Directions for the Gulf of Mexico Near Real-Time Altimeter Data Viewer

Colorado Center for Astrodynamics Research,
Dept. of Aerospace Engineering Science, University of Colorado, Boulder

Welcome to the CCAR Gulf of Mexico Near Real-Time Altimeter Data Viewer. This page gives you detailed instructions on proper use of the data viewer.

Analysis Date

Valid input: Any date included in form.

Global analysis fields are based on the latest 10 days of TOPEX/POSEIDON data and 17 days of ERS 2 data up to and including analysis date. Earlier analysis fields, if available, may be accessed using the pull-down menu.

Geographical Region of Interest

Valid input: Longitude: 262.0 to 280.0 Latitude: 18.0 to 31.0

This allows you to select a region of the Gulf where you would like to view the sea surface height anomaly data. All values are in degrees, and all longitude values are in East Longitude. Minimum values may never exceed maximum values for longitude or latitude.

Note that smaller regions take less time to plot, and the file sizes are usually smaller!

Range of Data Values

Valid input: -100.0 to 100.0

These parameters allow you to choose the range of data values to be color mapped in your plot (units are in centimeters). Any data outside of the range you choose are clipped to the minimum/maximum values of the color scale. If contouring is selected, contours are plotted on full range of the data independent of the range of data values selected.

Color Palette

Valid input: Color, Grayscale, None

This variable defines the color palette to be used in your plot.

• Color - This uses a continuous rainbow color palette between the minimum and maximum range of data values.
• Grayscale - This uses a grayscale color palette between the minimum and maximum range of data values.
• None - This turns all color mapping off.

Contouring

Valid input: 0 to 100 (0 disables contours)

This variable allows you to define a contour interval and/or tick marks on the color bar (units are in centimeters). If a color scheme other than "None" is chosen, contours will overlay the color graphics map.

Bathymetry

Valid input: 0 to 11000

This option provides the capability of editing data in shallow water from your plot (units are in meters). Only data in ocean regions deeper than the input value will be plotted or contoured.

Degree Label Format

Valid input: Any selected radio button

Here you can choose the output format to be used when annotating map boundaries. Choose between the four formats:

• Longitudes go from 0 to 360, latitudes from -90 to 90 [Default].
• Longitudes go from -180 to 180, latitudes from -90 to 90.
• Longitudes are unsigned 0 to 180, latitudes unsigned 0 to 90.
• Longitudes are unsigned 0 to 180 with letters E or W appended, latitudes are unsigned 0 to 90 with N or S appended.

Output File Orientation

Valid input: Portrait, Landscape

Here you can choose the orientation of the plot on the page. One orientation may provide a larger plot over the other.

Output File Format

Valid input: PostScript, GIF

Choose the type of graphics format you wish to receive.

• PostScript - These files have a much larger file size than the GIF format, but are always higher quality. These plots will be downloaded directly to your local machine, and you will need a PostScript viewer/printer to display/print them. Please be patient for these files to transfer, large regions could result in a 1 MB file!
• GIF - This compressed format has a very small file size - generally less than 40K. Some loss of image quality (relative to PostScript) is inevitable. A temporary link to the GIF file is generated, and you may view the file by clicking on the link.

  If you wish to download the plot, please do so promptly! The plot will be removed from our file system after 10 minutes, to conserve disk space!

Back to the Input File...

Page created and maintained by Bob Leben.