The Atlantic Ocean Grows 2.5cm Wider Every Year

Right now, as you read this, the Atlantic Ocean is getting wider. The distance between North America and Europe increases by about 2.5 centimetres every single year—roughly the same rate your fingernails grow. It doesn't sound like much, but over a human lifetime of 80 years, that's nearly 2 meters of new ocean floor.

This relentless expansion happens along the Mid-Atlantic Ridge, an underwater mountain range that runs down the center of the Atlantic Ocean like a zipper. Here, the Earth's crust is literally tearing apart as the North American and Eurasian plates drift in opposite directions.

How Seafloor Spreading Works

Deep beneath the ocean, magma wells up through the rift at the Mid-Atlantic Ridge. As this molten rock hits the cold seawater, it solidifies into new oceanic crust. The process pushes the existing seafloor outward on both sides, like a very slow conveyor belt running in reverse.

Scientists can measure this spreading using GPS technology with millimeter precision. They've confirmed that the rate has remained remarkably consistent: about 2.5 cm per year on average, though it varies slightly along different sections of the ridge.

The Slowest Show on Earth

While 2.5 cm per year might seem glacially slow, it's actually one of the slowest spreading rates on the planet. The East Pacific Rise, by comparison, spreads at 6-16 cm annually—up to six times faster. But don't let the Mid-Atlantic's leisurely pace fool you. This process has been running for millions of years.

What 2.5 cm per year adds up to:

• 25 meters per millennium
• 25 kilometers per million years
• Enough to transform a narrow inlet into the vast Atlantic Ocean over 200 million years

From Tiny Crack to Mighty Ocean

The Atlantic Ocean didn't always exist. About 200 million years ago, the continents we now call Africa, Europe, North America, and South America were all smashed together in a supercontinent called Pangaea. Then the Earth's crust began to crack, and magma started oozing up through the gap.

That ancient rift grew into today's Mid-Atlantic Ridge, and at 2.5 cm per year, it's pushed those continents thousands of kilometers apart. The Atlantic has grown from a narrow seam into an ocean spanning 6,400 kilometers at its widest point.

So yes, Europe and North America really are drifting apart—slowly but surely. At the current rate, in 50 million years, the Atlantic will be about 1,250 kilometers wider than it is today. Pack your patience if you're planning to walk across.