ADVENTURES IN VOLCANOLAND: What Volcanoes Tell Us About the World and Ourselves, by Tamsin Mather
I live on a hump of pink granite, part of a geological formation that stretches across southern Connecticut, lurching out of the ground here and there like a pod of surfacing whales.
Before my wife and I bought our house, we had an inspector give it a look. “Well,” he said, “your foundation goes down a thousand miles into the Earth — so nothing to worry about there.”
We have been atop this tranquil bedrock for over two decades, and with every year it gets harder for me to imagine living in a place like Iceland or Indonesia — where there is much to worry about, because the solid Earth turns to liquid, ash or gas and flies out of volcanoes.
Tamsin Mather, a geologist at the University of Oxford, has no such difficulty. She has spent her career visiting volcanoes to understand how they work, and she has come to see Earth not as a peaceful world encased in a stable crust, but a globe of barely contained geological storms.
“Adventures in Volcanoland” is organized around trips Mather has taken throughout her career, starting with Vesuvius, which she first visited as a child on a family vacation. Next comes the Nicaraguan volcano Masaya, which she studied as a graduate student, and then volcanoes on other continents.
Mather’s book is intended for readers like me: novices who wouldn’t know the difference between pumice and tephra if they both hit us on the head. At times, however, it reads like a textbook, its sentences burdened with encyclopedic digressions.
She seems in these passages to be lecturing to volcanologists in training: “Using these compilations of the size and timing (often determined by measuring the activity or concentrations of radioactive elements in the rocks associated with the eruption) of different types of eruption we can draw out trends,” Mather writes. “We”? Not me.
In other places, “Adventures in Volcanoland” becomes lyrical. On a family outing in southwest England, Mather shows her children a palmful of sand “to conjure for them from their leaf-dappled glint in the summer sunlight the great batholithic magma body within which these crystals grew.” On her visits to Masaya, she watches green parakeets fly by the crater and listens to colonies of bees buzzing in its soft volcanic soil.
For all the beauty Mather perceives in volcanoes, however, she never forgets the danger they pose. “When, in awe, they take your breath away, there is always the risk that one day they won’t give it back,” she writes.
Yet Mather sees volcanoes as more than agents of destruction. They helped build the planet. When the young Earth was covered by a global ocean, Mather writes, volcanoes began “fashioning islands and then continents, pushing this new land out of the seas.”
We may owe our own existence to volcanoes. It is possible that deep-sea volcanic heat, or lightning during eruptions, “helped to rearrange some of Earth’s atoms into the first primitive molecular building blocks, allowing biology somehow to begin,” Mather speculates.
In her own research, Mather has specialized in measuring the gases that volcanoes emit. Even when they’re not erupting, volcanoes release vast amounts of carbon dioxide. Without that heat-trapping gas, an icehouse effect would replace the greenhouse effect, and the planet’s temperature would chill by nearly 60 degrees.
For the most part, Earth is able to keep its climate stable. While volcanoes warm the planet, chemical reactions draw off carbon dioxide from the air, ultimately delivering it deep underground.
This planetary thermostat is not enough to keep volcanoes from periodically unleashing hell, though. Vast eruptions may be responsible for most of the mass extinctions in life’s history.
Climate deniers point to the gigantic amount of carbon dioxide released by volcanoes to downplay our own impact on the climate. But to Mather, the comparison drives home just how dire a crisis we’ve put ourselves in. “These natural emissions pale into insignificance compared to what humans produce,” she warns.
With our cars and coal-fired plants, we have created a super-volcano. And if the past is any guide, we are endangering millions of species with extinction, perhaps including our own. “If this current mass extinction plays out, it will be alongside the human experiment, and when it’s over the Earth’s volcanoes will still be here, presiding over whatever planet we leave behind,” Mather writes.
Mather’s book has unsettled my thoughts about my home. The pink granite below me gives me as firm a foundation as I could hope for, and yet this too started out as a vast molten blob that pushed up through the Earth’s crust hundreds of millions of years ago. It cooled into a hard, crystalline rock, and when the softer overlying layers eroded, the granite saw the sun.
It will remain solid for my own lifetime, but millions of years from now, Volcanoland may well send up another mass of magma that will cover this land in fresh violence.
ADVENTURES IN VOLCANOLAND: What Volcanoes Tell Us About the World and Ourselves | By Tamsin Mather | Hanover Square | 374 pp. | $30