Planet Earth is a somewhat unpredictable landlord. Mostly, conditions here are benign and favourable to life, but sometimes its tenants are suddenly crushed in a violent outburst. For as long as humans have lived, we have been subjected to such natural catastrophes and have been trying to both understand and predict them. As marine scientist Dr Ellen Prager shows here, we have made great strides, but many questions and unknowns remain. Dangerous Earth is a fascinating tour to the cutting edge of the earth sciences to look at some of the complex problems for which we are still lacking answers.

Dangerous Earth: What We Wish We Knew about Volcanoes, Hurricanes, Climate Change, Earthquakes, and More, written by Ellen Prager, published by The University of Chicago Press in March 2020 (hardback, 272 pages)

Dangerous Earth is a cleverly structured book. Each chapter opens with some examples of famous or scientifically important natural disasters that in hindsight were as surprising as they were full of lessons. Having whetted the reader’s appetite with tales of destruction, Prager then walks the reader through the basic scientific facts and principles necessary to understand a particular branch of the earth sciences. The largest part of each chapter, though, is dedicated to the unknowns: the open questions, the vexing problems, and the limits of our current methods and instruments.

As the subtitle of the book implies, the usual suspects – volcanoes, earthquakes, hurricanes – are all present and correct, but Prager takes the bull by the horns and opens with climate change. And this is actually a sensible approach: she does not go quite as far as McGuire does in his book Waking the Giant, but whether certain natural disasters will be exacerbated by climate change is a question of intense interest.

Briefly introducing climate change basics and the 2002 collapse of the Larsen B Ice Shelf in Antarctica, she quickly turns to the uncertainty around sea-level rise. This means examining what is happening at the poles. From earlier reviews, I was already familiar with the rapid retreat of Greenland’s glaciers, but the book is especially up to date on the complexities of what happens at the interface between glaciers and their bedrock, and at the underside where glaciers enter the ocean. Next to the Thwaites Glacier, she mentions other Antarctic monsters most of us will have never heard of, but that will shape our future. Similarly riddled with questions is how global oceanic circulation will be affected by climate change, which means reckoning with its complex three-dimensional nature. Other matters touched on here are melting permafrost, bleaching coral reefs, and dead zones devoid of oxygen.

“[Dangerous Earth] is especially up to date on the complexities of what happens at the interface between glaciers and their bedrock, and at the underside where glaciers enter the ocean.”

The same approach is applied to the topics of volcanoes and earthquakes. Plate tectonics quite literally underlies both, so is introduced first. These are especially riveting chapters – I don’t think I will ever tire reading of the eruptions of Mount St. Helens or Laki. Meanwhile, Mount Pinatubo and the less well-remembered Nevado del Ruiz eruption also taught the geological community a lot. But the unknowns! What does the plumbing that feeds volcanoes look like? How do eruptions progress and end? What of the idea of the life cycle of a volcano: its birth, growth, and death? What of the risk of so-called flank collapses triggering enormous tsunamis? The new book Volcanotectonics offers more insights.

Earthquakes hold similar mysteries, and this field is particularly known for its attempts at prediction. Not surprising, since many cities have been built on or near faults. Prager reveals fascinating complexities and discoveries: The 1992 Landers event revealed that earthquakes can jump tens of kilometres between known segments to trigger tremors at other, unconnected faults. This has raised many questions about the randomness or relatedness of earthquakes. Do they cluster? Can they occur in swarms? Can human activities such as mining or fracking trigger tremors? Then there are the bizarre slow-slip earthquakes where tectonic plates move over days or weeks rather than instantaneously, without discernible seismic waves. This chapter provides a welcome update to a book such as Earthshaking Science. Tsunamis are bundled into this chapter. Especially the 2004 Sumatra earthquake and ensuing tsunami revealed a lot about the subtle complexities of how seafloor shape and topography – its bathymetry – can channel and redirect wave energy. As Prager writes: “It’s not exactly like dropping a pebble in a pond”.

“Earthquakes hold similar mysteries [such as] bizarre slow-slip earthquakes where tectonic plates move over days or weeks rather than instantaneously.”

What unites these first three chapters is the limits imposed by our short window of observation. Data have only been collected for a century or so, a geological blink of an eye. Many recent disasters have spurred scientists to look into the rock record for evidence of past disasters, revealing many. Some, disturbingly, can be very violent, though very infrequent, sparking new questions and concerns about e.g. supervolcanoes.

Dangerous Earth does seem to run a bit out of steam after this. After three solid 40-50–page chapters, the chapter on hurricanes clocks in at 28 pages. It still does a good job of presenting the atmospheric and meteorological mechanics, as well as the unknowns. Why do some storms intensify so rapidly? What are the links with climate change and known patterns such as El Niño? But especially, can we improve forecasts, both of the path storms will take, and the attendant risk of storm surges?

“our short window of observation imposes limits […] many recent disasters have spurred scientists to look into the rock record for evidence of past disasters, revealing many. “

The final chapter, though, felt like an unsatisfying end to an otherwise excellent book. In just 17 pages Prager mentions rogue waves, landslides, rip currents, sinkholes, and – wait for it – sharks (!). Not only does that last one feel totally out of place in a book on geological hazards, on average literally only a handful of people are killed by sharks annually. Since she notes that landslides are much more common than most people realise, an in-depth chapter on these so-called mass movements would have made for a stronger end. It could have included those sinkholes, but also erosion, avalanches, and land subsidence. Furthermore, it connects back to volcanoes and earthquakes as these are often followed by lahars and mudflows. And there are fascinating but poorly understood phenomena such as soil liquefaction during earthquakes.

That observation notwithstanding, Dangerous Earth is overall a fascinating and riveting read that really succeeds in bringing you right to the cutting edge of open questions in the earth sciences. Concerning prevention and preparedness, she echoes the sentiment in books such as The Big Ones and the recently reviewed Disaster by Choice: that we are increasingly, and foolhardily, putting ourselves in the path of destruction. Many questions remain, but we know enough to prevent a lot of the suffering and damage that accompany most natural disasters.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

Dangerous Earth hardback or ebook

Other recommended books mentioned in this review:

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

If the end of the world is something that keeps you up at night you might want to skip this book. Some might snigger at the “rogue robots” in the book’s subtitle, but End Times is a serious look at so-called existential risks. Former foreign correspondent, reporter, and editor with TIME magazine Bryan Walsh takes an unflinching look at the various disasters that could wipe out humanity, the people whose jobs it is to seriously think through catastrophic threats, and how, if at all, we can prepare ourselves.

End Times: A Brief Guide to the End of the World, written by Bryan Walsh, published by Hachette Books in August 2019 (hardback, 406 pages)

Surveying the table of contents feels like the roll call of Doomsday classroom: “Asteroid impact? Here. Volcanic eruptions? Check. Nuclear war? Thanks, your usual radiant self, I see. Climate change? Stewing in the corner over there. Pandemic and biotechnological killer virus? Thanks – please stop trying to poke each other’s eyes out. AI overlord? Check, can you please put down your smartphone? Aliens? Has anyone seen the aliens?”

Several of these topics have been the subject of book reviews here before. Walsh starts with the asteroid impact that killed the dinosaurs before turning his attention to the search for near-earth objects, covering similar ground to the recently reviewed Fire in the Sky, including the Shoemaker-Levy 9 comet, a visit to the same Catalina Sky Survey, and an interview with NASA’s Planetary Defense Officer Lindley Johnson. The chapter on volcanism covers the usual suspects, such as the Siberian Traps, the Toba volcano, the Tambora volcano, and the looming threat of the Yellowstone supervolcano.

“Surveying the table of contents feels like the roll call of Doomsday classroom.”

The threat of nuclear war is a topic that I am less familiar with, and Walsh walks you through the history of the first atomic bomb tests, the arms race during the Cold War followed by disarmament, and the recent resurgence in nuclear weapons stockpiling. Combined with the secret government war plans and the many near-misses, this makes for chilling reading.

Walsh has interviewed plenty of people while researching this book. Additionally, he draws on personal experience when writing of climate change and pandemics. He was stationed in Hong Kong during the 2003 outbreak of SARS and makes many relevant observations: vaccine resistance, the lack of investment in developing new ones, and the evolutionary trade-off between transmissibility and fatality that prevents diseases from completely wiping out their hosts.

“[Vaclav] Smil’s point about the difference in energy density between fossil fuels and renewables […] is often overlooked”

Just as Jon Gertner, he has visited Greenland’s Jakobshavn glacier (see the previous review of The Ice at the End of the World). He discusses climate change tipping points, the fiendish problem of continued global warming even if we stopped emissions now, why addressing the hole in the ozone layer was easy and curbing carbon dioxide emissions is not, and why we all need to read Vaclav Smil’s work. Smil’s point about the difference in energy density between fossil fuels and renewables, and the challenges this presents, is often overlooked.

Walsh attended the 2009 UN climate change summit in Copenhagen and it is here that he makes some of his sharpest observations on the psychology of our inaction. He notes how in Copenhagen: “no one really wanted to do all that much to slow climate change. Not if it carried any political or economic risk. Not if it could cost them their job, or restrict their citizens in almost any way. Climate change was important, sure – but not that important” (p. 137). He calls climate change “the ultimate collective action problem” and highlights how this existential threat, uniquely, foremost affects generations yet to come.

“[Walsh] calls climate change “the ultimate collective action problem”.”

The remaining threats – biotechnology, artificial intelligence, and aliens – all stand apart as ones that have yet to pass. He considers biotechnology becoming bioterrorism in the wrong hands the biggest threat of all, discussing at length the ethics, regulation, and double-edged nature of this kind of scientific research. He clarifies why there is nothing to giggle about “killer robots” if so-called artificial general intelligence were to enter the loop of recursive self-improvement and take off on an exponential curve. And the seemingly unlikely threat of alien life forms results in a chapter that nicely discusses the Drake equation, the Search for Extraterrestrial Intelligence, and some of the solutions to the Fermi Paradox (see also these two fantastic YouTube videos from Kurzgesagt).

As a reporter, Walsh knows how to write a captivating and entertaining book, even if the topic is grim. Yet I do have some concerns. I appreciate that, in tackling so many big subjects in just over 300 pages, the coverage is going to be somewhat superficial. Although he refers to peer-reviewed literature, I also noticed many references to online newspaper and magazine articles. Similarly, he seems to cite some, but not all, personal communications with people. And when mentioning the work of certain authors (e.g. Vaclav Smil), he curiously cites articles about them, rather than anything they have written.

“there is nothing to giggle about “killer robots” if so-called artificial general intelligence were to enter the loop of recursive self-improvement”

If it seems I am harping on about this, I ended up questioning how much Walsh has relied on second-hand information for this book. Although I trust that as a reporter he can judge sources for their reliability, I worry that he sometimes misses out on subtleties. A point in case is the extinction of the dinosaurs, where he sketches as dissenters those who blame massive volcanic eruptions. Although the evidence for impact is by now undeniable, the relative importance of each remains hotly debated (recent examples of palaeontologists airing different views in their books are The Rise and Fall of the Dinosaurs and The Dinosaurs Rediscovered). And the idea of a global conflagration following impact is not supported by research on fossil charcoal. Similarly, the fear of AI running rampant has its share of dissenters.

Finally, I am not sure I always share Walsh’s optimism that e.g. geoengineering will offer a solution to climate change, or that colonisation of space is the answer to an overcrowded planet. I would not want to exclude these, but I feel as much attracted to Eileen Crist’s call of scaling down and pulling back. Which brings me to two existential threats I felt were missing. What of the one-two punch of habitat destruction and rampant resource extraction? Together with climate change, they are, in my opinion, symptoms of overpopulation accompanied by increasingly widespread overconsumption. I expect these will cause global disruption before climate change can get to us.

“What of […] habitat destruction and rampant resource extraction? […] I expect these will cause global disruption before climate change can get to us.”

If a book such as Global Catastrophic Risks seems too daunting at first, End Times makes a great read as a popular introduction to existential threats. Where it concerns ethics and philosophy, or human psychology in the face of threats, Walsh makes some excellent observations. Keeping in mind above reservations, I would encourage readers to subsequently go deeper into the literature if any one of these topics fascinates them, or consider the recent book The Precipice which has similar but more in-depth coverage.

Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.

End Times paperback, hardback, ebook, audiobook or audio CD

Other recommended books mentioned in this review:

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________