(new user) Problem with Spatial Analyst

[Jaume]

Hello

I am a new user of ArcGIS and I am currently using it in an academic
project. I am supposed to create a n hydrological model from a place
in Dominican Republic. I was given a group of files with the following
extensions: .TIF, . AUX, .RRD, .STK, .TFW, .XML. All of them with the
same file name. When I add data and select the .TIF file, it creates
three layers with the name of the file plus "- Band_1", "-Band_2" and
"Band_3". Each of these show a map with gray scales indicating
elevation or depressions in the terrain.

My questions are these:

Can I do the hydrological model form this data? If so, which tool I
must use?
Why are there three bands? does they have a specific meaning? Which
one should I use to create the hydrological model?

Best Regards

Alberto

[dsl]

When adding the tif file, do not double click on it, just select the
file and add it. This should load it as a complete file instead of in
bands.

To answer your question. If you are planning on doing Hydrological
analysis in ArcGIS with Spatial Analyst. Get the free ArcHydro
extension. You need elevation information and a stream layer for the
most basic functionality.

I'm not sure why your elevation data is tif format. Usually it is a
DEM or TIN or ESRI grid format. You'll have to talk to the source who
gave you the data. I suppose the value of each pixel/cell could be an
elevation value.

David