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Metadata Understanding the Value and Importance of Proper Data Documentation Exercise 2 Reading a Metadata File Exercise 3 Using the Workbook Exercise 1 The Hunt for Good Metadata Exercise 4 Using Metadata to Determine Suitability Exercises
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Metadata Exercises Exercise 1 – The Hunt for Good Metadata For this exercise, we will be using the Federal Geographic Data Committee (FGDC) Geospatial Data Clearinghouse to search for data of interest. The Geospatial Data Clearinghouse is a collection of over 400 metadata servers (called nodes) that house metadata describing data, primarily for use in Geographic Information Systems (GIS), image processing systems, and other modeling software. These data collections can be searched through a single interface based on their metadata. To access the clearinghouse, go to http://www.fgdc.gov. This is the main page for the FGDC. On the left side of the page, click on the clearinghouse link. This takes you to the clearinghouse web page. Clicking on the top link in the center of the page, "Search for Geospatial Data", will allow access to the search system. You should see a picture of the globe showing six gateways. Choose one of these gateways (they all lead to the same collections of metadata). On the next page, you will be presented with four options: Use the NSDI Search Wizard to "smart select" servers and data Search Clearinghouse sites using map interface with place names Search Clearinghouse sites using place names Check status of participating Clearinghouse collection servers The top 3 are search options. The first option allows you to search for metadata by topic area. The NSDI Search Wizard bins the metadata nodes into 21 topic areas based on the 'flavor' of metadata each node houses. The next two search interfaces are fairly similar; the main difference is that the second option allows the user to define a geographic bounding box of the area of interest on a map. The last option allows the user to check on the operational status of the individual clearinghouse nodes. Take a few minutes to examine each of these 4 options. As you are experimenting with the search interfaces, observe how well each different interface works. Test each for speed in returning results, and think about how intuitive each option is for constructing a search query. When you have finished exploring these different search interfaces, choose one and begin a search for data that you are interested in. You may have a particular need related to a current project you are involved with. If you are not currently working on a project that requires you to find data, then search for data that is of interest to you.
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Metadata Exercises Exercise 2 – Reading a Metadata File In this exercise, we will use a metadata file that you found from the clearinghouse search system exercise. Your record may or may not provide all the information asked for here. What you should focus on while working through this exercise is whether or not the record you have chosen provides an adequate level of information to be of use to a user. What's the title of the data set? What are the bounding coordinates? What is the presentation form of the geospatial data? Why was this data set created? Find and list three place keywords. Who created the data set? How complete is the data? How reliable are the data? What problems remain in the data set? What spatial reference method is used to represent the data? List three data set attributes and the definition of each. How can someone get a copy of the data? Who distributes it? What sources were used to develop this data set?
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Metadata Exercises Exercise 3 – Using the Graphical Production Rules with the Workbook In this exercise, we will interpret a metadata file that you've found using the clearinghouse search system in exercise 1. Using the graphical representation of the production rules and the CSDGM workbook, locate the answers to the following questions. Where is the definition for the data element West Bounding Coordinate? Where is the definition for the compound element Description? What data elements make up the compound element Description? What is the domain for the data element Process Date? What is the domain for the data element Address Type? Name one compound element from Section 2 that can be repeated. Name one data element from Section 8 that can be repeated. Is the data element Abstract mandatory? Is the data element Ellipsoid Name mandatory? What is the short name for the compound element Direct Spatial Reference Method? What is the data type for the data element Abscissa Resolution? __________________________________________________
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability Background You have been hired to head up the newly formed Office of Coastal Management in Cumberland County, Maine. Unfortunately, Cumberland County has not been using GIS technology and has no digital data available for you to use, and they have also spent most of the first year’s budget on your salary and technology purchases. The county commissioners want to see some GIS products from you in a few weeks when they bring you before the town meeting. What are you going to do!?! Not panic, that’s what. Being the intelligent coastal management professional you are, you know where you can obtain data that will wow the commissioners and showcase your GIS skills. After that you can get down to the business of preserving the pristine coastline and abundant natural resources, the real reason you took this job. You have downloaded the data that you needed to show your superiors you could get the job done. Now you need to make sure the data remain useable for years to come. You also want to make sure you will have the detailed information needed to share your data with other organizations. To do this, you need to look closely at the metadata and make sure it is up-to-date and correct. As the county’s coastal manager, you have several project proposals on your desk. You need to review each to see if the data you have are appropriate. You will analyze the appropriate metadata and use it to decide if the data are suitable for these projects. Goal After hearing the lecture and working through the exercises, you will be able to read and understand the information metadata provides about data. Objectives 1. Import metadata for previously downloaded data 2. Analyze the metadata 3. Determine if the data are suitable for different projects NOTE: The data used for this exercise has been provided. It is assumed you have already downloaded and converted it to fit your needs. The data are shapefiles of the Maine coastline, and are located in Exercises/Coastal_GIS/CSC_meshr, directory on your workshop CD. Below is a list of the directories to be used. CSC_meshr – Downloaded from http://www.csc.noaa.gov/ PSU_meshr – Downloaded from http://www.maproom.psu.edu/dcw/ SPO_meshr – Downloaded from ftp://spo.nos.noaa.gov/datasets/shoreline
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability Summary of Process Steps 1.Explore Different Types of Metadata – import associated metadata files for the shoreline data that you downloaded in the last exercise 2.Analyze Metadata – use metadata to answer specific questions about the data previously downloaded 3.Use Metadata to Determine Suitability – use the metadata to assess the data’s usability in different scenarios ArcCatalog Internet Explorer Tools to Use Data Spatial data required for this exercise is provided on the workshop CD under ‘Exercises/Coastal_GIS’.
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability 1. Explore different types of metadata Many data sets do not have dedicated metadata per se, but instead have information about the data set that can be accessed at the location where you downloaded the data. This means that you may have to do a little clever detective work. Only one of the data sets you downloaded has an associated metadata file that can be viewed in ArcGIS. For the other two files, you will have to go back on the Internet to find out more information about the data. You will start with the data that you downloaded from the NOAA Coastal Services Center. Fortunately, this data set does have associated metadata. It even conforms to FGDC standards. Open ArcCatalog by clicking on Start > Programs > ArcGIS > ArcCatalog. In the table of contents, navigate to the Exercises/Coastal_GIS/CSC_meshr data folder, located on your workshop CD. Click on the meshrpl data set and then click on the Metadata tab. On the Metadata toolbar, set the stylesheet to FGDC Classic. Sometimes you might download data that has associated metadata in a.met text format. In order to view that metadata, you will need to use the import function of ArcCatalog. To import metadata, click on the Import metadata button. In the subsequent dialog, set the format to FGDC CSDGM (TXT) and click on the Browse button. Navigate to your data folder and select the meshr.met file (NOTE: you may have to set the file type to All Files (*.*)). Click Open and then OK. There are many reasons why some data sources do not have associated metadata. Sometimes, the data must be exported from a larger data set in an automated process. Depending on the complexity of the site, you may not be able to get a customized metadata record for the data. Did You Know?
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability 1. Explore different types of metadata (continued) Minimize, but do not close, ArcCatalog. Open Internet Explorer. Navigate to the following site: ftp://spo.nos.noaa.gov/datasets/shoreline The shoreline data sets from the Special Projects Office (SPO), downloaded earlier and found in the Exercises/Coastal_GIS/SPO_meshr directory on your workshop CD, do not have an metadata file. There is, however, a text file that contains information on the data sets contained on the site. Double-click on readme.txt. Review the document. Once you have finished, click File > New > Window. In the new window, enter the following URL: http://www.maproom.psu.edu/dcw/. Click on the About DCW link. (Hint: Make sure to explore some of the other links as well.) This document contains pertinent information about the Digital Chart of the World shoreline data that was downloaded and is found in the Exercises/Coastal_GIS/PSU_meshr directory on your workshop CD. The downloaded data in this file is the shoreline data for Maine, clipped from the larger data set represented by the DCW. Keep both of the Internet Explorer browser windows open because you will use them in the next step.
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability 2. Analyzing metadata In this part of the exercise, you will take a closer look at the metadata for all of the downloaded data sets. You will learn what to look for and where it is located within the metadata. This will provide you with an invaluable tool for finding data that will be useful to you in your future GIS projects. For each of the data sets, answer the following questions: DCWSPOCoastal Services Center What is the horizontal datum of the data? What is/are the scale(s) of the data? How many sources do the data have? What is the publication date of the data? Who is the publisher of the data? What are some of the major attributes of the data?
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability 3. Determine suitability Now that you have taken a closer look at the data and have a better understanding of exactly what each set represents, it is now time to use that knowledge. You have three project requests on your desk that need to be considered. The first request is for general regional mapping. The state would like some general information about the coast for its Web site and wants you to provide shoreline data from your county. Based on what you learned from the metadata, what data set would be best for this purpose? __________________________________________ Why? ___________________________________________________________________________________ Next, the county has just passed new zoning laws that restrict building in and along the coastal zone. One of the main accomplishments is the establishment of a setback ordinance. The county hopes to preserve its shoreline and reduce costs after storms by limiting construction near the water’s edge. What data would work well for this project?____________________________________________________________________________________ ___________________________________________________________________________________________ Why? ______________________________________________________________________________________
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Metadata Exercises Exercise 4 – Using Metadata to Determine Suitability 3. Determine suitability (continued) Finally, after several severe winter storms over the past few years and a great deal of property loss, the citizenry and the county commissioners want a beach erosion study completed by your office. Which data set would you use to complete such a study?________________________________________________________________________ ___________________________________________________________________________________________ Why? _____________________________________________________________________________________ Keep in mind all you know about the different data sets. Think about size, draw time, resolution, accuracy, etc. Do you think you have the right data for these projects or would you like different data? _____________________________________________________________________________________________ _____________________________________________________________________________________________ _____________________________________________________________________________________________ Close all applications.
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Metadata Exercises In this exercise, you began by understanding what metadata really is. Then, you learned about the value of metadata and examined the different metadata formats available within ArcCatalog. You were then asked to import existing metadata in a usable format using the ArcCatalog software. Next, you were asked to analyze the metadata and answer questions that could be found within the metadata itself. Finally, you used the metadata to determine the usability of the specific data for different scenarios. Exercise 4 - Using Metadata to Determine Suitability Exercise Summary
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Metadata Exercises Exercise 4 - Using Metadata to Determine Suitability Page 42 DCW Shoreline (Ponet) SPO Shoreline (ec80_05) Center Shoreline (Meshrpl.shp) What is the horizontal datum of the data? World Geodetic System 1984NAD 1983NAD 1927 What is/are the scale(s) of the data? 1:10000001:700001:5000; 1:10000; 1:20000 How many sources do the data have? OneTwoOne What is the publication date of the data? March 1997August 24, 19941986 Who is the publisher of the data? Defense Mapping AgencyNOSNOAA What are some of the major attributes of the data? Polygonal boundary for the state of Maine NOS chart catalog number from which the arcs were captured Shoreline; dike or levee; pier, ramp, dock Answers to Exercise Questions Page 43 Regional MappingMeshrpl.shp Most complete and accurate data set, much larger scale than other data sets. Setback OrdinanceMeshrpl.shp Once again, there is much greater detail of the shoreline in this shapefile, which would allow for more accurate delineation of the shoreline. Page 44 Beach Erosionec80_05 This data set covers the entire coast of Maine and would allow for the analysis needed to map beach erosion
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Metadata Exercises Discussion: Suitability of the Data Which data set did you choose for each project? List the pros and cons of various resolutions of data. ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________
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