How Did the Climate Affect Our Ancestors?

The Atlantic

How Did the Climate Affect Our Ancestors?

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In his sweeping new book, Peter Frankopan looks at how the climate has changed human societyand how we have changed the climate. D oes climate change directly influence the weather we experience? Until recentlyfor the past 40 years or sothat question has followed nearly every major hurricane or flood, every record snowfall or heat wave. In some people, it provokes instant denial, often political or economic, often rooted in prideful ignorance. But the question raises a genuine analytical issue: How do we determine the effect of incremental, global atmospheric change on locally transient weather systems? And how do we assess the effect that those systemsand the climate shifts underlying themhave had on human societies in the past? These are complicated questions. Now imagine trying to answer them throughout the whole of history, from the origin of our species to the day before yesterday. Thats the task the Oxford historian Peter Frankopan undertakes in The Earth Transformed: An Untold History . Consider, for instance, what has come to be called the Little Ice Age, a period of sharply lower temperatures from (roughly) the 16th to the early 19th centuries. The term first appeared in 1939 in a report from the glaciers committee at the American Geophysical Union, and, as Frankopan notes, it became popular with historians and general readers alike. But was the Little Ice Age real? The idea of a prolonged era of sustained colder weather has evoked a kind of climate determinism, a tendency to blame human behavior in, say, the 17th century mainly on the temperature. The Little Ice Age has been used to explain any number of things: a sudden abundance of melancholy, the growing popularity of beer, the shift from open fireplaces to tiled stoves in Sweden, more clouds and darkness in paintings from the period, an astonishing increase in the persecution of women, even the gales that destroyed the Spanish Armada. Frankopan acknowledges that this period was a time of profound social, economic, political and ecological change. But an abundance of data indicates that there was nothing climatically coherent or globally synchronous going onnothing remotely like an ice age, not even a little one. The conclusion, drawn from marine-core data, sea-ice incidence and ice-core isotope records, is that theres almost no evidence for a climatically distinct and clearly cooler Little Ice Age. On this, Frankopan, many climatologists, and the Intergovernmental Panel on Climate Change agree. The very idea of a sudden, global, uniform, and extended cold spell also goes against common sense. The Little Ice Age is supposed to have lasted several centuries. But, as Frankopan reminds us, we wont discern any consistency across either time or space in a period that long. This can be hard to remember. The best corrective to denial and determinism is accurate climate data. The more we have, the better we can assess the pattern and scale of past climatic variations and their effects. As Frankopan routinely notes in The Earth Transformed , climate contributes as often as it causes . Famine in seventh-century China, for example, was begun by drought but worsened by inept rulers, a pattern repeated again and again throughout history. Even where connections seem both plausible and compelling, Frankopan writes, identifying the precise relationship between environmental and societal changes requires caution. He refuses to generalize beyond the evidence and is scrupulousalmost testyabout the quality of the evidence he uses. (My favorite demurrer: if data that is geographically and chronologically uneven is to be believed.) From time to time, Frankopan may sound as though hes debunking the argument that climate has helped determine the shape of human history. But hes really refining it, giving it greater authority based on better evidence. The question is no longer whether climate change can influence the scale and force of an individual hurricane or typhoon. Of course it can. We see it happening as storms intensify all around us. Global warming is affecting nearly every Earth system, including polar-ice conditions, monsoon cycles, ocean temperature, and the dynamics of the major ocean currents and oscillations. Its bringing an end to what the poet Marianne Moore once called the unegoistic action of the glaciers. What use is history in this context? What is there to learn from episodes of the distant past, such as the 15th-century Famine of One Rabbit in what is now Mexico and the sixth-century floods described by Gregory of Tours? Read: The way we talk about nature is getting weirder Frankopans purpose in The Earth Transformed isnt to explain how we find ourselves where we are climatically or to chronicle the steady increase of atmospheric carbon and our failure to curtail it. The book is doing something different. Frankopan presents an enormous panoply of cultures and societies affected by widely differing climatic pressures. He uses a wealth of new climate data and huge advances in climate modeling to understand the role that climate has played in shaping the history of the world, to retell history as if it were something more than the interactions of humans on a weather-less planet. Here are two examples. Around the year 540, a major cluster of volcanic eruptions shrouded the Earth in dust, dimming the sun, causing temperatures to plummet, and decimating human populations. (One expert called these the coldest decades in the Holocene.) Seven hundred years later, in the early 13th century, Mongolia experienced the wettest conditions in more than 1,000 years. Extra moisture increased pasturage and allowed enormous increases in the size of livestock herds, above all of horses. On those horses and their progeny, Ghengis Khan and his hordes were mounted. One of these events is global; the other isnt. Its worth noting that neither contributed to a steadily worsening set of interactive environmental conditions of the kind that threaten us now. Neither was part of an intensifying feedback loop like the one were living in, which is continuous, cumulative, and global. A t the very least, its chastening to see how other humans in other times responded to the dynamic Earth systems in which their lives were embedded, chastening too to see how often climatic events tyrannized daily existence. But what can those episodes tell us about how we should respond to our likely fate? Here is how Frankopan explains the rationale behind The Earth Transformed : As a historian, I know that the best way to address complex problems is to look back in time. History, he adds, can also teach valuable lessons that help formulate questions and sometimes even answers relating to some of the big issues that lie ahead of us. Im not questioning the value of writing history, of course. But lessons, questions, answers, issuesthese are anodyne words, like food for thought for the present and future. Theyre reminders that it may not be the historians job to detail the lessons or discover the answers. Thats up to us. Theres no seceding from history. The present is both the future of the past and the past of the future. Environmental changes have been and will be shaped, Frankopan writes, by what has already happened in the past, rather than simply by decisions made today. In the second century B.C., the Greek historian Polybius observed that the past once consisted of a series of unrelated episodes. But now, Polybius wrote, history has become an organic whole, a conclusion that seems far truer in the 21st century than it was 2,200 years ago. And yet, climate changewhich binds us all together in a common fatecreates an inescapable feeling that the present has become discontinuous from the past, like an ice shelf breaking free of Antarctica. Frankopans final summary of the present state of global warming is unflinching. It should instill in the reader a deep sense of humility, making it easier to grasp how much we resemble the humans who preceded us, no matter how ancient or unfamiliar they are. If The Earth Transformed has a moral, I think its this: Were as foolish and catastrophically inattentive as any societyor global collection of societiesbefore us. Read: What it would take to see the world completely differently Over and over in the past 10,000 years or so, dynasties, empires, and whole congeries of states have come into existence. Theyve flourished and then vanished. Again and again, humans have organized themselves into complex social entities that have eventually fallen apart, sometimes under climatic pressure, sometimes under forces released by it. Some of those civilizations, such as the Roman empire and the Mughal dynasty, are well known. But do you know the Corded Ware or Bell Beaker or Qijia cultures? How about the Hyksos in Egypt, circa 1640 B.C.? You may have heard of the Abbasid dynasty, which arose in the eighth century, but what about fifth-century Panjakent, a magnificent jewel of a city in what is now Tajikistan? Frankopans erudition is extravagant, as is his range of sources. The number of ancient societies and cultures he adduces as he guides us through time is almost staggering. But so is the fact that none of them survived. Becoming aware of their former existenceso many more of them than you ever imagined, an endless, almost biological skein of societal shapes and forms reaching back thousands of yearsis enough to shift the ground under your feet. We think of this as our world, here and now, a culmination of sorts. But were just another episode in a social version of primary successionlike grasses growing on a new volcanic landscape. O ne of humanitys central myths about ourselves is that we have no habitatnothing as circumscribed or as fixed as the relation between a red-winged blackbird and the wetland it lives beside, or a sea star and its tide pool. We save habitat for other creatures, because the word describes an irrevocable connection between a species and the environmental ground of its existence. (This is how Frankopan usually uses the word.) Humans, we believe, are too adaptable, too inventive to be pinned downtoo flexible to be bounded. Plus, we dont like to think of ourselves as animals. Our adaptability, like our mobility, is part of the evolutionary story we love to tell about Homo sapiens . But climate change is now shoving us up hard against the edges of our global habitat, and we can no longer pretend. Humans are no different from any other species whose habitat has been damaged or impaired or destroyed by usexcept this time, the harm weve done is to ourselves. In The Climate of London , a meteorological study published in 1818, the British chemist Luke Howard wrote this fascinating sentence: Like fishes inhabiting the bottom of an ocean, we are insensible to much of what passes over our heads. Insensible is how it feels to be unaware that you have a habitat. You might say that Howards sentence, written just before a new industrial England began to develop, signals the beginning of the end of what might be called our fishlike existenceour ability to ignore what passes over our heads, before atmospheric carbon began to increase. Reading that phrase, I cant help thinking of John Ruskins observation that one of the last pure sunsets he ever saw was in 1876, nearly 150 years ago. Our habitat is shaped and defined by climate but also by the presence of all other species on Earth (which help shape our climate)something we find almost impossible to acknowledge. Humans have always lived in a planetary ecology that is the sum of all its parts. But in the past century and a half, weve channeled and suppressed and eliminated the reproductive potential of naturethe global torrent of other life in its habitatto an extent thats almost impossible to hold in ones mind. We worry that the effect of climate change on humans will be catastrophic. But for innumerable species on this planet, the catastrophe has already come. We are their catastrophe, with untold effects on our own well-being. The Earth has never been Eden, and there has never been a Garden to return to. But if we dont restrain ourselves now, the restraint the Earth imposes upon us will be brutal. Well come to know the nature of our habitat as we begin to be punished for violating its boundaries. That is the true story of Eden. When you buy a book using a link on this page, we receive a commission. Thank you for supporting The Atlantic.