Why some beaches have bluer water than others
THERE are three things that make the perfect beach - good weather, golden sands and bright blue water.
But there is a reason some seasides have much bluer oceans than others.
The sea is not actually blue - the National Oceanic and Atmospheric Administration (NOAA) explains that most of the world's oceans are "completely dark".
They state: "Most of the ocean, however, is completely dark.
"Hardly any light penetrates deeper than 656ft, and no light penetrates deeper than 3,280ft.
"The ocean is blue because water absorbs colors in the red part of the light spectrum.
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"Like a filter, this leaves behind colors in the blue part of the light spectrum for us to see."
A bluer sea is caused by a number of factors.
One is the water being shallower, often found around islands such as Greece and Italy, as the light can permeate the water more.
Places like the Caribbean also have bluer waters as the islands have heavier sand sediment which makes the ocean seem less murky.
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Even plankton can change the colour of the sea.
According to NASA: "The basic principle behind the remote sensing of ocean color from space is this: the more phytoplankton in the water, the greener it is.
"The less phytoplankton, the bluer it is."
Other factors include calmer water, as the murkier water further down is less likely to be churned up to the top.
If you want blue water in the UK, you should head to the Isle of Mull - and you might even spot fluffy cows.
And here's the best hidden Spanish beach with bright blue seas but without the crowds.
