GIS Data Finder Frequently Asked Questions
How do I use the GIS Data Finder? -
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What is GIS?
What is the GIS Data Finder?
What is the difference between data layer sets (or data sets) and data layers (in the GIS Data Finder)?
What spatial data on campus is included in the GIS Data Finder?
How do I search the GIS Data Finder? (Data Finder Search Tips)
What is campus AFS?
How do I access spatial data available on the campus network (AFS)?
How do I access data I have found using the GIS Data Finder (How do I get these data)?
What is an ONYEN?
How do I get an ONYEN?
How can I view the data listed in the GIS Data Finder?
How can I learn more about GIS?
GIS Data Finder Home
What is GIS?
A GIS (geographic information system), also called geographical information system, is "a set of computer tools for collecting, storing,
retrieving at will, transforming, and displaying spatial data"..."for a particular set of purposes". A GIS provides users with the ability
to overlay map layers to custom-create maps and perform spatial analysis. See the links below for more introductory information.
Source: Burrough, Peter A., and Rachael A. McDonnell, 1998. Principles of Geographical Information Systems. Oxford University Press.
Geographic Information Systems, an informative poster from the USGS
http://erg.usgs.gov/isb/pubs/gis_poster/
What is GIS? From GIS.com
http://www.gis.com/whatisgis/index.html
What is GIS? From GIS Lounge
http://gislounge.com/library/introgis.shtml
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Library GIS Services Page]
What is the GIS Data Finder?
In order to create maps or perform spatial analysis using a GIS, you need spatial data. Davis Library Research and Instructional Services
actively collects spatial data from governmental sources (federal, state, and local) and commercial vendors. The GIS Data Finder is a
finding aid created to help patrons find and evaluate spatial data to use in their research.
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What is the difference between data layer sets (or data sets) and data layers (in the GIS Data Finder)?
Data layers are the individual layers of spatial data that can be used in a GIS. Typically, each data layer shows one type of feature
(such as roads, rivers, states, or elevation).
The spatial data collected by the Davis Library Research and Instructional Services usually comes in data sets, or compilations of data
layers. These spatial data sets are made up of data layers that either reference the same geographic area, pertain to the same area of
research, or both. An example of a data set that is made up of data layers that reference the same geographic area is the "North Carolina
Corporate Geographic Database" (NCGDB), which contains data for North Carolina. An example of a dataset that is made up of data layers
that pertain to the same area of research is "Better Assessment Science Integrating Point and Nonpoint Sources" (BASINS), which contains
data pertinent to hydrological research and water quality. An example of a dataset that is made up of data layers that both references the
same geographic area and pertains to the same area of research is "The Kachemak Bay Ecological Characterization", which contains data
pertinent to ecology research within the boundaries of The Kachemak Bay Research Reserve, Alaska.
The ultimate purpose in searching the GIS Data Finder is to find data layers that may be useful for research. Currently, the GIS Data Finder
does not contain data layer information for all of our data sets. Only our highest quality, most frequently requested data sets have data
layer information included.
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What spatial data on campus is included in the GIS Data Finder?
The GIS Data Finder includes the spatial data holdings of all libraries on campus, and the spatial data acquired by ITS. The libraries on
campus that have spatial data include the F. Stuart Chapin, Jr. Planning Library and the Geological Sciences Library. The GIS Data Finder
does not include spatial data held by individual professors, departments, or units on campus.
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How do I search the GIS Data Finder? (Data Finder Search Tips)
General Search Tips: All GIS Data Finder search strings are specific, non-case-sensitive and do not support Boolean logic (and, or, not).
All search fields on the search page are optional. The search string must match exactly to return a match- watch your spelling. Consider
the following search examples:
A search for "landsat7" returns no matches.
A search for "landsat 7" returns some matches.
A search for "landsat" returns many matches.
Step-by-step Tips:
Step 1 on the GIS Data Finder Search Page is a keyword search.
The term(s) typed in this search box will search for a specific string in the text in data layer fields:
name,
keywords,
publication year, and
spatial extent counties. Note that the spatial extent counties field is only valid for data layers in
the state of North Carolina. The term(s) typed in this search box also searches for a specific string in the following data set fields:
title,
keywords,
call number,
abstract,
publication year,
vendor/agency
, and
notes.
Step 2 on the GIS Data Finder Search Page limits the search by Geographic Area.
The first search box under step 2 is for Countries or Territories. The term(s) typed in this search box searches for a specific string in
the Countries/Territories field only. Click on the
View a list of Countries and Territories link to view a
listing of the country and territory names as they appear in the GIS Data Finder. Keep in mind that this is a specific search. Therefore,
searches for "us" will return results for the following countries/territories: Australia, Austria, Belarus, Cyprus, Mauritius, Russia,
Trust Territory of the Pacific Islands, and United States of America (U.S.,US, U.S.A., USA). If you are only interested in the United
States, using search terms "U.S." or "United States" would be more effective than "US".
The second search box is for State. This search option is only applicable when searching for data whose spatial extent is or is within the
United States. Don't forget that GIS Data Finder searches are specific, so searches for misspelled State names will not be effective.
Click on the
View a list of States link to view a listing of the country and territory names as they appear in
the GIS Data Finder.
Step 3 on the GIS Data Finder Search Page limits the search to data that are available on the campus network.
Not all of the spatial data held by the UNC-CH libraries is available on the campus network. Typically, only our most current, most
accurate, and most commonly requested data is available on campus AFS. Therefore, activating this search limitation will also remove older
data from search results.
Step 4 on the GIS Data Finder Search Page limits the search by license restrictions.
The default is set for current affiliates of UNC at Chapel Hill. Current affiliates have access to all of the spatial data held by the University Library.
Non-affiliates do not have access to all of the spatial data held by UNC-CH Libraries due to license agreements. License restrictions vary
by data layer.
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What is campus AFS?
"AFS is a distributed file system similar to a Windows or UNIX file server that allows Windows and UNIX computers to use the same file
space. Casual Windows and UNIX users will see little difference between working with files on the local hard drive and working with files
stored in AFS space. AFS can serve as a central place to store files for you or your department, which are then available from any computer,
Windows or UNIX, running the AFS client software. Additionally, AFS offers more advanced users enhanced capabilities to manage file
permissions, group access to directories, and disk quotas."
For more information, see the source of the above quote,
Introduction to AFS.
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How do I access spatial data available on the campus network (AFS)?
AFS is accessible to current affiliates of UNC at Chapel Hill only. Spatial data on the campus network can be accessed via uncAFS, the AFS Client, and Secure File Transfer Protocol (SFTP).
uncAFS - provides secure access to UNC AFS filespace using a web browser.
Patrons must login, then change the AFS path to the data desired. Please note that spatial data layers are generally composed of several different
files. You must transfer ALL files that make up a layer for the transfer to be
successful. For example, a data layer in shapefile format is composed of *at
least* three different files (shp, shx, and dbf). In order for a successful
transfer of this data layer, all of the files must be transferred.
Access via AFS Client:
On campus access: Means of access to the campus network differ for some computer
labs on campus, so you may need to consult with your computer lab administrator
to see how this is done. Most campus computers, including those in ITS labs, ITS
classrooms, and the public GIS machines in Davis Library, have the AFS Client
installed. The AFS client maps the root of AFS to the J: drive, and users'
personal AFS space to the H: drive after login. If your machine has these drive
mappings, once you have found a data layer that is available on campus AFS, all
you need to do to access the data is select the J: drive and then navigate the
path provided by the GIS Data Finder. For example: In order to add the data layer
"U.S. Counties (Detailed)", first find the location on campus AFS using the GIS
Data Finder. The path name for this example is provided in the GIS Data Finder
as: \afs\isis.unc.edu\data\gis\esri\dm02\data_maps3\usa\dtl_cnty.shp Then add
the layer to your GIS project by first selecting the J: drive, then navigating
through each of the folders listed in the path (each folder is separated with a
backslash \ ). isis.unc.edu data gis esri dm02 data_maps3 usa Finally, add the
data layer: dtl_cnty.shp
Off-campus access: Off-campus access can be as easy as it is on campus. All you
need to do is install the AFS client on your home computer. AFS Client installation
varies by operating system. For information on installing the AFS client, search ITS's
web page for "UNC AFS Client Installation Guide". The AFS client is available for
download from
ITS's Shareware Web Page.
Access via Secure File Transfer Protocol (SFTP):
If the AFS Client is not an option for you, Secure File Transfer Protocol (SFTP) is the
only other means of accessing data on the campus network. For more information
about SFTP, see ITS's document,
File Upload and Download (SFTP). Always use binary transfer mode to SFTP
spatial data. The SSH/SFTP Secure Shell application's default setting is auto
select mode- this moves shapefiles correctly.
If you need an SFTP client, SSH/SFTP Secure Shell is available from the
ITS Shareware Web Page.
Be forewarned that spatial data layers are generally composed of several different
files. You must transfer ALL files that make up a layer for the transfer to be
successful. For example, a data layer in shapefile format is composed of *at
least* three different files (shp, shx, and dbf). In order for a successful
transfer of this data layer, all of the files must be transferred.
An easier solution may be to burn the data you need to CD-ROM while on campus
and take the CD-ROM home. The public GIS machines in Davis Library Research and Instructional Services
have the AFS Client installed, and they have CD burners. UNC-CH Student Stores
sell CD-R discs.
If you can only access our spatial data collection from off campus and need
assistance, just
ask.
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How do I access data I have found using the GIS Data Finder (How do I get these data)?
The answer to this question varies depending on whether you are searching for
data layers or data layer sets (data sets). Simply put, data listed in the GIS Data Finder can be
obtained either from the campus network or from a library.
At this time, remote access to the Davis Library spatial data collection is
available for current affiliates of the University of North Carolina at Chapel
Hill only.
UNC affiliates can access spatial data on the campus network (AFS).
To access data layers, first check the "Location on Campus AFS" field. If there
is a path name, then the data is available on the campus network, and you can access
it from there. To watch a demo of this process, click
here.
For additional information, see,
How do I access
spatial data available on the campus network (AFS)?. If there is not a path name,
then the data is not on the campus network and may be found at the Library. Check the
"Parent Data Set Physical Location(s)" field to see which library has the data set (or data layer set) that
includes the data layer you need. Then check the "Parent Data Set Call Number" for the
call number of the data set that includes the data layer you need. You may then go to
the library to get the data set. Library staff will gladly assist you in locating the data.
To access data sets, first check to see if the data is on the campus network by looking
at the "Contains data layer(s)" field. If there are no data layers listed for that data
set, then it is not on the campus network. If there are data layers listed, then
the location on the campus network can be found by clicking on the individual layers
and checking the "Location on Campus AFS" field for each individual layer. There is
no "Location on Campus AFS" field for data sets because the path varies for each
data layer.
If the data set you want is not on the campus network, then check the "Physical
Location(s)" field to see which library has the data set you need. Then check
the "Call Number" for the call number of the data set you need. You may then go
to the library to get the data set. Library staff will gladly assist you in locating the data.
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What is an ONYEN?
ONYEN stands for Only Name You'll Ever Need. At UNC-CH, the ONYEN is used for
obtaining access to disk space (where many GIS data layers are stored), Internet
access, personal Web pages, and email. In order to access GIS data available
on the campus network, you must have an ONYEN. To obtain an ONYEN or find out
more about it, visit UNC-CH's ONYEN Services Page:
https://onyen.unc.edu/
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How do I get an ONYEN?
Only those affiliated with the University of North Carolina at Chapel Hill
(current faculty, staff or students) can get an ONYEN. To obtain an ONYEN, go
to the ONYEN services Page:
https://onyen.unc.edu/
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How can I view the data listed in the GIS Data Finder?
In order to view or manipulate any of the data listed in the GIS Data Finder, you must use GIS software, image processing software, or other
software that can read GIS data. UNC-CH has site licenses for GIS software. Read more about the software available to UNC-CH
affiliates at:
http://its.unc.edu/gis/software.html
Note: UNC-CH affiliates include current faculty, staff, and students.
Non-UNC-CH affiliates may download ArcReader, a free GIS data viewer, from ESRI
at the following web page:
http://www.esri.com/software/arcgis/arcreader/index.html.
Non-UNC-CH affiliates are welcome to come to Davis Library and use our GIS
software (for non-commercial uses), provided that no copies of the software are
removed from the library.
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How can I learn more about GIS?
In addition to formal UNC-CH courses that incorporate GIS, there are also short
courses and online training modules available. For more information, see:
http://www.lib.unc.edu/reference/gis/training.html
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