DATA SOURCES & METHODOLOGY
DATA SOURCES:
•Land use data which came from the Data Warehouse in the GIS Lab:
SIS Data > Data Warehouse > Landuse > GVRD_2001 > gvrd_2001_landuse.shp
•Data elevation model (DEM) which was taken from the Data Warehouse in the GIS Lab:
SIS Data > Data Warehouse > DEMs > GVRD_20m_DEM
DATA MANIPULATION:
First, I created an Excel spread sheet with the land use types in the attribute table with the same ID numbers to match the shapefile ID numbers in order to join the two data sets together to determine the land use zones. This was accomplished in ArcMap 10.1. After joining the two tables I was able to go into symbology in layer properties and make all the classes display. Next I used a conversion tool called ‘Polygon to Raster’ in the Arc Toolbox to convert my shapefile into rater data. I had to export the raster data so that I could have the entire raster data set with the table as a map layer. I was then able to convert the raster data set to ASCII so that I could export it into IDRISI. In IDRISI, I imported the file by hitting: file > Import > software specific formats > ESRI formats > arcraster. This put the file, called landuse222.rst, into IDRISI format and allowed me to start manipulating it. I had to change the reference system from plane to UTM-10n.
This data set had multiple images that needed to be merged together in Arc with the merge tool so Blake helped me with this conversion to make sure that they were all in the same projection before they were merged so that they would all align and be in UTM-10N. It was then was imported into IDRISI. This raster is called MetroVanDEM_UTM.rst.
Once this file was imported into IDRISI I had to use a reformat tool called ‘window’ to cut out the part of the image I wanted from my DEM to match the size of my landuse raster.
Then, I had to use another reformat tool called ‘resample’ to align the rows and columns and resolution of the two data sets by setting up ground control points based on X and Y coordinates, which looks like this:
After getting my sources imported and resampled to be the same resolution and coordinates, I had to reclass my landuse zones and make sure the colors matched the land classes. I assigned the land classes using the module assign and used layer properties to select a qualitative palette.
METHODOLOGY
My methodology was quite simple. I had to use the module reclass to assign the values of elevations that I wanted my boolean map to include or exclude. I did this three times because I wanted to analyze the data based on a 1 meter, 2 meter and 10 meter increase in sea level to see where the greatest impacts would take place depending on the increase.
I overlayed it with the landuse map and got 3 boolean images which cover areas with water and where the water spills over to the land based on the elevation increase from 0 meters.
