Like nature documentaries on the Amazon jungle that end with the sound of chainsaws, Cynthia Barnett's new book about the weather eventually gets around to climate change. Reading "Rain: A Natural and Cultural History," a perfectly balanced book of general-interest science and boots-on-the-ground journalism, the ominous threat of what we have done to our weather hangs over the pages like dark summer thunderheads. We have arrived at the critical and intractable point in human history where the annual occurrence of too much or too little rain signals the end of Earth's ideal life-sustaining atmosphere.

To reach that conclusion, Barnett presents us with a dizzying amount of data and history. We learn that 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." And the shape of those raindrops? They are not like the pear-shaped drops that fall from our leaky faucets. They instead resemble "tiny parachutes."

The rainiest city in the United States is not Seattle — Mobile, Ala., holds that distinction with average precipitation of 65 inches. In fact, Seattle and Portland are actually drier than most major cities on the Eastern Seaboard. The driest U.S. city is Yuma, Ariz., with its parching 3 inches a year.

Floods and droughts were wonderful excuses to burn "witches" here at home and abroad — by some calculations 50,000 were slaughtered in Europe alone. Barnett found that the accusations of witchcraft rose with the coming of the Little Ice Age in the 14th century and abated only when the worst of the climate extremes lessened.

The author's historical tracing of rain with the rise and fall of civilizations such as Mesopotamia is particularly instructive today as she points to modern research that proves that "six of the 12 extreme events [in 2012] carried the fingerprint of climate change." This includes Hurricane Sandy.

Barnett writes, "After thousands of years spent praying for rain or worshiping it … humanity has managed to change the rain."

"Rain: A Naural and Cultural History," by Cynthia Barnett

When Barnett journeys to the rainiest place on Earth, Cherrapunji in northeastern India — average annual rainfall 470 inches — she does not witness the area's famed downpours. Instead, she experiences days and days of sunshine and sweat, and further proof of climate change. As they contemplate installing air conditioners for the first time, villagers "are mystified that anyone anywhere else in the world thinks otherwise."

Stephen J. Lyons is the author of three books. "Going Driftless: Life Lessons From the Heartland for Unraveling Times" will be published in May by Globe Pequot Press.