1. GIT461/561 GIS: Environmental Science
Introductory Lecture
By David T. Allison, Ph.D.

2. Lecture 1 Lecture 1 Topics
Introduction to GIS lab equipment and protocols
Basics of Operating Systems and File Management
Basics of Map Projections and how they work in ArcGIS
Sources of Digital Base Maps
Starting the Yosemite Valley Project

3. GIS Laboratory Usage Rules for Using the GIS Lab (LSCB 137)
The lab is for use only by students taking GIS-based courses within the Dept. of Earth Sciences
Do not use the workstations for tasks other than GIS course work (no checking , music downloading, printing term papers, etc.)
No food or drink is allowed in the lab
Do not give out the lab door combo to friends, family, etc.
Try not to touch the screen with your fingers, instead use the eraser end of a pencil
Don’t leave book bags, purses or other gear in the lab unattended

4. GIS Lab Hardware LSCB 333 - 24 “Thin Client” workstations:
Intel Xeon 2-core CPU 2.4 Ghz
2.0 Gb RAM
40 Gb HD
HP 5500 Color DesignJet Plotter (60 inches x 150 feet).
HP LaserJet 200 color laser printer.
36 inch wide 600 dpi scanner (146 LSCB).
LSCB 146 – 12 workstations.

5. GIS Lab Workstation Software
Each workstation is a virtual client running Windows 7 from a server.
Workstation Application Software:
ArcGIS 10.2
Microsoft Office Professional 2012
Excel
Word
Access
PowerPoint
Google Chrome
Google Drive

6. Client/Server Model Advantages/Disadvantages
Server “serves up” the same OS and Application environment to all workstations.
Cheaper to maintain and purchase.
Upgrading software: one-step process.
Disadvantages
Users (students) cannot store work on hard drive because it is initialized to a standard state on every re-boot.
Performance is limited by server bandwidth.

7. Operating Systems
Software interface between hardware and application software (i.e. ArcGIS).
OS systems: Windows, MacOS, Unix, Linux, Android
Currently ArcGIS desktop software runs on Windows, however, file servers that make ArcGIS maps available on the web are likely to run Linux with Apache server.

8. Windows 7 File Management
Most problems in ArcGIS assignments stem from poor file management skills.
Do’s and Don’ts:
Do learn Win7 file explorer application.
Don’t copy files/folders to the desktop.
Do learn how to copy entire folders from one disk to another in one step.
Don’t save ArcGIS projects to a flash drive from within the application- exit first and use file explorer to copy folder to flash drive.
Do learn how Google Drive/Dropbox work so that your work is stored safely in the “cloud”.

9. Windows 7 Desktop with ArcGIS Installed

10. ArcGIS 10.x Components
ArcMap Application: basic map-making application for ArcGIS.
ArcCatalog Application: file management and file creation application for ArcGIS.
ArcScene: application for manipulating and presenting 3D perspectives of 3D data (ex. “fly-through” videos).
Spatial Analyst extension: manages spatially related data relationships (ex. produces a contour map from topographic survey data).
3D Analyst extension: manages the geometry of three-dimensional data (ex. subtracts a lower contact from an upper contact to produce an isolith map).

11. GIS/Map Terminology
DRG: digital raster graphic. A scanned topo or aerial map that is georeferenced.
DEM: digital elevation model. A rectangular array of elevation values. Usually interpolated from survey data.
GCS: geographic coordinate system. Locations are measured with latitude and longitude.
UTM: a world-wide projected coordinate system using meter units.
SPCS: State Plane coordinate system- a U.S. state specific projected coordinate system using feet units.
World File: a text file containing the mathematical information needed to project a raster image into a Projected coordinate system.

12. Map Projections
Map projection: used to represent the surface of Earth on a flat sheet of paper or orthogonal coordinate system
Map projections are subdivided into 2 categories:
Equal Area: area is preserved but azimuth angles are distorted (Transverse Mercator)
Equal Angle: azimuth angles are preserved but area is not (Mercator)

13. Map Projection Properties of ArcMap
ArcMap projects added feature classes (layers) on the fly based on the feature’s coordinate system and the project file coordinate system.
Raster images will be “rubber-sheeted” to fit the project file coordinate system.
If no coordinate system is selected for a project the first layer added to the project will set the coordinate system for the project file.
If a layer does not have an assigned coordinate system ArcMap assumes that the coordinates are in the current project system.

14. GIS Coordinate Systems
GIS systems handle map projections in 2 fundamental ways:
Geographic coordinates: the longitude and latitude values are retained in the project and projected to the screen or hard copy in a way decided by the software.
Projected coordinates: longitude and latitude values are used as defined by published systems (UTM, SPCS, etc.).
GIS systems can mix different systems together as long as the raw data is stored as coordinates, not as a raster file.

15. Projection Systematics in ArcMap
Topo Raster UTM NAD27
Excel GPS coordinates GCS
Parcel Boundary SPCS
All layers are seamlessly projected into UTM NAD83 coordinates
ArcMap Project
UTM NAD83
Plotted Map

16. Raster Data
Raster data is often used with GIS projects because they provide critical base map information (topographic base, DEM, Orthophoto, etc.)
To be used with GIS a raster file (.TIF, .JPG, .BMP, etc.) must have a “world file” that defines how the bit map fits into a projected coordinate system.
A common type of raster that we will be using often is a digital raster graphic (DRG) USGS topographic quadrangle that uses the UTM coordinate system
Units: meters
Map datum: NAD27 or NAD83
File format: TIFF
World file: TFW or TFWX

17. Raster World File
Contains projection transformation information that places raster in coordinate system (.tfw or .tfwx file):
3.81 (x dimension of pixel)
0.00 (rotation from x axis)
0.00 (rotation from y axis)
-3.81 (y dimension of pixel)
(x,y coordinates of upper left corner of raster)

18. Raster Map Projection UTM projection coordinates
Geographic coordinates

19. Yosemite Project
Georeference topographic base maps – i.e. create world files.
Digitize polygon, polyline (arc), point, and text annotation data.
Symbolize geometry
Calculate quantities important to project goals.
Plot final maps.