Predicting Weather By The Moon - Xavier University Libraries

Weather By The Moon
Q’s and A’s
Q:I take it the term ‘stretched’ refers to the atmosphere’s
height, as if we were talking of the thickness of the skin of an
apple or an orange - not its molecular density But isn’t height
the same as pressure?.
A: The idea of thicker is indeed molecular density. A gas is
different to a solid. If a solid is stretched it’s thinner, but a gas
streched gets away from thickness issues because the faster
molecular movement tends to redistribute and equalise. Gravity
only acts on mass. On the far side of the Earth the area holding
the atmophere is still a closed container - its limits are set by
Earth’s gravity. So when the height of the air is lower, the air still
expands to fill the space, which is why pressure remains the same
whatever the height. I don’t think ‘thickness’ is a good word for a
gas.
Q: Why should a topdresser airplane be more careful than an
airliner about where and when during the course of the day it
flies?
A: Topdressing planes use propellers and airliners don’t. The jet
would not be subject to atmospheric stretching because all that
makes the jet go forward is the opposite reaction of the jet-thrust
moving backward
Q: If you use the phrase ‘atmospheric tides’, your reader
should get a clear idea of the similarities and differences
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