Are you wondering why Caribbean water is so blue?
There are a few different factors that contribute, which I’ll share in this article.
Let’s start with a brief answer, in case you’re in a hurry…
Why is the Caribbean water so blue?
The main reason why ocean water is blue is because of the absorption and scattering of light, similarly to why the sky is blue. However, there are several other factors why the Caribbean is that (lighter) blue. The shallow depths, light-colored sand and small amount of phytoplankton are also factors.
1. Shallow Depths
Most of the Caribbean has that turquoise blue color because of the shallow depths.
The deeper the ocean, the deeper the shade of blue because the sunlight can’t reach the bottom.
When the water is deeper, it absorbs all the sun rays, creating a darker shade.
So the more shallow the water, the lighter the blue.
2. Light-Colored Sand & Coral
When the sun hits the bottom, the light-colored sand & coral become another factor in turning the Caribbean that light turquoise shade.
The sun reflects off these elements, causing a lighter blue to appear.
The lighter the sand & coral, then the lighter the shade of blue.
3. Small amount of Phytoplankton
Phytoplankton is a small microscopic single-celled plant that contains a green pigment called chlorophyll.
This is the same pigment that plants contain to capture energy for photosynthesis.
Even though these organisms are microscopic, they still have a big factor to do with the shade of color, especially when they’re in large numbers.
They reflect green, causing the ocean to turn a greener color.
So, because there is a smaller amount of them in the Caribbean, the ocean is clearer and bluer.
4. Resuspension of sand
You’ve probably noticed that where the waves crash, the water clarity is a bit foggier than other areas. That’s because of the resuspension of the sand.
When the waves crash and reform, it sucks up the sand, creating a foggier watercolor.
And the Caribbean sea tends to be calmer, which makes the water clearer.
Different areas in the Caribbean have slightly different watercolor due to the area’s currents.
There can be currents that suck a good amount of organisms into shallow depths, which can be a factor.
As stated above, when there’s more phytoplankton, the water turns greener.
And there you have it…
All of these factors combined are the reason why the Caribbean water is so blue.
The clarity and color of the Caribbean is a large part of why tourists keep returning, year after year.
Here’s a simple visual to show you.
References: Ocean Color by Nasa Science