Objective: To calculate the area of a polygon extracted from a Landsat scene, using ARCGIS 10. Credits as well as copyrights are the same of the previous entries (Buitrón and Fernandez, 2012).
1. Create a folder DATA GIS where to store the archives to be created in ARCGIS.
2.
Open ArcMap 10. Go to Catalog and
search the folder DATA GIS. Inside create a new folder and set the name of the
image l519971016, Inside this folder create a Personal Geodatabase, using the
name of the image; inside it create a FeatureDataset with the name GLACIER→ Next and will pop up
a window “New Feature Dataset”. Go to “GeographicCoordinateSystem” and “Import”;
load the image l519971016.shp →Add→ Next, then it will
appear the same window, go to “Vertical CoordinateSystems”→ “World”→ “WGS 1984” →”Next”→ “Finish”
3. Inside the folder GLACIER create several FeatureClass using the name of
the glaciers we wish to delineate.
4. Inside the
folder GLACIER go to “Import” →FeatureClass (single)
and in “Input Features” search for the image in shape format. In “Output
Location” save inside the folder GLACIER; in “Output FeatureClass” write down
the name GLAS and OK
4. On the table of Contents can be seen all folders that have been created
inside GLACIER, but only GLAS has the image l519971016.shp, since the remaining
ones are empty.
5. Go to “Editor”→”StartEditing” and go to “SelectFeaturesbyrectangle”, with this tool select the corresponding directory
of every glacier.
6.
In the toolbar go to “Edit” →Cut, then the
selection will disappear; again in “Edit”→ Paste and select the
locations where the image will be pasted. Do the same procedure with all
glaciers. To finish, go to “Editor”→ “Stop Editing”. At the end, the folder
GLAS will be empty and the folders of the glaciers will store the data of the corresponding
glacier.
7.
If you open the
table of attributes of each folder, you will see that every glacier is composed
by several polygons. Then, to join all that information into a single polygon, in the toolbar
go to “Geoprocesing” →“Dissolve”, in “Input feature” load
the archive of, e.g., the glacier SAJ and in “Output FeatureClass” direct the
file to the address where the archive will be stored e.g., with the name “SAJAMA”
→ OK.
When opening the table of attributes of SAJAMA, you will see that all
the information has been joined. In this table you will find the information on
the area, the perimeter, etc, of the glacier.
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