15 - Changes in desert climate

Summary

In deserts, that which seems eternal may change overnight, and that which is least expected is always possible.

Susan Arritt, American natural-science writer Deserts (1993)

He went on to talk about the colors of the desert, how they had been formed through the cooling of the earth; … he spoke about the … earth moving into strange new zodiacal realms and flopping over on its axis; about the great climatic changes, sudden, catastrophic changes burying whole epochs alive, making deserts into tropical seas and pushing up mountains where once there was sea, and so on. He spoke fascinatingly, lingeringly, as if he had witnessed it all himself from some high place in some ageless cloak of flesh.

Henry Miller, American author The Air-conditioned Nightmare (1945)

May sickened into June. The short-grass curled.

Of evenings thunder mumbled 'round the sky;

But clouds were phantoms and the dawns were dry,

And it were better nothing had been born.

John Neihardt, American poet The Twilight of the Sioux (1925)

Deserts have developed and disappeared on the grand geological time scales of continental drift, spanning hundreds of millions of years. However, the episodic expansions and contractions of the deserts during the present Quaternary Period will be the focus of this chapter. The Quaternary Period encompasses the Pleistocene Epoch, the previous 1 000 000 years of glacial and interglacial periods, and the most recent 10 000 years, the Holocene Epoch.