The Day After Tomorrow: A Scientific Critique

The 2004 film The Day After Tomorrow, in which global warming leads to a new ice age, has been vigorously criticized by climate scientists. Why is this? What mistakes in the film led Dr. Andrew Weaver, Canada’s top climate modeller, to claim that “the science-fiction movie The Day After Tomorrow creatively violates every known law of thermodynamics”? What prompted Dr. Gavin Schmidt, NASA climatologist, to say thatThe Day After Tomorrow was so appallingly bad, it was that that prompted me to become a more public scientist”? What could an innocent blockbuster movie have done to deserve such harsh criticisms?

A New Ice Age?

The Day After Tomorrow opens with a new scientific discovery by paleoclimatologist Jack Hall, played by Dennis Quaid. After a particularly harrowing trip to gather Antarctic ice cores, he discovers evidence of a previously unknown climate shift that occurred ten thousand years ago. Since the film is set in the early 2000s, and ice cores yielding hundreds of thousands of years of climate data have been studied extensively since the 1960s, it seems implausible that such a recent and dramatic global climatic event would have gone previously unnoticed by scientists. However, this misstep is excusable, because a brand new discovery is a vital element of many science fiction films.

Jack goes on to describe this ancient climate shift. As the world was coming out of the last glacial period, he explains, melting ice sheets added so much freshwater to the Atlantic Ocean that certain ocean circulation patterns shut down. Since thermohaline circulation is a major source of heat for the surfaces of continents, the globe was plunged back into an ice age. Jack’s portrayal of the event is surprisingly accurate: a sudden change in climate did occur around ten thousand years ago, and was most likely caused by the mechanisms he describes. To scientists, it is known as the Younger Dryas.

The world’s ascent out of the last ice age was not smooth and gradual; rather, it was punctuated by jumps in temperature coupled with abrupt returns to glacial conditions. The Younger Dryas – named after a species of flower whose pollen was preserved in ice cores during the event – was the last period of sudden cooling before the interglacial fully took over. Ice core data worldwide indicates a relatively rapid drop in global temperatures around eleven thousand years ago. The glacial conditions lasted for approximately a millennium until deglaciation resumed.

The leading hypothesis for the cause of the Younger Dryas involves a sudden influx of freshwater from the melting Laurentide Ice Sheet in North America into the Atlantic Ocean. This disruption to North Atlantic circulation likely caused North Atlantic deep water formation, a process which supplies vast amounts of heat to northern Europe, to shut down. Substantial regional cooling allowed the glaciers of Europe to expand. The ice reflected sunlight, which triggered further cooling through the ice-albedo feedback. However, the orbital changes which control glacial cycles eventually overpowered this feedback. Warming resumed, and the current interglacial period began.

While Jack Hall’s discussion of the Younger Dryas is broadly accurate, his projections for the future are far-fetched. He asserts that, since the most recent example of large-scale warming triggered glacial conditions, the global warming event currently underway will also cause an ice age. At a United Nations conference, he claims that this outcome is virtually certain and “only a matter of time”. Because it happened in the past, he reasons, it will definitely happen now. Jack seems to forget that every climate event is unique: while looking to the past can be useful to understand today’s climate system, it does not provide a perfect analogue upon which we can base predictions. Differences in continental arrangement, initial energy balance, and global ice cover, to name a few factors, guarantee that no two climate changes will develop identically.

Additionally, Jack’s statements regarding the plausibility of an imminent thermohaline shutdown due to global warming fly in the face of current scientific understanding. As the world continues to warm, and the Greenland ice sheet continues to melt, the North Atlantic circulation will probably slow down due to the added freshwater. The resulting cooling influence on parts of Europe will probably still be overwhelmed by warming due to greenhouse gases. However, a complete shutdown of North Atlantic deep water formation is extremely unlikely within this century. It’s unclear whether an eventual shutdown is even possible, largely because there is less land ice available to melt than there was during the Younger Dryas. If such an event did occur, it would take centuries and still would not cause an ice age – instead, it would simply cancel out some of the greenhouse warming that had already occurred. Cooling influences simply decrease the global energy balance by a certain amount from its initial value; they do not shift the climate into a predetermined state regardless of where it started.

Nevertheless, The Day After Tomorrow goes on to depict a complete shutdown of Atlantic thermohaline circulation in a matter of days, followed by a sudden descent into a global ice age that is spurred by physically impossible meteorological phenomena.

The Storm

Many questions about the Ice Ages remain, but the scientific community is fairly confident that the regular cycles of glacial and interglacial periods that occurred throughout the past three million years were initiated by changes in the Earth’s orbit and amplified by carbon cycle feedbacks. Although these orbital changes have been present since the Earth’s formation, they can only lead to an ice age if sufficient land mass is present at high latitudes, as has been the case in recent times. When a glacial period begins, changes in the spatial and temporal distribution of sunlight favour the growth of glaciers in the Northern Hemisphere. These glaciers reflect sunlight, which alters the energy balance of the planet. The resulting cooling decreases atmospheric concentrations of greenhouse gases, through mechanisms such as absorption by cold ocean waters and expansion of permafrost, which causes more cooling. When this complex web of feedbacks stabilizes, over tens of thousands of years, the average global temperature is several degrees lower and glaciers cover much of the Northern Hemisphere land mass.

The ice age in The Day After Tomorrow has a more outlandish origin. Following the thermohaline shutdown, a network of massive hurricane-shaped snowstorms, covering entire continents, deposits enough snow to reflect sunlight and create an ice age in a matter of days. As if that weren’t enough, the air at the eye of each storm is cold enough to freeze people instantly, placing the characters in mortal danger. Jack’s friend Terry Rapson, a climatologist from the UK, explains that cold air from the top of the troposphere is descending so quickly in the eye of each storm that it does not warm up as expected. He estimates that the air must be -150°F (approximately -100°C) or colder, since it is instantly freezing the fuel lines in helicopters.

There are two main problems with this description of the storm. Firstly, the tropopause (the highest and coldest part of the troposphere) averages -60°C, and nowhere does it reach -100°C. Secondly, the eye of a hurricane – and presumably of the hurricane-shaped snowstorms – has the lowest pressure of anywhere in the storm. This fundamental characteristic indicates that air should be rising in the eye of each snowstorm, not sinking down from the tropopause.

Later in the film, NASA scientist Janet Tokada is monitoring the storms using satellite data. She notes that temperature is decreasing within the storm “at a rate of 10 degrees per second”. Whether the measurement is in Fahrenheit or Celsius, this rate of change is implausible. In under a minute (which is likely less time than the satellite reading takes) the air would reach absolute zero, a hypothetical temperature at which all motion stops.

In conclusion, there are many problems with the storm system as presented in the film, only a few of which have been summarized here. One can rest assured that such a frightening meteorological phenomenon could not happen in the real world.

Sea Level Rise

Before the snowstorms begin, extreme weather events – from hurricanes to tornadoes to giant hailstones – ravage the globe. Thrown in with these disasters is rapid sea level rise. While global warming will raise sea levels, the changes are expected to be extremely gradual. Most recent estimates project a rise of 1-2 metres by 2100 and tens of metres in the centuries following. In contrast, The Day After Tomorrow shows the ocean rising by “25 feet in a matter of seconds” along the Atlantic coast of North America. This event is not due to a tsunami, nor the storm surge of a hurricane; it is assumed to be the result of the Greenland ice sheet melting.

As the film continues and an ice age begins, the sea level should fall. The reasons for this change are twofold: first, a drop in global temperatures causes ocean water to contract; second, glacier growth over the Northern Hemisphere locks up a great deal of ice that would otherwise be present as liquid water in the ocean. However, when astronauts are viewing the Earth from space near the end of the film, the coastlines of each continent are the same as today. They have not been altered by either the 25-foot rise due to warming or the even larger fall that cooling necessitates. Since no extra water was added to the Earth from space, maintaining sea level in this manner is physically impossible.

Climate Modelling

Since the Second World War, ever-increasing computer power has allowed climate scientists to develop mathematical models of the climate system. Since there aren’t multiple Earths on which to perform controlled climatic experiments, the scientific community has settled for virtual planets instead. When calibrated, tested, and used with caution, these global climate models can produce valuable projections of climate change over the next few centuries. Throughout The Day After Tomorrow, Jack and his colleagues rely on such models to predict how the storm system will develop. However, the film’s representation of climate modelling is inaccurate in many respects.

Firstly, Jack is attempting to predict the development of the storm over the next few months, which is impossible to model accurately using today’s technology. Weather models, which project initial atmospheric conditions into the future, are only reliable for a week or two: after this time, the chaotic nature of weather causes small rounding errors to completely change the outcome of the prediction. On the other hand, climate models are concerned with average values and boundary conditions over decades, which are not affected by the principles of chaos theory. Put another way, weather modelling is like predicting the outcome of a single dice roll based on how the dice was thrown; climate modelling is like predicting the net outcome of one hundred dice rolls based on how the dice is weighted. Jack’s inquiry, though, falls right between the two: he is predicting the exact behaviour of a weather system over a relatively long time scale. Until computers become vastly more precise and powerful, this exercise is completely unreliable.

Furthermore, the characters make seemingly arbitrary distinctions between “forecast models”, “paleoclimate models”, and “grid models”. In the real world, climate models are categorized by complexity, not by purpose. For example, GCMs (General Circulation Models) represent the most processes and typically have the highest resolutions, while EMICs (Earth System Models of Intermediate Complexity) include more approximations and run at lower resolutions. All types of climate models can be used for projections (a preferred term to “forecasts” because the outcomes of global warming are dependent on emissions scenarios), but are only given credence if they can accurately simulate paleoclimatic events such as glacial cycles. All models include a “grid”, which refers to the network of three-dimensional cells used to split the virtual Earth’s surface, atmosphere, and ocean into discrete blocks.

Nevertheless, Jack gets to work converting his “paleoclimate model” to a “forecast model” so he can predict the path of the storm. It is likely that this conversion involves building a new high-resolution grid and adding dozens of new climatic processes to the model, a task which would take months to years of work by a large team of scientists. However, Jack appears to have superhuman programming abilities: he writes all the code by himself in 24 hours!

When he has finished, he decides to get some rest until the simulation has finished running. In the real world, this would take at least a week, but Jack’s colleagues wake him up after just a few hours. Evidently, their lab has access to computing resources more powerful than anything known to science today. Then, Jack’s colleagues hand him “the results” on a single sheet of paper. Real climate model output comes in the form of terabytes of data tables, which can be converted to digital maps, animations, and time plots using special software. Jack’s model appeared to simply spit out a few numbers, and what these numbers may have referred to is beyond comprehension.

If The Day After Tomorrow was set several hundred years in the future, the modelling skill of climate scientists and the computer power available to them might be plausible. Indeed, it would be very exciting to be able to build, run, and analyse models as quickly and with as much accuracy as Jack and his colleagues can. Unfortunately, in the present day, the field of climate modelling works quite differently.

Conclusions

The list of serious scientific errors in The Day After Tomorrow is unacceptably long. The film depicts a sudden shutdown of thermohaline circulation due to global warming, an event that climate scientists say is extremely unlikely, and greatly exaggerates both the severity and the rate of the resulting cooling. When a new ice age begins in a matter of days, it isn’t caused by the well-known mechanisms that triggered glacial periods in the past – rather, massive storms with physically impossible characteristics radically alter atmospheric conditions. The melting Greenland ice sheet causes the oceans to rise at an inconceivable rate, but when the ice age begins, sea level does not fall as the laws of physics dictate it should. Finally, the film depicts the endeavour of science, particularly the field of climate modelling, in a curious and inaccurate manner.

It would not have been very difficult or expensive for the film’s writing team to hire a climatologist as a science advisor – in fact, given that the plot revolves around global warming, it seems strange that they did not do so. One can only hope that future blockbuster movies about climate change will be more rigorous with regards to scientific accuracy.

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The Hockey Stick and the Climate Wars

Throughout all the years of public disputes about climate change, arguably no scientist has taken as much flak as Dr. Michael Mann. This mild-mannered paleoclimatologist is frequently accused of fraud, incompetence, scientific malpractice, Communism, and orchestrating a New World Order. These charges have been proven baseless time and time again, but the accusations continue. Dr. Mann’s research on climate change is inconvenient for those who wish to deny that current global temperatures are unusual, so he has become the bulls-eye target in a fierce game of “shoot the messenger”. In “The Hockey Stick and the Climate Wars: Dispatches from the Front Lines”, a memoir of his experiences, Michael Mann finally speaks out.

The story begins quite harmlessly: an account of how he became a scientist, from childhood curiosity to graduate work in theoretical physics to choosing climate science on a whim out of the university course calendar. For those who have followed Dr. Mann’s research over the years, there is some great backstory – how he met his coauthors Ray Bradley and Malcolm Hughes, the formation of the IPCC TAR chapter about paleoclimate, and how the RealClimate blog operates. This book also filled in some more technical gaps in my understanding with a reasonably accessible explanation of principal component ananlysis, a summary of millennial paleoclimate research before 1998, and an explanation of exactly how Mann, Bradley and Hughes’ 2008 paper built on their previous work.

Dr. Mann’s 1998 paper – the “hockey stick” – was a breakthrough because it was the first millennial reconstruction of temperature that had global coverage and an annual resolution. He considered the recent dramatic rise in temperatures to be the least interesting part of their work, because it was already known from instrumental data, but that part of the paper got the most public attention.

It seems odd for a scientist to downplay the importance of his own work, but that’s what Dr. Mann does: he stresses that, without the hockey stick, the case for climate change wouldn’t be any weaker. Unfortunately, his work was overemphasized on all sides. It was never his idea to display the hockey stick graph so prominently in the IPCC TAR, or for activists to publicize his results the way they did. Soon the hockey stick became the holy grail of graphs for contrarians to destroy. As Ben Santer says, “There are people who believe that if they can bring down Mike Mann, they can bring down the IPCC,” and the entire field of climate science as a result.

Michael Mann is an eloquent writer, and does a fabulous job of building up tension. Most readers will know that he was the target of countless attacks from climate change deniers, but he withholds these experiences until halfway through the book, choosing instead to present more context to the story. The narrative keeps you on your toes, though, with frequent allusions to future events.

Then, when the full story comes out, it hits hard. Death threats, and a letter full of suspicious white powder. Lobby groups organizing student rallies against Mann on his own campus, and publishing daily attack ads in the campus newspaper. Discovering that his photo was posted as a “target” on a neo-Nazi website that insisted climate change was a Jewish conspiracy. A state politician from the education committee threatening to cut off funding to the entire university until they fired Mann.

Throughout these attacks, Dr. Mann consistently found trails to the energy industry-funded Scaife Foundation. However, I think he needs to be a bit more careful when he talks about the links between oil companies and climate change denial – the relationship is well-known, but it’s easy to come off sounding like a conspiracy theorist. Naomi Oreskes does a better job of communicating this area, in my opinion.

Despite his experiences, Michael Mann seems optimistic, and manages to end the book on a hopeful note about improvements in climate science communication. He is remarkably well-adjusted to the attacks against him, and seems willing to sacrifice his reputation for the greater good. “I can continue to live with the cynical assaults against my integrity and character by the corporate-funded denial machine,” he writes. “What I could not live with is knowing that I stood by silently as my fellow human beings, confused and misled by industry-funded propaganda, were unwittingly led down a tragic path that would mortgage future generations.”

“The Hockey Stick and the Climate Wars” leaves me with a tremendous empathy for Dr. Mann and all that he has gone through, as well as a far better understanding of the shouting match that dominates certain areas of the Internet and the media. It is among the best-written books on climate science I have read, and I would highly recommend it to all scientists and science enthusiasts.

“The Hockey Stick and the Climate Wars” will be released on March 6th, and the Kindle version is already available.

A Vast Machine

I read Paul Edward’s A Vast Machine this summer while working with Steve Easterbrook. It was highly relevant to my research, but I would recommend it to anyone interested in climate change or mathematical modelling. Think The Discovery of Global Warming, but more specialized.

Much of the public seems to perceive observational data as superior to scientific models. The U.S. government has even attempted to mandate that research institutions focus on data above models, as if it is somehow more trustworthy. This is not the case. Data can have just as many problems as models, and when the two disagree, either could be wrong. For example, in a high school physics lab, I once calculated the acceleration due to gravity to be about 30 m/s2. There was nothing wrong with Newton’s Laws of Motion – our instrumentation was just faulty.

Additionally, data and models are inextricably linked. In meteorology, GCMs produce forecasts from observational data, but that same data from surface stations was fed through a series of algorithms – a model for interpolation – to make it cover an entire region. “Without models, there are no data,” Edwards proclaims, and he makes a convincing case.

The majority of the book discussed the history of climate modelling, from the 1800s until today. There was Arrhenius, followed by Angstrom who seemed to discredit the entire greenhouse theory, which was not revived until Callendar came along in the 1930s with a better spectroscope. There was the question of the ice ages, and the mistaken perception that forcing from CO2 and forcing from orbital changes (the Milankovitch model) were mutually exclusive.

For decades, those who studied the atmosphere were split into three groups, with three different strategies. Forecasters needed speed in their predictions, so they used intuition and historical analogues rather than numerical methods. Theoretical meteorologists wanted to understand weather using physics, but numerical methods for solving differential equations didn’t exist yet, so nothing was actually calculated. Empiricists thought the system was too complex for any kind of theory, so they just described climate using statistics, and didn’t worry about large-scale explanations.

The three groups began to merge as the computer age dawned and large amounts of calculations became feasible. Punch-cards came first, speeding up numerical forecasting considerably, but not enough to make it practical. ENIAC, the first model on a digital computer, allowed simulations to run as fast as real time (today the model can run on a phone, and 24 hours are simulated in less than a second).

Before long, theoretical meteorologists “inherited” the field of climatology. Large research institutions, such as NCAR, formed in an attempt to pool computing resources. With incredibly simplistic models and primitive computers (2-3 KB storage), the physicists were able to generate simulations that looked somewhat like the real world: Hadley cells, trade winds, and so on.

There were three main fronts for progress in atmospheric modelling: better numerical methods, which decreased errors from approximation; higher resolution models with more gridpoints; and higher complexity, including more physical processes. As well as forecast GCMs, which are initialized with observations and run at maximum resolution for about a week of simulated time, scientists developed climate GCMs. These didn’t use any observational data at all; instead, the “spin-up” process fed known forcings into a static Earth, started the planet spinning, and waited until it settled down into a complex climate and circulation that looked a lot like the real world. There was still tension between empiricism and theory in models, as some factors were parameterized rather than being included in the spin-up.

The Cold War, despite what it did to international relations, brought tremendous benefits to atmospheric science. Much of our understanding of the atmosphere and the observation infrastructure traces back to this period, when governments were monitoring nuclear fallout, spying on enemy countries with satellites, and considering small-scale geoengineering as warfare.

I appreciated how up-to-date this book was, as it discussed AR4, the MSU “satellites show cooling!” controversy, Watt’s Up With That, and the Republican anti-science movement. In particular, Edwards emphasized the distinction between skepticism for scientific purposes and skepticism for political purposes. “Does this mean we should pay no attention to alternative explanations or stop checking the data?” he writes. “As a matter of science, no…As a matter of policy, yes.”

Another passage beautifully sums up the entire narrative: “Like data about the climate’s past, model predictions of its future shimmer. Climate knowledge is probabilistic. You will never get a single definitive picture, either of exactly how much the climate has already changed or of how much it will change in the future. What you will get, instead, is a range. What the range tells you is that “no change at all” is simply not in the cards, and that something closer to the high end of the range – a climate catastrophe – looks all the more likely as time goes on.”

Climate Change Denial: Heads in the Sand

I recently finished reading Climate Change Denial: Heads in the Sand by Haydn Washington and Skeptical Science founder John Cook. Given that I am a longtime reader of (and occasional contributor to) Skeptical Science, I didn’t expect to find much in this book that was new to me. However, I was pleasantly surprised.

Right from Chapter 1, Washington and Cook discuss a relatively uncharted area among similar books: denial among people who accept the reality of climate change. Even if a given citizen doesn’t identify as a skeptic/contrarian/lukewarmer/realist/etc, they hold information about global warming at arm’s length. The helplessness and guilt they feel from the problem leads them to ignore it. This implicit variety of denial is a common “delusion”, the authors argue – people practice it all the time with problems related to their health, finances, or relationships – but when it threatens the welfare of our entire planet, it is a dangerous “pathology”.

Therefore, the “information deficit model” of public engagement – based on an assumption that political will for action is only lacking because citizens don’t have enough information about the problem – is incorrect. The barriers to public knowledge and action aren’t scientific as much as “psychological, emotional, and behavioural”, the authors conclude.

This material makes me uncomfortable. An information deficit model would work to convince me that action was needed on a problem, so I have been focusing on it throughout my communication efforts. However, not everyone thinks the way I do (which is probably a good thing). So what am I supposed to do instead? I don’t know how to turn off the scientist part of my brain when I’m thinking about science.

The book goes on to summarize the science of climate change, in the comprehensible manner we have come to expect from Skeptical Science. It also dips into the site’s main purpose – classifying and rebutting climate change myths – with several examples of denier arguments. I appreciate how up-to-date this book is, as it touches on several topics that are included in few, if any, of my other books: a Climategate rebuttal, as well as an acknowledgement that the Venus syndrome on Earth, while distant, might be possible – James Hansen would even say plausible.

A few paragraphs are dedicated to discussing and criticizing scientific postmodernism, which I think is sorely needed – does anyone else find it strange that a movement which was historically quite liberal is now being resurrected by the science-denying ranks of conservatives? Critiques of silver-bullet approaches to mitigation, such as nuclear power alone or clean coal, are also included.

In short, Climate Change Denial: Heads in the Sand is well worth a read. It lacks the gripping narrative of Gwynne Dyer or Gabrielle Walker, both of whom have the ability to make scientific information feel like a mystery novel rather than a textbook, but it is enjoyable nonetheless. It adds worthy social science topics, such as implicit denial and postmodernism, to the discussion, paired with a taste of what Skeptical Science does best.

Harmony: a New Way of Looking at our World

Even if you don’t have any intention of reading the new book by Prince Charles of Wales, it’s almost worth buying a copy just to admire it. Harmony: a New Way of Looking at our World is beautifully bound, with thick, glossy pages full of photographs that take you on a visual journey of the natural and architectural wonders of the world. Some, like the two-page spread of a humpback whale breaching, are joyful; others, such as the carcass of a young albatross, its digestive tract stuffed with plastic debris, are distressing.

The actual contents of the book were unique, but compelling. Rather than focusing on a particular issue and discussing it in depth, Prince Charles swept through just about every discipline you’d find in a modern university – agriculture, anthropology, architecture, art…and that’s only the A’s. This broad approach could easily have fallen into confusing disconnect, but he managed to connect each subject with what he referred to as a “golden thread”: a philosophical principle emphasizing the importance of following patterns seen in nature, and not trying to overwhelm or conquer it.

This approach is not really a “new way of looking at the world”, as the subtitle proclaims – in fact, it predates the dominant practice of Western society. For example, among indigenous civilizations that have modestly endured for many thousands of years, “not one…considers itself to be a master of creation”. Compare that to today’s industrialized society, which is only a few centuries old, and already views nature as a huge machine composed of independent parts which we can tweak at our will, rather than as a complex, dynamic system.

Prince Charles makes both emotional and scientific arguments to support his message, but he emphasizes the emotional ones first. I found this framing to be a turnoff, especially in the first chapter, which began, “This is a call to revolution. The Earth…is losing its balance and we humans are causing this to happen,” and continued from there. I couldn’t really take this narrative seriously, as I hadn’t yet heard his rational arguments, so the opening seemed far too dramatized. Perhaps others will find the initial appeals to emotion more effective than graphs and citations, but I was not impressed by them.

The meat of the book, however, was far better. Prince Charles explored a wide array of fascinating subjects that never managed to bore me. From the mathematical relationships found in the biosphere, to the importance of agricultural crop diversity in a changing climate, to the fascinating stream of engineering known as biomimicry, to the history of Islamic architecture…they may seem unrelated, but in fact all lead back to the importance of sustainability, in every sense of the word, and the incredible wisdom and beauty that can be found in nature.

The major flaw of Harmony, in my opinion, was the frequency of Prince Charles’ self-promotion. It seemed like nearly every second page contained a sentence similar to “(this particular problem) is very significant…and that is why I decided to start (some charity) to address it.” I think it’s wonderful that such a powerful and prolific figure is supporting projects for sustainability, but a better approach would have been to include an appendix of his charities at the end of the book. That way, the writing would have been less about him, and more about what he had to say.

There were also some obvious errors in the book, more serious than simple typos. 22 does not follow 13 in the Fibonacci Sequence, and the tilt of the Earth’s axis is not 24.5º (at least not at present). I expect these errors will be fixed in future editions.

The text’s discussion of climate change was fairly standard – think Al Gore’s slideshow, condensed into a few pages – but nonetheless very accurate and effective. There were some brief forays into paleoclimate which I enjoyed, too. Climate change was not the focus of this book, it was instead presented as a piece of a larger picture, but I appreciated the clarity with which it was addressed.

Although the scientific side of my mind is hyper-vigilant when I read nonfiction, I can relate to the deep affinity and spirituality people feel for the natural world. Nothing builds a sense of kinship like being out in the wilderness and recognizing how much smarter other species can be, in their own ways, than human beings. Nothing feels quite as healing as the quiet awe that strikes when a deer steps out onto the path ahead, or the joy and laughter that inevitably follow from watching songbirds. Nothing builds acceptance of the phenomenon of death like witnessing its omnipresence and necessity in any functioning ecosystem.

We could fill libraries with the economic, scientific, and health benefits of preserving nature in all its integrity. When it comes down to it, though, nature keeps us sane in the crazy world we have created for ourselves, and these emotional reasons are just as strong, if not stronger.

The Unofficial Climate Change Book Awards

Cross-posted from NextGen Journal

As an aspiring climate scientist, I have read dozens of books about climate change over the past few years. Here are my all-time favourites, which I present with Unofficial Climate Change Book Awards. (Unfortunately, the prizes consist entirely of bragging rights.)


Best Analysis of Future Scenarios
Climate Wars, by Gwynne Dyer
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Most of us are aware of how climate change will impact the world: more extreme weather, prolonged floods and droughts, dwindling glaciers and sea ice. In this book, renowned Canadian journalist and military historian Gwynne Dyer goes one step further, and explores how these physical impacts might affect geopolitical relations. Will India and Pakistan engage in nuclear warfare over clean water? Will the United States and Russia begin a “Colder War” over Arctic sovereignty? Many of the scenarios he writes about are, frankly, terrifying, and all have a frightening grain of plausibility to them. Read the full review


Best Introduction to Climate Science
The Discovery of Global Warming, by Spencer Weart
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Scientists overwhelmingly agree that human-caused climate change is underway, but instead of simply stating this conclusion, Weart tells the story of how it was reached: tracing the theory from the 1800s to today. This innovative approach to science education, combined with Weart’s elegant prose, makes the book a joy to read. It doesn’t feel like a textbook, although it contains as much information as one. Read the full review


Best Exposé
Climate Cover-Up, by James Hoggan and Richard Littlemore
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If scientists are so sure about the reality of anthropogenic climate change, why does so much of the public think that it’s natural/nonexistent/a global conspiracy? Why does the media present the issue as an equal-sided scientific debate? This confusion didn’t just happen by accident – it was deliberately constructed. Over the past two decades, lobby groups representing industries or ideologies that seek to delay action on climate change have engaged in a campaign to spread doubt about the reality of the problem. This book, rather than throwing around baseless accusations, methodically examines the paper trail of this widespread campaign. Reading Climate Cover-Up is an infuriating but absolutely necessary journey to take. Read the full review


Best Policy Discussion
Storms of my Grandchildren, by Dr. James Hansen
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James Hansen is possibly the most prominent climate scientist alive today, and that title is well-deserved. Throughout his career at NASA, he has frequently made discoveries that were ahead of his time. Dr. Hansen is a very intrinsic scientist who doesn’t enjoy being in the spotlight or talking about policy, but he wrote this book for fear of his grandchildren looking back at his work and saying, “Opa understood what was happening, but he did not make it clear.” Although he couldn’t resist slipping in a few chapters about the current frontiers of climate science, the bulk of the book is about policy, featuring compelling arguments for expanded nuclear power, a moratorium on coal, and a rising price on carbon. Read the full review


Best Canadian Focus
Keeping Our Cool, by Dr. Andrew Weaver
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Andrew Weaver is Canada’s top climate modeller, and a fantastic role model for science communication. This book gives a high-level, yet accessible, explanation of the mathematics of climate change – if you have some basic knowledge of calculus and statistics, you should be fine. However, what really makes this book stand out is its focus on Canadian climate journalism and politics, a rare quality in a field dominated by American research. We all know about George W. Bush’s track record of inaction, but what has Prime Minister Stephen Harper done (or not done)? High-profile studies exist on American media coverage of global warming, but how does the Canadian press compare? Read the full review


Best Insider’s Account
Science as a Contact Sport, by Dr. Stephen Schneider
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The late Stephen Schneider, who unexpectedly died last summer of a heart attack, is a true pioneer of climate modelling. He has been active in the field since the 1970s, when computers became fast enough to handle mathematical models. This memoir explains what it’s like to be a climate scientist, and how that has changed over the years. In the 70s, Schneider and his colleagues filled their mind with purely analytical questions, but today, they have to deal with the media, politicians, and hate mail as well. Science used to just be about science, but now it’s about communication as well. Read the full review


Most Gripping
Snowball Earth, by Gabrielle Walker
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Gabrielle Walker is a brilliant woman, as she possesses the ability to make a book about geology every bit as gripping as a murder mystery. Granted, Snowball Earth, a recent theory of climatic conditions during the Precambrian Era, is fascinating. In short, the continents were arranged in such a manner that the Earth would swing back and forth between “Snowball Earth” (frozen oceans and frozen land all over, even at the Equator) and “Hothouse Earth” (massive global warming from volcanic emissions of carbon dioxide). Until this period of massive climatic swings, the only thing that lived on Earth was unicellular goop…but immediately following the Snowball Earth cycles, complex life appeared. Many scientists don’t think this evolutionary timing was a coincidence. It’s possible that multicellular organisms, including us, only exist because of an accident of plate tectonics. Read the full review


If you would like to contest any of my decisions for these awards, please feel free to do so in the comments!

Merchants of Doubt

I waited a long time to read this book – in retrospect, too long. I have long been a fan of Naomi Oreskes; I believe she is a brilliant and sensible scientist with a compelling way with words. On the other hand, nothing depresses me more quickly than reading about those who deliberately spread confusion on climate change for political reasons. After a particularly battering year for climate science in the public eye, I want to make sure I stay sane.

However, Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming, by Naomi Oreskes and Erik Conway, was oddly comforting. How could it be so, you might ask, given the subject matter?

It’s a good question. The book traces several key players, such as Frederick Seitz, S. Fred Singer, Bill Nierenberg, and Robert Jastrow, in their fight against mainstream science. Many of them were physicists in the era of atomic bomb development, and nearly all had been deeply influenced by the Cold War – they were anti-Communist to the point of extremism.

This extremism soon extended into science: any new discovery that seemed to necessitate government action was vehemently attacked by Seitz et al. Whether it was the harmful health effects of smoking, second-hand smoking, or DDT, and the existence of anthropogenic acid rain, ozone depletion, or climate change, the same people used the same strategies to sow doubt in the public mind, delaying the cry for action. The algorithm was relatively simple:

  • construct arguments against the phenomenon, which scientists had already addressed and ruled out
  • widely publish these arguments in the popular press, rather than scientific journals
  • demand that the mainstream media be neutral and provide “equal time” for their side of the so-called controversy
  • attack the professional integrity of the scientists who discovered and studied the phenomenon; label them as frauds and/or Communists
  • claim that action on this issue would be the beginning of the “slippery slope to socialism”

It’s enough to anger anyone who has the least bit of sympathy for science. The authors say it best:

Why would scientists dedicated to uncovering the truth about the natural world deliberately misrepresent the work of their own colleagues? Why would they spread accusations with no basis? Why would they refuse to correct their arguments once they had been shown to be incorrect? And why did the press continue to quote them, year after year, even as their claims were shown, one after another, to be false?

History repeated itself many times over, within the course of just a few decades. The attack against climate science that we are currently witnessing is just a larger-scale rehash of the pro-industry, anti-Communist fight against epidemiology, environmental chemistry, and so on. Until now, few attempts have been made to connect the dots, but Oreskes and Conway present a watertight and compelling thesis in Merchants of Doubt.

The hopeful part came when I realized this: all of the previous issues that Seitz et al attempted to discredit were eventually addressed, more or less successfully, by the government, even if some of the public is still confused about the science. Restrictions and regulations on smoking, along with education regarding its harms, has made tobacco use a semi-stigmatized practice in my generation, rather than a near-universal activity. The Montreal Protocol was largely a success, and stratospheric ozone is on the rise. The world, at least so far, has managed to avoid nuclear warfare.

Climate change is undoubtedly a more inevitable and wide-ranging problem, as it strikes at the heart of our fossil-fuel based economy, and will probably surpass, both in rate and magnitude, any change our species has seen in the global environment. However, since the attack against climate science has tracked so closely with previous campaigns, I can’t help but hope it will eventually end the same way: with the public and the government realizing the problem and employing effective measures to address it. I know it’s probably not very scientific of me to make this connection, but hope doesn’t have to be rational to be effective.

Storms of my Grandchildren

I hope everyone had a fun and relaxing Christmas. Here’s a book I’ve been meaning to review for a while.

The worst part of the recent book by NASA climatologist James Hansen is, undoubtedly, the subtitle. The truth about the coming climate catastrophe and our last chance to save humanity – really? That doesn’t sound like the intrinsic, subdued style of Dr. Hansen. In my opinion, it simply alienates the very audience we’re trying to reach: moderate, concerned non-scientists.

The inside of the book is much better. While he couldn’t resist slipping in a good deal of hard science (and, in my opinion, these were the best parts), the real focus was on climate policy, and the relationship between science and policy. Hansen struggled with the prospect of becoming involved in policy discussions, but soon realized that he didn’t want his grandchildren, years from now, to look back at his work and say, “Opa understood what was happening, but he did not make it clear.”

Hansen is very good at distinguishing between his scientific work and his opinions on policy, and makes no secret of which he would rather spend time on. “I prefer to just do science,” he writes in the introduction. “It’s more pleasant, especially when you are having some success in your investigations. If I must serve as a witness, I intend to testify and then get back to the laboratory, where I am comfortable. That is what I intend to do when this book is finished.”

Hansen’s policy opinions centre on a cap-and-dividend system: a variant of a carbon tax, where revenue is divided evenly among citizens and returned to them. His argument for a carbon tax, rather than cap-and-trade, is compelling, and certainly convinced me. He also advocates the expansion of nuclear power (particularly “fourth-generation” fast nuclear reactors), a moratorium on new coal-generated power plants, and drastically improved efficiency measures.

These recommendations are robust, backed up with lots of empirical data to argue why they would be our best bet to minimize climate change and secure a stable future for generations to come. Hansen is always careful to say when he is speaking as a scientist and when he is speaking as a citizen, and provides a fascinating discussion of the connection between these two roles. As Bill Blakemore from ABC television wrote in correspondence with Hansen, “All communication is biased. What makes the difference between a propagandist on one side and a professional journalist or scientist on the other is not that the journalist or scientist ‘set their biases aside’ but that they are open about them and constantly putting them to the test, ready to change them.”

Despite all this, I love when Hansen puts on his scientist hat. The discussions of climate science in this book, particularly paleoclimate, were gripping. He explains our current knowledge of the climatic circumstances surrounding the Permian-Triassic extinction and the Paleocene-Eocene Thermal Maximum (usually referred to as the PETM). He explains why neither of these events is a suitable analogue for current climate change, as the current rate of introduction of the radiative forcing is faster than anything we can see in the paleoclimatic record.

Be prepared for some pretty terrifying facts about our planet’s “methane hydrate gun”, and how it wasn’t even fully loaded when it went off in the PETM. Also discussed is the dependence of climate sensitivity on forcing: the graph of these two variables is more or less a parabola, as climate sensitivity increases both in Snowball Earth conditions and in Runaway Greenhouse conditions. An extensive discussion of runaway greenhouse is provided, where the forcing occurs so quickly that negative feedbacks don’t have a chance to act before the positive water vapour feedback gets out of control, the oceans boil, and the planet becomes too hot for liquid water to exist. For those who are interested in this scenario, Hansen argues that, if we’re irresponsible about fossil fuels, it is quite possible for current climate change to reach this stage. For those who have less practice separating the scientific part of their brain from the emotional part, I suggest you skip this chapter.

I would recommend this book to everyone interested in climate change. James Hansen is such an important player in climate science, and has arguably contributed more to our knowledge of climate change than just about anyone. Whether it’s for the science, for the policy discussions, or for his try at science fiction in the last chapter, it’s well worth the cover price.

Thoughts from others who have read this book are welcome in the comments, as always.

Snowball Earth

Of all the books I have read about climate change, Snowball Earth, by Gabrielle Walker, is definitely one of the best – and it’s not even about the current climate change.

Part of what makes it so good is the style of writing. As the Los Angeles Times said about her later book, An Ocean of Air, “Walker has a Ph.D. in chemistry, but she writes like a poet.” And, indeed, after an education at Cambridge, Walker has spent most of her career as a science journalist. It’s sort of sad that this doesn’t happen more often. Usually, those who understand a subject best are not the ones who communicate it. Walker is the exception to this rule.

Take, for example, this passage about the history of life on Earth:

Stretch your arms out wide to encompass all the time on Earth. Let’s say that time runs from left to right, so Earth was born at the tip of the middle finger on your left hand. Slime arose just before your left elbow and ruled for the remaining length of your left arm, across to the right, past your right shoulder, your right elbow, on down your forearm, and eventually ceded somewhere around your right wrist. For sheer Earth-gripping longevity, nothing else comes close. The dinosaurs reigned for barely a finger’s length. And a judicious swipe of a nail file on the middle finger of your right hand would wipe out the whole of human history.

Another impressive aspect of Walker’s writing is her characterization. Wacky, stubborn, and exuberant scientists are brought to life. Instead of just hearing about their work and accomplishments, you feel like you’re getting to know them as people. She writes about arguing scientists particularly well. Arguing scientists are so much fun to read about – that’s one reason I loved The Lost World by Arthur Conan Doyle.

However, the best part of this book, by far, is the subject matter. The theory of Snowball Earth is possibly the most awesome thing I have ever heard about. Here’s how the story goes:

From what paleontologists can see preserved in fossils, complex life arose at a very specific point in prehistory: the end of the Precambrian. For several billion years before that, the only thing that lived on Earth was unicellular goop. But then, suddenly, all at once, complex organisms burst onto the evolutionary stage.

Something must have caused this dramatic appearance, and a series of scientists from the 1940s on – most prominently, Paul Hoffman – likely have discovered what. At the end of the Precambrian, there are signs of ice in rocks all over the world – scratches, rock deposits, everything that led Agassiz to discover the ice ages.

Because plate tectonics moves everything around so much, though, rocks were not necessarily formed at the location they sit today. Their magnetic field is what discloses their birthplace. Tiny bits of magnetic material, such as iron, line their field up with the Earth’s. The Earth’s magnetic field is perpendicular to the surface at the poles and parallel to the surface at the Equator, like this:

So, if a rock’s magnetic field is vertical, it was formed at the poles. If it is horizontal, it was formed at the equator. Incredibly, scientists found Precambrian rocks, with signs of ice, with horizontal magnetic fields. During that period of prehistory, the equator was covered in ice – and, therefore, the whole planet, because it’s not really possible to freeze the equator without freezing all the other latitudes too.

The scientists determined that, for several instances on the Precambrian, the continents were arranged in a way that was very conducive to ice-albedo feedback. With the smallest trigger, ice from the poles would creep across the temperature zones and meet at the equator. Frozen oceans, frozen land, the whole bit.

And now CO2 comes into the story. Volcanic eruptions naturally release carbon dioxide, but the amount is so small that the oceans have no trouble soaking them up – unless they’re frozen on the surface and cut off from the air. CO2 would gradually build up, in that case, and millions of years later, the greenhouse effect would be so strong that all the ice would melt and the planet would plunge into a state referred to as Hothouse Earth. Then the oceans would start absorbing all the extra CO2, and ice would reappear at the poles, and the cycle would begin again.

Many scientists believe that these Precambrian cycles of extreme heat and extreme cold provided such a strong pressure on organisms that natural selection was pushed to new boundaries. Complex life had an advantage in these extreme conditions, and it flourished. The most catastrophic climatic event our planet has ever experienced, in our knowledge, was what led to the evolution of multicellular organisms, and eventually, us.

It makes me feel very small, the same way that attempting to comprehend the vastness of the universe makes me feel very small. The life we see all around us only exists because of a series of coincidences. Human beings, one of the youngest of the millions of animal species that have ever existed, are alive because of continental drift lining things up in the right way. And who knows what would have happened if things had been slightly different?

A Quick Poll

I really enjoy books about climate change. When you’re as new to the subject as I am, they’re a great way to catch up on what is now common knowledge in the climate science community, and thus hasn’t been discussed recently in the peer-reviewed literature. I suppose I could also read the entire IPCC report to catch up, but that’s a little dry, to say the least.

Of course, this is assuming that the books actually reflect the peer-reviewed literature. Scientists in the field, like Andrew Weaver, Stephen Schneider, and Henry Pollack, write many of the popular books on climate change, so they’re pretty good about citing their sources. However, while tracking these down at the bookstore, one often encounters a lot of “Big Green and Global Warming Hysteria will Destroy our Freedoms and Create a Communist World Government!” publications.

All in all, though, I love this area of publishing. I frequently come out of the library with most of their climate science section under my arm, and now I’m frantically trying to finish reading before they realize how many times I’ve renewed some of the books. Exams got in the way of reading….

Here’s a quick poll – what’s your favourite book on climate change or climate science? Leave your responses in the comments, I’d love to read them.

I think I would place The Discovery of Global Warming, by Spencer Weart, at the top of my list – read my recent review of it here. It’s basic enough to appeal to people new to the issue, while detailed and comprehensive enough for scientists and long-time enthusiasts to enjoy. It contains as much information as a textbook, but is written like a compelling novel. Highly recommended to all.