Why Do White Sand Beaches Stay Cool?

With sand as white as snow, Siesta Beach on Siesta Key is consistently named one of the best beaches in the United States.

Aside from its sheer beauty, this powdery sand has a few other benefits. First of all, it packs well, making it perfect for sandcastle-building, beach volleyball, and jogging.

Secondly, it never gets hot enough to burn the bottom of your feet on the way back to your Siesta Key vacation condo. Most of us know that experience walking on darker colored sand on a hot day, it can be quite uncomfortable and make beach shoes a necessity.

This cool beach sand is not unique to Siesta Key, but it is relatively rare further north in the U.S. You might know how to enjoy it, but many still wonder where the white sand of Siesta Key comes from and how it stays so cool.

So, why does the sand in the Gulf of Mexico stay cool?

The Science of Sand

Geology can help us find the answer.

Most beaches are made up of mixed materials – sand, gravel, pebbles, rock, coral, and seashells – and are constantly changing in composition. Material accumulates and erodes over the course of a beach’s life, never settling for long. This is what gives beaches their different colors.

Beaches come in a variety of shades and colors: white, black, tan, yellow, and red, among others. The majority of beaches fall into the neutral, beige tones, like tan and yellow, because they’re made up of a wide assortment of materials.

However, some beaches are uniform in their composition. Volcanic activity on the coastlines of Hawaii, Iceland, and New Zealand, for example, has created black beaches from the dark-colored debris that erupted.

If black beaches are volcanic rock, then what are white sand beaches? In contrast to other beaches of the world, the sand on Siesta Key is pure white. That’s because the sand here is made up of 99 percent pure quartz, giving our beach not only its color, but its powdered sugar feel.

The beaches of Siesta Key have quartz that originally came from the southern Appalachian Mountains via rivers to the Gulf of Mexico, washing up on the beach over time. Ultimately, this created beautiful Siesta Beach, a truly rare and unique beach destination that has this large, natural quartz accumulation.

Now that we’ve answered the question, “why do some beaches have white sand,” we can move on to one that affects our day-to-day life while on vacation. Why do white sand beaches stay cool?

Cool Beach Sand

The answer is simple: the color reflects the sun, as opposed to absorbing it. This works the same way with clothing. If you wear a black t-shirt on a sunny day, you’ll almost certainly sweat more quickly than if you wear a white one. This is because light is absorbed by dark colors, and reflected by light ones.

Another reason the beaches of Siesta Key stay cool is that its primary ingredient, quartz, is a type of crystal. Crystals are conductors that serve to disperse heat, which is why they are used to prevent overheating in cellphones and computers. This helps to explain why the sand in Southwest Florida isn’t hot.

Siesta Key’s beaches aren’t all the same. If you head to Turtle Beach in the south, the same is a little coarser, and a little less snow-like. This is because the beach is made up of a trail mix of ingredients, as opposed to just one.

If you haven’t visited Siesta Key, there’s simply nothing quite like the luxurious white sand here, and that alone makes a trip worthwhile, along with the many unique things to do and attractions you’ll find – from top rated restaurants, to scenic parks, fishing charters, kayaking, snorkeling dolphin tours, local events and much more.

Visit our barrier island for the activities, sun, and of course the beautiful, sandy beaches that line its shores. With a number of Siesta Key monthly condo rentals available, we can ensure you and your family have a comfortable place to rest your head at night after a long day of playing in the white sand of Siesta Key.