Has Earth Always Had The Same Amount Of Water?

Researchers have examined 3.8 billion year old minerals from Greenland which are derived from the Earth’s primordial oceans in order to approximate the ancient water budget. (Credit: Image courtesy of University of Copenhagen)

The Blue Planet's New Water Budget: Do We Have Enough? -- Science Daily

ScienceDaily (Mar. 5, 2012) — Investigating the history of water on Earth is critical to understanding the planet's climate. One central question is whether Earth has always had the same amount of water on and surrounding it, the same so-called "water budget." Has Earth gained or lost water from comets and meteorites? Has water been lost into space? New research into Earth's primordial oceans conducted by researchers at the Natural History Museum of Denmark at the University of Copenhagen and Stanford University revisits Earth's historical water budget.

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