Marwin Shendo
CE 547 GIS
Feb 19th, 2007
Assignment 4
Digital Elevation Models of
Procedure: In order to project my final product I had to take a couple
of steps to get my map. The Digital Elevation Models (DEMs)
of
Further down the assignment
procedure, the Spatial Analyst was introduced. It was a useful tool in creating
the mosaic in the raster calculator. In order to display the final layout
showing my streams, watersheds, and area of analysis, the following commands
were used in raster calculator:
1) Flow direction – creates a grid calculation of flow direction from each
cell to its steepest down sloping neighbor.
2) Flow accumulation – creates a grid of accumulated flow to each cell, by
accumulating the weight for all cells that flow into each down slope cell.
*The following
functions created in the Raster Calculations were restricted to the Rio Puerco Basin.*
3) Stream Grid – establishes an accumulated flow grid that is greater than
278, then its value is changed to 1.
4) Stream link – Assigns unique values to sections of the raster linear network
between intersections.
5) Zonalmax Functions – used to record the maximum value of all cells in the
stream links.
6) Outlets – were determined by comparing the zonalmax
calculation to the flow accumulation.
7) Watersheds – determines the basin boundary above all the cells in zonalmax.
Displaying the different maps was
troubling at first but I pulled each map separately and pasted them in the
paint program. I edited the maps and pasted what I liked on the webpage. I
played around in the layout view to paste the legend of the elevations on the
webpage.
Mosaic of three DEMs
for the Greater Albuquerque area
Mosaic of three DEMs
for the Greater Albuquerque area with
Map of streams and watersheds of the Rio
Puerco Watershed created by Raster Calculation in ArcMap.
All calculation performed in the Spatial Analyst Extension. Streams are
indicated by the blue lines and watersheds are indicated by varies colors.
