In
the rural subset of U.S. stations, the recent warm temperatures aren't actually that unusual, and it seems that it was at least as warm in the 1930s.
Not exact matches
Tieken, Marietta, and Marcell say
rural education is still a small
subset of the education world although they feel supported in their work at Harvard.
If you have an airport - only
subset, then you need neighboring
rural airports, which seems a little restricting.
The next step is probably to look at the
subset of
rural CRN12 stations.