Has Sea Level Changed Throughout Earth’s History?

OCTOBER 27, 2019 – 5:00 AM  

By MARILYN VOS SAVANT 

(iStock)

I know the Earth’s land areas have changed significantly over the ages, but has sea level always been the same?

—Richard Shinar, Scottsdale, Arizona

No. Today, land areas cover about 29 percent of the globe, which means the oceans cover 71 percent. This share of land area is almost the largest in history. (The most was 30 percent.) During one past era, land covered only 13 percent of the planet, and so oceans covered 87 percent. The numerical difference (29 percent land now versus 13 percent land then) doesn’t seem huge, but it means the Earth once had less than half as much land above water than it does now. To us humans, who live on land, the difference is enormous.

On October 27, 2019   /   Enviromentalism   /   Leave a comment