InDialogue with Marcia Bjornerud and Mark Serreze: Why long-term thinking on the natural world matters

The dangers of a colonial attitude toward the Earth

Marcia Bjornerud

Anthropologist Clifford Geertz famously defined culture as the constellation of stories that groups of humans tell themselves about their place and purpose in the world.  In western culture, with its Judeo-Christian underpinnings grafted to principles of social democracy and capitalism, the stories we share about who we are largely exclude the Natural World.  Nature is at most a passive backdrop – the scenery against which the ‘real’ stories unfold, not a central protagonist in the narrative.

As a result, most of us believe we can simply opt out of Nature’s own long-term plans for the future.  We tend to confuse technological prowess with wisdom.  The people we call “visionaries” base their conceptions of the future on the notion that we should do everything in our power to circumvent the bothersome constraints of the natural world.  We love the stories these great and powerful wizards tell us of how they will make life ‘frictionless’ and reality virtual.  Bedazzled by their shiny gadgets and habituated to the constant streams of novelty they feed us, we in the audience can¹t be bothered to look up and think for ourselves about where exactly we might be going.

And so we behave like bad tourists, entitled conquerors, on Earth, enjoying its amenities and ransacking its bounty without ever having noticed that it has its own ancient language and customs.

This colonial attitude toward the Earth leads to insanities like our continued collective inaction on climate change, or the idea that it could be solved by a silver bullet solution like injecting sulfate aerosols in the stratosphere — and that this will have no unintended consequences.  Or in the extreme case, the delusion that we could create a livable space for ourselves on another planet (once we wreck this one).  Engineering the climate or terraforming Mars sound easy if you are completely unaware of the intrinsic timescales of geological and biological phenomena, the deep evolutionary pathways that gave rise to the world we live in, the intricately choreographed, behind-the-scenes biogeochemical cycles – the housekeeping crew — that make Earth habitable.

We are naïve and impetuous. Earth is old and patient. It has seen good times and bad, hosted biospheres through mass extinctions and evolutionary radiations, reshuffled its continents in countless configurations, constructed and dismantled mountains many times over.  Whether we like it or not, our long-term plans must conform to its long-established practices.  We can alter and accelerate some of these, temporarily, but nature will take notice and take action.  That is, the scenery is going to start directing the play.

We imperil ourselves both physically and psychologically if we don’t bring our conceptions of time in line with nature’s rhythms.  Environmental malefactions and existential malaise are both rooted in a distorted view of humanity’s place in the history of the natural world. 

The solution is to tell different stories about who we are as Earthlings.  That’s all it will take – nothing more than a simple cultural revolution.

Marcia Bjornerud is professor of geology and environmental studies at Lawrence University. She is the author of Timefulness: How Thinking Like a Geologist Can Help Change the World,  Reading the Rocks: The Autobiography of the Earth, and a contributing writer for Elements, the New Yorker’s science and technology blog. She lives in Appleton, Wisconsin.

Beating climate change: Taking action and accepting hard realities

Mark Serreze

Mitigating climate change promises to be a defining battle of the 21st century.  Climate change has already taken hold across the planet. In the Arctic, it is already leading to a radically new environment, with the impacts of rapid warming and shrinking sea ice cascading through the food chain. As a climate scientist who has spent 35 years studying the north, I’ve had a front row seat to watch it all unfold.  Can we beat climate change and maintain a livable planet?   We can, but we must take a long-term view, and accept some hard realities.    

SerrezeCarbon dioxide has a long residence time in the atmosphere, so even if emissions were quickly reduced, much of what we’ve added still will be up there for the foreseeable future.  We are making strong inroads in transitioning to renewable energy sources, notably solar and wind, and have become more efficient in how we use energy.  But for many years to come, we will still be largely dependent on fossil fuels, and greenhouse gas levels will continue to rise.   

It also takes quite a while for the climate to adjust to a change in greenhouse gas levels, mostly because of the immense thermal inertia of the oceans.  The planet has yet to come into balance with the greenhouse gases we’ve already put in the atmosphere – there is heat “in the pipeline”.  Similarly, it will take time for the planet to cool in response to a reduction in carbon dioxide levels.  Simply put, we can’t simply stop climate change in its tracks.

Where does this leave us?  First, stop the blame game and accept where we are.  We have built a modern global society around the immense amount of energy in a lump of coal and a barrel of crude oil.   What we didn’t realize, or perhaps chose not to realize, is that it was a trap.  We need to move on.   Second, prepare to adapt to a warmer world.  It promises to be a rough road, and climate change will have the biggest impacts on those in less developed parts of the world that are least responsible for causing it (and are justified in pointing fingers).  I believe that the planet will manage, provided that we can get a handle on limiting the amount of warming but we have to act quickly – the window of opportunity is closing.

We need to further develop renewables and increase efficiency but also be pragmatic as we transition.  We must to be willing to make honest assessments of the risks and benefits of all energy sources.  As we mobilize against climate change, we must be prepared to be in it for the long haul, and understand that when it comes to powering our future, nothing comes for free. 

Mark C. Serreze is director of the National Snow and Ice Data Center, professor of geography, and a fellow of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder. He is the coauthor of Brave New Arctic and The Arctic Climate System. He lives in Boulder, Colorado.

      

InDialogue with Eelco Rohling and Sean Fleming: Earth’s changing bodies of water

Earth’s bodies of water have gone through considerable changes over time—can these changes tell us anything about climate change—and the future?

Earth’s History and the Oceans

Eelco J. Rohling

Earth’s bodies of water have gone through considerable changes over time—over a lot of time. We have clear geological signs that rivers and lakes have been around for at least 4,400 million years. It never ceases to amaze me that, within 140 million years of its red-hot formation, Earth’s surface had cooled down sufficiently for it to hold fluid water. Then, starting from about 4,000 million years ago, oceans of some shape and form have been around.

Within those ancient bodies of water, life evolved. The earliest signs of life date back to 3,700 million years ago. Then followed a long wait until the first complex life-forms appeared, at around 650 to 700 million years ago. Carbonate coral and shell-reefs became important in shallow waters from about 550 million years ago; many reef systems were formed ever since. And then another major transition took place as late as 125 to 150 million years ago, when carbonate-shelled micro-organisms evolved that rapidly occupied open-ocean surface waters across the world. These organisms are responsible for the formation of geological deposits like the striking white (chalk) cliffs of Dover. Their appearance heralded the start of a fully modern style of operation of the carbon cycle, which includes also atmospheric greenhouse gas concentrations.

Throughout the long history of Earth and its oceans, the carbon cycle and climate changes have been intimately linked. Water is a fantastic substance for absorbing vast quantities of carbon dioxide, and the presence of major bodies of water therefore puts a strong check on greenhouse gas (especially carbon dioxide) concentrations in the atmosphere. Life in the oceans in turn affects the carbon cycle because it involves interaction between dissolved carbon dioxide and both organic matter and carbonate skeletal parts that get (partially) buried and preserved as sediments.

Many ocean sediments eventually get transported into Earth’s hot mantle in subduction zones (think of the Pacific ‘ring of fire,’ where oceanic crust is thrust underneath continental crust). Heating and chemical reactions cause vapour and gas releases, which vent out via volcanoes.  This drives up carbon dioxide levels in the atmosphere and in the oceans. The oceanic part goes directly back into the oceanic carbon cycle. The atmospheric part gets involved in rock weathering on land. This consumes carbon dioxide and releases breakdown products (ions) that flow via rivers back to the oceans, where they help new carbonate formation.

It seems a perfect circle, but it isn’t. There are periods of tiny net carbon dioxide losses or gains. You would not be able to measure these from year to year, but over the multi-million-year timescales of Earth history, they add up to large atmospheric carbon dioxide variations. When this goes up, it gets warmer and weathering increases, which then slowly draws down more carbon dioxide (and vice versa). This way, Earth, with the oceans in a central role, regulates the atmospheric carbon dioxide levels under natural circumstances. It still allows for long, warm periods like the time of the dinosaurs, and excessively cold periods like ice ages or—worse—the exceptional Snowball Earth periods of about 700 million years ago. But overall, the intricately inter-linked long-term carbon cycle processes have held Earth within a ‘habitable’ climate range. Everything changed all the time (and sometimes a lot), but the pace of change was always very slow.

Enter humanity, and our fossil-fuel addiction. We have increased atmospheric carbon dioxide levels in an important manner since the start of the industrial revolution, and especially in the last 60 years. We’re not pushing the actual levels beyond the envelope of where they have been in the natural past—not by a long shot, because we’ve gone from 275 to 410 parts per million, while natural variations have been much greater than that. That’s not the worry. The worry is how fast we’re doing it. We’re doing it easily some 30 to 100 times faster than natural processes have ever done it before (even supervolcanoes cannot get close). Even if all natural removal mechanisms were fired up to 100% their known capacity, then they could offset only about one tenth of our annual emissions.

It is clear, then, that we must drastically reduce our emissions. In addition, it is clear that we must rapidly develop and implement major human-assisted processes of carbon drawdown; that is, we must help nature with the clean-up job. This is important first to deal with ongoing residual emissions that are unavoidable (for example, from cement industry or petrochemical manufacturing), and second to draw down a large part of our past emissions. Both new and existing carbon drawdown approaches are desperately needed at large scales to be able to do this. The sheer amount of carbon removal to be done is enormous.

What can we learn from Ocean and Earth history? That we’re ourselves responsible for the current climate change, and that it’s up to us to deal with it. Mother Nature by itself can and will clean up our greenhouse gases, but don’t wait up for it—it will take her several hundred thousands of years even when working flat-out. We urgently need to lend her a helping hand if we want improvement on societally relevant timescales. Doing so will, incidentally, be a major driver for innovation, development, job creation, and growth potential. What an opportunity!

Eelco J. Rohling is author of The Oceans. He is professor of ocean and climate change in the Research School of Earth Sciences at the Australian National University and at the University of Southampton’s National Oceanography Centre Southampton.

 

Global Warming and our Rivers

Sean W. Fleming

A common misconception about climate change and its impacts on environmental and social systems, like our rivers and water resources, is that it’s something that will only happen at some point in the future.  In reality, climate change is happening now.  Not only does climate vary both naturally due to processes like El Niño, and in response to local-scale human activities like urban heat islands, but global anthropogenic greenhouse gas warming has also been going on for generations – and these signals can be directly detected in actual observational datasets! 

FlemingIn fact, doing so is a crucially important part of understanding the reality and broader impacts of climate change.  When people talk about climate change, they often talk about climate models: math and software that simulate the global climate system.  And because climate models are exactly that – detailed representations of climate, but not of everything climate affects – to understand the impacts on water resources, the predictions of those climate models are taken by hydrologists and other scientists and engineers and run through still other models, such as simulations of watershed hydrology, water quality, habitat quantity and quality, or reservoir operations.  All these models are amazing technical feats, and they’re fantastic for isolating the impacts of human-caused global climate change from other sources of environmental variability.  But by necessity, they contain a lot of simplifications.  Rivers are immensely complex systems that integrate the effects of just about everything in their watersheds, from weather and climate, to forests and icefields, to land use changes like forestry and urban sprawl.  It turns out they’re also full of unexpected surprises. 

So, while the physics-based virtual realities of process simulation models are great tests of what we know about the world and are our best bet for making predictions based on that knowledge, they can only contain what we know, not what we don’t know.  In contrast, drawing sophisticated data analytics algorithms from statistics, digital signal processing, information theory, and artificial intelligence, and applying them to actual measurements of climate and the things it affects, provides a valuable “ground truth” – giving direct empirical evidence for the impacts of climate change on rivers, and often revealing previously unknown patterns that the next generation of models must then seek to explain and, ultimately, predict.

My favorite example is how mountain glaciers control water resource responses to climate change.  My doctoral studies began in 2001 with a glacier science expedition to the high peaks of the Yukon-Alaska-British Columbia border region.  Hearing summer melt water run deep in the crevasses of Trapridge Glacier and watching white-water streams gushing from its terminus, I decided to focus my research on statistical and machine learning studies of decades-long historical streamflow data in glacial watersheds.  The goal was to understand how these gigantic ice cubes modify the downstream expressions of climate change – specifically, by comparing climate variability and change responses in several glacier-fed rivers to a control population of nearby rivers that didn’t have glaciers in their headwaters. 

We made a few discoveries.  One revelation was that recent global warming affected the net downstream flow of glacial rivers in a completely different way from non-glacial watersheds: glacial rivers grew larger while non-glacial rivers shrank.   It was solid evidence of the present reality of climate change, but at the same time, specific patterns like this were poorly represented, if at all, in environmental models.  With further refinement by many scientists worldwide, this knowledge has since become part of a standard model of how water resources downstream of mountain glaciers – which lie at the heart of the continental “water towers” of the Rockies, Andes, Alps, and Himalayas, in turn feeding the headwaters of the Columbia, Amazon, Danube, Brahmaputra, and Yangtze rivers, among others – are affected by climate change.

Sean W. Fleming is author of Where the River Flows. He has two decades of experience in the private, public, and nonprofit sectors in the United States, Canada, England, and Mexico, ranging from oil exploration to operational river forecasting to glacier science. He holds faculty positions in the geophysical sciences at the University of British Columbia and Oregon State University.

Opportunity costs: can carbon taxing become a positive-sum game?

Climate change, caused by human activity, is arguably the biggest single problem facing the world today, and it is deeply entangled with the question of how to lift billions of people out of poverty without destroying the global environment in the process. But climate change also represents a crisis for economists (I am one). Decades ago, economists developed solutions – or variants on the same solution – to the problem of pollution, the key being the imposition of a price on the generation of pollutants such as carbon dioxide (CO2). The idea was to make visible, and accountable, the true environmental costs of any production process. 

Carbon pricing could stabilise the global climate, and cap unwanted warming, at a fraction of the cost that we are likely to end up paying in other ways. And as emissions were rapidly reduced, we could save enough to compensate most of the ‘losers’, such as displaced coal miners; a positive-sum solution. Yet, carbon pricing has been mostly spurned in favour of regulatory solutions that are significantly more costly. Why?

Environmental pollution is one of the most pervasive and intractable failures of market systems (and Soviet-style central planning). Almost every kind of economic activity produces harmful byproducts, which are costly to dispose of safely. The cheapest thing to do is to dump the wastes into waterways or the atmosphere. Under pure free-market conditions, that’s precisely what happens. Polluters pay nothing for dumping waste while society bears the cost.

Since most energy in modern societies comes from burning carbon-based fuels, solving this problem, whether through new technology or altered consumption patterns, will require changes in a vast range of economic activities. If these changes are to be achieved without reducing standards of living, or obstructing the efforts of less developed countries to lift themselves out of poverty, it is important to find a path to emissions reduction that minimises costs.

But since pollution costs aren’t properly represented in market prices, there’s little use in looking at the accounting costs that appear in corporate balance sheets, or the market-based costs that go into national accounting measures such as Gross Domestic Product (GDP). For economists, the right way to think is in terms of ‘opportunity cost’, which can be defined as follows: The opportunity cost of anything of value is what you must give up so that you can have it. So how should we think about the opportunity cost of CO2 emissions?

We could start with the costs imposed on the world’s population as a whole from climate change, and measure how this changes with additional emissions. But this is an impossibly difficult task. All we know about the costs of climate change is that they will be large, and possibly catastrophic. It’s better to think about carbon budgets. We have a good idea how much more CO2 the world can afford to emit while keeping the probability of dangerous climate change reasonably low. A typical estimate is 2,900 billion tonnes – of which 1,900 billion tonnes have already been emitted.

Within any given carbon budget, an additional tonne of CO2 emitted from one source requires a reduction of one tonne somewhere else. So, it is the cost of this offsetting reduction that determines the opportunity cost of the additional emission. The problem is that, as long as the CO2 generated ‘disappears’ into the atmosphere (and, eventually, the oceans), corporations and households do not bear the opportunity cost of the CO2 they emit.

In a properly working market economy, prices reflect opportunity costs (and vice versa). A price for CO2 emissions high enough to keep total emissions within the carbon budget would ensure that the opportunity cost of increasing emissions would be equal to the price. But how can this be brought about?

In the 1920s, the English economist Arthur Pigou suggested imposing taxes on firms generating pollution. This would make the (tax-inclusive) prices paid by those firms reflect social cost. An alternative approach, developed by the Nobel laureate Ronald Coase, stresses the role of property rights. Rather than setting a price for pollution, society decides how much pollution can be tolerated, and creates property rights (emissions permits) reflecting that decision. Companies that want to burn carbon must acquire emissions permits for the CO2 they produce. Whereas the carbon-tax approach determines a price and lets markets determine the volume of polluting activity, the property-rights approach sets the volume and lets the market determine the price.

There is no necessary link between imposing a carbon tax and distributing the resulting payments. However, natural intuitions of justice suggest that the revenue from carbon pricing should go to those adversely effected. At a national level, the proceeds could be used to offset the costs borne by low-income households. More ambitiously, a truly just system of global property rights would give everyone equal rights, and require those who want to burn more than their share of carbon (mostly, the global rich) to buy rights from those who burn less.

This raises the question of whether emissions rights should be equalised going forward, or whether historical emissions should be taken into account, allowing poorer nations to ‘catch up’. This debate has been rendered largely irrelevant by dramatic drops in the price of renewable energy that have sidelined development strategies based on fossil fuels. The best solution seems to be ‘contract and converge’. That is, all nations should converge as fast as possible to an emissions level far below that of currently developed countries, then phase out emissions entirely.

Carbon taxes have already been introduced in various places, and proposed in many more, but have met with vigorous resistance nearly everywhere. Emissions-permit schemes have been somewhat more successful, notably in the European Union, but have not taken off in the way envisaged when the Kyoto Protocol was signed in 1997. This disappointing outcome requires explanation.

The ideas of Pigou and Coase provide a theoretically neat answer to the market-failure problem. Unfortunately, they run into the more fundamental problem of income distribution and property rights. If governments create emissions rights and auction them, they create public property out of a resource (the atmosphere) that was previously available for use (and misuse) free of charge. The same is true when a carbon tax is proposed.

Whether property rights are created explicitly, as in the Coase approach, or implicitly, through the carbon taxes advocated by Pigou, there will be losers as well as gainers from the resulting change in the distribution of property rights and, therefore, market income. Not surprisingly, those potential losers have resisted market-based policies of pollution control.

The strongest resistance arises when businesses that have previously dumped their waste into airways and waterways free of charge are forced to bear the opportunity costs of their actions by paying taxes or purchasing emissions rights. Such businesses can call on an array of lobbyists, think tanks and friendly politicians to defend their interests.

Faced with these difficulties, governments have often fallen back on simpler options such as regulations and ad hoc interventions, such as feed-in tariffs and renewable-energy targets. These solutions are more costly and frequently more regressive, not least as the size of the cost burden and the way it is distributed is obscure and hard to understand. Yet the likely costs of climate change are so great that even second-best solutions such as direct regulation are preferable to doing nothing; and the delays caused by resistance from business, and from the ideologically driven science deniers in their pay, have been such that, in the short run, emergency interventions will be required.

Still, the need to respond to climate change is not going away any time soon, and the costs of regulatory solutions will continue to mount. If we are to stabilise the global climate without hampering efforts to end the scourge of global poverty, some form of carbon pricing is essential.

Economics in Two Lessons: Why Markets Work So Well, and Why They Can Fail So Badly by John Quiggin is forthcoming via Princeton University Press.Aeon counter – do not remove

John Quiggin is the President’s Senior Fellow in Economics at the University of Queensland in Brisbane, Australia. His previous book, Zombie Economics: How Dead Ideas Still Walk among Us (Princeton), has been translated into eight languages. He has written for the New York Times and the Economist, among other publications, and is a frequent blogger for Crooked Timber and on his own website: www.johnquiggin.com. Twitter @JohnQuiggin

This article was originally published at Aeon and has been republished under Creative Commons.

Martin Rees on On The Future

Humanity has reached a critical moment. Our world is unsettled and rapidly changing, and we face existential risks over the next century. Various prospects for the future—good and bad—are possible. Yet our approach to the future is characterized by short-term thinking, polarizing debates, alarmist rhetoric, and pessimism. In this short, exhilarating book, renowned scientist and bestselling author Martin Rees argues that humanity’s future depends on our taking a very different approach to thinking about and planning for tomorrow. Rich with fascinating insights into cutting-edge science and technology, this book will captivate anyone who wants to understand the critical issues that will define the future of humanity on Earth and beyond.

Are you an optimist?

I am writing this book as a citizen, and as an anxious member of the human species. One of its unifying themes is that humanity’s flourishing depends on how wisely science and technology are deployed. Our lives, our health, and our environment can benefit still more from further advances in biotech, cybertech, robotics, and AI. There seems no scientific impediment to achieving a sustainable and secure world, where all enjoy a lifestyle better than those in the ‘west’ do today (albeit using less energy and eating less meat). To that extent, I am a techno-optimist. But what actually happens depends on politics and ethical choices.

Our ever more interconnected world is exposed to new vulnerabilities. Even within the next decade or two, robotics will disrupt working patterns, national economies, and international relations. A growing and more demanding population puts the natural environment under strain; peoples’ actions could trigger dangerous climate change and mass extinctions if ‘tipping points’ are crossed—outcomes that would bequeath a depleted and impoverished world to future generations. But to reduce these risks, we need to enhance our understanding of nature and deploy appropriate technology (zero-carbon energy, for instance) more urgently. Risks and ethical dilemmas can be minimized by a culture of ‘responsible innovation’, especially in fields like biotech, advanced AI and geoengineering; and we’ll need to confront new ethical issues—‘designer babies’, blurring of the line between life and death, and so forth—guided by priorities and values that science itself can’t provide.

Is there a moral imperative as well?

There has plainly been a welcome improvement in most people’s lives and life-chances—in education, health, and lifespan. This is owed to technology. However, it’s surely a depressing indictment of current morality that the gulf between the way the world is and the way it could be is wider than it ever was. The lives of medieval people may have been miserable compared to ours, but there was little that could have been done to improve them. In contrast, the plight of the ‘bottom billion’ in today’s world could be transformed by redistributing the wealth of the thousand richest people on the planet. Failure to respond to this humanitarian imperative, which nations have the power to remedy—surely casts doubt on any claims of institutional moral progress. That’s why I can’t go along with the ‘new optimists’ who promote a rosy view of the future, enthusing about improvements in our moral sensitivities as well as in our material progress. I don’t share their hope in markets and enlightenment.

A benign society should, at the very least, require trust between individuals and their institutions. I worry that we are moving further from this ideal for two reasons: firstly, those we routinely have to deal with are increasingly remote and depersonalised; and secondly, modern life is more vulnerable to disruption—‘hackers’ or dissidents can trigger incidents that cascade globally. Such trends necessitate burgeoning security measures. These are already irritants in our everyday life—security guards, elaborate passwords, airport searches and so forth—but they are likely to become ever more vexatious. Innovations like blockchain could offer protocols that render the entire internet more secure. But their current applications—allowing an economy based on cryptocurrencies to function independently of traditional financial institutions—seem damaging rather than benign. It’s depressing to realize how much of the economy is dedicated to activities that would be superfluous if we felt we could trust each other. (It would be a worthwhile exercise if some economist could quantify this.)

But what about politics? 

In an era where we are all becoming interconnected, where the disadvantaged are aware of their predicament, and where migration is easy, it’s hard to be optimistic about a peaceful world if a chasm persists, as deep as it is today’s geopolitics, between the welfare levels and life-chances in different regions. It’s specially disquieting if advances in genetics and medicine that can enhance human lives are available to a privileged few, and portend more fundamental forms of inequality. Harmonious geopolitics would require a global distribution of wealth that’s perceived as fair—with far less inequality between rich and poor nations. And even without being utopian it’s surely a moral imperative (as well as in the self-interest of fortunate nations) to push towards this goal. Sadly, we downplay what’s happening even now in far-away countries. And we discount too heavily the problems we’ll leave for new generations. Governments need to prioritise projects that are long-term in a political perspectives, even if a mere instant in the history of our planet.

Will super intelligent AI out-think humans?

We are of course already being aided by computational power. In the ‘virtual world’ inside a computer astronomers can mimic galaxy formation; meteorologists can simulate the atmosphere. As computer power grows, these ‘virtual’ experiments become more realistic and useful. And AI will make discoveries that have eluded unaided human brains. For example, there is a continuing quest to find the ‘recipe’ for a superconductor that works at ordinary room temperatures. This quest involves a lot of ‘trial and error’, because nobody fully understands what makes the electrical resistance disappear more readily in some materials than in others. But it’s becoming possible to calculate the properties of materials, so fast that millions of alternatives can be computed, far more quickly than actual experiments could be done. Suppose that a machine came up with a novel and successful recipe. It would have achieved something that would get a scientist a Nobel prize. It would have behaved as though it had insight and imagination within its rather specialized universe—just as Deep Mind’s Alpha Go flummoxed and impressed human champions with some of its moves. Likewise, searches for the optimal chemical composition for new drugs will increasingly be done by computers rather than by real experiments.

Equally important is the capability to ‘crunch’ huge data-sets. As an example from genetics, qualities like intelligence and height are determined by combinations of genes. To identify these combinations would require a machine fast enough to scan huge samples of genomes to identify small correlations. Similar procedures are used by financial traders in seeking out market trends, and responding rapidly to them, so that their investors can top-slice funds from the rest of us.

Should humans spread beyond Earth?

The practical case for sending people into space gets weaker as robots improve. So the only manned ventures (except for those motivated by national prestige) will be high-risk, cut price, and privately sponsored—undertaken by thrill-seekers prepared even to accept one-way tickets. They’re the people who will venture to Mars. But there won’t be mass emigration: Mars is far less comfortable than the South Pole or the ocean bed. It’s a dangerous delusion to think that space offers an escape from Earth’s problems. We’ve got to solve these here. Coping with climate change may seem daunting, but it’s a doddle compared to terraforming Mars. There’s no ‘Planet B’ for ordinary risk-averse people.

But I think (and hope) that there will be bases on Mars by 2100. Moreover we (and our progeny here on Earth) should cheer on the brave adventurers who go there. The space environment is inherently hostile for humans, so, precisely because they will be ill-adapted to their new habitat, the pioneer explorers will have a more compelling incentive than those of us on Earth to redesign themselves. They’ll harness the super-powerful genetic and cyborg technologies that will be developed in coming decades. These techniques will, one hopes, be heavily regulated on Earth; but ‘settlers’ on Mars will be far beyond the clutches of the regulators. This might be the first step towards divergence into a new species. So it’s these spacefaring adventurers, not those of us comfortably adapted to life on Earth, who will spearhead the post-human era. If they become cyborgs, they won’t need an atmosphere, and may prefer zero-g—perhaps even spreading among the stars.

Is there ‘intelligence’ out there already?

Perhaps we’ll one day find evidence of alien intelligence. On the other hand, our Earth may be unique and the searches may fail. This would disappoint the searchers. But it would have an upside for humanity’s long-term resonance. Our solar system is barely middle aged and if humans avoid self-destruction within the next century, the post-human era beckons. Intelligence from Earth could spread through the entire Galaxy, evolving into a teeming complexity far beyond what we can even conceive. If so, our tiny planet—this pale blue dot floating in space—could be the most important place in the entire cosmos.

What about God?

I don’t believe in any religious dogmas, but I share a sense of mystery and wonder with many who do. And I deplore the so called ‘new atheists’—small-time Bertrand Russell’s recycling his arguments—who attack religion. Hard-line atheists must surely be aware of ‘religious’ people who are manifestly neither unintelligent nor naïve, though they make minimal attempts to understand them by attacking mainstream religion, rather than striving for peaceful coexistence with it; they weaken the alliance against fundamentalism and fanaticism. They also weaken science. If a young Muslim or evangelical Christian is told at school that they can’t have their God and accept evolution, they will opt for their God and be lost to science. When so much divides us, and change is disturbingly fast, religion offers bonding within a community. And its heritage, linking its adherents with past generations, should strengthen our motivation not to leave a degraded world for generations yet to come.

Do scientists have special obligations?

It’s a main theme of my book that our entire future depends on making wise choices about how to apply science. These choices shouldn’t be made just by scientists: they matter to us all and should be the outcome of wide public debate. But for that to happen, we all need enough ‘feel’ for the key ideas of science, and enough numeracy to assess hazards, probabilities and risks—so as not to be bamboozled by experts, or credulous of populist sloganising. Moreover, quite apart from their practical use, these ideas should be part of our common culture. More than that, science is the one culture that’s truly global. It should transcend all barriers of nationality. And it should straddle all faiths too.

I think all scientists should divert some of their efforts towards public policy—and engage with government, business, and campaigning bodies. And of course the challenges are global. Coping with potential shortage of resources—and transitioning to low carbon energy—can’t be solved by each nation separately.

The trouble is that even the best politicians focus mainly on the urgent and parochial—and getting reelected. This is an endemic frustration for those who’ve been official scientific advisors in governments. To attract politicians’ attention you must get headlined in the press, and fill their inboxes. So scientists can have more leverage indirectly—by campaigning, so that the public and the media amplify their voice. Rachel Carson and Carl Sagan, for instance, were preeminent exemplars of the concerned scientist—with immense influence through their writings, lectures and campaigns, even before the age of social media and tweets

Science is a universal culture, spanning all nations and faiths. So scientists confront fewer impediments on straddling political divides.

Does being an astronomer influence your attitude toward the future?

Yes, I think it makes me specially mindful of the longterm future. Let me explain this. The stupendous timespans of the evolutionary past are now part of common culture (maybe not in Kentucky, or in parts of the Muslim world). But most people still somehow think we humans are necessarily the culmination of the evolutionary tree. That hardly seems credible to an astronomer—indeed, we could still be nearer the beginning than the end. Our Sun formed 4.5 billion years ago, but it’s got 6 billion more before the fuel runs out. It then flares up, engulfing the inner planets. And the expanding universe will continue—perhaps forever. Any creatures witnessing the Sun’s demise won’t be human—they could be as different from us as we are from slime mold. Posthuman evolution—here on Earth and far beyond—could be as prolonged as the evolution that’s led to us, and even more wonderful. And of course this evolution will be faster than Darwinian: it happens on a technological timescale, driven by advances in genetics and AI.

But (a final thought) even in the context of a timeline that extends billions of years into the future, as well as into the past. this century is special. It’s the first where one species—ours—has our planet’s future in its hands. Our creative intelligence could inaugurate billions of years of posthuman evolution even more marvelous than what’s led to us. On the other hand, humans could trigger bio, cyber, or environmental catastrophes that foreclose all such potentialities. Our Earth, this ‘pale blue dot’ in the cosmos, is a special place. It may be a unique place. And we’re its stewards at a specially crucial era—the anthropocene. That’s a key message for us all, whether or not we’re astronomers, and a motivation for my book.

Martin Rees is Astronomer Royal, and has been Master of Trinity College and Director of the Institute of Astronomy at Cambridge University. As a member of the UK’s House of Lords and former President of the Royal Society, he is much involved in international science and issues of technological risk. His books include Our Cosmic HabitatJust Six Numbers, and Our Final Hour (published in the UK as Our Final Century). He lives in Cambridge, UK.

David Vogel on California Greenin’

VogelOver the course of its 150-year history, California has successfully protected its scenic wilderness areas, restricted coastal oil drilling, regulated automobile emissions, preserved coastal access, improved energy efficiency, and, most recently, addressed global climate change. How has this state, more than any other, enacted so many innovative and stringent environmental regulations over such a long period of time? The first comprehensive look at California’s history of environmental leadership, California Greenin’ shows why the Golden State has been at the forefront in setting new environmental standards, often leading the rest of the nation. As environmental policy debates continue to grow more heated, California Greenin’ demonstrates that the Golden State’s impressive record of environmental accomplishments holds lessons not just for the country but for the world.

Why did you decide to focus your book on California?

Much has been written on every aspect of California’s environmental history. Books have been written on the state’s forests and wilderness areas, cars and air pollution in Los Angeles, oil drilling in southern California, the protection of the coast and the San Francisco Bay Area and, most recently, the state’s regulations to improve energy efficiency and stem the risks of global climate change. But no one had ever sought to answer what struck me as a central question, namely why has California long been the nation’s “greenest” state? I wrote this book to answer that question.

What are some important examples of California’s environmental leadership?

California enacted the world’s first emissions controls on automobiles and established the nation’s first coastal protection authority. Yosemite was the first protected wilderness in the United States and by 1890 three of nation’s four national parks were located in the state. California issued the nation’s first energy efficiency standards for appliances and buildings. Its greenhouse gas reduction targets are the most ambitious in the United States. Half of the nation’s rooftop solar installations are in California.

How do you account for the state’s long record of environmental innovation?

It traces back to California’s geography. The “Golden State” has an unusually beautiful natural environment. Its coastal area encompasses the best weather in the United States. It has a long and scenic coastline, miles of sand beaches, and inland there are the granite formations, rivers, lakes and valleys of the Sierra Nevada Mountains. The state’s forests contain the spectacular redwoods and sequoias, the largest and oldest living species on the planet. But every aspect of this attractive environment has been continually threatened by rapid economic development and population growth. It is in response to these threats that Californians have mobilized to protect the environmental amenities that they valued.

What is the “California effect?”

The “California effect” refers to the impact California has had in strengthening environmental protection outside its borders. The most important example is automotive emissions standards These were first introduced in California and then subsequently adopted by the federal government. Virtually all of the important innovations in emissions controls, such unleaded gasoline and the two-way catalytic convertor, originated in California and were then nationally mandated. California’s innovative greenhouse gas emission standards for vehicles were subsequently adopted by the Obama Administration. Significantly, California is the only state permitted by the federal government to issue its own automotive regulations. Other states then have the option of adapting California’s more stringent standards and several states have chosen to do so.

What most surprised you in writing this book?

I was most struck by the role business has played in supporting environmental protection. Business has been traditionally viewed as the main opponent of stronger environmental standards. But in the case of California influential business interests have often actively backed stronger regulations  For example, during the late 19th and early 20th centuries the Southern Pacific Railroad lobbied to protect the sequoias in the Sierra Nevada mountains, while during the mid 20th century, the Los Angeles real estate community led the political struggle to reduce air pollution. Southern California’s shoreline property developers were the main opponents of coastal oil drilling. California’s renewable energy industry and clean tech investors have benefited from and been strong supporters of the state’s climate change initiatives. In sum, many business interests have recognized the economic benefits of placing the state on a greener growth trajectory.   

What practical lessons can other states learn from California?

The United States is a federal system in which states can play important policy roles. They have enormous potential to improve environmental quality. What other states can also learn from California is that regulations are more likely to be supported if they directly improve the quality of life of local communities, provide economic as well as environmental benefits, receive some business 6backing, and are administrated by competent public authorities. California’s example of regulatory leadership can and hopefully should be followed by other states.

What do you hope readers will take away from the book? 

That protecting the environment and growing economically can go hand in hand. Since the 1860s California has consistently enacted the nation’s most stringent, comprehensive and innovative environmental standards and its economy is now the sixth largest in the worlds. Had it not made such vigorous efforts to protect its fragile natural environment, California would now be a much less desirable place to visit, to live to work, and to invest. California’s economy has benefited substantially from its environmental regulations. This can be true for all states as well.

David Vogel is professor emeritus in the Haas School of Business and the Department of Political Science at the University of California, Berkeley. His many books include The Politics of Precaution and The Market for Virtue.

Mark Serreze: Becoming A Scientist

In honor of Earth Day, Princeton University Press will be highlighting the contributions that scientists make to our understanding of the world around us through a series of blog posts written by some of our notable Earth Science authors. Keep a look out for this series all month long.

Mark Serreze, investigating the pressure ridges in the Arctic.

What is it that leads someone to become a scientist? It varies, but from what I’ve seen, it’s often a combination of nature and nurture. Just as some people seem to have an inherent knack for writing making music, or cooking, I think that some of us are wired to become scientists. In turn, there is often someone we can look back to—parents or perhaps a teacher—that encouraged or inspired us to pursue a science career.

I had an interest in science from when I was very young, and I was always full of questions about the natural world. The first book I ever owned is “The Golden Book of Science” 1963 edition—featuring 1-2 page essays on everything from geology to insects to the weather. Each night, at my insistence, my mother would read one of them to me. To this day, I still own the book.

When I wasn’t reading, I could spend hours outside marveling at the organized industriousness of ants as they built their anthills, or looking at colorful rocks with a magnifying glass. I was enthralled with the burgeoning manned space flight program, and, sitting beside my mother and staring at the black TV while she ironed clothes, watched in awe at the Project Gemini rocket launches.   

As for the nurture part, I had an advantage in that both of my parents were chemists with Master’s degrees. This was at a time it was quite unusual for women to hold advanced degrees. They met in the laboratory. Mom was a whiz when it came to thermodynamics, and Dad apparently knew everything there was to know about acrylic plastics. Ours was indeed an odd household. While my siblings and I chafed under a rather strict Catholic upbringing, at the same time we were very much free-range kids, and scientific experimentation of all sorts was quite acceptable.  

At one point, after getting a chemistry set for Christmas, I thought I might become a chemist myself. These were not the boring, defanged chemistry sets of today – back then, they included chemicals that, when properly mixed, yielded career-inspiring reactions. I later got heavily into model rocketry, astronomy, and civil engineering, building small dams across the stream running past our house to improve the habitat for the frogs. Included among the more foolish (albeit highly educational) endeavors was a scientifically-based experiment on the feasibility of riding ice floes down the Kennebunk River. Then there was the time when an experiment in pyrotechnics gone wrong ended up with a frantic call to the fire department to douse a five-acre conflagration in the neighbor’s field.

Years before I ever got into college I knew I was going to be a research scientists of some type, for, through nature and nurture, the roots were already there. As I talk about in my book, Brave New Arctic, a number decisions and events came together – mixed with some blind, dumb luck – to eventually steer me towards a career in climate science. What I could never have foreseen is how, through these events and decisions, and then through 35 years of research, I’d find myself in the position to tell the story about the dramatic transformation of the North.

Climate scientists, like myself, have to deal with an added challenge that climate change is a highly polarized subject. There are the frequent questions from the media: Will there be a new record low in Arctic sea ice extent this year? Why does it matter? Why is the Arctic behaving so differently than the Antarctic? It can be overwhelming at times. Then there are the emails, phone calls and tweets from those who simply want to rant. While I get a lot of emails from people fully on board with the reality that humans are changing the climate and want to get straight answers about something they’ve heard or read about, I also have a growing folder in my inbox labeled “Hate Mail”. Some very unflattering things have been said about me on social media and across the web. I’ve had to grow a thick skin.  

Making a career as a research scientist is not for everyone. Science is not the sort of thing that is easy to put aside at the end of the day. It gnaws at you. The hours are long, and seldom lead to monetary riches. It can also be a frustrating occupation, such as when realizing that, after months of research pursuing a lead, you’ve hit a dead end.

We chose to be scientists because it’s what we love to do. We live for those “aha” moments when the hard work pays off, and we discover something new that advances our understanding.

In writing this book I was forced to dig deeply to understand my own evolution as a scientist, and to document insights from other scientists who, like me, were there at the beginning when the Arctic still looked like the Arctic of old. It’s been an adventure, and when I someday retire (which is a very hard thing for scientists to do,) I hope to be able to look back and say that that this book opened some eyes, and inspired others to follow their own path to becoming a scientist.

 

Mark Serreze is director of the National Snow and Ice Data Center, professor of geography, and a fellow of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder. He is the coauthor of The Arctic Climate System. He lives in Boulder, Colorado.

Mark C. Serreze: Approaching the March Sea Ice Maximum

Author Mark C. Serreze standing next to a snow machine in the Arctic.

The floating sea ice atop the Arctic Ocean waxes and wanes with the seasons. The maximum extent typically occurs around the second week of March, at which time ice has historically covered an area a bit less than twice the size of the contiguous United States. The term “Arctic sea ice extent” is actually a bit of a misnomer, for at or near the seasonal maximum, sea ice is found well south of the Arctic Circle, covering all of Hudson Bay and parts of the Bering Sea, the Sea of Okhotsk, the Baltic Sea and the Gulf of St. Lawrence.  With the start of spring, the ice cover begins to melt.  Initially, the growing warmth of spring slowly nibbles away at the southern edges of the ice pack.  The pace of melt picks up in May and June, and then gets underway in earnest in July.  As the sun gets lower in the sky in August, the melt slows.  The seasonal minimum in ice extent usually occurs in mid-September – at that time, the ice covers less than half of what it did in March, and ice is restricted to the Arctic Ocean proper.  As the sun then sets over the Arctic Ocean, the ice cover begins to grow again, renewing the cycle that has been going on for millions of years. 

But things are changing fast.  Earth observation satellites have been recording changes in Arctic sea ice extent since 1979.  These records show that sea ice extent is declining in all months, with the largest change in September, at the end of the melt season.  The downward trend for September is a whopping 13% per decade. The trends are by no means smooth – there are big ups and downs from month to month and year to year, but the pattern is clear. 

Scientists have long been at work to determine what sea ice conditions were like before the satellite era.  Data from shore observations, ship and aircraft reports, and before aviation, sources like logbook entries from whaling ships, extend the record back to 1850.  Paleoclimate reconstructions bring the record back a thousand years before today.  There is no evidence in any of these records for sea ice trends like we’ve seen over the past 40 years.  They are unprecedented.  The conclusion is inescapable – the Arctic Ocean is quickly losing its floating sea ice cover.  The summer ice cover may be gone 30 or 40 years from now.

At the University of Colorado National Snow and Ice Center (NSIDC), where I’ve been the director since 2009, we track the Arctic sea ice cover on a daily basis.  Every August, we start to brace ourselves for the inevitable tidal wave of questions from the media and interested public about what September will bring.  Questions like: Will there be a new record low in sea ice extent this year?  When will the Arctic completely lose its summer sea ice cover?  What will this mean for the rest of the planet?  We also get our share of flak from the skeptics, eager to tell us that this is all some sort of natural climate cycle, or that nothing is happening at all; we’re making it up and fudging the records.  We shrug this off and diligently continue processing the satellite data and report on what is happening. The data does not lie.

Until a few years ago, the March sea ice maximum went relatively unnoticed.  By comparison to September, the changes being seen in winter weren’t especially spectacular, and for good reason – even in a warming Arctic, it still gets cold and dark in winter and sea ice forms and covers a big area.  The ice that grows in autumn and winter is thinner than it used to be, but to the satellite sensors that we use to determine ice extent, thin ice looks pretty much the same as thick ice.

Things changed in 2015, when sea ice extent at the March maximum set a new record low.  Then the winter of 2015-2016 saw a mind-boggling heat wave over the Arctic Ocean.   At the end of December 2015, there was a brief period when the surface temperature at the North Pole rose to the melting point. In all my years of studying the Arctic, I’d never seen anything like it. It stayed warm and on March 24, when Arctic sea ice reached its seasonal maximum extent, it had bested the low mark set in 2015.  The winter of 2016/2017 was in many respects a repeat.   At the winter solstice on Dec. 22, temperatures near the North Pole were up 20 degrees Celsius (35 degrees Fahrenheit) above average.  When March 2017 rolled around, another new record low in extent had been set. The Arctic has gone crazy.

We’re still coming to grips with understanding these records lows in the winter ice cover. While the heat waves are clearly related to weather patterns bringing in warm air from the south, what’s the cause of these patterns?  While more ocean heat seems to be coming into the Arctic Ocean from the Pacific through the Bering Strait, why is this happening?  The inflow of ocean heat from the Atlantic has also changed in puzzling ways that inhibit winter ice formation in places like the Barents Sea.  

In short, while we know a great deal about what is happening to the Arctic and where it is headed, the emerging Brave New Arctic continues to challenge us.  Maybe we shouldn’t be all that surprised – after all, scientists have long known that, as the climate warms, the biggest changes would be seen the Arctic. That doesn’t mean that we can’t be amazed.

 

Mark C. Serreze is is director of the National Snow and Ice Data Center, professor of geography, and a fellow of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder. He lives in Boulder, Colorado.

Kyle Harper: How climate change and disease helped the fall of Rome

HarperAt some time or another, every historian of Rome has been asked to say where we are, today, on Rome’s cycle of decline. Historians might squirm at such attempts to use the past but, even if history does not repeat itself, nor come packaged into moral lessons, it can deepen our sense of what it means to be human and how fragile our societies are.

In the middle of the second century, the Romans controlled a huge, geographically diverse part of the globe, from northern Britain to the edges of the Sahara, from the Atlantic to Mesopotamia. The generally prosperous population peaked at 75 million. Eventually, all free inhabitants of the empire came to enjoy the rights of Roman citizenship. Little wonder that the 18th-century English historian Edward Gibbon judged this age the ‘most happy’ in the history of our species – yet today we are more likely to see the advance of Roman civilisation as unwittingly planting the seeds of its own demise.

Five centuries later, the Roman empire was a small Byzantine rump-state controlled from Constantinople, its near-eastern provinces lost to Islamic invasions, its western lands covered by a patchwork of Germanic kingdoms. Trade receded, cities shrank, and technological advance halted. Despite the cultural vitality and spiritual legacy of these centuries, this period was marked by a declining population, political fragmentation, and lower levels of material complexity. When the historian Ian Morris at Stanford University created a universal social-development index, the fall of Rome emerged as the greatest setback in the history of human civilisation.

Explanations for a phenomenon of this magnitude abound: in 1984, the German classicist Alexander Demandt catalogued more than 200 hypotheses. Most scholars have looked to the internal political dynamics of the imperial system or the shifting geopolitical context of an empire whose neighbours gradually caught up in the sophistication of their military and political technologies. But new evidence has started to unveil the crucial role played by changes in the natural environment. The paradoxes of social development, and the inherent unpredictability of nature, worked in concert to bring about Rome’s demise.

Climate change did not begin with the exhaust fumes of industrialisation, but has been a permanent feature of human existence. Orbital mechanics (small variations in the tilt, spin and eccentricity of the Earth’s orbit) and solar cycles alter the amount and distribution of energy received from the Sun. And volcanic eruptions spew reflective sulphates into the atmosphere, sometimes with long-reaching effects. Modern, anthropogenic climate change is so perilous because it is happening quickly and in conjunction with so many other irreversible changes in the Earth’s biosphere. But climate change per se is nothing new.

The need to understand the natural context of modern climate change has been an unmitigated boon for historians. Earth scientists have scoured the planet for paleoclimate proxies, natural archives of the past environment. The effort to put climate change in the foreground of Roman history is motivated both by troves of new data and a heightened sensitivity to the importance of the physical environment. It turns out that climate had a major role in the rise and fall of Roman civilisation. The empire-builders benefitted from impeccable timing: the characteristic warm, wet and stable weather was conducive to economic productivity in an agrarian society. The benefits of economic growth supported the political and social bargains by which the Roman empire controlled its vast territory. The favourable climate, in ways subtle and profound, was baked into the empire’s innermost structure.

The end of this lucky climate regime did not immediately, or in any simple deterministic sense, spell the doom of Rome. Rather, a less favourable climate undermined its power just when the empire was imperilled by more dangerous enemies – Germans, Persians – from without. Climate instability peaked in the sixth century, during the reign of Justinian. Work by dendro-chronologists and ice-core experts points to an enormous spasm of volcanic activity in the 530s and 540s CE, unlike anything else in the past few thousand years. This violent sequence of eruptions triggered what is now called the ‘Late Antique Little Ice Age’, when much colder temperatures endured for at least 150 years. This phase of climate deterioration had decisive effects in Rome’s unravelling. It was also intimately linked to a catastrophe of even greater moment: the outbreak of the first pandemic of bubonic plague.

Disruptions in the biological environment were even more consequential to Rome’s destiny. For all the empire’s precocious advances, life expectancies ranged in the mid-20s, with infectious diseases the leading cause of death. But the array of diseases that preyed upon Romans was not static and, here too, new sensibilities and technologies are radically changing the way we understand the dynamics of evolutionary history – both for our own species, and for our microbial allies and adversaries.

The highly urbanised, highly interconnected Roman empire was a boon to its microbial inhabitants. Humble gastro-enteric diseases such as Shigellosis and paratyphoid fevers spread via contamination of food and water, and flourished in densely packed cities. Where swamps were drained and highways laid, the potential of malaria was unlocked in its worst form – Plasmodium falciparum – a deadly mosquito-borne protozoon. The Romans also connected societies by land and by sea as never before, with the unintended consequence that germs moved as never before, too. Slow killers such as tuberculosis and leprosy enjoyed a heyday in the web of interconnected cities fostered by Roman development.

However, the decisive factor in Rome’s biological history was the arrival of new germs capable of causing pandemic events. The empire was rocked by three such intercontinental disease events. The Antonine plague coincided with the end of the optimal climate regime, and was probably the global debut of the smallpox virus. The empire recovered, but never regained its previous commanding dominance. Then, in the mid-third century, a mysterious affliction of unknown origin called the Plague of Cyprian sent the empire into a tailspin. Though it rebounded, the empire was profoundly altered – with a new kind of emperor, a new kind of money, a new kind of society, and soon a new religion known as Christianity. Most dramatically, in the sixth century a resurgent empire led by Justinian faced a pandemic of bubonic plague, a prelude to the medieval Black Death. The toll was unfathomable – maybe half the population was felled.

The plague of Justinian is a case study in the extraordinarily complex relationship between human and natural systems. The culprit, the Yersinia pestis bacterium, is not a particularly ancient nemesis; evolving just 4,000 years ago, almost certainly in central Asia, it was an evolutionary newborn when it caused the first plague pandemic. The disease is permanently present in colonies of social, burrowing rodents such as marmots or gerbils. However, the historic plague pandemics were colossal accidents, spillover events involving at least five different species: the bacterium, the reservoir rodent, the amplification host (the black rat, which lives close to humans), the fleas that spread the germ, and the people caught in the crossfire.

Genetic evidence suggests that the strain of Yersinia pestis that generated the plague of Justinian originated somewhere near western China. It first appeared on the southern shores of the Mediterranean and, in all likelihood, was smuggled in along the southern, seaborne trading networks that carried silk and spices to Roman consumers. It was an accident of early globalisation. Once the germ reached the seething colonies of commensal rodents, fattened on the empire’s giant stores of grain, the mortality was unstoppable.

The plague pandemic was an event of astonishing ecological complexity. It required purely chance conjunctions, especially if the initial outbreak beyond the reservoir rodents in central Asia was triggered by those massive volcanic eruptions in the years preceding it. It also involved the unintended consequences of the built human environment – such as the global trade networks that shuttled the germ onto Roman shores, or the proliferation of rats inside the empire. The pandemic baffles our distinctions between structure and chance, pattern and contingency. Therein lies one of the lessons of Rome. Humans shape nature – above all, the ecological conditions within which evolution plays out. But nature remains blind to our intentions, and other organisms and ecosystems do not obey our rules. Climate change and disease evolution have been the wild cards of human history.

Our world now is very different from ancient Rome. We have public health, germ theory and antibiotic pharmaceuticals. We will not be as helpless as the Romans, if we are wise enough to recognise the grave threats looming around us, and to use the tools at our disposal to mitigate them. But the centrality of nature in Rome’s fall gives us reason to reconsider the power of the physical and biological environment to tilt the fortunes of human societies. Perhaps we could come to see the Romans not so much as an ancient civilisation, standing across an impassable divide from our modern age, but rather as the makers of our world today. They built a civilisation where global networks, emerging infectious diseases and ecological instability were decisive forces in the fate of human societies. The Romans, too, thought they had the upper hand over the fickle and furious power of the natural environment. History warns us: they were wrong.Aeon counter – do not remove

Kyle Harper is professor of classics and letters and senior vice president and provost at the University of Oklahoma. He is the author of The Fate of Rome, recently released, as well as Slavery in the Late Roman World, AD 275–425 and From Shame to Sin: The Christian Transformation of Sexual Morality in Late Antiquity. He lives in Norman, Oklahoma.

This article was originally published at Aeon and has been republished under Creative Commons.

A peek inside The Fate of Rome by Kyle Harper

HarperHere is the monumental retelling of one of the most consequential chapters of human history: the fall of the Roman Empire. The Fate of Rome is the first book to examine the catastrophic role that climate change and infectious diseases played in the collapse of Rome’s power—a story of nature’s triumph over human ambition. A poignant reflection on humanity’s intimate relationship with the environment, The Fate of Rome provides a sweeping account of how one of history’s greatest civilizations encountered and endured, yet ultimately succumbed to the cumulative burden of nature’s violence. Check out the trailer to learn more.

 

Kyle Harper is professor of classics and letters and senior vice president and provost at the University of Oklahoma. He is the author of Slavery in the Late Roman World, AD 275–425 and From Shame to Sin: The Christian Transformation of Sexual Morality in Late Antiquity. He lives in Norman, Oklahoma.

Kyle Harper on The Fate of Rome

Here is the monumental retelling of one of the most consequential chapters of human history: the fall of the Roman Empire. The Fate of Rome by Kyle Harper is the first book to examine the catastrophic role that climate change and infectious diseases played in the collapse of Rome’s power—a story of nature’s triumph over human ambition. The Fate of Rome provides a sweeping account of how one of history’s greatest civilizations encountered and endured, yet ultimately succumbed to the cumulative burden of nature’s violence. The example of Rome is a timely reminder that climate change and germ evolution have shaped the world we inhabit—in ways that are surprising and profound. Recently we interviewed Kyle Harper about his new book:

What is the fall of the Roman Empire?

The fall of the Roman Empire is one of the most dramatic episodes of political dissolution in the history of civilization—the long process that saw the fragmentation and disappearance of central Roman authority around the Mediterranean. In the second century, the Roman Empire was the world’s dominant superpower. One in four people on earth lived inside its borders. There was peace and prosperity on a scale never before seen. Five centuries later, Germanic kingdoms had conquered most of the west, and the Islamic caliphate was triumphant in most of the east. Population fell by maybe half, and there was less wealth, less trade, cruder institutions, and technological regression. The “fall of the empire” is a shorthand for all of the events and processes that led an empire that seemed invincible in the second century into a state of disintegration by A.D. 650.

What caused the empire to fall?

Historians have offered more than 200 answers, and obviously there was no single cause. But I argue that we have to allow environmental change—climate change and pathogen evolution—a dominant role. Human societies are deeply dependent upon their physical and biological environments, and these environments are radically unstable. The earth’s climate system has experienced significant climate change, even in the relatively stable epoch we know as the Holocene. And the biological environment—the set of organisms we share the planet with—has been wildly in flux, in ways that have redirected the course of human history. The empire was an intricate machine that depended on demographic and economic foundations, which fueled the army and the fiscal system. The Romans built their empire—unbeknownst to them—under unusually favorable climatic conditions. In a sense, their luck started to run out in the middle of the second century, with a sequence of climate change and new kinds of disease. Of course, these challenges did not spell the end of the empire. But the new reality became a part of the ongoing struggle to maintain their political dominance. Ultimately, the catastrophic pandemics that Rome suffered undermined the stability of the imperial machine.

How does new evidence change our answers to old questions?

Historians are the great unintended beneficiaries of at least two exciting new kinds of information about the past coming from the natural sciences. First, paleoclimate data. The need to understand global warming, and the earth’s climate system in general, has produced a treasure trove of new insights into the climate experienced by our ancestors. Two, genomic data. Thanks to the affordability of genome sequencing, we are learning a stunning amount about the story of the great killers of the past. The history of the bacterium that causes bubonic plague, Yersinia pestis, has really started to come into focus. It is a relatively young pathogen that evolved in central Asia and caused three great historical pandemics, the first of which afflicted the later Roman Empire in the reign of Justinian. This pandemic was probably as devastating as the medieval Black Death, carrying off something like half of the entire population. And, now, its genetic traces have been found in graves of the sixth century. What is most exciting, however, is the consilience—the leaping together—of new kinds of evidence and more traditional historical sources. I hasten to add that we historians are constantly finding new texts and documents and producing better understanding of old texts and documents. The ongoing, humanistic study of the Roman Empire is just as important as the thrilling scientific evidence. The pieces are starting to fit together.

How did diseases affect the course of Roman history?

All underdeveloped societies bore a heavy burden of infectious disease. Most deaths in the Roman world were caused by infectious disease. And the very success of the Roman Empire, paradoxically, exacerbated the endemic disease burden. The Romans were unhealthy. The dense urban habitats were unsanitary environments where low-level gastroenteric diseases were rampant. The transformation of the physical landscape facilitated the spread of mosquito-borne pathogens like malaria. The interconnection of the empire created a unified ‘disease pool’ where chronic diseases like tuberculosis and leprosy spread further than ever before. But, above all, the empire—and its massive trade contacts beyond the borders—opened the gate for newly evolved diseases, like smallpox, bubonic plague, measles, and possibly others—to enter the Roman world. The evolution of new, acute, directly communicable diseases created disease events—what are properly called pandemics—of a magnitude that had never been seen before. Three pandemics in particular—the Antonine Plague, the Plague of Cyprian, and above all the Justinianic Plague—shook the foundations of the Roman Empire.

Does the argument that “the environment did it” reduce the role of human factors?

There is simply no compelling way to describe the fall of the Roman Empire without an enormous allowance for human factors. The Empire was a human creation. Its fate was shaped by human choices and human structures. But I argue that we can actually understand the human element more deeply, and more sympathetically, with a deeper knowledge of the environmental dimensions of Roman history. The Romans were far from helpless victims of environmental catastrophe. They harnessed the power of the environment. They reshaped the disease ecology of the empire, with unintended consequences. They were resilient in the face of stress and strain. But we should not shy away from recognizing the power of nature. The physical and biological environment is an integral part of human life. There is really no separating human and natural factors in the story of Roman civilization.

What lessons can we learn from the fall of the Roman Empire?

The Romans have always captivated the imagination. The empire they built was truly extraordinary, in its scale and longevity and in the ways that its precocious development presaged modernity. And the dissolution of this empire has always been a poignant theme for reflecting on how even the greatest and most powerful of human constructions are ultimately transient. To be sure, our world is very different from the ancient world. We live long lives thanks to germ theory, public health, and antibiotic pharmaceuticals. Anthropogenic climate change is a greater risk than solar variability or volcanic winters. Still, we learn from the past because history is a humanistic discipline. We study the past and in the process emerge with a deeper, richer sense of what it means to be human. I hope that The Fate of Rome leaves its readers with a new sensibility toward the relationship between humanity and the environment. We care about the Romans because their civilization seemed to break free of some of the constraints that nature had imposed. But nature is cunning. Germs evolve. Surprises and paradox lurk in the heart of progress. The deep power of evolution can change the world in a mere moment. I hope the book sensitizes us to the awesome power of nature at all scales, from the microscopic to the global.

How did you decide to write a book on Rome and the environment?

I’ve wanted to write this book for a long time. I’ve been very fortunate to be around extremely creative people, including Michael McCormick, who was one of the first historians to insist that people in a traditionally humanistic field should pay attention to things like climate science, archaeological genetics, and bioanthropology. But only in the last couple of years has it even become possible to start pulling all the evidence together. The sequencing of the ancient genome of Yersinia pestis, for instance, is a watershed, as is the much clearer definition of the “late antique little ice age” achieved from tree rings and ice cores. All of this has happened in the last few years, and for those of us studying Roman history, it’s unbelievably fortunate. I think my book is the first to try to tie all this together with a robust model of how the Roman Empire actually worked, and what’s exciting is that over the next decade there will be lots of new evidence and plenty of revision to the story that I tell.

I also am lucky to be a Provost at the same time I’ve been working on this book. It means that I get to interact with atmospheric scientists, anthropologists, ecologists, microbiologists, and so on, on a daily basis. I have very generous colleagues who have helped me trespass across other disciplines. In turn, I hope my book shows why history is so valuable and so essential to other fields. Historians have a part to play in helping us understand everything from the landscape of global health to the chemistry of the atmosphere. In short, just as the natural sciences can help us understand human history better, so too can a deeper knowledge of the history of our species help us understand the natural world.

HarperKyle Harper is professor of classics and letters and senior vice president and provost at the University of Oklahoma. He is the author of Slavery in the Late Roman World, AD 275–425 and From Shame to Sin: The Christian Transformation of Sexual Morality in Late Antiquity. He lives in Norman, Oklahoma.

Oswald Schmitz: Reflecting on Hope for Life in the Anthropocene

This post by Oswald Schmitz, author of The New Ecology, was originally published on the March for Science blog. On April 22, PUP’s Physical and Computer Sciences editor Eric Henney will be participating in a teach-in the National Mall, focusing on the social value of direct and engaging scientific communication with the public. 

Springtime is a welcome reprieve from a prolonged cold winter. It is a time of reawakening when all kinds of species become impatient to get on with their business of living. We hear the trill of mating frogs, see leaves unfurl from their quiescent buds, and behold forest floors and fields unfold rich color from a dizzying variety of blossoming wildflowers. The energetic pace of life is palpable. It is only fitting, then, that we dedicate one spring day each year – Earth Day – to commemorate the amazing variety of life on this planet, and to take stock of the human enterprise and reflect on how our behavior toward nature is influencing its sustainability.

For many, such reflection breeds anxiety. We are entering a new time in Earth’s history—the Anthropocene—in which humans are transitioning from being one among millions of species to a species that can single-handedly determine the fate of all life on Earth. Many see the Anthropocene as a specter of doom, fraught with widespread species extinctions and loss of global sustainability, and attributable to humankind’s insatiable drive to exploit nature.

This view stems from the conventional idea that all living beings on Earth represent a heritage of slow evolutionary processes that occurred over millennia, culminating in the delicate balance of nature we see today. Many despair that humans are now jeopardizing the balance, as species will necessarily be incapable of coping with the onslaught of ever-new and fast-paced changes.

Iguana

An Aegean Wall Lizard, so named because of its evolved habit to live and hunt in rock walls constructed around crop fields in Greece. Individuals living on the walls have different limb morphology and mobility than counterparts of their species that are found within their original sandy habitats, demonstrating their capacity to adapt and thrive in human developed landscapes. Photo courtesy of Colin Donihue.

As an ecologist, I am torn by the changes I see. I have a deep and abiding respect for the amazing diversity of living organisms, their habits and their habitats. This ethic was shaped during my childhood when I was free to wander the natural environs of my hometown. I could go to those places any time of day, during any season: breathing, smelling, listening, observing, touching and tasting to discover nature’s wonders. That sense of wonder has endured. It’s what keeps me asking the probing questions that let me learn scientifically how species fit together to build up and sustain nature. It thus saddens—sometimes even maddens—me to see nature’s transformation in the name of human “progress.”

But as a scientist, I must admit that these changes are also fascinating. It turns out that rapid human-caused changes present much opportunity for new scientific discoveries. They force me to see and appreciate the dynamism of nature from fundamentally new vantage points. I find that nature can be more resilient than we often give it credit for, a fact that should inspire hope for a bright, sustainable environmental future in the Anthropocene.

Changing the mindset from despair to hope requires letting go of a deeply held notion that nature exists in a fragile balance, and that humankind has a persistent habit of disrupting that balance. Nature is perpetually changeable, with or without human presence. Life’s energetic pace, and the primal drive of all organisms to survive and reproduce, is what builds resilience in the face of change. We are learning how nutrients are perpetually transformed and redistributed by plant and animal species to sustain myriad ecological functions. These functions ensure that we have ample clean and fresh water, deep and fertile soils, genetic variety to produce hardy crops, the means to pollinate those crops, and the capacity to mitigate impacts of gaseous emissions, among numerous other services that humans rely on to sustain their health and livelihoods. Many species also can rapidly acclimate and even evolve within a mere span of a couple of human generations to cope with significant and rapid environmental change. Such adaptability allows many ecological systems to recover from human-caused disturbances and damages within the short time span of a human lifetime, no less.

This capacity for resilience is perhaps our most important evolutionary heritage. It is what gives hope for a sustainable future. The challenge of sustainability, then, is to engage with nature without eroding this capacity. The emerging science-based ethic of earth environmental stewardship can help on this front. It sees humans and nature entwined, where humans have obligations to one another mediated through their mutual relationships with nature.

Earth environmental stewardship strives to sustain nature’s resilience by protecting the evolutionary and ecological interdependence of all living beings and the physical environment. It strives for continuous improvement of environmental performance and human wellbeing through a commitment to use nature’s resources wisely and efficiently as dividends of resilient ecosystem functions. This means protecting entire ecosystems, not just their parts, and ensuring the development of sensible environmental policies and regulations to ensure that ecosystem services benefit all living beings now and in the future.

Effective earth environmental stewardship requires that we take deliberate interest in becoming scientifically informed about how our needs and wants are linked to our local environment and the larger world beyond. So on this Earth Day, it is perhaps fitting to reflect on and celebrate our amazing scientific achievements to understand the durability of nature and the wealth of opportunity it offers for a sustainable future in the Anthropocene.

Oswald J. Schmitz is the Oastler Professor of Population and Community Ecology in the School of Forestry and Environmental Studies at Yale University. His books include Resolving Ecosystem Complexity and The New Ecology: Rethinking a Science for the Anthropocene.

Natural disaster, experienced virtually

by Susan Scott Parrish

ParrishAs North Carolina towns like Goldsboro, Kinston, and Lumberton experience intense flooding long after Hurricane Matthew veered away from the coast, we are reminded again how disasters can take their own sluggish time. In the current case, it has taken days for intense rain water to move from inland streams to larger rivers, raising them to record heights.  “This is going to be a prolonged event,” announced North Carolina Governor Pat McCrory, after having signed an expedited Major Disaster Declaration for his beleaguered state.

My book, which is just about to be released with Princeton University Press, considers a different “prolonged event,” a “superflood” which took not three or four days to arrive, but rather months. The Flood Year 1927: A Cultural History is about the year-long disaster known colloquially as “The Great Mississippi Flood of 1927.” In a magnified version of the 2016 disaster, intense rains and snow fell for months throughout the upper branches of the river system, creating upstream flooding. Then these swollen tributaries all disgorged into the Lower Mississippi River simultaneously, evincing what one commentator at the time called a “sinister rhythm.”

If you have been following Hurricane Matthew and its path through Haiti, Florida and North Carolina, you understand that in the modern era, we experience most disasters virtually. I started thinking about this issue of virtual disaster consumption in the days surrounding, and months following, the New Orleans levee disaster of 2005 (“Katrina”). I began to wonder: how and why do disasters become publicly meaningful? Why do certain environmental catastrophes receive scant attention while others seem to place our national character on public trial? Is attention an unqualified good? How should we communicate with ourselves about disasters, especially now, in a time when human activity largely determines their makeup?

After much research, I came to realize that the first U.S. disaster to occur in a media landscape as well as in an industrialized, stress-bearing environment much like our own was the Mississippi Flood of 1927. The ways in which this flood went public, and then lost unified public meaning and indeed national attention, represent a fascinating case in modern disaster communication and consumption.

The 1927 flood was a humanly caused event. Deforestation, wetlands drainage, and monoculture farming throughout the Mississippi watershed in the late nineteenth and early twentieth century seriously reduced the storage capacity of its soil.  Moreover, designers of the flood protection system elected not to mimic an alluvial basin’s own mechanisms for holding and dispersing water in times of overflow. Engineers decided instead to impound the river within a towering levee system. Months of very intense rain and snowfall turned this precarious situation into catastrophe in the Lower Mississippi Valley as levees, and more levees, burst—one was even intentionally detonated to save the wealthy banking center and port of New Orleans. Over 600,000 people—mostly African American—were made homeless, land in seven states was inundated, thirteen major crevasses occurred, as many as 1,000 people died, and a year’s worth of cotton and sugar crops were ruined. The Red Cross was established, and the National Guard patrolled 154 “concentration camps” to house the evacuees but also to keep the Delta’s labor force in place.

Media technologies which produced this flood for a virtual audience were distinctly modern.  Wired telegraphy, aerial photography, recorded music, documentary film, a rapid and extensive AP service, and a brand new nationwide radio system were all put into use to transport this flood into homes in the US and around the world.  In the wake of World War I, moreover, governmental organizations knew how to use narrative and representational techniques to weld its citizenry into a unified mass. As communications theorist Harold Laswell put it in 1926, speaking of machine-age propaganda, “more can be won by illusion than by coercion.”

The flood of 1927 did seem to configure, at the flip of an all-powerful speaker switch, a coherent public audience.  FEMA did not yet exist and Congress refused to appropriate special funds, so the Red Cross had to commandeer the communications infrastructure of the nation to involve the public in the work and cost of relief. Newspapers, movie houses, vaudeville stages, and radio stations became vital pathways in a top-down, diffusive program of national coherence. It was not just any story though which made the “huge relief machine” hum, but a particular story about historical redemption. Because the course of the flood moved from north to south, retracing the 1863 river-borne assault on the Confederate strongholds of Mississippi and Louisiana, this flood had the peculiar power to make sixty-four-year-old history feel unfinished—to make it feel even biologically reenacted. When Herbert Hoover, the Commerce Secretary in charge of rescue and relief operations, first spoke to a national radio audience, he thus summoned memories of the Civil War. He imagined a new battle being waged between an invading “water enemy” and the people of “our South,” a “great army of unfortunate people.” Northern whites cast themselves this time around, in the words of The New York Times, as “an army of rescuers.” The Red Cross and its news outlets positioned this flood as a redemptive reenactment of the War between the States. This “illusion,” to use Laswell’s word, summoned national investment for about one month, and then public feeling split along regional and racial lines.

Sociologists at this time believed that disasters acted like helpful galvanic events to reset and repair a given society’s structural problems. The North’s disaster narrative, while it did symbolically bring accord, did nothing to actually address southern, and particularly, black southern, economic and political grievances.  White southerners came to express with great trenchancy their dissenting view that this calamity was neither natural nor redemptive, but was due to mainly northern environmental practices and the Federal government’s misguided levees-only policy. When they looked at the water destroying their crops, they saw Yankee water.

Advocates for southern black farm laborers likewise found old politics written all over the flood.  As conditions in the evacuee camps spelled for their black populations both forced labor and violently guarded movement, it seemed to many that slavery had returned to Dixie, and that northern institutions were abetting its reestablishment. W.E.B. Du Bois, Ida B. Wells, Walter White and others publicly decried this situation in The Crisis, The Chicago Defender, and The Nation.

Whites outside the South began to lose enthusiasm too for Hoover’s “reconstruction machine.” Valiant scenarios of rescuing southern brethren gave way to a regretful feeling that the South was forever an intractable “problem.” H.L. Mencken acerbically wondered why anyone would care about such a backward place of “tinpot revivals” and anti-intellectualism. And others just felt the story had grown dull. An editorial in The Nation averred that “people can stand only so much calamity. After a while it begins to pall, and finally it has no meaning whatever.” Another complained that the flood, lacking the dramatic unities of place and time, was aesthetically unsatisfying. And another observed that it is very hard to care for “a mud-besmattered mass of human beings” because only individual peril really moves an audience.

Once the flood slipped from the national headlines, it continued for some time to resonate in the black press and in the southern press. Eventually the event took up lodging in the imaginations, and the work of two of our major authors, who both happen to hail from Mississippi. Richard Wright and William Faulkner were young men living in or near the flood zone in 1927; each read Memphis’ paper, The Commercial Appeal, and its refutation of the dominant northern flood narrative. Wright was an avid reader of the black press coverage as well. For the next thirteen years, floods would seep into their fiction. While we tend to associate the Great War with modern narrative experimentation, for these two American authors, it was the 1927 flood which brought home the realization that the world was run on chance and risk, and, even more, that humans had made their physical and social worlds still more violently unpredictable.

In the 1920s, the Gulf South represented a leading edge of environmental peril. The region made manifest early what has since become more globally shared. Wright, Faulkner, and other attentive southern authors and performers of that day help us even now think about which stories, and which ways of bending language, comport most searchingly with the world of diffuse, chronic environmental risk in which we now live.

Susan Scott Parrish is a Professor in the Department of English and the Program in the Environment at the University of Michigan. Her book, The Flood Year 1927: A Cultural History, will be published this January.