"Is published in association with a growing international network of information centers monitoring over 5,000 serial publications, books, reports, conference proceedings, translations and limited distributions literature."
The JCR Science Edition contains data from over 7,300 journals in science and technology for the year 2010 ONLY. All of the data that you see for journals and subject categories come from journal data published in 2010. If you search for a particular journal, you will see the 2010 data for that journal, including -- The number of articles published in the journal in 2010, the number of citations to that journal from articles published in 2010, and the Impact Factor calculated from 2010 data, and so on.
"Focuses exclusively on worldwide technical literature pertaining to the marine and brackish-water environment. It is totally comprehensive in its coverage of living and non-living resources, meteorology and geology, plus environmental, technological, and legislative topics."
Web of Science, formerly known as Science Citation Index, traces the references at the end of each paper published in a broad collection of 8000 journals in science and engineering. Use this database most efficiently to discover who has cited a paper written in the past.
This is a library tutorial on understanding citations found in searches of online databases and bibliographies.