A massive ocean asteroid impact could trigger a tsunami taller than skyscrapers, flooding entire continents with almost no warning. Scientists tracking near-Earth objects say a strike in deep water would displace billions of tons of water instantly, sending waves racing across oceans at jet speed.

The asteroid that struck near the Yucatan Peninsula 66 million years ago ended the Mesozoic era and eliminated roughly 80 percent of life on Earth. The impact created a crater more than 100 miles wide and triggered a series of natural disasters, including a tsunami that remains the largest known in the planet’s history.The Chicxulub asteroid, believed to have originated in the outer solar system,…

In a Washington coastal town, residents built a towering escape structure because the roads simply won’t survive a major tsunami. The elevated refuge is designed for those with no time—or means—to flee the incoming wave.

The coastal town of Westport, Washington, sits on a narrow peninsula of sand where the ground rises only a few feet above sea level. In the event of a major earthquake off the Pacific Northwest coast, officials estimate that a tsunami could send water 30 to 40 feet high into the town within 15 to 30 minutes of the shaking starting. Because the roads leading out of town are expected to be damaged o…