1. BACKGROUND HOW TO VIEW THE CHS NONNA-100 BATHYMETRIC DATA: a) View in the FGP Map Viewer:... 2

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1 This is a guidance document to assist users with navigating the Federal Geospatial Platform (FGP) to view, query and download the Canadian Hydrographic Service s (CHS) Non-Navigational (NONNA-100) Bathymetric Data. Table of Contents 1. BACKGROUND HOW TO VIEW THE CHS NONNA-100 BATHYMETRIC DATA:... 2 a) View in the FGP Map Viewer:... 2 b) View using the Web Map Service (WMS) connection in other applications: CHS NONNA-100 BATHYMETRIC DATASET INDEX: HOW TO DOWNLOAD THE CHS NONNA-100 BATHYMETRIC DATA:... 6 a) Download ZIP file and extract individual/multiple 32-bit GeoTIFF files... 6 b) Download ZIP file and extract individual/multiple XYZ files... 6 c) Export as a GeoTIFF using ESRI ArcGIS: INFORMATION REGARDING THE CHS NONNA-100 PRODUCT NAMING CONVENTION: DOWNLOADING THE METADATA FROM FGP DOWNLOADING THE METADATA FROM OPEN MAPS Page 1

2 1. BACKGROUND Using a Web Service allows users to visualize and share the non-navigational bathymetric data (CHS NONNA- 100) in a Read Only manner. Using an Image Service allow users to visualize, query and download the non-navigational bathymetric data (CHS NONNA-100) using ArcGIS. For non-arcgis users, a link has been provided to allow for the CHS NONNA-100 GeoTIFF files to be downloaded directly. The source data is stored on the Department of Fisheries and Oceans (DFO) network and published as a service to provide access both within the DFO network and to external partners. Any updates to the data are automatically reflected in the service as soon as it is (re-)published, thus minimizing the back-and-forth of sharing data and ensuring partners and users have access to the most up-to-date version. Below are the further details on how to access the CHS NONNA-100 Bathymetric data products. 2. HOW TO VIEW THE CHS NONNA-100 BATHYMETRIC DATA: a) View in the FGP Map Viewer: There are a couple of options for viewing the map in a Read only manner using the FGP Map Viewer. If you would like to view only this map, without overlaying other information, click on the View this map button. Page 2

3 If you would prefer to search FGP for multiple maps to overlay information, you can click on the Add to Map Cart button and then View map, where all maps that are in your cart will be displayed and overlaid in the FGP Map Viewer. b) View using the Web Map Service (WMS) connection in other applications: When you click on the WMS link, a URL will be provided that can be copied and used to connect to the Web Map Service (WMS) from other applications. Depending on the application, the individual pixels in the GeoTIFF can be queried. Page 3

4 The pixel value is the equivalent depth/elevation at that point. A negative value is a depth; a positive value is an elevation. The X, Y coordinates for the queried location may also be displayed for the queried location. Here is a screen capture using QGIS application, with the x marking the queried pixel. To the right the PixelValue is displayed ( metres); and below that the clicked coordinate X, Y. Page 4

5 3. CHS NONNA-100 BATHYMETRIC DATASET INDEX: To access an index of that shows the catalog of all available CHS NONNA-100 products, please download the KML file provided: When the KML file is opened in Google Earth, you can click on any of the cells/products and the CHS NONNA-100 Product ID will be displayed. This CHS NONNA 100 Product ID can be used to locate specific GeoTIFF and/or XYZ files for extraction from the ZIP files available on FGP and Open Data. Page 5

6 4. HOW TO DOWNLOAD THE CHS NONNA-100 BATHYMETRIC DATA: There are several ways to download the CHS NONNA-100 products, in 2 different formats (32-bit GeoTIFF and XYZ) a) Download ZIP file and extract individual/multiple 32-bit GeoTIFF files By clicking on the ZIP link you will have the option to open or save the.zip file which contains ALL of the individual CHS NONNA bit GeoTIFF files. These files can be extracted individually from the.zip file and can be opened in the Client s preferred application. Please note that downloading this.zip file may be time consuming. Once the ZIP file is downloaded, you can use the CHS NONNA-100 Bathymetric Dataset Index to locate specific datasets/products and extract only these. Alternatively, if only a few specific CHS NONNA-100 products are required, the TIF files can be accessed and downloaded via ArcGIS. b) Download ZIP file and extract individual/multiple XYZ files By clicking on the ZIP link you will have the option to open or save the.zip file which contains ALL of the individual CHS NONNA-100 XYZ files. These files can be extracted individually from the.zip file and can be opened in the Client s preferred application. Page 6

7 Please note that downloading this.zip file may be time consuming. Once the ZIP file is downloaded, you can use the CHS NONNA-100 Bathymetric Dataset Index to locate specific datasets/products and extract only these. c) Export as a GeoTIFF using ESRI ArcGIS: By clicking on the ESRI REST link users will be able to view the CHS NONNA-100 in: Clicking on the links for ArcGIS Online map viewer and Google Earth will open the data for viewing only in these applications. To QUERY and DOWNLOAD, you must use the ArcMap link to open in ArcGIS. Click on the ESRI REST link; Select ArcMap from the View In list; At the bottom of the webpage in the file download bar: o Select Open to automatically open the FGP_NONNA_100.lyr file with ArcGIS; or o Select Save to save the FGP_NONNA_100.lyr file to a specific location and open with ArcGIS. Once the data is open in ArcGIS there are several methods to change the display from a gray scale to show a rainbow variation for different depth ranges, if desired: Right click on the FGP\NONNA_100 layer in the Table of Contents window and select Properties. Select the Symbology tab. Under the Show menu, select Classified or Stretched, each will all the desired Color Ramp to be selected. Once the data is open in ArcGIS follow these steps to QUERY and DOWNLOAD: Right click on the FGP\NONNA_100 layer in the Table of Contents window and select Open Attribute Table. This will allow you to view the information about each CHS NONNA-100 product. Page 7

8 The Fields listed below will be visible. Please reference following link for a detailed description of each field - OBJECTID ( type: esrifieldtypeoid, alias: OBJECTID ) - Shape ( type: esrifieldtypegeometry, alias: Shape ) - Name ( type: esrifieldtypestring, alias: Name, length: 200 ) - MinPS ( type: esrifieldtypedouble, alias: MinPS ) - MaxPS ( type: esrifieldtypedouble, alias: MaxPS ) - LowPS ( type: esrifieldtypedouble, alias: LowPS ) - HighPS ( type: esrifieldtypedouble, alias: HighPS ) - Category ( type: esrifieldtypeinteger, alias: Category, Coded Values: [0: Unknown], [1: Primary], [2: Overview],...5 more... ) - Tag ( type: esrifieldtypestring, alias: Tag, length: 100 ) - GroupName ( type: esrifieldtypestring, alias: GroupName, length: 100 ) - ProductName ( type: esrifieldtypestring, alias: ProductName, length: 100 ) - CenterX ( type: esrifieldtypedouble, alias: CenterX ) - CenterY ( type: esrifieldtypedouble, alias: CenterY ) - ZOrder ( type: esrifieldtypeinteger, alias: ZOrder ) - Shape_Length ( type: esrifieldtypedouble, alias: Shape_Length ) - Shape_Area ( type: esrifieldtypedouble, alias: Shape_Area ) To interrogate the values within a product, select the Identify tool ( ) from the toolbar along the top of the ArcMap window. The Identify window will open and the cursor will change to an arrow with the identify symbol. Use the cursor to click on a raster pixel. The depth and location coordinates will be shown in the Identify window. Page 8

9 A CHS NONNA-100 product can be exported as a.tif which can be viewed and interrogated in other applications. Select the required CHS NONNA-100 product and right click on the layer in the Table of Contents to select Data Download Selected Rasters. In the Download Selected Rasters window you can select the target location to save the.tifs, and you can click to select/deselect the targeted rasters from the highlighted list. The raster export can be of the entire raster product or clipped to the data frame extent. Once all of the targeted files have been selected, click download. The.tif can then be opened in other applications where they can be viewed, selected and interrogated. Page 9

10 5. INFORMATION REGARDING THE CHS NONNA-100 PRODUCT NAMING CONVENTION: The naming convention of the products indicates the south-west corner of the product in the index. Example: CA2_3900N06300W CA = Canada 2 = internal to the Canadian Hydrographic Service 3900N06300W = south-west corner coordinates of the individual CHS NONNA-100 product 6. DOWNLOADING THE METADATA FROM FGP By clicking on the appropriate icon, the CHS NONNA-100 metadata can be downloaded to either XML format or PDF format. Page 10

11 7. DOWNLOADING THE METADATA FROM OPEN MAPS On the right-hand side of the record look for the section called About this Record. The metadata can be accessed in multiple formats. Page 11