3 Credit Hours
Concepts and methods of spatial analysis and their application using geographic information systems software and techniques. Emphasizes both theoretical and applied aspects of GIS.
Contact Hour Distribution: 2 hours lecture and 2 hours lab.
I recently ran a model of Hemlock on my personal computer.
I modeled ~489 records; the Nautilus model used over 2,000.
From the model output:
This is a representation of the Maxent model for Tsuga_canadensis. Warmer colors show areas with better predicted conditions. White dots show the presence locations used for training, while violet dots show test locations.
This is not really a fair comparison, but the difference between the models with 489 records and 2000+ is interesting for comparing the predictions.
EECS model for Eastern hemlock is different. It uses more data, and it was run 20 times with 10% of the records reserved before being synthesized into one image.
I will post some additional comparisons for other trees in some later posts.
Geography 414 homework assignment from the Raster database lecture.
Better Raster Clipping Options in ArcGIS
Raster Dataset Homework:
- Get the census tract layer for Hamilton County, TN for TIGER 2010
- Download the NLCD data from the assignments section of Blackboard
- Create a raster layer of land cover for those areas that fall within Hamilton County EXCEPT for tracts
- Create ppt of screen shot and post on bb
My approach to this is to create a new shapefile that does not contain the census tracts to exclude.
SELECT * FROM tl_2-1-_47065_tract10 WHERE "TRACTCE10" = ‘000600’ OR "TRACTCE10" = ‘000800’ OR "TRACTCE10" = ‘003100’
I’m not sure why 10 and 15 were listed as tracts and will need to ask Dr. Ralston about that in class – perhaps I am looking at the wrong attributes.
In some metadata I found at http://datafinder.org/metadata/Census2010Tiger.html <TRACTCE10>, "TRACTCE10" is listed as "2010 Census census tract code"
Also, "NAME10" is defined as "2010 Census Tract Name" – this is the census tract code converted to an integer or integer plus two-digit decimal. Still, however, 10 and 15 were not listed as tracts when sorting by ascending in "NAME10" column in the preview in ArcCatalog.
I chose "Switch Selection" and then "Create Layer from Selected Features" to obtain a new layer, minus tracts 6, 8, and 31.
I then used Raster processing – Clip following the guide at <http://blogs.esri.com/esri/arcgis/2009/05/14/better-raster-clipping-options-in-arcgis-part-b/>.
I used <hamilton_nlcd> clipped previously as the input raster. The output raster is <tl_2010_47065_tract10 selection>.
As a final insult – ArcMap froze up on me – so my final product is faded out, but I took a screen capture with Print Screen.