Geography 160Geography 160Project 3Project 3Using Map Data and Using Map Data and Integrating it into GISIntegrating it into GIS

By Jerrica, Daniel, and AaronBy Jerrica, Daniel, and Aaron

Project 3 OverviewProject 3 Overview

Find, download, and view map data Find, download, and view map data of an area of interest (your of an area of interest (your

hometown) hometown) Make 3 map data sets and one map Make 3 map data sets and one map

overlay with comments for each of overlay with comments for each of themthem

IntroductionIntroduction

You will be using USGS map data and You will be using USGS map data and ArcMap to learn how information from ArcMap to learn how information from aerial photography, land elevation, aerial photography, land elevation, and landmarks/features can be used and landmarks/features can be used and interpreted. and interpreted.

The information you will be applying is The information you will be applying is used by US, state, and even local used by US, state, and even local government for things from government for things from development to planning.development to planning.

Introduction of the 3 Introduction of the 3 Map Data TypesMap Data Types Digital Elevation Model (DEM)Digital Elevation Model (DEM)

– A raster representation of the terrain’s surfaceA raster representation of the terrain’s surface– Accuracy varies depending on the level of DEMAccuracy varies depending on the level of DEM

Digital Line Graphs (DLG)Digital Line Graphs (DLG)– Vector representations of most features and Vector representations of most features and

attributesattributes– Warranted to be free of topological defectsWarranted to be free of topological defects

Digital Orthophoto Quarter Quadrangle Digital Orthophoto Quarter Quadrangle (DOQQ)(DOQQ)– Raster images of rectified aerial photosRaster images of rectified aerial photos– Error is caused by the rectification processError is caused by the rectification process

Digital Elevation Model Digital Elevation Model (DEM)(DEM) A DEM is a raster representation A DEM is a raster representation

of a terrain surface. More of a terrain surface. More specifically, a DEM is a data specifically, a DEM is a data product of the U.S. Geological product of the U.S. Geological Survey Survey

A DEM is a raster illustration of A DEM is a raster illustration of the Earths’ surfacethe Earths’ surface

What a DEM Looks LikeWhat a DEM Looks Like

What a DEM DoesWhat a DEM Does

Shows the elevation of an areaShows the elevation of an area Shows land characteristics like Shows land characteristics like

lakes and Mountainslakes and Mountains

DEMDEM

Go to http://seamless.usgs.govGo to http://seamless.usgs.gov Click on“View and Download United Click on“View and Download United

States data”States data” With your mouse, draw a square around With your mouse, draw a square around

the area you choosethe area you choose Check NED Relief (under the elevation Check NED Relief (under the elevation

tab)tab) Click on “define downloads area”Click on “define downloads area” Once you target the area click Once you target the area click

“download”“download”

DEMDEM

Open the file and click “use evaluation Open the file and click “use evaluation version”version”

Highlight all the files and click “extract”Highlight all the files and click “extract” Extract the files to the DEM folder you Extract the files to the DEM folder you

made and then click OKmade and then click OK Open ArcMapOpen ArcMap Go to Add Data and find your mapGo to Add Data and find your map Save this file to you WWW.Save this file to you WWW.

Uploading Your DEM Uploading Your DEM MapMap Once your map is uploaded, hold Once your map is uploaded, hold

down alt and print screen so you down alt and print screen so you will have a screen shot of the will have a screen shot of the program to put on your websiteprogram to put on your website

Go to Start>Accessories>PaintGo to Start>Accessories>Paint Go to Edit and paste your mapGo to Edit and paste your map Save it in your WWW folderSave it in your WWW folder

DLGDLG

Digital vector representations of Digital vector representations of cartographic informationcartographic information

Data files are derived from either Data files are derived from either aerial photos or cartographic aerial photos or cartographic sourcessources

Can be converted manually or Can be converted manually or digitallydigitally

DLGDLG

Composed of nodes, lines, and Composed of nodes, lines, and area identifiersarea identifiers

Lines connect nodes and the solid Lines connect nodes and the solid areas they create are identified areas they create are identified with area identifierswith area identifiers

DLGDLG

Features that can be represented Features that can be represented are:are:

BoundariesBoundaries HydrographyHydrography TransportationTransportation Man made featuresMan made features U.S. Public Lands Survey SystemU.S. Public Lands Survey System

DLGDLG

There are 3 scales of DLGsThere are 3 scales of DLGs Large Scale (7.5 minutes)Large Scale (7.5 minutes)

– 1:20,000, 1:24,000, 1:25,0001:20,000, 1:24,000, 1:25,000 Intermediate Scale (30X30, 30X60 Intermediate Scale (30X30, 30X60

minutes)minutes)– 1:100,0001:100,000

Small Scale (52 rectangular units of Small Scale (52 rectangular units of U.S.)U.S.)– 1:2,000,0001:2,000,000

Steps to making a DLGSteps to making a DLG

1: Open the website 1: Open the website http://arcdata.esri.com/data/tiger2000/tiger_download.chttp://arcdata.esri.com/data/tiger2000/tiger_download.cfmfm

2: Select your state2: Select your state 3: Select your county3: Select your county 4: Click 3 or more features you 4: Click 3 or more features you

want.want. 5: Click to download the files5: Click to download the files

Steps to making a DLGSteps to making a DLG

6: Create a folder (a good place is on 6: Create a folder (a good place is on your network drive)your network drive)

7: Locate the ZIP file you downloaded 7: Locate the ZIP file you downloaded in Step 5 and extract it to the file you in Step 5 and extract it to the file you just created in Step 6 (press Trial just created in Step 6 (press Trial Version)Version)– Once extracted you may have to extract Once extracted you may have to extract

files within your folder that you createdfiles within your folder that you created

Steps to making a DLGSteps to making a DLG

8: Once all of the files are unzipped, 8: Once all of the files are unzipped, open ArcMapopen ArcMap

9: Select “File”, “Add Data”9: Select “File”, “Add Data” 10: Go to the folder you created 10: Go to the folder you created

and select all of the files you and select all of the files you unzippedunzipped

A complete DLG!A complete DLG! 11: Press “Alt”+“PrintScreen” with 11: Press “Alt”+“PrintScreen” with

the ArcMap window up.the ArcMap window up.

Steps to making a DLGSteps to making a DLG

12: Open Paint and go to “Edit” 12: Open Paint and go to “Edit” and click “Paste”and click “Paste”

13: Save this image into your 13: Save this image into your folderfolder

DLG ExampleDLG Example

Another DLG ExampleAnother DLG Example

DLG SourcesDLG Sources

A good place to learn about DLGs is A good place to learn about DLGs is http://edc.usgs.gov/guides/dlg.htmhttp://edc.usgs.gov/guides/dlg.htmll

or or http://www.ctre.iastate.edu/Researhttp://www.ctre.iastate.edu/Research/bts_wb/cd-rom/spatial/dlg.htmch/bts_wb/cd-rom/spatial/dlg.htm

DOQQ MapsDOQQ Maps

(digital orthophoto quarter (digital orthophoto quarter quadrangles)quadrangles)

Raster images created by scanning black and white vertical aerial photographs into a computer

Image is digitally warped to correct distortion in terrain relief and camera tilt in a process called orthorectification

Scale is uniform throughout the image. Therefore it is possible to measure distance directly on the map.

DOQQ Accuracy and DOQQ Accuracy and ErrorError

DOQQ maps have a scale of DOQQ maps have a scale of 1:12,0001:12,000

90% of all points lie within 20 feet 90% of all points lie within 20 feet of there actual positionof there actual position Error is created in the Error is created in the

orthorectification processorthorectification process

Uses of DOQQ mapsUses of DOQQ maps

Editing and revising vector Editing and revising vector planimetric dataplanimetric data The State Department of The State Department of

Transportation uses these maps to Transportation uses these maps to update road data. Road data is update road data. Road data is plotted on DOQQs and then can be plotted on DOQQs and then can be revised to show new road layoutsrevised to show new road layouts

Information found in the online text: Module 3; Air photos and Information found in the online text: Module 3; Air photos and photogrammetry; USGS DOQphotogrammetry; USGS DOQ

Creating a DOQQCreating a DOQQ

1.1. Go to http://seamless.usgs.gov Go to http://seamless.usgs.gov

2.2. Zoom into your area make it small Zoom into your area make it small

3.3. Uncheck all boxes under the Uncheck all boxes under the elevations tab from both layers elevations tab from both layers tabs (display and download)tabs (display and download)

4.4. Under the download tab…Under the download tab…orthoimagery….select 1m B&W orthoimagery….select 1m B&W DOQQ DOQQ

Continued DOQQ Continued DOQQ MakingMaking

5. Select the “define download 5. Select the “define download area” button on the left side of area” button on the left side of the screenthe screen

6. Download, extract, and upload 6. Download, extract, and upload to arcmap the same as with the to arcmap the same as with the DEM map. DEM map.

1.1. Because DOQQ files are large Because DOQQ files are large delete them after usedelete them after use

DOQQ ExampleDOQQ Example

ConclusionConclusion

DEMDEM– Illustrates elevationIllustrates elevation– Raster illustration of the terrainRaster illustration of the terrain

DLGDLG– Uses lines, and nodes to represent Uses lines, and nodes to represent

different areas.different areas.– Used for planning and analysisUsed for planning and analysis

DOQQDOQQ– An actual image of the area you are An actual image of the area you are

looking atlooking at– Also good for planning and analysisAlso good for planning and analysis

SourcesSources

DEM and DOQQ maps DEM and DOQQ maps – http://seamless.usgs.govhttp://seamless.usgs.gov

DLGDLG– http://arcdata.esri.com/data/tiger2000/http://arcdata.esri.com/data/tiger2000/

tiger_download.cfmtiger_download.cfm

Map InformationMap Information– Online text: Online text:

http://training.esri.com/Courses/geodata_Arhttp://training.esri.com/Courses/geodata_ArcGIS/index.cfm?c=31 cGIS/index.cfm?c=31

Further QuestionsFurther Questions

Any questions can be emailed toAny questions can be emailed to– jmb810@psu.edu jmb810@psu.edu – dlh281@psu.edudlh281@psu.edu– ajk5128@psu.eduajk5128@psu.edu

This slide show will be posted on This slide show will be posted on our Personal websites for access our Personal websites for access to instructionsto instructions