Earth’s environment is in constant flux. Driven by physical processes, biological processes (now including the effects of human activity), and their interactions, incessant changes occur at virtually ...

Estimates of extreme sea-level return periods guide flood hazard mitigation. Return period estimates calculated from tide gauge records, which are relatively short (typically less than 100 years), can ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Here’s what you’ll learn when you read this story: “The Great Unconformity…represents a globally ...

Pliocene global temperatures periodically exceeded modern levels, offering insights into ice sheet sensitivity to warm climates. Ice-proximal geologic records from this period provide crucial but ...

Geochemists used thallium isotopes to track the rise and fall of free oxygen on Earth between 2.5 and 2.2 billion years ago, the process that enabled life as we know it. About 2.5 billion years ago, ...

About 34 million years ago, Earth began to cool dramatically, transforming the climate from greenhouse to icehouse and causing sea levels to fall. As more land was exposed to weathering forces, ...

This report provides an assessment of both the demonstrated and underdeveloped potential of the deep-time geologic record to inform us about the dynamics of the global climate system. The report ...

Here’s what you’ll learn when you read this story: In geological layers around the world (particularly in the southwestern U.S.) roughly one billion years of rock are missing—a mystery known as the ...