How Does the Ocean Keep Getting Taller?

The ocean is like a big bathtub that keeps getting filled up more and more every year, but no one is turning on the tap.

Imagine you have a water bottle full of water, and you drop it into a bowl of water. The water in the bowl goes up just a little bit because there’s more water now. That's what happens with the ocean: when we add more water, like from melting icebergs or melting glaciers, the water level goes up.

Think of Earth as that bowl, and the ocean is the water in it. Every year, more and more ice from places like Greenland and Antarctica melts and flows into the sea, just like when you add more water to your bowl. Over time, this makes the ocean taller, even if we can’t see it happening every day.

Sometimes, the ocean also gets taller because the ground under the ocean, called the seafloor, slowly moves up a little bit, too. It’s like pushing the bottom of the bowl upward while you add water to it.