Home > Great Lakes CoastWatch Java GIS
Great Lakes CoastWatch Java GIS
Select Image Type
Select Shapefiles of interest
Press "Load Data"
- files will appear in "Loaded ShapeFiles" window
Java applet allows the examination of
oceanographic satellite imagery with ancillary data sets (overlays). The applet will
start two new windows (Panner window and Image window) for viewing the near real-time
images and a Control Panel window for toggling on and off the marine observation data and shapefile
- Water Surface Temperature Imagery: The Great Lakes SST imagery used in this JAVA
applet is in TIF format. The imagery is produced from 1024 x 1024 CoastWatch data
files (1.3 km resolution) obtained from NOAA 14 and NOAA 15 AVHRR satellite sensors.
- Histogram Equalized Ch.1 Imagery: The Great Lakes Ch. 1 (visible) reflectance
imagery used in this JAVA applet is in TIF format. The imagery is produced from 1024 x
1024 CoastWatch data files (1.3 km resolution) obtained from NOAA 14 and NOAA 15 AVHRR
- GLSEA Temperature Composite Chart: The Great Lakes Surface Environmental
Analysis (GLSEA) temperature composite chart is produced from CoastWatch near real-time
AVHRR surface temperature imagery. This cloud-free product is available daily for the
- Great Lakes Ice Analysis Chart: During the winter season, the National Ice
Center (NIC) produces a Great Lakes Ice Analysis Chart. The chart shows ice cover
concentration (in tenths) on the Great Lakes and is produced at least once a week. The
Canadian Ice Center produces a similar chart once a week. These charts (in digital
format) are used to produce the ice cover concentration overlay on the GLSEA chart and
are also available as an image type in the JAVA applet.
- Great Lakes Shoreline: derived from the World Vector Shoreline (WVS). It is in the
WGS-84 datum/spheroid, geographic projection.
- Great Lakes Bathymetry: bathymetry is modified from the high resolution
Great Lakes bathymetric data set produced by the NOAA National Geophysical Data Center
(NGDC), Great Lakes Environmental Research Laboratory (GLERL), and the Canadian Hydrographic
There is a list of available shapefiles in the box labeled "Available ShapeFiles". In
addition, you may add your own shapefiles for the areas that interest you by putting them
where a web server can see them and entering the URL in the "Custom Shapefile
URL" box. Also add a Custom Label Name so the resulting checkbox will have a name. Note that
the shapefiles should be placed under the web server
DocumentRoot and must be visible to the world via a web server
(for example, http://yourserver.localDomain.rootDomain/yourfile.shp). Browser security
restrictions prevent the java applet from downloading files that look like local files.
- For creating Great Lakes shapefiles:
Frequently Asked Questions:
- How do I turn on marine observation data or other coverages (shapefiles)?
In the Control Panel window, click on the "Menu" box to display available marine
observation and nowcast wind data. Click on "coverages" to display a list of
loaded shapefiles. Use the "Wind Vector" box to toggle marine observation data on
or off. Use the box next to the shapefile of interest to toggle the overlay on or
- How do I change colors of the ancillary (overlay) data to make it more
visible against the image background?
Among the buttons in the Control Panel window is a choice box with a color name in
it (black to start). Use this choice box to select a color. The colors for the
shapefiles (coverages) are available from a separate dialog box when you turn the
shapefile's checkbox on.
- How do I scroll or pan around the image?
The Image Panner window contains a small version of the selected image. Inside
this window is a black rectangle which starts near the upper left corner. The size
and position of the rectangle reflect the view in the Image window. You can drag
the rectangle to the area of the image you want to see in the Image window.
- How do I change the size of the Panner Image window's rectangle?
The size of the rectangle changes automatically to reflect what is going on in the
Image window. If you enlarge the Image window, the rectangle will get larger. If
you zoom-in on the image in the Image window, the rectangle gets smaller.
- Is there a way to zoom-in and zoom-out using the mouse instead of the
buttons (found under "View" in the Image window)?
Yes. The buttons will zoom in or out while attempting to maintain the center of
the image in the same place. If you use a three button mouse, the second and third
buttons are used to zoom in and out and will maintain the point under the mouse at
the same point on the screen. For a single button mouse, try using the shift and
- How can I save the image on the screen?
The browsers security constraints prevent the applet from writing a file, such as a GIF,
to your local machine. The only way for the applet to make an image file for you would be
to create a GIF or JPEG, send it back to the server and have the server send it to your
browser. Not only is this wasteful of bandwidth, it would open a nasty security problem on
the server. The best way to save the image is to use a screen capture program such
as WinGrab (freeware) or
Snaglt (shareware) .