Great for overviews and background information, the following collections of online encyclopedias, dictionaries and other reference sources are available through the SSU library. The content of these databases can be accessed and read online. Search many titles at once or each individually.
Full text of the McGraw-Hill Encyclopedia of Science & Technology, with thousands of illustrations, animations, images and the latest headlines, biographies, and more.
Check out the fascinating books that come up with searches like the following:
arctic and environment* 
Use the * to find:
environment
environmental
environmentalist, etc.
Geographic information systems 
finds more relevant information than just GIS.
Climat* change*
will bring up: 
climate change
climate changes
climatic changes, etc.