Internet Map Server (ArcIMS) is a program for displaying and querying
maps over the Internet. The maps are interactive - a user can zoom in
and out of maps, with different amounts of detail being presented at
different spatial scales. IMS allows different kinds of map layers (roads,
land use, water bodies) to be turned on or off, so customized maps may
be created. A user can also perform interactive queries to collect information
about different items on the map. It is thus a fairly powerful way to
distribute GIS data over the Internet.
primer covers the basics of using IMS - how to get and retrieve information.
In the few minutes it takes to read this, you'll learn all you need
to know to complete the map-based curriculum exercises in Water on the
to the IMS
the curriculum exercises that use IMS have links to a particular lake
or watershed used in that lesson plan. Clicking on the link causes a
lot of things to happen - it wakes up a copy of ARCVIEW residing on
the WOW server, loads all the appropriate data, and delivers the data
over the Internet to the web browser on your computer. As a result,
this link is slower that most web links, although in most cases the
maps are delivered in under a minute. Remember, in the old days, we
had to wait for monks to draw out these maps, and they took a really
long time, so be patient!
figure shows the IMS display for the Medicine Lake watershed. The screen
has four primary sections:
- The Toolbar
for performs various map operations. You can hover over the Toolbar
elements in the figure below to obtain a description of their functions
- this feature works in the actual IMS session as well.
toolbar at the top of the display contains a number of icons that allow
you to manipulate the map. Their functions are described below:
legend and layer list (newer versions show both without toggling)
- allows you to view the overview map
Zoom In - allows you to obtain a close-up view of an area of the
map. A key feature of the zoom tool in IMS is that it can be programmed
show progressively more information as you zoom in.
Zoom Out - very similar to Zoom In, but the other way
Zooms out to the furthest extent of the map
the active layer in the view window
Back to last
- fancy way of saying go back to last view
- allows you to move the map back and forth, up and down. This is useful
if you have zoomed in to the map and want to see something that is
- allow you to mone the map to the North, South, East or West.
This is useful if you have zoomed in to the map and want to see something
that is off the screen.
- allows you to link to data. Links can also be accessed via the Identify tool.
Identify - An important tool, it allows you to retrieve information
about a particular map object
Query - Ask
questions within or across map layers. Click
here for a tutorial on the
- allows you to search the active layer
- allows you to measure the distance between 2 points. Keeps a cumalative tally
of measurements until cleared
with the Clear selection button.
- sets the units for the measurement tool
- allows you to created a visual buffer of a set size around a selected feature.
- used to select a feature in the active layer
- used to select a line or polygon in the active layer
- zeros the measurement tool
Print - sends the map to your local printer
- The Layers
window on the right presents an interactive legend that allows different
map elements to be viewed and queried. The Visible checkbox determines
which layers are displayed. The Active radio button determines
which layer returns information when the Identify Tool is
used. Use the Refresh Map button will redraw the screen to
update changes in the Layers window. The Toggle Tool in the
upper left corner of the toolbar will toggle between this Layers
window and a Legend window,
which provides a color and symbol legend for each of the map elements.
- The central
map viewing frame diplays the visible layers. This map can be manipulated
(zoom, pan, query) using the Toolbar tools.
- The information
window below the map returns results from map queries.
things to know:
composed of lines, such as roads and streams, overlay quite easily.
Layers which are based on polygons that cover the map, such as land
use or soil types, however, can only be viewed one at a time. For this
reason, a map layer may be 'hidden', i.e. the layer might be turned
on, but you won't be able to see it. By convention, IMS draws layers
at the bottom of the legend first. In the figure above, the Land Use
map is drawn first, followed by the Parks layer, followed by Game Refuges,
etc. If a layer seems hidden, turn off the layers above it to make it
the tasks you will perform in IMS involve setting up a view of the map
that shows what you want to see, and using the Identify or query tools
to retrieve information on map objects. The Identify tool returns information
in a data table that opens either in a new browser window, or within
the current map window. You can also measure distance, construct sophisticated
queries on tables, or select and analyze multiple features. The best
way to learn what these tools do is to try them!
from the data display windows can be copied and pasted into a WOW exercise
data table using standard Windows/Mac copy and paste conventions.
IMS stores information with a lot more precision than you really need
(or is justifiable, given the inherent error in the mapping process).
For example, the Identify tool reports the area of one of the Farmsteads
as 27711.57356 square meters. Feel free to round this to 27712 square
meters. Heck, 2.8 hectares would be OK. (10,000 m2/ha).
information on using IMS can be found at the ESRI