We always get the question of whether it is clearer in the morning for snorkeling as opposed to the afternoon, is dependent on many variables. These variables can include, but not be limited to, weather conditions, bottom composition, suspended particulate in the water, water movement and even time of day. All of these will have some bearing with regard to visibility.BOTTOM COMPOSITION
For water clarity, bottom composition is a major component in determining ideal conditions. Bottom composition can include, but not be limited to, sand, silt, mud, rock, coral or vegetation. The best explanation as to how bottom composition can affect water clarity would be to compare a handful of gravel to a handful of fine dirt. If you were to throw each into the air you would notice that the gravel would settle a little quicker to the earth than the fine dirt. In an air environment, the time difference, might be measured in miniscule fractions of a second. In water the time difference is more noticeable because water is approximately 800 times denser (thicker) than air. Both the gravel and the finer dirt would settle slower than they did in an air environment but the time difference could now be measured in minutes rather than fractions of a second. The finer the sediment, the longer it takes to move through the liquid environment to the bottom. The heavier the sediment, the shorter the time it takes to reach the bottom. This being said, then any disturbance of the bottom composition will have some affect on visibility.
In order for you to cause any disturbance of the bottom composition, you would actually need to have to come into contact with the bottom. This contact would more likely occur in shallow water such as entering the water from a beach or shallow water. So, in a perfect world, as a snorkeler who does not come into contact with the bottom composition should expect excellent visibility. Right? The answer would be yes, but we dont live in a perfect world. The world that I live in, has other factors that can muck up the visibility. So not only think of your breathing but also the placement of your fins, it is important for your experience.TIME OF DAY
The time of day may have an affect on visibility with respect to light penetration and tides. The time of day when there is the most sunlight hitting the water would be mid-day when the sun is directly overhead. Tidal movement which is caused by the gravitational relationship of the sun and the moon on the earth. While the sun does have some affect on tidal movement, the moon has the most affect. The best time to go snorkeling from the shore with regard to visibility would be high slack tide. This is the time when the tide has ended and low tide begins. So the most ideal conditions to go snorkeling, expecting the best visibility would be a cloudless day at noon during high slack tide in an area with a rock bottom and totally devoid of algae. If that can't be found then settle for something close to that.WATER MOVEMENT
Whether it is waves gently lapping at the beach or waves crashing over a rocky shoreline, I think it is safe to say that water does move. The main cause for water movement is wind blowing across the surface of the water but there are a host of other factors that can affect the movement of the water. The movement of the water can also have an affect on the visibility. Rapid water movement can churn up the bottom sediment and depending, again on the weight of that sediment, keep it in a suspended state without really allowing it a chance to settle back down.SUNLIGHT
Sunlight (or lack of) can affect visibility in the water also. Sunlight entering the water can have an affect of how well you can see under the water. Snorkeling on a cloudy day is going to mean less light entering the water. Less light will also mean less color. This would be similar to being in a brightly lit room and having the lights dimmed to a lesser intensity. The colors that were seen when the light was bright will have become more muted in intensity.ALGAE BLOOMS
Algae is a plant-like organism that is found in both fresh and salt water. During unseasonably warm temperatures along with other factors which scientists are still studying, this algae flourish rather quickly and in great number. Algae blooms are relatively short lived in duration but can block sunlight by covering the surface of the water.WEATHER
Weather can have a major impact on visibility as well. Post hurricane water conditions may be less than desirable with respect to visibility. This would be largely due to the amount of types of particulate matter that were either stirred up from the storm or dropped into the water from the storm.
By Roy Jamason
Written Sept. 26, 2015