Use databases that index geographical, geological and environmental literature.
Here are a few suggestions:

• GeoBase

(1980 to present, 1.1 million journal articles, books, maps, government reports, conference proceedings - emphasis on geography and environment)

• GeoRefS

(1785 to present, 2.3 million journal articles, books, maps, government reports, conference proceedings - emphasis on geology, geophysics, hydrology, geochemistry)

• Web of Science

(1976 to present, articles in 8,000 scholarly journals - allows searching by keywords and by citations in the article)

• ScienceDirect

(1995 to present, 1,500 science journals from publisher Elsevier)

• JSTOR

(historical archive of older journals online)

• Scholars Portal Search

(multi-search engine that can search 60 databases at once)

For other databases available, see McMaster University Library.