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  MORE ADVANCE PRAISE FOR RAIN

  “Like the weather, there’s no predicting the delightful and sometimes disturbing surprises waiting on every page of Rain. Whether she’s writing about Mesopotamia or the Met Office, Cynthia Barnett illuminates the hidden connections that tie our fate to a precious resource we neglect at our peril.”

  —DAN FAGIN, author of the Pulitzer Prize–winning Toms River: A Story of Science and Salvation

  “Rain is one of the most elegant and absorbing books ever written about the natural world. Writing with grace and imagination, Cynthia Barnett takes you on a journey into the heart of the most elemental force in our lives. An important, revelatory, and thoroughly wondrous book.”

  —WILLIAM SOUDER, author of On a Farther Shore: The Life and Legacy of Rachel Carson

  “Captivating and compelling, a delightful celebration of precipitation that is brimming with insight. Whether you’re desperate for more of it or you just wish it would stop, you’ll never think of rain in the same way again.”

  —GAVIN PRETOR-PINNEY, author of The Cloud Collector’s Handbook

  “Barnett’s beautifully written book envelops the reader in a warm shower of intriguing history and fascinating science. Anyone who looks longingly at rain clouds, rejoices in a spring downpour, or frets about drought will love Rain.”

  —DANIEL CHAMOWITZ, author of What a Plant Knows; director, Manna Center for Plant Biosciences, Tel Aviv University

  “Rain is one of those uncommonly wonderful books that are both highly significant and deeply pleasurable to read. As we face the coming time of storms, of flood and drought, nothing will be more important than rain. So all gratitude to Cynthia Barnett for writing a book that is clear, surprising, and filled with fascination.”

  —KATHLEEN DEAN MOORE, author of Riverwalking: Reflections on Moving Water

  “Cynthia Barnett looks at the human relationship to rain—from Noah to Thomas Jefferson to our own conflicted attitudes. The result is a book of unexpected connections and wonderful surprises. It will give you more respect for every rainstorm you experience, and more joy in the raindrops.”

  —CHARLES FISHMAN, author of The Big Thirst: The Secret Life and Turbulent Future of Water

  “If you care about this planet, you’re lucky that Cynthia Barnett writes so elegantly and intelligently about the stuff that falls on it. It’s kind of ironic—like rain on your wedding day?—that the folly of mankind’s relentless efforts to control the earth’s water has inspired Barnett’s best work yet.”

  —MICHAEL GRUNWALD, author of The Swamp: The Everglades, Florida, and the Politics of Paradise

  “A seamless blending of personal narrative with scientific and cultural explanations…Fans of Mary Roach will recognize a similar ease of style and interjection of wit…. Accessible to every reader, from the environmental scientist to the parent choosing whether their child needs to wear a raincoat that day.”

  —LIBRARY JOURNAL (starred review)

  Copyright © 2015 by Cynthia Barnett

  All rights reserved.

  Published in the United States by Crown Publishers, an imprint of the Crown Publishing Group, a division of Penguin Random House LLC, New York.

  www.​crownpublishing.​com

  CROWN and the Crown colophon are registered trademarks of Penguin Random House LLC.

  Library of Congress Cataloging-in-Publication Data

  Barnett, Cynthia, 1966–

  Rain: a natural and cultural history / by Cynthia Barnett.—First edition.

  pages cm

  Includes bibliographical references.

  1. Rain and rainfall. 2. Weather. 3. Rainfall anomalies. 4. Droughts. 5. Physical geography. 6. Climatic changes. 7. Earth sciences. I. Title.

  QC925.B315 2014

  551.57’7—dc23 2014034180

  ISBN 9780804137096

  eBook ISBN 9780804137102

  eBook design adapted from printed book design by Gretchen Achilles

  Cover design by Anna Kochman

  Cover photograph: Ryan McVay/Getty Images

  v4.1

  a

  FOR AARON

  CONTENTS

  Cover

  Title Page

  Copyright

  Dedication

  Epigraph

  PROLOGUE Origins

  I ELEMENTAL RAIN

  ONE  Cloudy with a Chance of Civilization

  TWO  Drought, Deluge, and Devilry

  THREE  Praying for Rain

  II CHANCE OF RAIN

  FOUR  The Weather Watchers

  FIVE  The Articles of Rain

  III AMERICAN RAIN

  SIX  Founding Forecaster

  SEVEN  Rain Follows the Plow

  EIGHT  The Rainmakers

  IV CAPTURING THE RAIN

  NINE  Writers on the Storm

  TEN  The Scent of Rain

  ELEVEN  City Rains

  V MERCURIAL RAIN

  TWELVE  Strange Rain

  THIRTEEN  And the Forecast Calls for Change

  EPILOGUE  Waiting for Rain

  Acknowledgments

  Notes

  About the Author

  And who art thou? Said I to the soft-falling shower,

  Which, strange to tell, gave me an answer, as here translated:

  I am the Poem of Earth, said the voice of the rain,

  Eternal I rise impalpable out of the land and the bottomless sea,

  Upward to heaven, whence, vaguely form’d, altogether changed, and yet the same,

  I descend to lave the drouths, atomies, dust-layers of the globe,

  And all that in them without me were seeds only, latent, unborn;

  And forever, by day and night, I give back life to my own origin, and make pure and beautify it;

  (For song, issuing from its birth-place, after fulfilment, wandering,

  Reck’d or unreck’d, duly with love returns.)

  WALT WHITMAN

  “The Voice of the Rain”

  1885

  PROLOGUE

  ORIGINS

  The rain on Mars was gentle, and welcome. Sometimes, the rain on Mars was blue. One night, rain fell so marvelously upon the fourth planet from the sun that thousands of trees sprouted and grew overnight, breathing oxygen into the air.

  When Ray Bradbury gave Mars rain and a livable atmosphere in The Martian Chronicles, science fiction purists grumbled that it was completely implausible. In the previous century, astronomers—and writers like H. G. Wells who borrowed from their work to give sci-fi a tantalizing authenticity—had seen Mars as Earthlike, odds-on favorite for life on a planet other than our own. But by the time The Martian Chronicles was published in 1950, those odds had changed. Scientists viewed Mars as chokingly dry, impossibly harsh—and far too cold for rain.

  Bradbury didn’t care to conform to the scientific views of the day. On any planet, he was much more interested in the human story. He created a rain-soaked Venus, too, but not because scientists then considered it a galactic swamp. Bradbury just loved rain. It fit his melancholy like a favorite wool sweater. As a boy, he had loved the summer rains of Illinois, and those that fell during family vacations in Wisconsin. Hawking newspapers on a Los Angeles street corner as a teen, Bradbury never minded a late-afternoon deluge. And in his eighty years of writing every day, raindrops tap-tap-tapped from the typewriter keys into many a short story and every book.

  A Bradbury rain could set a gentle scene or a creepy one. It could create moods of gloom, mania, or joy. In his short story “The Long Rain,” he made rain a character all its own: “It was a hard rain, a perpetual rain, a sweating and steaming rain; it was a mizzle, a downpour, a fountain, a whipping at the eyes, an undertow at the ankles; it was a rain to drown al
l rains and the memory of rains.”

  So often making rain the mise-en-scène for life, Bradbury was onto something. Everyone knows that life could not have developed without water. Life as we define it required a wet and watery planet. But the Earth-as-exceptional-blue-marble story many of us grew up with is, in some ways, as much a product of the human imagination as the warm Mars sea of The Martian Chronicles. Modern scientists have good evidence that Earth did not develop as the sole wet and watery orb in our solar system. Earth, Mars, and Venus were born of the same batch of flying fireballs. All three boasted the same remarkable feature: water.

  What’s exceptional about our blue marble is not that we had water. It’s that we held on to it, and that we still do. While the ancient oceans of Venus and Mars vaporized into space, Earth kept its life-giving water.

  Luckily for us, the forecast called for rain.

  —

  As even-tempered as it grew up to be, Earth started off 4.6 billion years ago as a red-faced and hellish infant. The universe had been unfolding for about 10 billion years. A new star, the sun, had just been born. Its afterbirth—cold gas and dust and heavier minerals and flaming rocks—was flying about, beginning to orbit. The heavy debris gravitated to the sun, where temperatures were well suited for rock and metal to condense. That’s why the four planets closest in, known as the terrestrials, are all made of essentially the same stuff.

  For its first half-billion years, Earth was a molten inferno some 8,000 degrees Celsius—hotter than today’s sun. Scientists call this violent era the Hadean, from the Greek word Hades, or hell. Time and again, the young Earth built up a crust, only to see it incinerated by storms of flaming meteors.

  Inside the fiery storms, though, was a lining better than silver. Virtually all of the rocks that made Earth had water locked inside. Water is a remarkable shape-shifter, able to change from liquid to solid—or to gas when it needs to make an escape. As meteorites crashed onto Hadean Earth and split apart, they spewed out water in the form of vapor. This was water in its gas form, no different from the steam rising from a boiling pot on the stove. In a sort of geologic burping contest, both the crashing boulders and young Earth’s rising volcanoes disgorged water vapor and other gases into the Hadean atmosphere.

  All that water vapor would prove an invisible redeemer. Today, at any moment, more water rushes through the atmosphere than flows through all the world’s rivers combined. The molecules speed around like pinballs, bouncing off one another, off other types of molecules, off dust and salt from sea spray. Only when air cools do they slow and begin to stick together, latching on to the gritty particles. When billions of them have condensed, they form tiny liquid droplets. Billions of the droplets, in turn, become clouds in the sky. This is the beauty of water vapor: It falls back to Earth as rain.

  When Earth was still a molten mass and hot as Hades, the vapor could not condense. Instead, it hissed away into space. Eventually, though, it began to build up in the young planet’s atmosphere. Water vapor is a heat-trapping, or greenhouse, gas just like carbon dioxide. The more gas that built up, the hotter and hotter Earth became—melting the forming crust all over again as the flaming boulders continued to fall like bombs from outer space.

  About half a billion years after it started, the blitzkrieg began to wind down. As the last of the flaming chunks fell to the surface or hurtled away, the planet finally had a chance to cool. The water vapor could condense.

  At long last, it began to rain.

  —

  In 1820, John Keats lamented in his narrative poem Lamia how little science leaves to the imagination. The scientist’s cold philosophy and dull catalog, the English poet wrote, might as well “unweave a rainbow.” The mystery of the rainbow—viewed by many throughout the world as a passageway between heaven and Earth—was dashed, Keats charged, when Isaac Newton explained the optical truth: Rainbows are the refraction of sunlight through raindrops.

  Yet Newton was anything but unimaginative. To conceive of gravity, he had to imagine Earth pulling an apple from a tree, pulling the very moon into our orbit. It takes such an eye to picture Earth’s first rains—the greatest storms of all time. So much of the young planet was destroyed during the Hadean that scientists have scant physical evidence to suggest exactly when the earliest rains began, what they looked like, and how long they poured.*

  The best clues to the first rains lie in Western Australia’s Jack Hills. Deep in the craggy orange sandstone there, geologists have dug up tiny grains of zircon that clock in as the oldest terrestrial material found on Earth to date. Nature’s trustiest timepiece—the radioactive element uranium—dates the tiny zircons back 4.2 billion years. By then, their chemistry suggests, primeval rains had begun to fall and pool on the Earth’s crust. Those earliest lagoons likely boiled away repeatedly in the Hadean’s grand finale, called the Late Heavy Meteorite Bombardment, which also cratered our moon.

  Only when the meteor storms let up could the great rains let loose. By this time, scientists infer, baby Earth was swaddled in vaporous clouds. So many volatiles had built up in the atmosphere, they moiled the sky thicker than a Newfoundland sea fog, blacker than a line of tornadoes on the Great Plains.

  Still, Earth’s charred surface likely remained so hot that the rains fell only partway to the ground, evaporating again and again. The Stygian clouds grew impossibly heavy. Lightning, its charges tied to the amount of water in the air, illuminated the lonely scene.

  The water vapor accumulated in the upper atmosphere for so long that when the surface finally cooled enough for the rains to touch down, they poured in catastrophic torrents for thousands of years. This was the picture the Stanford University geochemistry professor Donald Lowe painted for me when I asked him to imagine Earth’s first rains. Lowe is known for his research on the surface of early Earth and the deepest sediments of today’s oceans. He grew up in rain-starved California and lives there now, but he spent half his career at Louisiana State University in Baton Rouge, one of the rainiest cities in the United States. And so it is no surprise that he imagines the first rains like the gullywashers of southern Louisiana, so dense that motorists ease over to the side of the road to wait out the deluges that rap on their car roofs like a steel band’s drumroll.

  —

  In Ray Bradbury’s 1950 story “The Long Rain,” later featured in the film The Illustrated Man starring Rod Steiger, four Earthmen crash their rocket ship on a Venus drowning in such torrents. The spacemen trek through the sopping Venusian jungle in search of warm, dry shelters known as Sun Domes. They have no gear, not even hats to keep the streaming rain from pounding their heads and seeping into their ears, eyes, noses, and mouths. They have no shelter, for their rocket ship has been contaminated, and Venus’s swampy undergrowth drips as much as its skies. As they search for the cozy Sun Domes, the rain drives each man mad.

  With his aqueous Venus, Bradbury, this time to the satisfaction of the planetary purists, reflected the common scientific beliefs of the day. The irony is that in the 1960s, real spaceships discovered that Venus was dry as dust. Conventional wisdom swung from the early view that Venus was waterlogged to the hypothesis that it was always parched.

  Today, the evidence has most planetary PhDs convinced that Venus once had what Earth had—water vapor condensing to epic rains that turned much of the surface to liquid—but somehow lost it. Mars, too, appears to have begun life with a warm, wet climate, a huge ocean of water covering nearly a third of its sphere, river valleys carved by rainfall, deltas as expansive as the Amazon’s.

  Like many planetary scientists, David Grinspoon, chair of astrobiology at the Library of Congress, was drawn to the field by the science fiction writers of his boyhood, including Bradbury and Isaac Asimov, whose book Lucky Starr and the Oceans of Venus first piqued his interest in the lost Venusian seas. Earth, Mars, and Venus “started out wet,” Grinspoon explains, “drenched by the same scattershot rain of planet pieces.” Grinspoon is a musician in a funk band called House Ban
d of the Universe. In the case of Mars and Venus, the question is a twist on the old Creedence Clearwater Revival song: What stopped the rain?

  Venus, closer to the sun, appears to have become too hot, its oceans vaporizing away. The searing heat kept the vapor from condensing and completing the circle as rain. Remember that water vapor is a greenhouse gas—more potent than carbon dioxide or any other. The more that built up in the Venusian atmosphere with no rain, the hotter the planet became. This cycle, known as a runaway greenhouse effect, usurped the water cycle. Venus cooked.

  Mars, on the other hand, became too cold. Scientists believe the red planet was once wrapped in a thick atmosphere that kept it warm enough for bountiful water. From today’s dry and dusty Mars, NASA’s orbiters and rovers beam home evidence of rain-carved channels, branching rivers, deltas that might have carried ten thousand times the flow of the Mississippi River. Over perhaps hundreds of millions of years, the cozy Martian air turned cold and thin. The rains dried up. The flowing waters vanished.

  Water still exists on Mars—frozen in its polar ice caps and rocks, hidden deep below ground, and in a touch of water vapor in the atmosphere. But whatever frigid hydrologic cycle that remains is not driven by rain.

  While Venus grew too hot and Mars too cold, Earth kept just the right atmosphere to hold its water in balance—to hold the rains that turned our fiery young planet blue. Those first rains cooled the hell-charred Earth. They filled its craters and crevices until the ground could absorb no more. They spilled across the meteorite-ravaged terrain, cutting channels that became Earth’s first rivers. The rains became the land’s first lakes. The lakes spread across the steaming landscape like pools in a rising tide. Over years and decades and centuries, the liberated rains filled great basins and became oceans. Over still more time, they seeped down below the land and sea, filling aquifers that now hold far more freshwater than all our lakes and rivers combined.