tr/J/L/;
[download]

  for(@$arrayref){
## I might be wrong but this loop is unnecessary,
## you are testing for a single key, a hash only has
## one instance of a given key.
#     while (my ($key, $value) = each %{$_}) {
#       print "$value\n"
#       if $key eq 'place';
#     }
#lookee --v
     print "$_->{place}\n" if exists($_->{place})'
#lookee --^
     while (my ($key, $value) = each %{$_}) {
       print "  $key = $value\n"
       unless ($key eq 'celcius' or $key eq 'place');
     }
   }
[download]

UPDATE: Added pointers to the new code, it kind of gets lost underneath all the comments.

--
perl -pe "s/\b;([st])/'\1/mg"