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Statistics (2013/02/18)
Pages: 3157
Users: 6493 (4 active)
Properties: 218
Categories: 59
Templates: 65
Forms: 38
Table of Contents

Tethys is a public environmental impacts knowledge management system created by Pacific Northwest National Laboratory in support of the U.S. Department of Energy Wind Program and Water Power Program. The primary function of Tethys is to facilitate the creation, annotation, and exchange of information on the environmental effects of Marine and Hydrokinetic (MHK) and Offshore Wind (OSW) technology.

Content Overview[edit]

As industry, academia, and government seek to develop new renewable energy sources from moving water and offshore wind, potential environmental effects must be evaluated and measured to ensure that aquatic and avian animals, habitats, and ecosystem functions are not adversely affected, nor that important coastal and ocean uses are displaced. Severe weather in a complex system has created many hurdles that prevent developers from launching project arrays at this stage, but reports and analyses are being completed as to how these devices may affect the environment. While these studies are scattered among different organizations, Tethys is attempting to create a centralized hub where this information can be found.

Each document is labeled with an environmental "stressor" and "receptor", which categorize the type of potential harm and the affected area of the environment. The categories and the technology types covered are listed below:

Stressors Receptors Technology Type
Tethys Knowledge Base

Knowledge Base[edit]

The knowledge base is primarily displayed as a table view that utilizes the alphabetical column sorting, facet box selection, and keyword search to allow users to easily sift through the information. Present is a total of 1010 relevant media entries, consisting of journal articles, technical reports, websites, conference papers, presentations, workshop articles, theses, book sections, videos, datasets, magazine articles, project site information, and research study information. Due to a large quantity of data slowing down load times, the process was expedited by adding a function where only fifty media loads at a time until the user scrolls to the bottom of the page. This is a growing database, where relevant materials that are newly published or discovered will be added.

Tethys Map Viewer

Map Viewer[edit]

In an effort to capture the current status of marine hydrokinetic energy projects in the United States, Tethys partnered with the Federal Energy Regulatory Commission to create a clean interactive map showing the locations of preliminary permits. Selecting one of the sites will reveal a specific page with some general information and a link of a list of all documents related to the project. Any media from the knowledge base that has an associated geotagged location will also show up as a distinguishable bubble on the map. Internationally, project sites and research studies were gathered through a project known as Annex IV. Users may interact with the map with zooming and panning functions, facet box selection, and a keyword search. There are currently 385 media present on this map.

Annex IV[edit]

Annex IV is a collaborative project among member nations of the IEA Ocean Energy Systems (OES) to examine environmental effects of ocean energy devices and projects. There is currently a wide range of ocean energy technologies and devices around the world; the few data that exist on environmental effects of these technologies are dispersed amongst different counties and developers. This international effort has compiled data on projects worldwide, which has been housed with all the Tethys information. It is always noted whether data was collected for Tethys or Annex IV.

Technical Overview[edit]

This site was constructed with SMW in mind from the very beginning, by a team familiar with Semantic MediaWiki. While the structure of the information evolved a bit over time, the basic information structure remains largely intact with mainly additional properties used to capture new details that emerged as the site grew over time.


The MHK site uses components from the Knowledge Encapsulation Framework (‘’’KEF’’’) which combines a ‘’’Semantic MediaWiki’’’ with varying combinations of Drupal, Wordpress, and the PHPBB Forum to create a customizable suite of intertwined tools offering a repository for information, a podium for group announcements, and an area to discuss different division topics. In this case making use of Drupal to act as both a blog for related announcements, and as an integrated forum used inline on various wiki pages.


Two main foci of the site, the Knowledge Base and the Map Viewer, are powered by what we have dubbed SolrExhibit. A portmanteau of Apache’s Solr and MIT’s SIMILE Exhibit. SolrExhibit uses the excellent Exhibit front-end, powered by the blazingly fast Solr back-end.

One of the problems with Exhibit is that it loads all of the data into the browser, and then organizes it to provide search and faceting capabilities. Its strength, of course, is in the user experience. With maps, tiles, tables and timelines filtered by facets and text search, it is very flexible and natural to use. Solr, which is based on the Lucene text search engine, with the added ability to provide facet counts and a plethora of other options, was a natural fit as the back-end for Exhibit.

We created a Semantic MediaWiki extension that modifies the Solr index when properties are updated. Properties are associated with their pages in Solr as key-value pairs. We also created an extension that allows for the specification of Exhibit pages in the wikitext. When one of these pages is loaded, our modified Exhibit code is loaded in the browser. This code queries Solr for data based on the initial conditions in the wiki, and whenever the user makes selections or types a query. Solr responds with just the content that is visible on the web page, including facet counts. This is very, very fast. That makes our users very, very happy.


The site makes use of a customized skin with custom page level features to help define a hierarchy structure on the site. Pages are created and edited mainly via the use of semantic forms, with some custom features injected via a hook upon form submission to help relate published documents with their respective project sites. Heavy use of the maps extensions is made to help display both document and project locations from around the world, and the widgets extension is used to allow the inclusion of inline video on several of the wiki pages. Other extensions in use on the MHK site include Semantic Forms, Semantic Internal Objects, Semantic Maps, Semantic Result Formats, SMWHalo, Parser hooks, Drupal Forum Integration, Maps, ParserFunctions, ScriptManager, SimpleFeed, TreeAndMenu, URL Arguments, Variables, Widgets, ARCLibrary, PNNL Modules, and the Validator extension.

Future Plans[edit]

  1. Developers have laid the foundation for a blog that will report on current work being done in the marine hydrokinetic and offshore wind fields.
  2. Research to capture useful international connections is being compiled to help connect the industry.
  3. Reviewers in professionally relevant fields will provide input with site suggestions in terms of additional content and functions.