Canadian Shift

The Canadian Shift is a chain shift of vowel sounds found primarily in Canadian English, but also possibly in some other dialects (for example, younger Pacific Northwest English). It was first described by Clarke, Elms and Youssef in 1995, based on impressionistic analysis. The shift is structurally identical to the movement of front vowels in the California Shift of California English; whether this a coincidence or not is not yet clear.

The shift involves the lowering of the tongue in the front lax vowels /æ/ (the short-a of trap), /ɛ/ (the short-e of dress), and /ɪ/ (the short-i of kit).

It is triggered by the cot–caught merger: /ɒ/ (as in cot) and /ɔ/ (as in caught) merge as [ɒ], a low back rounded vowel. As each space opens up, the next vowel along moves into it. Thus, the short a /æ/ retracts from a near-low front position to a low central position, with a quality similar to the vowel heard in Northern England [a]. The retraction of /æ/ was independently observed in Vancouver and is more advanced for Ontarians and women than for people from the Prairies or Atlantic Canada and men.

However, scholars disagree on the behaviour of /ɛ/ and /ɪ/:

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