The neck of the rip is the channel in the sandbar which is eroded by the rip current. This is the main part of the rip. The neck can be wide or narrow, deep or shallow. The neck can be perpendicular (fig 1 I-type) on the bar direction, or under an angle or a combination (fig 2 Z-type and fig. 3 S-type). In the neck holes in the bottom can exist. After a storm the neck can be disappeared.
Often after a storm the neck will be shallow. The rip current will deepen out the channel and the rip is forming again. Strong wind-driven longshore currents will cause that the neck will be set under angle with the sandbar, see fig 2 and 3. However often the rip will be shallow than. The effect of this is that waves will break over there. For this reason it is difficult to recognise a rip channel of this type. That’s why the spotting of a feeder current is so important. If you see the feeder current you can estimate where the neck must be.
Sometimes the neck is very wide. It looks like a part of the sandbar is missing. The rip current will than be at the side of the neck.
In case of a wind driven current the rip currents will slowdown at narrow rips. At wider rips however they can move to the middle of the neck and remain persistence.
In a shallow neck there will be breaking waves in the neck. This will slow down the rip-current in the neck. However waves are not all even high and a group of waves can cause rip current fluctuations. Also breaking waves in the neck can cause undertow. The shape of the water will be very turbulent.
The next slide show is another attempt to show some rip pictures, in this case the neck of the rip. The red arrows point to the neck of the rip.
Go on now to the next section: the head of the rip.