Import from Web: Difference between revisions

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=== Imagery ===
=== Imagery ===


All the imagery (World Imagery, Street Maps, Topo Maps, and OpenStreetMap.org data) are available for anywhere on the earth.  Besides downloading these images using the Import from Web command, these images can be read as online maps and then converted to a static map (stored locally on your computer) for faster display after you have decided on a project area.
Most of the imagery (World Imagery, Street Maps, Topo Maps, and OpenStreetMap.org data) are available for anywhere on the earth.  Some imagery, such as US Topo Maps, are only available for areas of the United States.  Besides downloading these images using the Import from Web command, these images can be read as online maps that change resolution dynamically depending on your location.


=== Land Cover Data ===
=== Land Cover Data ===

Revision as of 15:59, 6 September 2013

Overview

The Import from Web feature allows you to connect to the internet to download free data – images, elevation data etc. If you have an internet connection, this is an easy and convenient way to acquire this type of data.

The data is made available for free by various entities who provide web services. Each of the XMS programs has a number of available data types they can retrieve.

It should be noted that the Import from Web feature links to external internet sites which can change without warning. For example, historically the XMS programs retrieved data from the Terraserver site which was terminated. The termination or modification of an online source may result in invalid links in the XMS program until the links can be corrected.

The Import from Web command is accessed in a number of ways. These include:

  • From the "File" menu (WMS) or "Web" menu (SMS).
  • From the "Get Data From Map" macro (WMS only).
  • From the "Get Data" tool (SMS and WMS).

In the first two options the XMS program brings up a map locator tool (Virtual Earth) that allows the user to select (via pan and zoom) an area of interest and download data for this area. (As shown below)

The "Get Data" tool is available from the data toolbar when the XMS application is using a global projection. Which this tool active in SMS or WMS, the user can graphically select a rectangle in the graphics window and download data inside this rectangle.

Note: The Import from Web feature is no longer used for GMS as of GMS 9.0. The feature is still used in GMS 8.3 and earlier. However, since these tools used the now defunct "TerraServer" services, they are no longer referenced here.

SMS WMS

Data Availability

Elevation (NED, ASTER, and SRTM) Data

  • NED data contains the best available raster elevation data of the conterminous United States, Alaska, Hawaii, and territorial islands. NED data are not available for other areas.
  • ASTER and SRTM data are available for most of the earth's surface. The ASTER dataset is reliable and high-quality.

Imagery

Most of the imagery (World Imagery, Street Maps, Topo Maps, and OpenStreetMap.org data) are available for anywhere on the earth. Some imagery, such as US Topo Maps, are only available for areas of the United States. Besides downloading these images using the Import from Web command, these images can be read as online maps that change resolution dynamically depending on your location.

Land Cover Data

  • The 100 m Resolution CORINE dataset (raster) is available for anywhere in Europe.
  • The 30 m NLCD dataset (raster) is only available for the conterminous United States.
  • The Land Use Shapefile dataset is available for the entire United States.
  • The Global Land Cover dataset is available in 2 degree by 2 degree blocks for the entire world. The following steps were used to convert the Land Use data to a format that can be used for WMS hydrologic modeling:
  1. Go to the European Space Agency site to download land use data.
  2. Download the .zip file Globcover2009_V2.3_Global_.zip and unzip this file on your computer.
  3. Open GLOBCOVER_L4_200901_200912_V2.3.tif in a GIS (such as ArcMap) and convert it to an ESRI raster file. Trim the raster as needed, then convert the raster to a shapefile.
  4. Convert the file Globcover2009_Legend.xls to a *.dbf file and join this file with the shapefile values to get the land use names and IDs.

Soil Data

  • SSURGO soil datasets are available for all available SSURGO survey areas in the United States (as of August 2013).
  • A STATSGO soil dataset is available every state in the United States.
  • Data from the Harmonized World Soil Database are available in 2 degree by 2 degree blocks for the entire world. The WMS developers used the following steps to convert the soil data to a format that can be used for WMS hydrologic modeling:
  1. Download and install the Harmonized World Soil Database program to your computer from the Harmonized World Soil Database web site.
  2. Launch the HWSD Viewer on your computer. The soil data will be copied to the folder c:\program files (x86)\HWSD_v<xxx>\Data where <xxx> is the version of the viewer you have downloaded. The program may also be installed in c:\program files\<...> if you are running a 32-bit version of Windows. The following files are contained in this folder:
    1. The HWSD Raster *.zip file.
    2. The HWSD DBF file.
    3. The HWSD_META DBF file.
  3. Copy the files in the data folder to a writable location on your computer and unzip the HWSD Raster *.zip file.
  4. Open the .bil file in ArcMap and convert the *.bil file to a shapefile using the IDs.
  5. Join the HWSD DBF file with the IDs in the shapefile.
  6. Join the attribute IDs with the HWSD_META DBF file. This gives you a shapefile with the soil IDs and various soil attributes that can be used for hydrologic modeling in WMS.

Additional Information

Note that more vector-based soil and land use datasets are available; Contact Aquaveo if you are interested in adding data from a specific area to the list of available land use or soil data that can be downloaded. A comprehensive list of soil and land use data available for download is located here.

Terraserver images are no longer available because this web service has gone offline.

Using the Import from Web Command

When the Import from web command is invoked from a menu or macro, the virtual earth map locator is launched:


  • Virtual Earth Map Locator:Use the map in this dialog to go to your location of interest.
    • You can zoom in or out using the controls or the mouse wheel.
    • You can pan using the controls or by clicking and dragging. You can also enter the latitude and longitude to jump to a specific location.
    • Use the Map Options menu to turn on the floating controls in the map (search, pan and zoom).
    • Use the Map Style menu, or the floating controls, to change the map between Road, Aerial, and Hybrid.
    Virtual Earth Map Locator

Once the region for data download is defined, a series of dialogs appear which allow the user to define the data to be downloaded. These dialogs include:

  1. Data Service Options
    Here you select which type of data you are interested in.
  2. Save
    Now you are asked where you want to save the data. You only need to specify one file name, even if you've selected more than one type of data in the previous dialog. The files will all be given the same prefix but different suffixes.
  3. Confirm File Creation
    You may be asked to confirm that you want to create the files.
  4. Initialize Connection
    The following dialog is shown while the connection is being made.
  5. Select Scale
    Smaller numbers (larger scales) will result in better resolution, but longer download times.
  6. Downloading
    This dialog reports the download progress. If you click Abort, your image will exist but will be only that portion that you've downloaded so far.

Steps will repeat for each data type selected. After everything is finished, the data (images etc.) will appear in the Project Explorer.

See also