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Climate Change: Oceans to Atmosphere (EES2096)

Recommended library and other research resources for EES2096

Generating Keywords

The first step in creating a viable search strategy is to brainstorm a set of keywords. 

Keywords are the core components of your search strategy. You will put them together into search terms using Boolean operators (see below) and enter them into databases or other information sources. In order to brainstorm keywords, write out a research question, i.e., one of the questions you will be answering with the information you discover. Identify the key terms within that question: what is it exactly you are looking for information about? Start listing off all the examples and synonyms you can think for those key terms. These are the keywords you will be trying out as you formulate your search strategy.


Thesauri & Controlled Vocabularies

Once you have created a set of keywords and chosen a database (see the "information sources" tab), the next step is to explore the database's thesaurus and/or controlled vocabulary. 

A controlled vocabulary is the language of the database. It consists of the various terms assigned to the article (or book chapter, etc.) by indexers. The database's search engine uses these terms to produce results for a query. You can think of controlled vocabulary terms as being like online hashtags. When you see a term with # in front of it on social media, you know that term is a central topic for the post in question. The same applies for terms in a controlled vocabulary--they have been deemed important for explaining what the article (or book chapter, etc.) is all about.

A thesaurus fleshes out the controlled vocabulary by explaining hierarchical relationships among search terms and offering alternatives to common search terms which are not listed in the vocabulary.

By exploring the controlled vocabulary and/or thesaurus in a given database, you can learn which search terms are likely to produce relevant results. Every database works differently in terms of its controlled vocabulary and how that vocabulary translates into search terms. The best method is trial-and-error; try out different sets of terms and see what kind of results you get! As always, if you have any questions or concerns, you can make an appointment with your librarian. 

Boolean Operators

This image uses venn diagrams to explain boolean operators.

Once you've brainstormed some keywords and translated them into search terms with the help of a thesaurus and/or controlled vocabulary, your next step is to combine these search terms into a viable query. You can do so with Boolean operators. 

Link search terms together with the three operators: AND, OR, NOT. Use AND when you want to retrieve results that include all of the search terms. Use OR when you want to retrieve results that include any of the search terms. Use NOT when you want to exclude a certain term from results.

Truncations & Wildcards

One issue you may encounter while executing your search strategy is that there are different forms of the words you're using. Maybe there's a plural form, maybe your term is a root word for a longer word, etc. If you only use one form as a search term, you run the risk of excluding relevant results that use a different form. In order to make sure that your query retrieves all the relevant results, use truncations & wildcards to capture all the forms of a word. 

  • Use * for multiple characters (plural forms and suffixes)​

  • Use ? for single characters​

  • Use $ to replace zero or one character (odo$r = odor + odour)


After you have used your search terms in conjunction with Boolean operators and truncations/wildcards to create a query, the next step is using filters to reduce the result set to a manageable number.

Different databases will have different filters available. As with keywords, your best method is trial-and-error; use different filters and see how effective they are at reducing your result set. Here are some widely available filters and how best to use them:

Publication Date/Date Range - use to focus on the most recent results or results within a given time period (for example, if you're looking for information about your community in past decades). 

Document Type - use to reduce result set to research articles, government documents, etc. depending on the kind of information you're looking for. This filter can also often be used to exclude certain document types--for example, if you want to exclude news articles so you can focus on scholarly research articles. 

Subject/Topic - use to narrow down your result set to focus on your specific topic. As with "document type," this is often most useful in terms of exclusion. 

Location/Region - use to narrow down your result set to articles relevant to your community.

Language - use to exclude languages other than English (unless other languages are relevant to your community). 

Age/Gender - use to narrow your result set to the demographics relevant to your community.