How Does Ocean Water Turn Into a Sheet of Ice?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. How does ocean water turn into a sheet of ice?

The Big Idea

Ocean water turns into ice when it gets cold enough, but salty water needs to be colder than freshwater to freeze! Tiny crystals start the process. Let's watch it happen.

Salty Freeze

Step one: salty freeze. Freshwater freezes at 32 degrees Fahrenheit, or 0 Celsius. Salt in the sea lowers that to about 28.8 degrees Fahrenheit, or minus 1.8 Celsius. That is why the ocean stays liquid even below freezing.

Slush Soup

Step two: slush soup. When the air gets colder, tiny ice crystals form in the top layer of the sea. They join into a slushy soup. Wind and waves keep the soup moving until it thickens.

Solid Sheets

Step three: solid sheets. The slush freezes into solid sheets. In winter, sea ice can spread across millions of square miles. Sea ice that forms this way can last for months.

A Closer Look

Let's take a closer look! Very cold air chills the sea surface. Tiny crystals appear in the water. They bunch up into slush. Then the slush locks into solid ice. The same steps happen all over the Arctic each autumn.

Quick Facts

Quick facts! Seawater freezes at about 28.8 degrees Fahrenheit. Sea ice grows from the bottom up as well as the top down. In winter, it covers millions of square miles. Do freezer tests with a grown-up.

Think Like a Scientist

Now, think like a scientist! With a grown-up, put a cup of tap water and a cup of very salty water in the freezer. Check after an hour. Which one freezes first? Do not taste either one! Write down what you found.

Outro

Salt makes seawater freeze at a colder temperature. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!