This is the second of a two-part dive into the story of oceans on Earth and elsewhere, following my review of Ocean Worlds. That book gave a deep history of how our oceans shaped Earth and life on it and briefly dipped its toes into the topic of oceans beyond Earth. Alien Oceans is the logical follow-up. How did we figure out that there are oceans elsewhere? And would such worlds be hospitable to life? Those are the two big questions at the heart of this book. If there is one person fit to answer them, it is Kevin Peter Hand, a scientist at NASA’s Jet Propulsion Laboratory and their deputy chief for solar system exploration.
Alien Oceans: The Search for Life in the Depths of Space, written by Kevin Peter Hand, published by Princeton University Press in March 2020 (hardback, 248 pages)
A major question in astrobiology is whether the evolution of life on Earth is a fluke, or whether life is bound to pop up wherever conditions are favourable. Hand very neatly frames this in the bigger history of science. Over the centuries, we figured out that the laws of physics, chemistry, and geology work beyond Earth. But “when it comes to biology, we have yet to make that leap. Does biology work beyond Earth?” (p. 15). What we have learned is that life as we know it needs water. And though there is no shortage of theories on the origins of life, oceans are very likely where it started, and thus a logical first place to start looking for answers.
If you have any interest in astrobiology, you will probably have heard of the concept of a habitable zone or Goldilocks zone where, based on the distance to a star, conditions for life are just right. Not so close as to be too hot, nor so far as to be too cold. Earth obviously falls in that zone. Next to many minor insights, Alien Oceans had three major eye-openers for me. This was the first one:
There are other Goldilocks zones.
Depending on the details of their orbit, moons can experience such strong tidal tugs from their parent planet that the constant squeezing and stretching of the rock creates enough heat through internal friction to sustain liquid water. The physics of water helps, as it has a seemingly mundane but rather unusual property. Ice floats. When water solidifies, its density decreases slightly. What this means for moons is that the liquid water exposed to the cold of deep space freezes and forms a protective icy shell. Most liquids do not have this useful property. When they freeze, they sink to the bottom exposing more liquid until all of it is frozen solid. To top it off, ice is also a good thermal insulator, helping such ocean worlds retain heat. Maybe I have been hiding under a rock, but this was revelatory for me. Suddenly, the amount of cosmic real estate suitable for life has increased quite dramatically. And we have some of it right here on our doorstep.
The existence of oceans in our solar system and how we gathered the evidence is one of the two major threads running through this book. Hand examines this in detail for Jupiter’s moon Europa, which has been studied in the most detail. Three types of data are typically gathered: spectroscopic, gravimetric, and magnetometric. This is where Hand gets fairly technical, though, fortunately, he extensively uses comparisons with everyday concepts and technologies to help you understand the underlying (astro)physics. Without retreading his careful explanations, in Europa’s case, these different strands of data all converge on a moon with an icy shell and a substantial subsurface ocean some 80–170 km thick as the best explanation. Mixed in with this narrative are the details and many technical setbacks of the Galileo mission that are nail-bitingly tense in places.
Similar missions and measurements have been done for Saturn’s moons Enceladus and Titan, Jupiter’s moons Ganymede and Callisto, Neptune’s moon Triton, and Pluto. The evidence for oceans gathered so far gets less robust in this order, but there are some notable variations on the theme. Enceladus ejects spectacular plumes of water and carbon compounds that were photographed and sampled by the Cassini–Huygens mission. Ganymede, meanwhile, is so large that the bottom of its ocean might consist of an exotic form of dense ice, ice III, formed at very high pressures not seen on Earth, meaning its ocean is sandwiched between two layers of ice.
So you have found exo-oceans. Now what? Can we expect to find life here? That is the second major thread. Hand identifies five conditions for life to emerge: a solvent such as water, chemical building blocks, an energy source, catalytic surfaces, and time. Interestingly, there is a gap between two schools of thought. The top-down explanation deconstructs life backwards in time until we arrive at an RNA world, but how did that get started? The bottom-up explanation has shown that life’s basic building blocks such as amino acids exist in space, but how do we go from there to larger functional molecules?
This was the second major eye-opener for me: “Our environment is full of chemical disequilibrium […] there are reactions just waiting to happen. […] The metabolisms that drive life accelerate reactions in the environment, releasing energy faster than would have occurred without life” (p. 144). Hand takes a leaf out of Nick Lane’s book The Vital Question (which, shame on me, I still have not read) when he enthusiastically concludes that “the why of life is metabolism” (p. 146), offering the universe a pathway to increase entropy faster. These are remarkable ideas that give a whole new meaning to philosophical questions on the meaning of life.
The third and final eye-opener concerns the need for a catalytic surface, which is where Hand circles back to oceanographic exploration here on Earth, a recurrent theme in this book. When the submarine Alvin discovered hydrothermal vents in 1977 and found them teeming with life, these quickly became a popular alternative explanation to warm tidal pools as a place where life could have started. These so-called black smokers are powered by magma rising to the surface at mid-ocean ridges, jetting out superheated water of over 400 °C. Though volcanism and tectonics are, or sometimes were, common processes on many solar system bodies, there is another option. Alkaline vents, first discovered in 2000 at the Lost City hydrothermal field, are powered by exothermic (energy-releasing) reactions between water and mineral-rich rock, heating water to a more gentle 70–100 °C. All these need are the right rocks with cracks in them so water can percolate down.
Hand raises many other interesting questions towards the end of the book, of which I will mention just three. One, life’s metabolic reactions require so-called oxidants, oxygen being “the most glorious of oxidant” (p. 162), but how would these get down into subsurface oceans? Two, how contingent or convergent is the evolution of life’s biochemistry? Carbon is a suitable building material for life as it is “hands down the best team player on the periodic table” (p. 212). But does physics restrict us to these options, or can we sketch a periodic table of life with other, weirder possibilities? And three, how should we seek for signs of life? What makes a good biosignature? This is discussed far more in-depth in Life in the Cosmos, but Hand considers three types of evidence.
Alien Oceans limits itself to oceans in our solar system, not touching on the topic of exoplanetary oceans. Given this is not Hand’s expertise, that is reasonable. He also glosses over the question of what aliens might look like, though he speculates on the likelihood of intelligent life in ice-covered subsurface oceans. Even without these topics, Alien Oceans is information-dense, requiring me to make a summary, and then a summary of that summary while preparing this review. Nevertheless, it is an intellectually very rewarding book and the many analogies make it accessible. I enjoyed it as a follow-up to Ocean Worlds but it is a fine standalone book. Terribly fascinating, Alien Oceans makes a convincing case for exploring the moons in our solar system in the search for extraterrestrial life.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
Other recommended books mentioned in this review:
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Since it was coined in the year 2000 by Paul Crutzen and Eugene Stoermer, the term “Anthropocene” has taken the world by storm – pretty much in the same way as the phenomenon it describes. Humanity’s impact on the planet has become so all-encompassing that it warrants giving this period a new name. As a colloquial term that is all snazzy, but are we actually leaving a tangible trace in the rock record to signal a transition to a new period?
The Anthropocene as a Geological Time Unit: A Guide to the Scientific Evidence and Current Debate, edited by Jan Zalasiewicz, Colin N Waters, Mark Williams, and Colin Peter Summerhayes, published by Cambridge University Press in March 2019 (hardback, 361 pages)
Several authors have already written thought experiments to try and answer this question. But the real answer lies in the realm of stratigraphy, the geological subdiscipline that studies rock layers. As with many other conventions, to ensure scientists around the globe all talk about the same thing and use the same names, there is an official body for that. The International Commission on Stratigraphy (ICS) formally decides on naming and dating of geological periods and maintains the International Chronostratigraphic Chart, better known as the Geological Time Scale (find a PDF here).
Formal acceptance of a new name means clearing a raft of bureaucratic and academic hurdles first. So, in 2009, the editors of the current book got together to form the Anthropocene Working Group to start preparing a formal submission to, ultimately, the ICS. Two large publications, a special issue of The Philosophical Transactions of the Royal Society A and A Stratigraphical Basis for the Anthropocene, came first. Now this edited collection does what it says on the tin, providing the latest update on the evidence and the debate by summarizing a huge body of work.
The first chapter provides a short history of what I have sketched above and, for the reader not versed in stratigraphy, useful basic information on how stratigraphy works, past decisions on defining and naming geological periods, plus a very interesting and relevant section outlining why formal acceptance and definition of the Anthropocene matters. The bulk of the book consists of five chapters examining how humans have tangibly modified our planet, and whether this leaves stratigraphically suitable markers. Depending on your viewpoint, this could be taken as a catalogue of our atrocities or a celebration of our achievements.
The range of impacts covered is comprehensive and includes some eye-opening facts and frighteningly large numbers. We are leaving a stratigraphical legacy by changing natural patterns of sedimentation via erosion and river damming. We construct infrastructure and buildings above and below ground and create many novel types of “rocks” such as cement, asphalt, and concrete (so much so that we risk running out of suitable sand). But we also enrich soils and sediments with fly-ash and soot from burning fossil fuels. And this is before we even talk of the insane amounts of plastics that end up in our environment, now degrading into micro- and nanoplastics that are found everywhere. And then there are what Zalaziewicz and others have dubbed “technofossils”: all the objects that we discard in refuse tips, revealing a stratigraphy all of their own.
Less visible but no less influential are chemostratigraphical changes. That is to say, the release of carbon and methane from (again) fossil fuel burning, nitrogen and phosphorus from synthetic fertilisers, sulfur compounds, metals, organic (in the chemical sense) compounds such as pesticides and fire retardants (your POPs, PAHs, PCBs, PBDEs, etc.) and, lest we forget, radionuclides from atomic and hydrogen bombs. All these have left detectable accumulations in air, water (including ice), and soil. A biostratigraphical signature is detectable as both recent and ongoing extinctions (particularly the extinction of the Quaternary megafauna, though see my review of End of the Megafauna), the rapid spread of invasive species and domestic animals (with broiler chickens being one example of an expected future signal in the fossil record), and the fate of coral reefs. Finally, there is climate change, made visible in changes to ice cover and sea level.
What I casually summarise here in two paragraphs is presented in-depth, providing an overview of a huge body of research. And despite subchapters being contributed by many different authors, the overall flow and coherence of the text are good. Although not the first book to detail humanity’s planetary impact, the question of interest here is which of these would make suitable stratigraphic markers.
So what makes a good marker? Ideally one that is global in extent and that was laid down synchronously, i.e. very rapidly, so that the age of the marker is the same wherever measured. A volcanic ash layer is a good example, and so, of course, is the iridium spike signalling the meteorite impact at the K-Pg boundary.
Not all of the potential markers discussed in this book meet these criteria, even though they reveal humanity’s impact. So, the sudden appearance of so many new long-lasting rock-like compounds and plastics is a good marker. Another one is lead released during the burning of fossil fuels, which shows up in natural archives such as sediments, peat mires, and ice cores. (Plus, there is a precedent here: Greenland ice cores show a lead spike at the height of Greek-Phoenician and Roman mining). But the appearance of soils modified by human agriculture is an example of a signal that is too localised and too diachronous (the opposite of synchronous) to be of use. The same is true for the occurrence of stone tools, though modern technofossils such as broken iPhones could be useful.
A similar question is the when. Though some scientists favour the rise of agriculture ~10,000 years ago or the beginning of the Industrial Revolution in the late 1700s as the start of the Anthropocene, the editors here outline how a consensus is forming on the 1950s. This is when human population size boomed and many things basically went into overdrive. When plotted on graphs, many indicators considered here show a sharp upward inflexion right around this time.
As with other periods, it is highly likely that a combination of proxy signals will have to be used to define the Anthropocene – many natural archives are either sensitive to disturbance (lake sediments vs. burrowing animals), or record signals with a delay (e.g. isotope signals in stalagmites). For the moment this is all work in progress, and a formal submission to the ICS is still being prepared by the Anthropocene Working Group. Much like the closely-allied Intergovernmental Panel on Climate Change reports are the go-to books on climate change (also published by Cambridge University Press), this book is the most definitive and up-to-date reference work for anyone working on or interested in the geological case for the Anthropocene.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
The Anthropocene as a Geological Time Unit hardback
or ebook
Other recommended books mentioned in this review:
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]]>Like Antarctica, Greenland is one of those places that exerts an irresistible pull on my imagination. As journalist, historian and The New York Times Magazine feature writer Jon Gertner makes clear in The Ice at the End of the World, I am not alone. This solidly researched reportage chronicles both the early explorers venturing onto Greenland’s ice sheet and shows the reasons it plays a starring role in research on climate change. Some books ought to come with a warning about how binge-read-worthy they are. This is one of them.
The Ice at the End of the World: An Epic Journey Into Greenland’s Buried Past and Our Perilous Future, written by Jon Gertner, published in Europe by Icon Books in September 2019 (hardback, 421 pages)
Split into two parts, “Explorations” and “Investigations”, the book starts with what Gertner calls the waning days of the age of exploration. The names of those who tried to reach our planet’s poles have gone down in the annals of history, but the men who ventured onto Greenland’s ice sheet have largely been lost to memory: Norwegian explorer Fridtjof Nansen, the first European to trek across the ice sheet below the Arctic circle from East to West in 1888. The American Robert Peary, who made a gruelling round trip at Greenland’s northernmost end in 1891-92. The Greenland-born Dane Knud Rasmussen and Norwegian Peter Freuchen who explored the same area as Peary did some two decades later, but with an eye towards ethnographical research amongst the local Inuit.
Although these men were celebrities in their time, and, like Charles Darwin and Alfred Russel Wallace, wrote large books about their travels, I had not heard of them before. Some of their books were never translated into English, and there have been no biographies written about them in recent decades, if at all. Gertner has thus dug into original sources in libraries and research institutes to retell the stories of these men and the brave souls who joined them on their expeditions, for these journeys were not solitary affairs. These are amazing stories of brutal physical and mental hardships: freezing temperatures, fierce winds, snowblindness, crushing monotony and boredom, fingers and toes lost to frostbite, and sometimes death. But also stories of raw beauty and poetic rapture at the scale and grandeur of nature. Greenland does this to you, and Gertner gratefully mines their writings for inspiring words.
The only name that did ring a bell was Alfred Wegener, the German meteorologist and geophysicist who fathered the idea of continental drift. But that will be my fascination with the captivating history of the reluctant acceptance of his ideas , and the fact that there are recent biographies on him (see Ending in Ice and the exceptionally thorough Alfred Wegener). Gertner nimbly side-steps the continental drift story and maintains a tight focus on Wegener and Johan Peter Koch’s first ice sheet crossing in 1913, and Wegener’s later return to set up a research base in the middle of the Greenland ice sheet in the early 1930s. A successful undertaking for which he tragically paid with his life, freezing to death on a return trip.
From here, Gertner jumps forward in time a few decades. Whereas early expeditions had scientific aims, they were as much about exploration and often sheer survival, so early findings were both exploratory and limited. Gertner highlights the role of French explorer Paul-Émile Victor who brought his experience in the US Air Force, testing and developing survival equipment, to bear on polar research. As frequently happens, technology developed by the military often finds a second life in science. The development of more reliable heavy-duty motorised vehicles removed the need for death-defying expeditions by human or dog-pulled sledges. This was the start of the drilling of ice cores and saw the discipline of glaciology bloom.
A particularly eye-opening chapter is that of Thule Air Base that the US Department of Defense established in 1951 in northern Greenland at the start of the Cold War. This story was only touched upon in Cold Rush, but it explains America’s continued interest in Greenland. Trump has not been the first US president trying to purchase Greenland from Denmark. And it is a bizarre story. The sheer amount of manpower, material, and money that the US threw at this project was staggering. Victor cleverly piggy-backed on the army’s presence and funding to undertake scientific research. Their departure as the Cold War wound down complicated financing further research to understand Greenland’s role in climate change.
This second part of the book revolves primarily around the drilling for ice cores and the research that has allowed scientists to deduce past temperature, CO2 levels, and other palaeoclimatological variables. Gertner combines first-hand reportage during repeated visits to Greenland, numerous interviews, and careful reading of scientific papers to tell a thrilling narrative. Especially the shock discovery of evidence for abrupt climate change in the deep past takes centre-stage here. Initially, this was thought to be noise in the data, but then it was confirmed when subsequent ice cores showed the same signal, again and again.
Gertner does a good job here introducing the physical basis of climate change, the long history of research on it, and some of the technical details of methods currently in use (isotope analysis, mass spectrometry, remote sensing with satellites, and the gravimetric analyses by NASA’s GRACE mission). But what he makes especially clear is that there is nothing alarmist about climate scientists’ concerns regarding melting ice sheets, calving glaciers, and the threat of tipping points beyond which changes could rapidly accelerate.
Gertner has spent years on this book, and The Ice at the End of the World stands out for the depth and thoroughness of its research. The 300-page narrative maintains a tight focus on its subject. It is accompanied by 70 pages of often very interesting notes where Gertner acknowledges which diversions are beyond the scope of this book, a section called “further sources” including a long list of interviews conducted and oral histories consulted, and a selected bibliography. But above all, the book is gripping. The memorable cast of historical characters, the pioneering research under challenging circumstances, the unusual settings – it has resulted in a book that I just could not put down.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
The Ice at the End of the World paperback
, hardback or ebook
Other recommended books mentioned in this review:
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]]>“Cold Rush: The Astonishing True Story of the New Quest for the Polar North“, written by Martin Breum, published by I.B. Tauris in June 2018 (hardback, 252 pages)
Danish journalist Martin Breum has been reporting on the Arctic for the last decade, both at home and abroad, and Cold Rush is based on selected and updated chapters from previous Danish books. He provides an intimate reportage of the political wheeling and dealing behind the scenes as various nations start to lay claim to the Arctic, specifically focusing on Greenland and its fraught relationship with Denmark. (For those looking for a wider picture beyond Greenland, I would also recommend The Scramble for the Arctic: Ownership, Exploitation and Conflict in the Far North, The Future History of the Arctic: How Climate, Resources and Geopolitics are Reshaping the North, and Why it Matters to the World, and The Scramble for the Poles: The Geopolitics of the Arctic and Antarctic.)
Greenland is a bit of an enigma. Geographically part of the North American landmass, it is a former colony and now autonomous country of the Kingdom of Denmark, boosting that country’s surface area more than 50-fold. But with only 57,000 or so inhabitants, it remains firmly dependent on Denmark. Through a so-called block grant, Denmark supports the Greenland government with an annual 3.4 billion kroner (roughly 500 million US dollars) that pays for things such as pensions, hospitals, and schools. And Denmark contributes vessels, aircraft, and dog sledge teams that patrol the borders and waters year-round (Breum accompanies one such patrol and reports on that here). A final fun factoid I got from this book: the UK is not the first country to exit the EU, Greenland did so back in 1985! I wonder how many people are aware of this because in two years of Brexit circus I have not heard this mentioned once.
The period covered by Cold Rush is the last decade since 2007, during which there was a lot of geopolitical shenanigans in and around the Arctic. Russian submarines planted a flag on the seabed of the North Pole in 2007, with diplomats on all sides quickly downplaying this as “not-a-claim”. That, however, has not stopped Russia and Denmark from trying anyway (Canada is expected to follow suit in the near future). Attention has centred on the Lomonosov Ridge, a long, underwater mountain range. Whoever can prove this to be an extension of their continental shelf can try and claim it as territory by applying to the UN Commission on the Limits of the Continental Shelf. If granted, it would secure exploitation rights to whatever mineral and fossil fuel riches might be found there. Breum reports on one particular Danish research cruise he accompanied that was trying to determine whether the Lomonosov Ridge is an extension of Greenland’s bedrock. The findings resulted in Denmark claiming a large swathe of the seabed that overlaps with Russia’s earlier claim, setting the stage for tensions in the Arctic.
But is there anything of value out there? Results of seismic surveys so far are disappointing and Breum writes of the 2014 report by geologist Minik Rosing that warned of unfounded optimism regarding fuel and mineral reserves. Even so, governments are not taking risks and tensions rose when Denmark, Norway, Russia, Canada, and the US signed the Ilulissat Declaration, encouraging cooperation and the protection of their mutual Arctic interests, effectively locking the rest of the world out of further negotiations. This, of course, much to the chagrin of other countries who see this as a Machiavellian attempt to not share the Arctic pie (see also Contesting the Arctic: Politics and Imaginaries in the Circumpolar North).
Especially China is keen to shoulder its way in, which, as Breum makes clear, has more to do with mineral riches than fossil fuel. The retreating Greenland glaciers are expected to expose new mineral beds and China is particularly interested in rare earth elements, so vital in modern electronics that they produce and export in abundance. Countries are lining up to sign mining licenses, and there is much debate inside and outside of Greenland whether or not to let foreign companies in. One particularly sensitive topic is uranium ore, as Denmark is adamant that none of it is used in the production of nuclear weapons. But Greenland wants to have the final say in this matter and, worryingly, parliament abolished a national ban on uranium mining in 2014.
This last is symptomatic of the final major theme of this reportage: independence. There are influential voices in Greenland pushing for full independence from Denmark and Breum provides an intimate picture based on interviews with prominent politicians. Denmark is keen to keep its ties to Greenland as it stands much to lose. But even in Greenland the topic is divisive. Many hope that developing Greenland into a mining nation will wean it off the financial life support provided by Denmark. Opening up the country to foreign investors would be a logical first step. Others argue financial independence is decades away and are worried that, meanwhile, Greenland’s small population will be overrun by foreign labourers.
One thing seems for sure, there is little interest in turning Greenland into a nature reserve. Politicians argue that Greenland has every right to exploit its natural wealth – nature be damned. After all, is this not what every other nation has done so far? And this brings me to what seems like a curious omission. Although Breum seems well aware of the looming environmental problems, climate change never comes up in conversation, merely hovering in the background as the spectre yielding new opportunities. Greenpeace and environmental activism are mentioned a few times, but beyond that, all we hear are political platitudes about the desire to balance natural resource extraction with environmental protection. I cannot tell whether everyone is completely preoccupied with the promise of new riches, or whether Breum has decided to make this his exclusive focus.
The reporting in Cold Rush is thorough and impartial – where politics is concerned Breum speaks to parties pro and contra matters such as foreign investment, Greenland’s push for independence, etc. But he refrains from any personal reflection, merely acting as a dispassionate observer. Despite some of the source material having been published in various forms previously, the chapters have been rewritten such that the book flows well and does not unnecessarily repeat information. The result is a revealing and very informative insider’s account of the geopolitical manoeuvring in the Arctic. Highly recommended to be read alongside Brave New Arctic: The Untold Story of the Melting North, which will fill you in on the climatological details.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
Other recommended books mentioned in this review:
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]]>These three tasks, so says nature writer Robert Macfarlane, signify our relationship with the world beneath our feet, both across time and across cultures. Underland is his lyrical exploration of underground spaces where people have sought shelter from warfare or hidden valuable treasures, are extracting minerals in mines or knowledge in research facilities, or are looking to dispose of waste. It is one of two big books published only five months apart on the subterranean realm, the other being Will Hunt’s Underground: A Human History of the Worlds Beneath Our Feet which I will be reviewing next. But first, Underland.
“Underland: A Deep Time Journey“, written by Robert Macfarlane, published in Europe by Hamish Hamilton in May 2019 (hardback, 496 pages)
For those who don’t know him, Macfarlane has been writing about “the relationship between landscape and the human heart”, bagging several literary prizes along the way. For him, Underland is a conclusion to a personal story-arc of exploration that started up high with his fascination with mountains (see Mountains Of The Mind: A History Of A Fascination) and descended from there (see his books The Wild Places, The Old Ways: A Journey on Foot, and Holloway). The book is based on more than a decade of exploration, usually in the company of experienced locals.
Think underground, and you will likely think caves, and there is plenty of caving here. Macfarlane takes the reader into the underground river Timavo in Italy, a starless river that speleologists have been exploring and mapping for decades. He is guided into the karst landscapes of the Slovenian highlands that hide a chilling legacy of ethnic cleansing dating to the second World War, when corpses were dumped down sinkholes by the thousands. He explores cave chambers in Norway’s Lofoten archipelago, whose cave paintings make it the Lascaux of the high North. And he traverses, and descends into, glaciers in Greenland. But he also ponders realms not accessible to us, such as the “wood wide web”, the symbiosis between tree roots and soil fungi. This might allow trees to exchange information with each other, even crossing species boundaries. The idea of this “underground social network” has been popularised by Peter Wohlleben in The Hidden Life of Trees: What They Feel, How They Communicate – Discoveries from a Secret World.
But equally fascinating are the human subterranean landscapes he enters: prehistoric barrows (cemeteries) in Somerset, and a modern rock-salt mine in Yorkshire where excavated chambers double up as laboratories for physicists probing the universe for dark matter. He joins urban explorers, so-called cataphiles, in Paris and London who roam the crypts, catacombs, wells, bunkers, tunnels, and drains under these cities, “shadow twins to the upper world” (see e.g. Global Undergrounds: Exploring Cities Within or Subterranean London: Cracking the Capital). And he gets a tour around the subterranean waste facility in Olkiluoto in south-west Finland, currently under construction, which will store highly radioactive spent uranium fuel rods for 100,000 years. A feat which brings with it a whole new suite of considerations – how do you warn the species of the future to stay away?
What make these 400+ pages of caving, crawling, and occasional claustrophobia such a joy to read are Macfarlane’s evocative descriptions. Here is a word-smith at work, who can go from profound (“To these subatomic particles, we are the ghosts and ours the shadow-world, made at most of a diaphanous webwork”) to funny (“If you wish to listen for sounds so faint they may not exist at all, you can’t have someone playing the drums in your ear”) with but a flourish of his pen. The things he has seen have etched themselves into his memory, and he is intent on burning them into the memory of his readers in turn. From the majestic and rarely witnessed calving of a Greenland glacier (“a blue cathedral of ice, complete with towers and buttresses, all of them joined together into a single unnatural side-ways collapsing edifice”), to the surreal dumping ground in mid-Wales where locals have been pushing car wrecks down an abandoned mine shaft (“The result was an avalanche of vehicles […] a slewing slope of wrecks”). There are some truly memorable passages in this book.
Two themes run through this book, one already hinted at in the book’s subtitle. The first is that of Deep Time; the vast stretches of time in which geologists think when describing the evolution of our planet (see e.g. The Planet in a Pebble: A Journey into Earth’s Deep History). “Ice breathes. Rock has tides. Mountains ebb and flow. Stone pulses. We live on a restless Earth”, writes Macfarlane. Whether it is caves that have been hollowed out by the lapping of the sea over milennia, or the palaeoclimatological archive that we are retrieving from glacial ice cores (see The Two-Mile Time Machine: Ice Cores, Abrupt Climate Change and Our Future), going underground brings into focus the steady grind of our planet. Although a human lifespan pales into insignificance, Macfarlane resists apathy. Much like Bjornerud (see my review of Timefulness: How Thinking Like a Geologist Can Help Save the World), Macfarlane hopes that “deep time awareness might help us see ourselves as a part of a web of gift, inheritance and legacy stretching over millions of years”.
Tying in with this is the theme of the Anthropocene, the newly proposed geological epoch based on the detritus that humanity is leaving in the rock record (see my review of The Anthropocene as a Geological Time Unit). Like others before him, such as Alan Weisman in The World Without Us or Jan Zalasiewicz in The Earth After Us: What Legacy Will Humans Leave in the Rocks?, Macfarlane asks what legacy we are leaving behind. Nuclear waste is obviously one of the longest-lasting, but there are other revelations in this book. I was, perhaps naively, shocked to read of the mining company that simply abandons worn-out excavators, which cost £3.2 million, underground.
Each chapter opens with a black-and-white photo or illustration. I woul have loved to see more images, perhaps a colour plate section, as there are some striking photos included in this BBC interview. A book of this calibre leans on poetic language to a certain degree, but nowhere did I find Macfarlane self-indulgent or flowery. On the contrary, the book provides its own beautiful raison d’être during an interview with plant scientist Merlin Sheldrake. Macfarlane ponders how to make sense of the implications of the symbiotic interaction between fungi and trees: “Perhaps we need an entirely new language system to talk about fungi… We need to speak in spores.” To which Sheldrake enthusiastically replies: “That’s exactly what we need to be doing – and that’s your job […] the job of writers and artists and poets and all the rest of you”. I couldn’t have said it better myself.
So, how does Macfarlane’s Underland compare to Hunt’s Underground? It feels Macfarlane casts his mind outwards more, pondering deep time and the Anthropocene, while Hunt turns his gaze inwards, probing the more human side: religion, spirituality, and neurobiology. Macfarlane, as a nature writer, is more poetic in his writing, though Hunt, using a different tone, is an equally masterful storyteller. Underland is carefully annotated and referenced, but barely illustrated – Underground is the reverse. And even though both writers end up exploring under Paris and both touch on topics of biology and archaeology, it is striking how little they overlap. Clearly, the world under our feet is so vast there is space for more than one book. Why pick one? I heartily recommend them both!
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
Underland paperback
, hardback, ebook, audiobook or audio CD
Other recommended books mentioned in this review:
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]]>“The Uninhabitable Earth: A Story of the Future“, written by David Wallace-Wells, published in Europe by Allen Lane in February 2019 (hardback, 310 pages)
The Uninhabitable Earth expands on the essay published in New York magazine in July 2017. The piece quickly attracted criticism from climate scientists for being rather cavalier with its facts. Amidst the many responses, a useful summary is the piece published by science education NGO Climate Feedback in which 17 prominent climate scientists evaluated the essay. To its credit, New York magazine was quick to publish an annotated edition.
The near future sketched in the first half of The Uninhabitable Earth is one of a planet tortured by epic wildfires, rising sea levels, megadroughts, famines, acidifying oceans, polluted air, and rising temperatures amidst which hundreds of millions of climate refugees wander a planet in the throes of collapsing economies and emerging conflicts. In short, Wallace-Wells would like you to know that, unless urgent action is undertaken to combat climate change, we are all royally fucked.
He is not the first to sound a desperate alarm, and his book joins a budding subgenre that some critics disparagingly label “climate porn”. James Hansen, the well-known climate scientist who has chastised colleagues for not speaking up out of fear of being labeled alarmist, has done so before (see Storms of my Grandchildren: The Truth about the Coming Climate Catastrophe and Our Last Chance to Save Humanity), while others have declared the fight over (see Too Late: How We Lost the Battle with Climate Change or Reason in a Dark Time: Why the Struggle Against Climate Change Failed – and What It Means for Our Future). Some climate scientists are annoyed by what they perceive as scaremongering, arguing that frightening people will result in fatalism rather than galvanizing them. I guess people will respond in different ways, and recent climate protests suggest that his approach certainly works for some. Either way, Wallace-Wells does not mind being called alarmist, his (touché) defence is that he is alarmed, and you should be too.
Now, Wallace-Wells openly states he calls on predictions, on science that is in flux as new findings come to light. Even if he gets some of the details wrong, the overall pattern is pretty clear. As I have written elsewhere (see my reviews of The Ends of the World: Volcanic Apocalypses, Lethal Oceans and Our Quest to Understand Earth’s Past Mass Extinctions and The Oceans: A Deep History), the findings from palaeoclimatology leave little doubt as to what happens when you keep pumping carbon dioxide and other greenhouse gases into the atmosphere.
The author brings together many poignant observations. Global warming is not a moral and economic debt that has been accumulating since the Industrial Revolution – about half of all fossil fuels have been burned in only the last three decades. And our epoch could very well be a blip on the timeline, the result of a gigantic one-off injection of fossil fuel into our economy, allowing us to live in a temporary mirage of “endless and on-demand abundance for the world’s wealthy” (I told you he was poetic).
The Uninhabitable Earth is not a book of solutions though, and Wallace-Wells spends a good part of the second half of the book railing against what he thinks will not work. Against the hallucinatory fantasies of Silicon Valley who hope to escape into a virtual reality, uploading their consciousness into computers. Against as-of-yet hypothetical technofixes such as carbon capture and storage or negative emissions technology. Against ecological nihilism by burned-out environmentalists such as Paul Kingsnorth (see Confessions of a Recovering Environmentalist). If you want practical advice, you are better off reading There Is No Planet B: A Handbook for the Make or Break Years.
The Dutchman in me can appreciate his in-your-face polemic style. This is why I am surprised he overlooks one vital aspect: overpopulation. As soon as this topic comes up, Wallace-Wells seems blindsided. Part of him is excited for his daughter and the world she will inhabit, one which will be “doing battle with a genuinely existential threat”. This seems mildly perverse given the litany of terrors he lays out in this book. And those who abstain from having children over their concerns for a world ravaged by climate change “demonstrate a strain of strange ascetic pride”.
One problem I have with this line of argumentation, that our lifestyle and economy are wrecking the planet, is that it ignores numbers. Yes, our ancestors were not despoiling the planet, but I would argue it was not for want of trying, but for want of numbers. Now, I have no data to back this assertion up with, so I am going out on a limb here, but how much damage do you think a population of 7 billion stone age hunter-gatherers would have inflicted on the planet? Or 7 billion people trying their hand at farming some ten thousand years ago? I would not at all be surprised that if you work out the numbers, the reason our ancestors did not bring about climate change has more to do with their lack of numbers than with a lack of impact of their lifestyle.
And Wallace-Wells comes so close when he observes that most emissions have only happened in the last three decades. Could it be that the doubling of our world population has something to do with this? For a book that prides itself on its fierce frankness, not addressing overpopulation feels like a serious omission. It is a thorny topic (see my review of Should We Control World Population?), but if you want to talk solutions, addressing it should be a vital part of a multi-pronged approach he envisions to avoid the bleak future sketched here.
The Uninhabitable Earth is lyrical and stirring, but also controversial and not without its flaws. Is taking the predictions of climate change impacts to their logical extremes a valuable exercise? I am left feeling conflicted. I can sympathise with the urge to want to grab people by the scruff of the neck, but whether it ultimately is constructive is something I am not fully convinced of.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however. This review has been slightly edited since its publication to emphasize that I consider the author frank rather than alarmist.
The Uninhabitable Earth paperback
, hardback, ebook or audiobook
Other recommended books mentioned in this review:
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]]>“Liquid: The Delightful and Dangerous Substances That Flow Through Our Lives“, written by Mark Miodownik, published in Europe by Viking in September 2018 (hardback, 276 pages)
Narrated as one man’s thoughts and reflections during a transatlantic flight from London to San Francisco, Miodownik dwells on a range of interesting properties of liquids. The book opens with a canned history of liquid fuels, from wax, olive oil, and whale blubber, to modern hydrocarbon fuels such as kerosene. A related class of molecules, on the other hand, will get you drunk (see more in my next review of The Drunken Monkey: Why We Drink and Abuse Alcohol). Wine (see also A Natural History of Wine and The Science of Wine: From Vine to Glass) is steeped in mythology, some of it grounded in reality (the temperature at which you serve it), while other parts are delusional (the discerning abilities of wine tasting experts).
How do glues work? Why can Post-It notes be reused, while superglue binds things almost irreversibly? (And, wait, we glue aeroplanes together??). The magic worked by liquid crystal displays (better known as LCDs), the grossness of bodily fluids (except when we’re kissing), or a very British jaunt into the particulars of what makes the perfect cup of tea, Miodownik touches on all sorts of topics. Liquids allow us to clean ourselves, refrigerate food, and write. Especially the history of László Biró’s pen, the biro or ballpoint pen, is very interesting (see also Ballpoint: A Tale of Genius and Grit, Perilous Times, and the Invention that Changed the Way We Write).
But liquids and liquid-like properties also play a role on a planetary scale, in fields such as meteorology (cloud formation), oceanography (waves and tsunamis), or structural geology and plate tectonics (earthquakes, volcanoes, and mountain building). While Miodownik talks of the delights of catching the perfect wave when surfing (see also The Wave: In Pursuit of the Oceans’ Greatest Furies), other topics such as rogue waves (see Rogue Waves: Anatomy of a Monster), tides (see Tide: The Science and Lore of the Greatest Force on Earth), or ocean currents (see The Great Ocean Conveyor: Discovering the Trigger for Abrupt Climate Change) are not mentioned.
The thing is, there are many stories that could be told here, but Liquid is not intended to be an exhaustive treatment. Miodownik instead uses his narrative structure to focus on the liquids we encounter in our daily lives and spins off his tales from there. Little hand-scribbled drawings highlight how the different properties are a function of the molecular structure of a liquid. There is also a selection of black-and-white photos, although their reproduction and size sometimes had me look twice to figure out what I was seeing.
And then there is Susan, a fellow passenger who has to suffer Miodownik’s zaniness and social awkwardness. This element might feel slightly forced, although some of the situations he recounts are embarrassingly familiar (falling asleep on a fellow passenger?). As he later reveals, it’s a shame they never got talking during the flight.
All in all, Liquid is popular science of a high level, avoiding factoid lists and the hysterical “OMG, did you know?!!” tone. Instead, Miodownik knows how to spin a fine yarn and his writing is amusing without being silly, informative without being patronising. He proves himself the teacher we all would have wished for in our high school chemistry and physics classes.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
Liquid hardback
, paperback, ebook or audiobook
Other recommended books mentioned in this review:
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]]>“The Curious Life of Krill: A Conservation Story from the Bottom of the World“, written by Stephen Nicol, published by Island Press in July 2018 (hardback, 194 pages)
Krill are so much more than just delectable food items for the largest filter feeders on the planet. Stephen Nicol is one of the world’s foremost krill scientists and based on his four decades studying them, he here tells the story of the Antarctic krill, Euphausia superba, the largest and best-known species.
In a pithy book of less than 200 pages, Nicol describes what we know of their biology. Since studying anything in the Antarctic is exceedingly difficult and costly, we do not know that much compared to some of the more charismatic megafauna such as whales, seals, or penguins that live at the bottom of the planet. What we have learned so far reveals a fascinating animal that might be one of the most abundant multicellular animals on the planet (though I have heard that claimed of lanternfish, see Deep-Sea Fishes: Biology, Diversity, Ecology and Fisheries) that migrates vast distances in the water column. We are not quite sure how old they get – one trick they have up one of their many sleeves is that they can grow smaller during food shortages, making size an unreliable measure of age. And during winter, young krill inhabit an upside-down winter wonderland just underneath the sea-ice, grazing on algae growing in the crevices of ice floes.
Krill hold an unusual position in the Antarctic food web, not quite at the bottom but somewhere in the middle, in what ecologists apparently call a wasp-waist ecosystem. This is to say that all energy that passes up the food chain has to pass through krill. Scientists and fishermen long thought that the wholesale slaughter and near extinction of whales might have resulted in a population explosion of krill, their main predator now having been removed. But, as also related in Serendipity: An Ecologist’s Quest to Understand Nature, ecosystems are complex and marine ones are perhaps even harder to gauge for us landlubbers. Instead, research suggests that whales are responsible for rapidly cycling iron through ocean ecosystems. This is a limiting nutrient for plankton, especially in the Antarctic, where the ice-smothered continent leaches virtually nothing into the ocean. Krill retain a lot of iron, but whales expel most of it when they eat krill. Removing whales from the ecosystem has reduced the flux of iron, inhibiting phytoplankton growth, leaving less food for krill. As I already mentioned in my review of Spying on Whales: The Past, Present and Future of the World’s Largest Animals, whaling has in that sense impoverished the seas in ways we did not even imagine (see also Whales, Whaling, and Ocean Ecosystems).
Luckily, The Curious Life of Krill is far from a gee-whiz collection of facts as I enumerate above. Nicol’s writing on his favourite crustacean reveals much about the hardships of biological fieldwork, the technologies employed, and the care needed when interpreting and extrapolating data. Furthermore, after retiring in 2011, he enrolled in a master’s degree programme in creative writing, and I dare say that that shows. The book is very readable, and effortlessly mixes history and personal anecdotes in an amusing way that never comes across as forced. The chapters where this really shows is where he discusses fisheries management.
Next to his work as a scientist, Nicol has been involved with the international commission that manages Antarctic fisheries. Unbeknownst to many, the Antarctic has seen many failed attempts at developing an intensive krill fishery. Now, overfishing is an important topic, but it can make for turgid reading (see my review of All the Boats on the Ocean: How Government Subsidies Led to Global Overfishing). Not so Nicol; he provides a frankly fascinating bunch of chapters on these failed attempts and on the international commission that has brought all relevant countries to the table to make sure exploitation of this fishery proceeds in a sustainable manner. Remarkably, they have so far been successful, although one has to wonder if that has more to do with the difficulties of making this an economic success story. As of yet, there is little market for krill and krill products, and the efforts required to catch sufficient krill are incredibly costly in this hostile environment.
The Curious Life of Krill is a captivating little book, and also the only book for laymen (the only other recent book I’m aware of is the scholarly edited collection Biology and Ecology of Antarctic Krill). Nicol does a superb job of distilling crustacean biology, hard-won personal experience, and interesting history into a book that never gets a chance to outstay its welcome. If you have even the slightest interest in books on oceanography, marine ecosystems, or the many interesting creatures that live here you should most certainly add this book to your reading list.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
The Curious Life of Krill hardback
or ebook
Other recommended books mentioned in this review:
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]]>“Brave New Arctic: The Untold Story of the Melting North“, written by Mark C. Serrezek, published by Princeton University Press in May 2018 (hardback, 248 pages)
This book is part of Princeton’s Science Essentials series, which aims to inform a general audience of rapid changes in a scientific field, told in a clear manner by a prominent expert in that field. Brave New Arctic is such a smooth read that, like a Greenland glacier sliding off its bedrock due to the Zwally effect (more about that in this book), I raced through it in a mere five hours.
Starting his narrative in 1982, when he first got involved in Arctic field research as a young cub scientist, Serreze talks us through his own research over the years, as well as the findings of the wider research community. Especially his early research, which involved a lot of work out in the Arctic, is spiced up with personal anecdotes of colourful characters and adventurous conditions out on the ice. It takes a certain character to brave these cold conditions.
As I already mentioned in my review of The Oceans: A Deep History, the Earth system is fiendishly complex. However, Serreze skillfully narrates the complexities of climate science in the Arctic. And there are an awful lot of variables that can interact with each other in feedback loops: sea-ice extent, ice thickness, near-surface air temperatures, permafrost thawing, melting processes of glaciers, circulation of ocean currents, thermal stratification of both atmosphere and water layers in the ocean, reflectivity of earth’s surface to sunlight (albedo)… it is a lot to take in. Much to his credit, every time I found myself thinking “I understand what he’s saying, but an illustration would be helpful”, I turned the page to find a map or drawing explaining key mechanisms or findings.
Unsurprisingly, as Serreze tells, the first few decades were spent in general confusion as scientists gathered data from many different sources and tried to make sense of it all. A further complication is that, yes, there are large natural cycles playing out over decades. The discovery of one such cycle, the Arctic Oscillation, is vividly described here. These make it difficult to say that climatic changes you observe are definitely due to human input. But as time passed and these natural cycles went into a phase of retreat, normally leading to a cooling Arctic, the Arctic kept on warming, with the early 2000s seeing new record-lows in the amount of remaining sea ice year upon year.
Somewhere during this time, palaeoclimatologists also got in on the research, and their combined efforts have provided a picture of Earth’s climate going back millennia. Obviously, since no written records go back this far in time, they rely on so-called proxies such as measurements on ice cores. Alley’s book The Two-Mile Time Machine: Ice Cores, Abrupt Climate Change and Our Future provides a very well-written introduction to the study of ice cores.
The reason I bring up Alley here is that the dustjacket of Brave New Arctic features an endorsement by him that mentions Serreze’s conversion from a true sceptic to someone who accepted that humans are to blame for observed climatic changes. I just want to make the important distinction here between denialists (sticking your head in the sand) and sceptics (proper scientific conduct). Serreze belongs to the latter category. As he openly describes, despite theoretical expectations and model predictions saying that human influence will become apparent, it was initially hard to say for sure what was causing the observed changes in all of the above-mentioned variables. Natural fluctuation or human influence? For a while, the former was masking the latter. But by the early 2000s climatic changes were becoming so extreme, and so far outside of the historical values that palaeoclimatologists had described, that even Serreze became convinced that our impact on the Arctic was becoming clearly visible.
Another thing that has bedevilled our understanding are the patchy records. Climate scientists initially had only short-term, local datasets to work with. The other major strand of the story that Serreze weaves into this book is how the research community came together, and through an ever-shifting array of international collaborations (with ever-shifting acronyms) is now gathering datasets that are more comprehensive in both their duration and spatial coverage. This depends on continued financial support by funding agencies and therefore governments, so Serreze includes the influence of politics and how it has taken an unfortunate turn in the last decade, ranging from science being ignored to being flat-out suppressed. A lot more has been written about this in books such as Powell’s The Inquisition of Climate Science and Mann’s The Hockey Stick and the Climate Wars: Dispatches from the Front Lines. Serreze is also not afraid to highlight how science remains a human endeavour and as such suffers from internal strife, competition, vanity, etc. Even so, the scientific process at large works, and it keeps on improving our understanding of what is happening.
Serreze masterfully explains how we now understand many things. New frontiers remain, and especially the threat of thawing permafrost, the release of methane from underwater deposits, and the melting of the Greenland ice sheet are areas where many uncertainties remain. Remember though, it is not a matter of “if”, but “when” – or rather “how soon”. It is perhaps too much to expect Serreze to provide solutions (writes this reviewer, as he mutters “addressing overpopulation, anyone?” under his breath), and Serreze rarely mentions the human dimension of this story, such as the impact on indigenous people in the Arctic. However, just the process of figuring out the complexities of climate change is enough to occupy the lifetime of a legion of scientists. Like Weart’s book The Discovery of Global Warming, Serreze provides an arresting account of the history of climate science, written by someone who saw it all unfold before his own eyes. If you thought you had heard it all, think again, and read this book.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however.
Brave New Arctic paperback
, hardback, ebook, audiobook or MP3 CD
Other recommended books mentioned in this review:
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]]>“The Oceans: A Deep History“, written by Eelco J. Rohling, published by Princeton University Press in January 2018 (hardback, 262 pages)
I will come right out and say that I found this book a challenging read. Partly this is because my background is not in geochemistry, and there is quite a bit of that here, partly this is because, whether you like it or not, the Earth system is complex. Fiendishly complex. Trying to put into words the many interlocking feedback mechanisms playing out on different timescales will, therefore, make for dense reading in places.
The Oceans starts off with three introductory chapters that are quite technical, featuring a lot of oceanographic, geochemical, and atmospheric chemistry details necessary to understand the rest of the book. There are a number of helpful illustrations in this section that the reader will be referred to time and again. It is not until page 83 that Rohling starts his journey through the deep history of our oceans. To structure the book, he has chosen three key topics important to our understanding of past and current climate fluctuations.
The first thing most people will think of when you mention climate change is temperature, and Rohling walks the reader through reconstructions of Earth’s thermal record. There were times where our planet was frozen solid (periods appropriately known as Snowball Earth), such as the Huronian glaciation between 2.4 and 2.1 billion years ago, and more “recently” in the Neoproterozoic Era between 750 and 580 million years ago. The latter was followed shortly by the famous Cambrian explosion, an episode in Earth’s history where life flourished. During the reign of the dinosaurs, the world has been much hotter, with average temperatures some to 10°C to 15°C higher than they are today. This chapter is a good example of the challenge of putting into words the complex interplay between the organic and inorganic carbon cycles, as fluctuations in atmospheric carbon levels are responsible for these long-term temperature swings.
The second topic, of much relevance today as well, is ocean acidification. As Rohling explains throughout the book, the oceans are an enormous buffer for carbon. But just as the oceans aren’t a featureless bathtub (see the introduction to Deep-Sea Fishes: Biology, Diversity, Ecology and Fisheries for a good overview of ocean topography), they are also not a chemically inert bathtub. Levels of dissolved carbon dioxide change the acidity of water, which affects shell-bearing organisms large and small. One episode where strong ocean acidification is implied is the end-Permian mass extinction some 252 million years ago, which was so vividly described in Brannen’s book The Ends of The World: Volcanic Apocalypses, Lethal Oceans and Our Quest to Understand Earth’s Past Mass Extinctions, and is the subject of Benton’s When Life Nearly Died: The Greatest Mass Extinction of All Time. A more recent, and therefore better documented, episode was the Paleocene-Eocene Thermal Maximum some 56 million years ago. During both these events, large amounts of carbon dioxide were released relatively quickly (several tens to hundreds of thousands of years is quick geologically speaking), leading to drops in oceanic acidity. The Ammonoids, the now-extinct group of cephalopods that we met in Staaf’s Monarchs of the Sea, was one group that was heavily hit during the end-Permian extinction episode.
The final topic that is hugely influential for life is water’s oxygen content. Lack of oxygen in water is also known as anoxia. Ocean Anoxic Events are periods of prolonged (hundreds of thousands of years) and widespread (possibly global) lack of oxygen. This, too, has relevance today as water pollution is once again leading to persistent “dead zones“; regions of the deep sea that remain devoid of oxygen for months or years at a time, choking most life forms to death. Ironically, the layers of putrefying organic material that build up during these historic Ocean Anoxic Events were slowly transformed into black shales, of much interest to the fossil fuel industry today.
Throughout the book, Rohling in passing mentions the important messages deep history has for our current times, but a book like this of course has to have a chapter explicitly dealing with current climate change. Looking at deep history, what makes the last 200 years different is not necessarily the amount of carbon we have so far released through the burning of fossil fuels, it is the speed. Conditions on our planet are changing faster than any time before, based on our reconstructions from Earth’s deep history, with the rate of change rivalling or exceeding even that seen during the end-Permian mass extinction. The two hundred years since the Industrial Revolution may seem like ages to humans, but they are a blip in deep history. Our inability to conceptualise deep time is a huge problem, something that is discussed in-depth in Bjornerud’s book Timefulness: How Thinking Like a Geologist Can Help Save the World.
And that is where this book shines. By surveying what the palaeoclimatological record reveals, by describing all the feedback mechanisms we have uncovered, it becomes abundantly clear that denying that current climate change is happening is absurd. Denialists both love to argue the quantitative details and grossly simplify them. Why can we not predict how much sea levels will rise exactly? Why is it not getting hotter everywhere? And yes, the finer details and timing of what awaits us are subject to a certain amount of uncertainty and are based on forecasts and modelling studies, subject to revision (guys, for f**** sake, this is how science works). But by attacking the quantitative details they are missing the bigger picture. Qualitatively speaking none of the changes that are forecasted are based on conjecture: Earth’s deep history, as explained here so in-depth, tells us what happens when our atmosphere and oceans change. People want to shrug this off and say “but the planet recovered, right? We are here today!” But this again painfully highlights our inability to conceptualise deep time. The natural geochemical processes that can undo rising temperatures or increased ocean acidity play out over hundreds of thousands of years. So, yes, the planet will recover from us, but we will not like the ride there.
The Oceans, then, is a book with many relevant lessons to understanding climate change today. Whether the dense material will reach the people who need to see it most is something I am doubtful of. But if you want to understand how our oceans work, and how they have influenced life as we know it, this book is mandatory reading that thoroughly covers the subject. Be prepared to engage your brain while reading it though.
Disclosure: The publisher provided a review copy of this book. The opinion expressed here is my own, however. You can support this blog using below affiliate links, as an Amazon Associate I earn from qualifying purchases:
Rohling’s The Oceans paperback
, hardback or ebook
Other recommended books mentioned in this review:
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