Welcome to Drew University’s Spatial Data Center, a part of the Environmental Studies and Sustainability Program, sponsored by generous grants from the Andrew W. Mellon Foundation and NASA. This website is designed to help you get started with Geographic Information Systems (GIS). Everything from choosing software, downloading data, and performing spatial analysis is covered. As part of the EPA-TRI University Challenge, the tutorials on this site specifically introduce the EPA Toxics Release Inventory (TRI) database; however, the instructions are designed to facilitate GIS use in any field of inquiry.
|GIS Tutorials||ESRI ArcGIS||Quantum GIS|
|Download and Add Data||ArcGIS 10.2||QGIS 2.0.1|
|Modify Data Display||ArcGIS 10.2|
|Join Databases||ArcGIS 10.2|
|Query and Select Data||ArcGIS 10.2||QGIS 2.0.1|
|Spatial Joins||ArcGIS 10.2||QGIS 2.0.1|
|Summarizing Tabular Data||ArcGIS 10.2 (New Jersey)|
|Tabular Data, Example 2||ArcGIS 10.2 (Florida)|
Use Google Fusion to create and share web maps like this one:
For a brief introduction to the EPA’s Toxic Release Inventory (TRI) and GIS: Download all QGIS Tutorials.
Also, all materials for the spring 2014 GIS course, dedicated to the spatial analysis of the TRI, as well as the Summer 2014 and Fall 2014 Introduction to GIS and Advanced GIS courses are publicly available on our course Google Drive Site (2014), Spring 2015 course materials are also available (currently in progress).
Click here for tutorial videos that guide you through downloading, extracting, adding and analyzing Toxics Release Inventory (TRI) data in a GIS.
Web GIS Applications
A growing number of spatial data tasks can be accomplished with web GIS applications. These include applications that work through your web browser, like Google Maps, through freely downloadable software, like Google Earth, or through specialized web mapping sites, hosted by specific sources, like the National Library of Medicine’s TOXMAP. To generate a map or identify locations of the facilities regulated by the EPA, and included in the Toxic Release Inventory, you have multiple choices of web-based applications. Some of these include the EPA’s TRI Website, TOXMAP, ArcGIS Online, and Google Earth.
EPA TRI Website
On the front page of the EPA’s TRI Website, you can access information on regulated facilities in the “Learn about Toxic Chemicals in Your Community” map. By submitting address information, the map zooms into the area entered and flags nearby facilities. Clicking on the facilities will retrieve more information, such as the name of the facility, and updated records of the releases for that facility.
TOXMAP is an online GIS application that allows you to investigate TRI facilities across the country, types of releases by facility, changes in releases over time, and the relationship between facilities and other demographic and health correlates. TOXMAP is hosted by the National Library of Medicine and integrated with databases on the health effects of toxic releases. A tutorial on how to identify and interpret information on TOXMAP is posted.
The company ESRI hosts a website called ArcGIS Online, which allows you to create your own maps, like this one, using web services or by uploading data that you have. There is a great deal of flexibility in producing the map that you desire. The existing ArcGIS Online layers will allow you to map point locations of EPA regulated facilities. To use ArcGIS Online, you will need to create a user name and password for the site.
Google Earth is a widely used platform to study spatial data. It has particular appeal in its engaging graphics and interface. The EPA releases data in Google Earth format. To use this data, you will first need to download and install Google Earth. Next, you will need to download the TRI dataset for Google Earth (look for the national .kmz file). Once you have both you can open the TRI database in Google Earth.
Stand Alone GIS Software Packages
Though Web GIS features are becoming increasingly diverse, complex, and customizable, many analysts wishing to design their own maps, generate their own specific queries, and conduct analysis with a diversity of data layers prefer to use stand alone GIS software packages. Though all GIS software integrates the web to some degree, stand alone packages provide downloadable software that allows users the most flexibility in managing, creating, visualizing and analyzing their own data. A variety of commercial and open source options are available, and the choice of which package to select depends on the user’s resources, needs and experience. Some of the most common commercial packages include ESRI ArcGIS, MapInfo, and AutoCAD Map 3D. Open source packages, which are free, include Quantum GIS, Diva GIS, Map Window, and GRASS.
Commercial GIS Packages
Commercial packages typically come with a large suite of analysis tools and customizable templates and platforms. ArcGIS is commonly used in government and industry to produce publication quality maps, customized web maps, and to input, track, and analyze large volumes of spatial data. Commercial packages typically provide users with access to customer service and training programs on how to use the software.
Open Source GIS Packages
Open source software packages have the distinct advantage of being free. They are also highly customizable, with open access to software design and code. Packages like Quantum GIS work across platforms (not just on Windows, as is the case with ArcGIS). There are fewer analysis tools and display options, but making GIS software globally accessible is tremendous benefit.
The sections in this tutorial will guide you through the process of working with EPA spatial data in both ESRI ArcGIS and Quantum GIS.
Specialized Analysis Software
Last, there are very specific GIS tools for very specialized types of analysis that are also important. For example, if you would like data on how specific toxins travel through the air, ground, or water, you will need to probably need to gather your own data and create a custom project. Several EPA tools are designed to help with various tasks in this endeavor. One example of a specialized software for TRI data is the Risk-Screening Environmental Indicators (RSEI) program, which allows users to identify and compare health risks generated from TRI emissions. Because the data are tied to regulated facilities, it is spatial in nature, and functions as specialized GIS software. Other specialized GIS software allows you to examine correlations over space (GeoDa), and space and time (STARS). To review, for easy and quick access to data, web GIS tools will probably cover your basic needs. For more customization of the display, and control and analysis of the data, stand alone GIS packages, and some training in GIS will meet your needs. For very specific data and analysis tools, specialized software may exist, or you may need to customize your own tools for the job.
For questions or requests, please contact Lisa Jordan, email@example.com.
Spatial Data Sources
There are two data models that operate in a GIS: vector data (point, line, and polygon, e.g. cities, roads, and country boundaries) and raster data (often satellite imagery, but any data saved and arranged in a gridded format). Both data models are an essential part of GIS analysis.
- NASA’s Earth Observing System: massive collection of imagery and important earth observation data
- Natural Earth: a useful collection of global boundaries
- IPUMS: global census microdata
- Data.gov: all types of geospatial data, a federal clearinghouse of information
- USGS National Map: elevation, imagery, land cover – an essential resource
- National Historic GIS: current and historic census data for the US
Most states in the US maintain their own geospatial data warehouse. For New Jersey, see the New Jersey Geospatial Information Network.
Environmental Data – Relating to EPA’s Toxic Release Inventory
For questions or requests, please contact Lisa Jordan, firstname.lastname@example.org.
Download TRI Data
Extract Spatial Data/h4>
Add Data to ArcGIS/h4>
Join Attribute Data in ArcGIS
Export Joined Datasets
Clip National Dataset by State Layer
Add and Calculate New Fields (Variables)
Use Query to Select Records
Export Selected Records
Quick Thematic Map with Points
Change Symbol Size and Transparency
QGIS Video Tutorials
These videos introduce Quantum GIS and EPA TRI data. They run through the written tutorials, step-by-step. No sound was used for these videos, which are best viewed as full screen, 1080HD.
Quantum GIS – Tutorial 1, Part 1
Quantum GIS – Tutorial 1, Part 2
Quantum GIS – Tutorial 2, Part 1
Quantum GIS – Tutorial 2, Part 2
Quantum GIS – Tutorial 2, Part 3
Quantum GIS – Tutorial 3
GIS Tutorials Archive
Below you will find links to How-To documents in online and PDF format that teach specific skills with GIS programs. Accompanying these tutorials you may find files to help you complete each tutorial and animated demonstration videos. For help with these tutorials, to request an appointment or to request the creation of a specific tutorial, contact GIS Specialist Lisa Jordan x3740 (email@example.com).
Links to a number of GIS tutorial resources for ArcGIS, ArcPad, Trimble GPS Units, and GIS data management.
Instructions for faculty/staff and students for downloading ArcGIS and Google Earth. Information about other GIS programs, data resources, tutorials, and instructional materials.
Google Earth Tutorials
Exercises for learning to use Google Earth. Recommended for courses and projects in which no data analysis is required.
A condensed set of how-to instructions for beginning to work with Google Earth.
Living tutorial documents in uKnow help students, faculty, and staff use Trimble GPS units with ArcPad 8 software to create dynamic map projects.
A set of instructions for using the Trimble GPS unit with ArcPad 8 software to collect latitude and longitude coordinates for map projects.
Instructions for changing the way the symbols used to represent latitude and longitude points in your map project using ArcPad 8 on the Trimble GPS unit.
The courses projects and programs described on these pages are not supported by government funds. Major support from the Andrew Mellon Foundation is gratefully acknowledged.
This document is recommended for anyone downloading ArcGIS software onto a computer that is more than a year old. Though the title suggests that they are only for laptops, these directions are recommended for Drew desktop computers as well.
Basic instructions for navigating the ArcGIS interface, adding shape files and data to a map document, designing and symbolizing data so that it can be read by users.
Geocoding allows you to add street addresses as data points to your maps. In this tutorial, users learn to use online map documents from the ESRI GIS Server services, access ESRI’s Geocoding database, import addresses in a .csv file to their map document, and use the geocoding function in ArcMap to code the uploaded addresses to show up on their map.
Measuring distances between points can provide useful data for a wide variety of analyses. Users will learn to create layers of geocoded addresses and then use the analysis capabilities of Hawth’s Tools to measure distances between those addresses. Users will also learn to create new data columns within layers and write a calculation script that automatically converts calculated distances from one unit of measurement to another. Designed for users who have already taken the Geocoding Tutorial.
Cartograms are a method of displaying geospatial data as totals, wherein data are displayed with both color and area as a function of their values. Cartograms are analogous to pie charts in which the slices of the pie are geographic regions rather than wedges. Maps that display data as cartograms are quite dramatic and will provoke reactions and spur dialog in the classroom.
This tutorial teaches you how to save data layers and map documents into a format that can be imported and used in Google Earth.