Geostatistics for the Environmental Sciences

Mapping

GS+ can produce 3D, 2D, and 1D maps of spatial data following interpolation. The data to be mapped are contained in output files created during interpolation. Maps can be displayed with different contouring schemes, 3-dimensional maps can be rotated on the fly, and both 2-dimensional and 3-dimensional maps can be zoomed to more closely view a transition or other map feature. Additionally, sample postings (original data locations) can be displayed, and estimation standard errors can be mapped for input files that have been saved in the standard GS+ format.

Map design window
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GS+ 2D Surface Map
GS+ produces 2D surface maps in addition to 3D maps. The lower right Mouse Location panel reports the location of the mouse when it is moved over the image. Zooming is performed by setting a Mouse Action and outlining part the image with the mouse. The Edit Graph button allows the projection to be changed to 3D, axes to be rescaled, labels and backgrounds to be changed, and titles added.


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GS+ 3D Map Image Window
GS+ produces 3D contour models as well as 2D surface maps for data kriged in 2 dimensions. From this Map Image window the map can be edited, printed, and rotated and zoomed on the fly. A Mouse Location Panel (lower right) reports the location of the mouse when it is moved over the image. The Edit Graph button allows axes to be rescaled, labels to be changed, background colors to be defined, and titles added. Maps can be printed to any Windows device, to the clipboard, or to a file in a variety of formats including web-ready formats like JPEG. The Map Definition window defines how the map is drawn.


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GS+ Estimation Error Map
In addition to maps of a particular variate, you can also map the estimation error associated with the variate. These maps are available from files saved in GS+ format (ArcView® and Surfer® formats don't support estimation error). The type of map drawn is specified in the Map Design Window.

The lower right Mouse Location panel reports the location of the mouse when it is moved over the image. Rotating and zooming is performed by setting a Mouse Action and grabbing the image with the mouse. The Edit Graph button allows the projection to be changed to 2D, axes to be rescaled, backgrounds and labels to be changed, and titles added, as for all other graphs in GS+.


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GS+ 2D Map Postings
Graph the locations of sample points on top of your maps – each symbol in the image marks an actual sample location in the original data set. A posting is also available for 3D and 1D maps, as is a plain 2D posting without the underlying contour map. As for other maps, the lower right Mouse Location panel reports the location of the mouse when it is moved over the image. Zooming is performed by setting a Mouse Action and grabbing the image with the mouse. The Edit Graph button allows axes to be rescaled, labels to be changed, and titles added.

Quintile maps (scattergrams) provide a posting of data values prior to interpolation.


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Defining Map Contour Intervals in GS+
GS+ gives you complete control over map contour intervals. In the Map Contour Intervals dialog you may change the default break points and colors for map contours. The number of contour intervals (1 - 15) is specified in the Map window. Customized intervals (both break points and color schemes) can be saved to allow different maps to easily share the same contouring schemes. Clicking on a color tab brings up a color dialog window with the full suite of colors that Windows supports. Missing values, including areas within "exclusive" polygons, are mapped as blank spots (background color).


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GS+ Map Color Schemes
Maps can be given any number of color schemes. Choose among predefined schemes such as this blue scheme or customize contour intervals as you like from the Contour Definition window. Background colors can also be changed.

Show blue color scheme
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GS+ 3D Map Rotation
3D maps can be rotated to any perspective, as noted here for a bottom view of a rotated map of estimation error. Rotations are performed from the Map Image Window.


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GS+ 1D Transects
In addition to 2-dimensional spatial data, 1-dimensional data such as linear transects or sampling through time can also be interpolated, and the resulting data graphed as a 1D transect or time-line image. The symbols in this graph represent actual sample values of temperature vs. day of year and the black line represents a dense grid of block-kriged values interpolated at 0.1 day intervals.

The lower right Mouse Location panel reports the location of the mouse when it is moved over the transect. Zooming is performed by setting a Mouse Action and outlining a portion of the image with the mouse. The Edit Graph button allows axes to be rescaled, labels and backgrounds to be changed, and titles added.


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GS+ 1D Estimation Error
Kriging produces an estimation error term for every value interpolated, and you can graph this error to provide insight on portions of the model for which you may have more confidence than other portions. The blue lines here represent the standard deviations (estimation error) of the kriged values, which are reported as the black line.


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3D Map Options include

 
 

GS+ 3D Map with Black Background, Pedestal
Maps can be drawn with backgrounds of any color provided by Windows, and 3D maps can be drawn with or without base pedestals. This image was printed from the Map Image window to a JPEG file. Pedestals are specified in the Map Design Window.

GS+3d map
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GS+ 3D Map with Floor Contours
Maps can be drawn with contours projected onto the ceiling or floor of the image. This image had contours projected below the surface and was printed from the Map Design Window to a JPEG file. Floor contours are specified in the Map Design Window.

GS+3d map
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GS+ 3D Map with Floor Bands
Maps can be drawn with contour lines or bands projected onto the ceiling or floor of the image. This image has bands projected below the surface and was printed from the Map Image window to a JPEG file. Note that the wire frame density on this map surface is set to a very high value. Floor bands are specified in the Map Design Window.

GS+3d map
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Axis Grids on Maps in GS+
Maps can be drawn with grids projected onto any of the axes. Gridding is available for 1D, 2D, and 3D graphs, as for this 3D graph of estimation variance. In this case, a grid was projected along all three axes before the map was printed to a JPEG file. Grids are specified in the Map Design Window.

GS+3d map
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