Terry,

So what do you
call the number you dial up to make the altimeter read airport
elevation?


altimeter setting. It is given in inches Hg, too, with 29.92 being
equivalent to 1013 hectoPascal. The Brits use another non-SI unit,
namely millibars, which is the same as hectoPasal.

--
Thomas Borchert (EDDH)