A World Without Ice

Dr Henry Pollack, the author of A World Without Ice, is a geophysicist and an IPCC author. According to Al Gore, in the foreword, he is also “a scientist with the rare ability to engage ordinary people and to translate scientific ideas into everyday terms that are easy to understand”.

I couldn’t agree more. Pollack didn’t write A World Without Ice like a scientific journal, or like a textbook. Rather, he wrote it with the air of an enthusiastic science teacher introducing his students to new topics.

I was introduced to many new topics throughout the book – basic glaciology, the Earth’s geological thermostat, the Maunder Minimum – and I didn’t have to struggle to understand the terminology, or read anything twice. Pollack wrote with such clarity that learning new scientific topics felt almost effortless.

But absolutely top-notch were his metaphors. For example, this is how Pollack explains how the three factors of the Milankovitch cycles can combine to cause climatic change:

The composite is like listening to sound from an electronic synthesizer, which uses only three tones with different volume settings. The combination is usually some gentle cacophony, but from time to time there is some harmony between two of the tones, and on occasion with even one tone dominating, coming through loud and clear. The right combination of these Milankovitch factors sets the stage for snow accumulation at high latitudes and the beginning of an ice age.

Brilliant, no?

My one complaint about A World Without Ice was that Pollack tended to step too far away from his central topic of ice as a geological and climatic force. He ended up explaining everything that was even remotely related to ice, instead of sticking to what made his book unique.

For example, the North and South Poles are dominated by ice, so the first 30 pages were devoted to a history of polar exploration. Interesting stories, but not really necessary in a book about geology. It’s easy to find entire books about polar exploration if the reader is so inclined.

Later, when global warming came into the discussion, Pollack spent several chapters going through the basic lines of evidence for anthropogenic warming. I would wager that most readers of A World Without Ice are familiar with An Inconvenient Truth, or something similar, which has these explanations as its central purpose. Therefore, I don’t feel that running down this path well travelled is necessary for the audience at hand.

I feel that pieces of A World Without Ice could have been taken out, and the book as a whole would have actually benefited. So the next time I read it (and yes, I’m quite sure there will be a next time), I may not read the whole thing. I may skip the story of Captain Cook’s Antarctic voyage, or the explanation of the Keeling Curve. But I will read, many times over, the explanations of how ice is tied to geology, glaciology, and paleoclimatology. That’s what Pollack, this enthusiastic science teacher, intended the book to be about. And that’s what he does best.

TLC Book Tours is offering one free copy of A World Without Ice to a ClimateSight reader! The first person to correctly answer this question will be the winner:

What chapter of the IPCC AR4 did Dr Henry Pollack contribute to?

Leave your guesses in the comments. This contest is open to Canada and US readers only.

Essays CAN be Enjoyable!

I’ve been working on two different essays for school this past week. One is about the Grapes of Wrath. Bleccch. The other, however, was much more enjoyable. Compare three journalism texts on the same topic, see how they differ, and why.

I chose to cover the publication of the Kaufman et al study, with articles from the Winnipeg Free Press, New York Times, and Sydney Morning Herald. As my essay ended up being very relevant to the purpose of this blog, I thought I’d publish it here. Enjoy.

On September 4th, 2009, one of the foremost scientific journals in the world published a significant study regarding global warming. Scientists have known for years that the Arctic has been warming at an unusual rate, but, by putting the recent trend in historical perspective, the Kaufman et al study was able to show just how unusual. Nearly every major newspaper in the world covered the publication of the study, some more accurately than others. In this document, three articles, from Canada, the United States, and Australia, are examined.

This issue is not about the warming of the Arctic but, rather, a specific study regarding the warming of the Arctic. Therefore, it is fairly easy to gain an objective basis of the issue, simply by reading the study. The conclusions of the study can then be compared to the newspaper articles to see how well they summarize its findings.

The study in question, “Recent Warming Reverses Long-Term Arctic Cooling”, was published in Science magazine, which is one of the most reputable scientific journals in circulation. The study was in the field of paleoclimatology, which uses lake sediment, glacier ice, and tree rings to reconstruct past climates. Notably, this study was the first of its kind to reconstruct 2000 years of Arctic climate at a high resolution (temperature measurements which were only years or decades apart). Previous studies of this resolution only measured the Arctic climate of the past 400 years.

The results were striking. As expected from calculations of the Earth’s cyclical changes in orbit, the Arctic was cooling for the first 1900 years. The Holocene thermal maximum (warmest part of the interglacial) was between 6 000 and 10 000 years ago, and the Earth has been slowly moving toward another ice age ever since. However, in the past century, anthropogenic greenhouse gases caused this trend to sharply reverse. The rapid warming, at a rate of 1.4 C/century (compared to the previous cooling of -0.022 C/century), caused the Arctic to become even warmer than it had been at the beginning of the graph. The period of 1999-2008 was, therefore, the warmest decade in the past 2000 years.

It is important to note that the focus of the study was on the previous cooling trend, not the recent warming trend. As observational data is present for the past 100 years of Arctic temperatures, reconstructions were unnecessary. The recent data simply had to be inserted at the end of the process. Therefore, the rapid warming was only mentioned at the very end of the study, occupying less than one page out of four. The recent warming trend, especially in the Arctic, is already common knowledge in the scientific community. It is unsurprising that it took such a minor role in a paper which was, after all, about reconstructing climate from past centuries.

However, “Arctic warmer than in last 2000 years, new study finds”, printed in the Winnipeg Free Press, did not properly articulate this focus. The author, Bob Weber, called the study “groundbreaking”, which is very true, as it provides the first detailed reconstruction of Arctic climate going back farther than 400 years. However, Weber then devoted nearly the entire article to the recent spike in temperatures, implying that it was this recent anthropogenic trend, rather than the detailed reconstruction, which was so groundbreaking. For example, in the introductory paragraph, the study is referred to as providing “real-world evidence to back mathematical climate models that suggest greenhouse gases are behind global warming”. The authors of the study did compare the reconstruction to model simulations, but primarily in the context of the previous cooling, to see how well their data correlated with orbital calculations. They cared much less about how the observational warming data matched up with computer models, as that has been done countless times in other studies. Also, the models do not merely “suggest” that greenhouse gases are behind global warming. “Suggest” is likely too weak a word, especially for members of the general public, who are not well-phrased in the tentative language of science. In fact, there is not a single climate model which has been able to explain the recent warming without taking into account human activities. If there was, you can be very sure that everyone in the climate blogosphere would have heard about it far too many times from angry commenters.

A similar error is made when Weber writes, “The study says the fact that no other major variables changed about that time – there were no large volcanic eruptions, for example – suggests there could be only one culprit for the warming Arctic: carbon dioxide emissions that began increasing rapidly during the Industrial Revolution.” This error is somewhat more grievous than the last, as the study never made such a claim. The lack of an alternative explanation for the recent warming certainly is well known in the scientific community, but it is not covered in this particular study. Saying that it is implies that the study was focused on recent trends in temperature, rather than paleoclimatic reconstructions. Therefore, since the study is “groundbreaking”, the idea of an anthropogenic influence on climate is portrayed as groundbreaking as well – when, in actuality, scientists first began to examine the issue over a century ago. Svante Arrhenius’ claim, in 1896, that industrial emissions of carbon dioxide could one day warm the planet was groundbreaking. This study making such a claim was not.

However, changing the focus of the study was not the only error in the Free Press article. Weber made an incorrect choice of words which would have made anyone well-phrased in climatology cringe. When discussing how the study used lake sediment, glacier ice, and tree rings to reconstruct past climate, Weber stated that “all three methods are well-accepted ways of estimating weather.” It is really quite incredible that a science journalist could have gotten away with such an error, as the difference between weather and climate is covered in the first chapter of nearly every book about climate change. In reality, estimating weather with proxy reconstructions is virtually impossible, unless paleoclimatology were to advance to a point where proxy temperature measurements could be determined on a weekly scale. All that can be done – and all that really matters for our purposes – is to estimate climate, the standard conditions of temperature, precipitation, and variability in an area. Climate refers to a long period of time (classically 30 years). It is not affected by conditions of day-to-day weather. As it is, Weber’s assumption that the two words are interchangeable only serves to reinforce public confusion on their differences.

The article concluded with a statement about climate models, claiming that they “are often used by scientists to predict the effects of global warming and are just as often criticized by skeptics as mere speculation”. It is difficult to understand who Weber is referring to as “skeptics”. Does he mean the mobs of angry laypeople, omnipresent on YouTube, amateur blogging sites, and letters to the editor sections, nearly all of whom have little to no scientific background? If so, should we really trust them on the matter of how reliable climate models are? Do their shouts really count as criticism if they don’t know what they’re talking about? Alternatively, perhaps Weber is referring to actual scientists, who understand the physics, mathematics, and statistics of climate models, yet feel that they are little better than random guesses. We have no solid figure as to how many of these scientists exist worldwide, but minimal research shows that most, if not all, of them also hold the belief that humans are not affecting the climate. Such scientists make up roughly 3% of the climatological community (Doran and Zimmerman, 2009). They perhaps make up roughly a dozen worldwide. Giving them space in an article about a credible peer-reviewed paper reinforces yet another public misconception – that scientists are fairly equally split on whether or not humans are the cause of global warming.

Finally, the article was published on page A2 of the Free Press. Any regular reader of this newspaper will know that such a page is the most trivial in the issue. Page A2 is almost entirely covered by ads and indexes. There is a tiny space for an article, which is usually about someone’s lost parrot, or how a digital image of a squirrel is taking over the Internet. It is surprising that such a “groundbreaking” study was printed on this page, instead of in the “Science” or “World” section. What does it say about our mainstream media when an article of such scientific importance is squeezed into the easiest possible place to overlook? What does it say about our society?

Luckily, “Global Warming Could Forestall Ice Age”, printed in the New York Times, did not contain these errors. It was printed in the “Environment” section. Its focus was on the Earth’s glaciation cycles rather than the recent trends in temperature. It did not mention skeptics. The only similar mistake made was a mischaracterization of what was and was not stated in the study. Andrew Revkin, the author, writes that “summer temperatures in the Arctic region would be expected to cool for at least 4000 more years, given the growing distance between the Sun and the North Pole during the summer in the Northern Hemisphere, the study says.” The study did not say such a thing – it was common knowledge long before the study was written, since Milutin Milankovitch first calculated the Earth’s orbital cycles in 1941. Similarly, Revkin states that “the next [ice age], according to recent research, could be 20 000 or 30 000 years off discounting any influence by humans.” Again, this research is not recent. Portraying it as so implies that it is still somewhat shaky and unproven, which could lead the public to wonder if scientists really understand ice ages. Some individuals would be all too eager to claim that the Earth was simply approaching a new thermal maximum, which was causing the warming, not greenhouse gases.

A much more serious and troubling error appears later in the article. Revkin writes that “the ability to artificially warm the climate, particularly the Arctic, could be seen as a boon as the planet’s shifting orientation to the Sun enters a phase that could initiate the next ice age.” Anthropogenic greenhouse gases certainly could offset the next ice age. However, Revkin phrases this idea in a way which suggests that it is a good thing. Multiple misconceptions are present in this chain of logic. Firstly, Revkin assumes that warming is better than cooling. This is an easy assumption to make when you live at high latitudes, such as in the United States. However, from a broader, but still anthropocentric, worldview, it is the amount of change in climate which matters more than the direction it moves in. For example, warming might have some local benefits in North America and Russia, but it also causes subtropical drying, making agriculture in areas such as North Africa, Mexico, and Australia less and less viable. Cooling, in the other hand, allows the boreal forest to expand southward into richer soils, but it also makes the climates of high latitudes less conducive to human settlement. Both warming and cooling would have impacts on ocean and wind currents. Alternatively, perhaps Revkin believes that warming is more conducive to life on Earth. This assumption is incorrect, even at high latitudes – just look at the giant mastadons and other mammals which were present throughout North America during previous ice ages. Warming also causes desertification in some areas of the world, leading to water stresses that can threaten species. It seems obvious that the best situation for any species, including humans, is for the global climate to remain stable. Therefore, the magnitude of any change matters much more than whether it is warming or cooling.

So, let us look at the magnitude and rate of change in the transition to an ice age compared to the observed and expected warming. As the study states, the Arctic was previously cooling at a rate of     -0.022 C/century. This rate remains relatively steady as the Earth moves into a glacial state. However, the present warming is occurring at a rate of 1.4 C/century – 60 times faster, which is expected to accelerate dramatically as it progresses. Obviously, the current change in climate is much more dramatic than a descent into an ice age, and will cause much more stress for people as well as other life on Earth. Anthropogenic global warming is in no way preferable to an ice age.

Critically examining these two North American articles makes one lose faith in popular science journalism. However, when we look at the opposite corner of the world, Australia, a much more accurate article emerges. “Cooling trend of 1900 years reversed in decades” was published online through the Sydney Morning Herald. It is significantly shorter than the other articles, but contains none of the glaring scientific errors. In fact, the study is perfectly summarized in the first sentence of the article, which reads, “The Arctic was cooling for 1900 years because of a natural change in the Earth’s orbit until greenhouse gas accumulation from the use of fossil fuels reversed the trend in recent decades, scientists say.” In a remarkably concise fashion, Renee Schoof, the author, is able to convey the purpose, focus, and conclusions of the survey. The article goes on to explain how the Arctic would still be cooling if it weren’t for human activities, how global warming is expected to affect the Arctic first and foremost, and how warming in that area has serious implications for sea level rise and the stability of methane hydrates. Although the article was short, it lacked the editorial slant of the previous two pieces. One wonders if the Australian society is more accepting of the idea of anthropogenic climate change than North America is, as its media, at least in this instance, does a remarkably better job reporting it.

What does this analysis tell us about the reporting of science, particularly climate change, in North America? As we can see, it’s much worse here than it is in other parts of the world, as the two North American articles contained glaring errors, misrepresentation, and editorial slants which only served to perpetrate popular myths about climate change. The Australian article, in contrast, perfectly summarized the study. Are the Australians better informed, and therefore demand accurate journalism on climate change? Or are their media simply more responsible? Conversely, are North Americans blind to scientific situations which might have policy implications, and thus welcome journalism that downplays the status of the science? Or are the North American media corporations influenced by individuals and think tanks who wish the public to remain confused about whether or not climate change is a serious threat? Perhaps the two sides of the situation, the public and the media, feed off each other. The media influences what the public thinks, and the public expects the media to confirm their preconceived opinions. Once this feedback loop begins, it is difficult to stop. Hopefully it is not impossible.

The Source of the Ice Age Claim

An all-too-common claim people use to justify ignoring the widespread scientific agreement on climate change is, “The scientists were all predicting an ice age in the 70s, and that didn’t happen.”

Last year, a publishing climatologist, the highest category for an individual on our credibility spectrum, decided to investigate just how valid this claim was.

Dr Andrew Weaver is a Canadian climatology professor at the University of Victoria, the chief editor of the peer-reviewed Journal of Climate, a lead author on the 2nd, 3rd, and 4th IPCC reports,and the Canada Research Chair in Climate Modelling and Analysis. I think we can establish strong credibility for Dr Weaver’s statements.

In a 2008 article in the Ottawa Citizen, Dr Weaver explains how he searched through the enormous ISI Web of Science database for peer-reviewed studies claiming the world was heading into an ice age. He discovered that “there is not a single peer-reviewed original scientific study that argued this to be the case.” Only one paper mentioned the idea at all.

“The only paper that came close was one written by NASA scientists Ichtiaque Rasool and Stephen Schneider in 1971. A throwaway sentence at the end of their abstract noted:  “An increase by only a factor of 4 in global aerosol background concentration may be sufficient to reduce the surface temperature by as much as 3.5° K. If sustained over a period of several years, such a temperature decrease over the whole globe is believed to be sufficient to trigger an ice age.” Of course this statement is riddled with weasel words, assumptions and the hypothetical. Nevertheless, its scientific shelf life was only a few months before the assumptions underpinning the study were shown to be questionable.”

The peer-review process worked. The insufficient study was retracted. The idea of an ice age held hardly any agreement whatsoever in the scientific community, compared to the widespread agreement regarding the current climate change. Read the rest of Dr Weaver’s article if you’re interested in how scientists determined the cause of the slight drop in global temperatures post-WWII, despite the increasing levels of greenhouse gases.

Sadly, sources such as Time magazine, Newsweek, and the Globe and Mail (a major Canadian newspaper) got a hold of the recently discredited study. They liked the idea of controversial, attention-grabbing headlines that would engage their readers and, ultimately, bring money and attention to their writers. They published stories with titles such as, “Does man trigger trouble in the world’s climate cycle?” and “Another Ice Age?”

The public ate it right up. And now, 30 years later, this media-induced theory still persists.

At the same time that climatologists were studying the drop in temperatures, many of them were worried that the positive forcing of greenhouse gases would eventually outweigh the negative forcing of aerosols, volcanoes, and the solar minimum. Sources such as the National Academy of Sciences and science advisory committees to the President of the United States held this opinion. Check out this video by Peter Sinclair to see their exact statements (as well as a great clip from a 1958 Bill Nye-esque science show!). Dr Weaver’s article also mentions a 1975 article in the journal Science by Wally Broecker of the Lamont Doherty Earth Observatory.

With the ISI search tool, Dr Weaver was able to find one discredited study that mentioned an aerosol-induced ice age. When he searched the phrases “climate change” and “global warming”, he found 30 913 studies from the period 1965-2008. He speculates,

“That’s a lot of science and you can bet that if there were an Achilles heel to the theory of global warming it would have been discovered long ago.”

The 70s theory of an ice age simply cannot be compared to the current theory of anthropogenic warming. Their levels of support are completely opposite. The ice age theory was held by the extreme minority of publishing climatologists; the current climate change theory is held by the extreme majority.

In the 70s, the media misrepresented the science by overstating an almost non-existent theory. Currently, they are misrepresenting the science by suppressing an overwhelming theory and overplaying the opposition to it.

Personally, I’m going to refrain from basing my knowledge of climate change on the popular press. I suggest you do the same.