Why Most Waters in Greece Are So Strikingly Turquoise
Why Most Waters in Greece Are So Strikingly Turquoise
If you’ve ever been captivated by the brilliant turquoise waters of Greece, the Caribbean, or the South Pacific, you’re not alone. These stunning shades of blue almost seem unreal—but there’s real science behind them.
So, what actually gives ocean water its color?
According to NASA, it all comes down to how light behaves in water. “The reason the ocean is blue is due to the absorption and scattering of light,” they explain. Water absorbs colors in the red part of the light spectrum very efficiently and lets blue wavelengths scatter, which is why we perceive the ocean as blue. While scattering plays a role, just like it does in making the sky appear blue, it’s absorption that dominates in clear ocean water.
However, as the National Oceanic and Atmospheric Administration (NOAA) points out, most of the world’s oceans are far from the shimmering blue we see in travel ads. In fact, below about 730 feet (220 meters), the ocean is almost completely dark. Go deeper than 3,600 feet (1,100 meters), and there is no light at all.
So what makes places like Greece, the Maldives, and Bora Bora look so dramatically different?
Greece’s turquoise waters: Light sand, and low plankton
It turns out, the brilliant turquoise hues in these regions aren’t just about sunlight—they’re also about what’s not in the water.
As explained by the Oceanic Research Group, shallower waters, especially around islands, tend to contain far fewer plankton and suspended particles. Plankton, while vital to marine ecosystems, can give water a greenish tint due to the chlorophyll they contain. When waters are relatively free of plankton, more sunlight penetrates and reflects off the seafloor, enhancing that bright blue appearance.
Another factor is the type of sand and sediment on the seafloor. In places like Greece, the sand is often white or light-colored and composed of heavier particles that settle quickly. Because there’s little disturbance from wave action or currents, the water remains crystal-clear, allowing the light to reflect more intensely.
Also, the calmness of these waters plays a key role. Tropical and Mediterranean regions tend to experience fewer upwellings—events where deep, nutrient-rich waters rise to the surface. According to NOAA, while upwelling is essential for marine life, it brings organic material that increases biological activity, which in turn darkens the water.
In contrast, the still, sun-drenched waters of the Greek islands remain undisturbed, allowing light to interact with the shallow seabed and create those mesmerizing hues that draw visitors from around the world.
Related: A Greek Vacation Dilemma: The Ionian Islands or the Cyclades?