>I get most of my news on NPR.  For the last few days I have been
>hearing stories about Hurricane Aaron, until I read in today's paper
>that the name is Erin.

>My question: Who pronounces, as I do, Aaron and Erin differently?
Quite a few people in the US, mostly in the New England-New York axis, and quite a few others as well. NPR, of course, stands for "National Public Radio", an American institution, and Hurricanes Erin and Aaron (I've always thought it should be AAron, myself) are unlikely to be features of Somerset life, so we're talking about American English. Which I also speak.

There are a lot of reasons why there are homonymic names; in this case, AAron is originally Hebrew while Erin is Irish -- but both are suitably anglicized in any event. Hebrew and Irish have different vowel systems, and the anglicization of these two names seems to have proceeded independently of each other, so they haven't had the competition needed to keep the pronunciation separate.

Another reason (there's almost never just one) is that English dialects vary in which vowels they pronounce, and especially how they pronounce vowels around /r/, which is a retroflex central semivowel (a sort of "uh" with the tip of the tongue curled back) when it follows a syllabic vowel in many American dialects, including "General American" (Big Ten, NBC). In British RP (Oxbridge, BBC) and NE US accents (Harvard, WNBC) postvocalic /r/ is a normal shwa (/aw@ fey@ sIti/ 'Our Fair City'), without the retroflexed tongue, which apparently permits more distinctions to be made.

There are at least 11 phonemically distinct vowels in standard American English. The chart below indicates the ones in my own idiolect.

General (American)
               Front            Mid         Back
           +----------------+---------+-----------------+
       High| i   bead       |         |      u boo'ed   |
           |  I   bid       |         |     U book      |
           +----------------+---------+-----------------+
       Mid |   e   bait     |    @    |    o   boat     |
           |    E   bet     |   but   |   O   bought    |
           +----------------+---------+-----------------+
       Low |     ae  bat    |         |  a   pot        |
           +----------------+---------+-----------------+
But the chart above is collapsed into a different number before /r/. Most English vowel phonemes neutralize some distinctions there. The chart below indicates this neutralization (again, in my own idiolect).
Before /r/ (American)
               Front            Mid         Back
           +----------------+---------+-----------------+
       High| I   mere       |         |      U   moor   |
           +----------------+---------+-----------------+
       Mid | * e   Mary     |    @    |    O   more     |
           | *  E   merry   |  myrrh  |                 |
           +----------------+---------+-----------------+
       Low | *   ae  marry  |         |  a   mar        |
           +----------------+---------+-----------------+
As can be seen, before /r/ the tense/lax distinction in English loses its force (this is called neutralization in the trade). What's especially interesting is that the starred (*) vowels above are distinguished by some American dialects and not by others.

Where I grew up (in DeKalb, IL, 100 km W of Chicago) Mary, merry, and marry all had the same vowel, an open lax /E/. I have since learned that residents of certain parts of the American Northeast pronounce them separately.

To paraphrase Matthew Rabuzzi, think lobally, yack locally.
We really have no choice in any event.

  - John Lawler       Linguistics Department and Residential College     University of Michigan
    "Language is the most  massive  and  inclusive  art  we know,  a           - Edward Sapir
      mountainous and anonymous work of unconscious generations."       Language (1921)
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