The following series deals with the five prominent human senses as they apply to safe boating and correct navigation. Hearing, Sight, Touch, Awareness, and Balance.
Let’s begin with Hearing. Imagine if your ability to see with unrestricted visibility on the water was quickly reduced to almost nothing. You have probably experienced this similar weather situation driving your vehicle on the roadway and it can be a very disturbing event sometimes. When it comes to boating operations, it is best served safely and that includes confidently maneuvering in adverse conditions. If you go out on the water, for whatever reason, you will someday most likely encounter this scenario of low visibility. It comes in a wide variety of forms; fog, rain, snow, smoke, day or night, and various combinations of all the factors. This dangerous encounter doesn't have to be the end of your voyage, but it does absolutely require you to engage other senses, especially hearing, to navigate safely through the risky situation. The proficient use of advanced electronics such as Radar, GPS, and FLIR can be of great value if operated effectively with the information received by the observer correctly interpreted. There is no room for error, everything is at stake, the final decisions to be made expressly by you, the person in charge of piloting the vessel. How’s that for pressure?
Something remarkable happens almost immediately as the ability to see begins to diminish. Unlike a road surface where you can feel a subtle change in your movement by the tires as the vibration reflects off the surface of the pavement. Even a sense of direction of your vehicle is discernable within close proximity and markings on the traffic lanes. On the water, those sensory impressions do not exist. The audible input of hearing sound now takes an even more profound importance to your journey. By proper listening methods, you can calculate approximately whether the object is close by, approaching, crossing, passing, and even moving safely away from your position. It is called Doppler Effect; https://en.wikipedia.org/wiki/Doppler_effect. This boating safety capability does take some practice and it is very achievable with time and experience.
How would you practice something of this nature and complexity? The next time you’re underway or at the mooring, in any condition of visibility, safely close or cover your eyes. If the unwanted noise level on your vessel is low enough, you can begin to experience the expanded faculty of hearing and how it is described in the Doppler Effect. If the sound increases then the object is moving towards you, lowering of the audible signal shows divergence. Ascertaining lateral movement by sound, to the right or left demonstrates bearing drift meaning the object will most likely pass your position without incident, although risk is always present until it is well past and clear.
If you should ever find yourself in this predicament while underway, immediately slow down, affix your navigational position marking with a way-point on your Multi-Function Display if you have one and intently listen to what is going on around the vessel. You'll be amazed at how keen your sense of hearing becomes in times like this. Sound travels in a distinct pattern that is very recognizable with practice. Also let other nearby boats know your location with proper sound signals as listed in the Navigation Rules of the Road. It all comes down to this;