Ice Rivers: A Story of Glaciers, Wilderness, and Humanity
By Jemma Wadham. Princeton University Press, 2021. 256 pages. $26.95
“Ice behaves more like a liquid than a solid,” British glacial biogeochemist Jemma Wadham tells us in the early pages of “Ice Rivers,” justifying the title. Most Alaskans are familiar with this concept. Our glaciers are forever moving. What we might not consider is how crucial to life those glaciers are. And as they quit behaving like liquid and instead become liquid, life both within and beyond them is changing. This is part of the story that Wadham tells in a book that seamlessly blends memoir with hard science, offering both an account of Wadham’s three decades of research and insight into the person behind it.
Wadham is well known in the field of glaciology. She made her name through groundbreaking work — or should that be icebreaking? — studying the pathways meltwater makes through a glacier in Svalbard, Norway, finding that fit took unexpected routes, and that it carried essential building blocks of life that it delivers into the sea. What’s more, through months of tedious work collecting samples of that water, she found evidence of microscopic organisms living in it. After her study, she writes, “We could no longer think of glaciers as frozen, sterile wastelands — they were as much a part of Earth’s biosphere as the forests and the oceans.”
The book begins on a personal note with a vivid description of childhood days Wadham spent roaming the Cairngorms of Scotland, across land carved by the retreating glaciers of the last ice age. She didn’t find glaciology, she indicates. Glaciology found her, and it has taken her to the ends of the Earth. Here she takes readers along.
Wadham did her undergrad work on the Haut Glacier d’Arolla in the Swiss Alps. By her own confession, she doesn’t like to be cold, but her profession demands she endure it, and it was on this first expedition that she found her obsession with glaciers was more than sufficient to offset the daily discomforts of lengthy periods living all but atop them while conducting studies. One of the lessons of this book, in fact, is that field research is not glamorous. “You’re actually there to survive,” she explains.
From Europe, Wadham plunges into the Arctic, first in Svalbard and then Greenland. She offers brief but concise and easily grasped explanations of the long history of ice on our shared planet. She can distill the complexities of the last ice age into brief passages that will acquaint readers with enough of the basics that they can understand the foundations of her work without getting lost in it. Her descriptions of the differing ways glaciers move are easily grasped. Her explanation of the makeup of glacial flour is precise. The flour, she shows, contains vital soil nutrients that sustain phytoplankton. There’s a lot to be learned here.
Greenland’s fabled ice sheet is melting, and part of Wadham’s work there was figuring out how this occurring, and how quickly. It’s no small matter. As water discharges off the shores of the island and into the ocean, global sea levels are rising, much as they did the last time the planet warmed, though that was long before humans entered the picture. Now billions of us cluster along coastal regions, and if the present rate of melting persists, low-lying cities across the planet will become flooded and uninhabitable.
For reasons involving atmospheric currents and other factors, the Antarctic ice sheet isn’t melting quite as quickly as Greenland’s but it’s slowly dripping away as well. The real concern, as Wadham’s work on the southernmost continent has helped show, is the glaciers holding back the ice sheet. They regulate the outward flow of ice coming down from the continent, slowing it. The glaciers are withering away, and if they weaken sufficiently, ice could begin flowing down rapidly, raising sea levels dramatically. And a lot of methane, an exponentially stronger greenhouse gas than carbon, is trapped beneath the ice sheet. Its release would be catastrophic on a global scale.
For most people, talk of rising sea levels brought about by remote melting polar ice sheets remains comfortably in the future, which makes it easy to ignore. Harder to overlook is the impact of melting glaciers in temperate and tropical zones. Wadham hopscotches from Patagonia to India to Peru to visit glaciers where the consequences of ice loss are more immediate.
As glaciers recede, they leave large lakes behind, lakes that are often partially contained by ice walls. Those walls are prone to collapse, sending sudden and massive surges of water tumbling down valleys. In 1941, 1,800 residents of Huaraz, Peru, perished in one such event. An instrument study Wadham carried out on the remote Rio Huemules in Chile, which is fed by the Steffen Glacier, found that it briefly swelled to 50 times its normal volume when lakes farther upstream gave way. Fortunately, the land downstream is largely uninhabited.
Even more pressing are the melting Himalayan glaciers which provide essential water to more than a billion people. Most are vanishing. “Glacier melting is one of the big humanitarian time bombs of climate change,” Wadham writes, and the communities that will be hardest hit are impoverished, and they are minor contributors of greenhouse gases.
As Wadham writes of her career, she also shares a bit of her personal life, but never enough to shift the focus primarily toward herself. She admits to bouts of depression and self-doubt, but even when a benign tumor had to be be removed from her skull, she demonstrates stereotypical British understatement by saying that “brain surgery had kind of got in the way” of her work.
Longtime Alaskans have watched our glaciers recede as well, perhaps not as closely as Wadham does, but we see it in real time. “Ice Rivers” offers an explanation of what we are witnessing, why it is happening, and what we are losing. The success of Wadham’s book is her ability to feel this loss on a personal level, and to convey to us why we all should.