Abstract:
The moisture and temperature structure of the trade-wind
mixed layer are compared under conditions of strong versus weak
trade. The data used are two series of aircraft psychrograph
soundings made over the ocean near Puerto Rico in early spring.
The first in conditions of strong undisturbed trade and high zonal
index (April 10 - 28, 1946) and the second under conditions of
weak rather disturbed trade and low zonal index (March 18 - April 7,
1953).
The weak trade soundings show a less homogeneous moisture
distribution and a less stable temperature lapse rate. Considerable
variation in structure of the lowest air accompanies changes
in the trade regime which may give rise to significant fluctuations
in energy input at the source region for atmospheric circulations.
The importance of wind stirring in the upward transfer of moisture
is indicated, which may affect the formation of trade cumulus clouds.
Further studies investigating the relation between air and ocean
structure at their boundary are suggested by the evidence herein,
which may relate to the formation of tropical storms.
