The Virginia. your spatial data! (i.e. their. data layers) carrot (or. governments. but many. are looking. for data from.

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1 The Virginia Geospatial Metadata Clearinghouse GISData.Virginia.Gov is Virginia's online portal for discovering and sharing geospatial dataa and metadataa for the Commonwealth. St GISData.Virginia.Gov is a service of the Virginia Geographic Information Network, a part of the Virginia Informationn Technologies Agency. State agencies are required, through the code of Virginia, to report their geospatial data assets (i.e. their data layers) to the Virginia Geographic Information Network. Of course, there is no carrot (or stick!) to help enforce this mandate, so it is based on good will! Local governments can voluntarily provide their spatial metadataa to the Virginia Metadata Clearinghouse as well, but many of them do not. Basically, this is a good site too initiate a search, when you are mining for GIS data, especially data associated with state agencies. Note that the VA Geospatial Metadataa Clearinghouse only contains metadata for Virginia. If you are looking for data from outside the state, then this is not the site for you Also, remember (from last year) that metadata is information about t the spatial data. Metadata is not spatial data. It can provide you with information (including a point of contact or a downloadd source) for your spatial data! The Virginia Geospatial Metadata Clearinghouse is located here: It looks like this! Thee Virginia Metadata Clearinghouse Page 1

2 To use the clearinghouse, simply search on your data layer (roads, water, etc.). In the example above, I began my search for data on roads Note thatt my initial search (roads) resulted in 76 records found. Most of these are not what I am looking for. Imagine downloading 76 GIS files, just to finally find the one file that best suitss my particularr needs. Uggh. This would be painful and veryy time consuming! We ve all got other fish to fry! This is the value of metadata! We can scan through and read about the spatial data, before ever downloading a single spatial dataa file! The other great characteristic of a metadata clearinghous se, is that we can also search on the metadataa records (by keyword, organization, the date of the data, geographic extent of the data etc.). We can use these searching tools to channel our time and efforts and become more efficient! Also note that for each metadata record provided, you have 2 or three options. You can: a. View Details: View a summary of the metadata b. View All Metadata: View the entire metadata file c. Download Data: Download the spatial data (notee that this option is not available with ever metadataa record ) Thee Virginia Metadata Clearinghouse Page 2

3 So let s return to this example. I am searching for a road network for Virginia. I suspect that the Virginia Department of Transportation is responsible for developing this road network, or at least must have some hand in the process. Therefore, I am goingg to refine myy search, and search for Road VDOT. Refine your search options here.. By refining my search, I was able to narrow my search to just 1 layer! You don t always get this lucky! Thee Virginia Metadata Clearinghouse Page 3

4 After reviewing the metadata, I have determinedd that I this is,indeed the layer that I have been looking for. This particular record allows me to download the data. There is not always a download option. If there is not a download option then I will need to read the metadata and contact the person who is responsible for disseminating the data. To download and use the data, simply download, uncompress (extract) and add the layer into ArcMap! You will need to uncompress these files before ArcGIS will bee able to read them! To uncompress these downloaded Extract All option. files, simply highlight and right click on the file, and select the You will then be prompted to provide a location where the unzipped files will be stored. Thee Virginia Metadata Clearinghouse Page 4

5 Click <OK> and voila! Your files have unzipped. You can now open ArcMap and use the <Add Data> button! ArcMap! You are ready to startt working in Thee Virginia Metadata Clearinghouse Page 5