Resultados para "River" en Ciencias de la Tierra

Scientists have long attempted to understand Earth’s past, and in service to that effort, they have divided the world’s history into eons, eras, periods, epochs, and ages. For example, the current eon is called the Phanerozoic Eon, which means “visible life”. This is the eon in which multicellular life has evolved and thrived. Before this, life was microscopic (single cells).

They say that one is subjected to a sobering sample of what can only be described as an existential crisis when traversing the golden and seemingly infinite terrain of the Sahara Desert. If one climbed any of the countless sand dunes and twirled around in a place, particularly under the starlit sky, they would scarcely be able to tell east from west without a compass, for there would be nothing but dizzying carpets of indistinguishable sand hills unfurling into the distant horizon.

As soon as man discovered writing, he began engaging in historiography (historical writing and philosophy), but paleoanthropology only really began in the late 1800s. As archaeologists began finding bones in European caves of a human race that was very different than any race in the modern world, the study of paleoanthropology was born. The race of those early humans who were found in the European caves were later termed Neanderthals, and for quite some time, they were believed to have been the race from which many modern humans were directly descended.

A sweeping, interdisciplinary history of the world's third-largest river, a potent symbol across South Asia and the Hindu diaspora. Weaving together geography, environmental politics, and religious history, Sen offers a remarkable portrait of one of the world's largest and most densely populated river basins.

Signed on November 24, 1922, the Colorado River Compact is body of laws colloquially called the "Law of the River" that governs how human beings use water from the river system dubbed the "American Nile." No fewer than forty million people have come to rely on the Colorado River system in modern times-a system immersed in an unprecedented, unrelenting megadrought for more than two decades. Attempting to navigate this "new normal," policymakers are negotiating new management rules for the river system, a process coinciding with the compact's centennial that must be completed by 2026.

The great unknown of the Southwest is conquered by a one-armed man and his crew of adventurers, placing the Colorado River and the Grand Canyon on the map of the American continent. It is a journey no human being had ever made before. Dangerous rapids, narrow canyon walls offering no escape, terrifying river waterfalls, capsized boats, near drowning, lost equipment and disillusioned men are dramatically described by John Wesley Powell, leader of this adventurous party.

The early history of Earth covers such vast stretches of time that years, centuries, and even millennia become virtually meaningless. Instead, paleontologists and scientists who study geochronology divide time into periods and eras. What humans commonly refer to as the “Ice Age” is actually a series of fluctuating climate events that have occurred throughout the planet’s history. These ongoing historical phenomena are difficult to conceptualize because of both the time frame involved and the natural process by which they cyclically unfold.

“Wonderfully written…Mr. Owen writes about water, but in these polarized times the lessons he shares spill into other arenas. The world of water rights and wrongs along the Colorado River offers hope for other problems.” —Wall Street Journal An eye-opening account of where our water...

Coursing through the Atlantic Ocean is a powerful current with a force 300 times that of the mighty Amazon. Ulanski explores the fascinating science and history of this sea highway known as the Gulf Stream, a watery wilderness that stretches from the Caribbean to the North Atlantic. Spanning both distance and time, Ulanski's investigation reveals how the Gulf Stream affects and is affected by every living thing that encounters it--from tiny planktonic organisms to giant bluefin tuna, from ancient mariners to big-game anglers.