Predicting Weather By The Moon - Xavier University Libraries

Weather Maps
respectively the American and South East Asian name for a
tropical cyclone. They form and travel over oceans and degenerate
to depressions when they reach land. Cyclones
develop mainly when the seas reach a temperature of about
28degC and this usually occurs when the Sun is over a particular
hemisphere and close to or past its solstice position
of that tropic, which will allow sufficient time for the
sun’s rays to heat the sea to that critical temperature.
The reason there are no cyclones off Brazil is probably
due to the very large volume of cold fresh water from
the Amazon that keeps the temperature of the adjacent
oceans below that required for a cyclone to form. Where
conditions are warm enough for them to form, the heating
process will continue after the Moon has crossed the equator
and into the other hemisphere.
The build-up of heat will be speeded to that level during
a Full Moon phase and into the Last Quarter because
that is the time for the low atmospheric tide, both from the
Moon being a night moon and because the Moon is over
the opposite hemisphere. Also, if the Moon is at perigee,
the atmospheric tide will be even lower because of the
greater gravitation effect from the Moon in that period.
Occasionally the New Moon will cause a tropical cyclone
to form, mainly due to the increased gravitational pull occurring
and especially if the Moon is at or near to crossing
the equator at this time.
The worst cyclone of last century hit Bangladesh on
November 13, 1970. The Full Moon was on the 14 th , and
the Moon was in Perigee on the 11th, 3 days before. The
destruction was widespread with an estimated up to a mil-
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