Short term field measurements of aeolian transport, using a saltiphone
, indicate that actual rates of transport deviate considerably from th
e potential rates predicted by transport equations. When examined in d
etail, however, potential rates are approached during special conditio
ns: mostly when the wind blows offshore, parallel or slightly oblique
to the beach and relative humidity is below 85%. Also, the potential r
ates of transport may be approached when wind speeds considerably exce
ed threshold speed, even during showers. The main cause of the large d
eviation of actual from potential rates is in the absence of transport
during very wet conditions (prolonged rainfall) regardless of wind sp
eed, and the variation of threshold velocity with time. The threshold
velocity increases during wet conditions, with onshore winds or becaus
e of the presence of algae. Therefore, potential transport is defined
as the transport optimum. To predict the actual rates of transport acc
urately, insight into the variation of the threshold velocity is essen
tial. Aeolian transport of sand seems to be related to moderate events
and not to extreme events, conforming to the principle of magnitude a
nd frequency.