More on The Pittsburgh Chain Shift Described

The description of vowel variation in the Pittsburgh area was advanced considerably by the description of 13 residents of the city and the surrounding region in Labov et al. 2006, which describes a rotation of vowels in the lower central and back regions identified as the Pittsburgh Chain Shift (PCS). This shift is characterized by a merger of (o) and (oh), as in many dialect regions of the US to the west of Pittsburgh. However, in the Pittsburgh area the vowels merge higher and further back – on (oh) – than the more common merging on (o). This essentially backward movement of (o) leaves space open the central lower short vowel space, and becomes part of a chain shift as (ʌ) moves into this space: