The transfer of energy means, in convention process, transport of matter. In this case, hot water has lower density than cool water. The water with less density ascends and leaves gaps that are occupied with cooler water "packages".
Johann Strauss II
hope this helps
-- If acceleration and velocity are in the same direction,
then the object is speeding up.
-- If acceleration and velocity are in opposite directions,
then the object is slowing down.
-- If acceleration is perpendicular to velocity, then the object
is moving on a circular curve at constant speed.
Nitrogen and carbon dioxide