Published: April 10, 2015

    Pelican for Parents: Explaining Why Oceans Are Salty to Your Kids

    As they explore their surroundings and discover the breathtaking scope of the world, children begin asking a number of questions that can challenge their parents. While some ask about the color of the sky or the origins of their siblings, others are fascinated by geological questions centering on the nature of water.

    Oceans, Lakes and Swimming Pools

    If you live near the beach, you’ve probably had to warn your child against drinking salty ocean water. From a young person’s point of view, this raises an intriguing question about why this water is different from the water in lakes, ponds, and the backyard swimming pool. To effectively answer, it’s important to know the facts.

    Where Exactly Does the Salt Come from?

    Covering about 70 percent of the Earth’s surface, the oceans contain the vast majority of the planet’s water. In fact, approximately 97 percent of all the Earth’s water is saline. The main reason for this has to do with the low-lying nature of the oceans, which basically act as reservoirs for the land’s mineral runoff.

    As rain falls, it collects some dissolved carbon dioxide from the air, giving it a mild acidic quality that allows it to dissolve minerals. As it slowly erodes rock, rainwater carries salt and minerals into streams, which feed rivers that ultimately, eject their contents into the oceans.

    With that said, the oceans also get some of their salt content from below the planet’s surface. Deep within the floors of the oceans, hydrothermal vents feed salt and minerals into surrounding water, as do underwater volcanoes, which frequently erupt without our knowledge.

    Breaking it All Down

    While older children may have the capacity to understand the technical reasons behind ocean salinity, younger kids usually do not. In these instances, you can explain the concept better by citing the father of modern chemistry, Antoine Lavoisier, who once called oceans the “rinsings of the Earth.” In effect, rain washes the land of salt, which drains into the lower-lying oceans.

    You can also take this opportunity to explain that, while some salt can be harmless, too much can be problematic – not just to our health – but to the environment. For instance, by ejecting salty brine into the land and rivers, traditional salt-based water softeners can significantly damage plant life, agriculture and wildlife in and around lakes and streams. For this reason, more and more communities are forbidding their use, causing residents to opt for modern salt-free devices, such as Pelican’s NaturSoft® Water Softener Alternative with Salt Free Technology.