More ways to skin the cat: Google Fusion Tables.
The survey is leveraging the new Google Fusion Tables as a storehouse for the ever-increasing volume of GIS data being assembled for documenting the Carolina bays. Once the data has been loaded into these on-line tables, maps and graphs can be generated. Links can then be grabbed for these “Visualizations”, and the dynamic contents of the table can be presented in web pages, such as this one, which functions as a geospatial index to our original 250 fields of Carolina bays::
Fusion tables are available free to anyone who has a Google account. The facility is a bit like their spreadsheets, but specifically engineered for the visualization of data which has geographic content. Latitude and longitude are puled from the table entries you make and will geocode it for display on the virtual globe, as shown above. You can use supplied templates (or create your own custom html) to control the pop-up balloon contents. Those contents can easily display values, pictures, etc referenced from your table column entries for that geocode location.
We are using the visualizations as “indexes” into our Google Earth KML files, offering us a way to populate these web pages with examples. But more importantly, we are using extracts from the Fusion Table “Carolina Bay Geospatial Survey” to populate our Google Earth KML. Here is how we do that: Each octant has a specific number - for example, 141312 - and that number is included as a metadata element for each bay located within that octant. The full table can be queried for all bays with that octant number, using the format shown here:
This string is used as the address for a Google Earth network linked element 141312 bays, in DOM below. Expanding this in Google Earth, we see it is a “Fusiontables folder” containing bay placemarks. Clicking on the placemark brings up a popup with meta data for the bay, as contained in the Fusion Table. The format of the popup is html customized by us and entered into the Fusion Table map instance setup. The contents of this folder is dynamically loaded from the on-line table, allowing the local copy to be easily updated using the “refresh” menu item.
In addition, you can "visualize" the data in a few chart types. This “live” embedded chart shows the plot of my 250 bay "fields" as the data exists in real-time, showing how elevation above sea level graphs against the longitude. What it shows is that the bays are at increasing elevations as you move westward. No surprise, given the landscape of the US!
Perhaps the most powerful feature of Fusion Tables is the ability to not only share individual tables to others, but the option to allow for collaborative access to those tables, with several security options to control access and editing privileges. I hope to leverage this with collaborators who are helping to capture the bay metrics.
The table bellow shows the Bearing of bays on the East coast plotted against their latitude . This demonstrates the concept that “bearing is systematic by latitude”
Google Earth Community Forum Posts
The process followed in this discussion was documented in a series of posts to the Google Earth Community, hosted in the Earth and Geography (moderated) forum. A copy of the thread is included here for reference.
March 8, 2012 UPDATE: The Keyhole forum has been migrated into a Google Groups venue. The PDF links below display the topic as it was originally posted.
Download a PDF copy of Forum Posts Page 1
Download a PDF copy of Forum Posts Page 2
Download a PDF copy of Forum Posts Page 3
Download a PDF copy of Forum Posts Page 4
Download a PDF copy of Forum Posts Page 5
In addition, please reference the following additional posts to the forum:
Of Sand Dunes and Carolina Bays
Blythe Bay in Wilmington, NC
The mystery of the Carolina Bays
Link to learn about >>>
The Google Earth facility is a powerful GIS tool which is very "approachable" and intuitive to casual users. Google Earth (GE) can be obtained at GoogleEarth.com.
The identification of Saginaw ejecta and crater landforms can be accomplished easily using GE. Annotation of each location with structural characteristics and linking information are all easily accomplished. The resulting database can be managed as a structured medadata text file, which is easily distributed to other collaborative users. As we build the database of these elements, we will offer our viewers access to the "Keyhole Markup Language", or KML file. A zipped version , KMZ, of these files are also available. A benefit of the zipped file is that the relevant overlay images can be imbedded in the structure.
Our LiDAR overlay database is quite large, but the loading is very efficient since it is focused on the extend of the Earth shown in the viewer. The KML references internet connections to load the overlays from the Cintos.org site, so the controlling files are usually only 1 kb. We offer our collection of KML files on our KML Downloads page.