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Visual Catalog | |
Caribbean/Gulf of Mexico Regional Node |
The following options may be used to control the content of the main plot image:
- Variable:
- Selects the scientific data shown in the plot. Each satellite data file contains a number of variables, shown in the variable selection list. FALSE COLOR is a special selection that creates a false color composite image from several satellite data channels.
- Palette:
- Selects the color palette used to map scientific data values to colors as shown in the color bar legend on the right of the plot. The palette is ignored for false color plots.
- Range:
- Specifies the minimum and maximum scientific data values to map to the first and last colors in the color palette. If no values are specified, the data mean and standard deviation are used to obtain reasonable range values. The range values are ignored for false color plots.
- Zoom subregion:
- Selects the subregion to display in the plot. The full data region is initially shown at a lower resolution than is stored in the satellite data file. Selecting a subregion of interest causes the plot to display a smaller physical area at a higher resolution. Selecting CUSTOM causes the plot to use the values entered in the Zoom (lat/lon/factor) text fields.
- Zoom (lat/lon/factor):
- Specifies the zoom center and factor. The center is specified as a latitude in the range [-90..90] and longitude in the range [-180..180], and the factor as a value generally in the range [1..5]. These text fields are used in conjunction with a CUSTOM zoom subregion (see above). When specified, the custom zoom parameters determine the Earth location of the center of the plot, and the ratio of screen pixels to data pixels. If no custom zoom parameters are specified, the entire data region is shown. When the selected zoom subregion is not CUSTOM, the zoom parameters used for the selected subregion are filled in for reference.
- Grid lines:
- Specifies that latitude and longitude grid lines and labels be overlaid on the plot data for reference. The spacing between grid lines is determined automatically from the total physical area displayed. The minimum grid line spacing is 1 degree.
- Coast lines:
- Specifies that land/water boundary lines be overlaid on the plot data for reference. The accuracy of the coastline data and the display of such features as lakes and islands are dependent on the zoom factor.
- Land mask:
- Specifies that land polygons be filled with a solid color. In some cases such as sea surface temperature plots, land is of no interest and is generally masked off to emphasize that the plot displays oceanographic data only.
- Cloud mask:
- Specifies that clouds over water be filled with a solid color. Similar to land masking, the cloud mask is used to emphasize areas of valid oceanographic data, since clouds interfere with the remotely sensed signal.
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