visualising a cross section.

The Vertical Profile View    

This icon is a plotting specification for vertical profile plots.

Create a new Vertical Profile View icon. Visualise it and drop the t_an.grib 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.

Graph Plotting icon????

The Average View    

This icon is a plotting specification for average (zonal or meridional) cross-section plots.

Create a new Average View icon. Visualise it and drop the t_an.grib icon into the Display Window. A default meridional average over the globe cross-section is generated. Experiment with this icon in a similar way to how you did with the Cross Section View icon.

You can use a Contouring icon to style the contours of the plotting.

The Annotation View    

This icon provides a container for user-defined text boxes.

Create a new Annotation View icon and visualise it.  The user text is provided by means of a Text Plotting icon. Create a new instance of this icon and rename it to note1. Edit it, setting the following parameters:

Apply the changes and drag the note1 icon into the Display Window.

Experiment with this icon by changing other parameters, for instance, the font style and size. Also, multiple Text Plotting icons can be placed in this View. Duplicate the note1 icon, rename it, customise it (remember to define an appropriate text box) and drag it into the Display Window.

The Hovmøller View   

This icon is a plotting specification for Hovmøller diagram plots along a specified arbitrary transect line or a rectangular area. The diagram displays a two-dimensional graph with latitude or height as one axis and time as the other.

Create a new Hovmoeller View icon. Visualise it and drop the t_ts.grib icon into the Display Window. A default diagram derived from a transect line along the Equator is generated.

Examine the GRIB icon to see the sort of input data this view requires,

Three types of Hovmøller diagrams can be produced:

1.  Area Hovm     - diagram derived from an input rectangular area
2.  Line Hovm      - diagram derived from an input transect line
3.  Vertical Hovm - diagram derived from an input rectangular area and a set of levels.

Experiment with this icon by testing the above types and investigating other input parameters. Type Vertical Hovm requires the following input GRIB data: t_ts_nlevels.grib. Examine and compare this GRIB data with the previous one.

The Thermo View   

Data Module

Macro

Annotation View

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Layout