EIGHT
By the middle of the 1990s, the scientific consensus had jelled that humans were causing the climate to change. There was no ambiguity about soaring temperatures; a new and thoroughly alarming paradigm had emerged about how climate changes. If the emergent consensus in the scientific community had reached the public, perhaps there might have been meaningful action. The message did not reach the public, however, as various interests intervened to muddy and sometimes contradict the scientific message. The 1990s turned out to be a decade during which the science became clearer but the message more ambiguous.
For climate scientists, the 1990s were both a golden age and a period of tremendous upheaval. The ground shifted in the sense that a number of fundamental assumptions about climate change that held as the decade began were overturned by its end. During the same period, paleogeochemists and other researchers invented and refined tools that provided a more precise look forward as well as a new interpretation of past events, including the role of climate in human history and evolution.
It was a decade during which multiple paleoclimate investigations confirmed the hypothesis that climate could change globally with astonishing rapidity. It was a decade in which scientists began to realize that the great ice sheets were not as stable as had been assumed. It was also a decade in which scientists realized that the permafrost, which covers nearly a quarter of earth’s exposed land, was not as permanent as thought. This raised the prospect of runaway global warming as thawing released truly gargantuan amounts of greenhouse gases formerly trapped in ice and frozen soil.
It was also a decade in which the public and policymakers remained largely unaware of these developments.
The reasons were manifold. The public had only recently realized that what happened in the upper atmosphere—e.g., the ozone hole—could hurt us down here on earth. To get people to believe that there was another threat in the upper atmosphere caused by another set of invisible gases was asking a lot, particularly since this threat—global warming—actually sounded kind of nice.
Another reason, however, was that the dire new findings coming from climate scientists weren’t getting through to the public in a timely fashion. This was in part because the denier cohort began putting out disinformation in earnest. Another major reason, however, had to do with the way the scientific findings were disseminated.
The public does not read scientific journals. Neither do most policymakers. Rather, most people get their scientific information from the media, mainly from mainstream media, the networks, and radio. An item on the evening news might be a couple of minutes, and most articles in newspapers and the big-circulation magazines range from a few hundred to at most a couple of thousand words. This forces simplification. Worse, most mainstream press presumes (accurately) that the public has no background knowledge, so valuable space gets consumed retelling the basics of what the greenhouse effect is, leaving virtually no space or time for the actual scientific discovery. Moreover, in the interest of balance (with energetic prompting from the denial crowd), mainstream media, particularly in the 1990s, bent over backward to give space to contrarians long after the scientific consensus jelled.
With a few notable exceptions, the scientists didn’t help matters. There’s a cavernous gap between the demands of scientific rigor and the shorthand of mainstream journalism. Scientists hate to venture beyond the data, and most view oversimplification as a mortal sin. This makes for deadly dull and opaque quotes and confusion in the public, leading to an attitude that might be summed up as “What, you’re telling me that the heat wave may or may not be related to global warming? Come back to me when you’ve figured it out.”
If all these factors weren’t enough to defang the startling and alarming scientific discoveries of the 1990s, the decade saw the advent of one other filter that was formed to collect and disseminate the latest science on climate change but, instead, effectively doused whatever flames cutting-edge science sparked: the IPCC.
That was not the intention of its original promoters; quite the contrary. The Intergovernmental Panel on Climate Change emerged as a new institution, formed to gather, interpret, and find consensus on major issues involving climate change. A creation of the United Nations Environment Programme and the World Meteorological Organization, this massive undertaking became the primary, authoritative source that the media and policymakers turned to for the state of the science. Conceived with lofty ambitions to provide policymakers with the scientific consensus on the threat and possible paths forward, what it actually did throughout the 1990s and well into the first decade of the new millennium was to understate the problem and provide ammunition to those who would delay action on climate change. The IPCC’s very structure offered innumerable opportunities for mischief. Had this filter not existed between the public and the scientists, it’s possible that there might have been a better chance for meaningful action on climate change in the 1990s.
The mischief came both from governments and business and finance, which had largely ignored the issue through much of the 1980s. Toward the end of that decade a number of corporate interests began to realize that they needed to do something about climate change, not to lessen the threat, but to throw gum into the works of any efforts that might arise to actually do something about it.
The case of the IPCC shows the subtlety of the business community’s efforts to influence actions on climate change. The media, and thus the public, perceived the vast coalition as the voice of science, and for the most part that’s what it tried to be. Because it wanted to be a big tent, however, it opened the door for various nonscientific interests to weigh in, and this in turn allowed special interests first to apply direct and indirect pressure to shape the scientific consensus, and then call into question those parts of the consensus they had not been able to influence.
These interests had their own lobbying organizations. As noted, in 1989, the veterans of the ozone battle formed the Global Climate Coalition (GCC). Given its heavyweight membership, which then included the oil majors, the U.S. Chamber of Commerce, General Motors, and a who’s who of industry lobbying groups, the organization had great power in the halls of Congress. The IPCC had been formed a year earlier, and it presented industry with an opportunity to slow things down while seeming to be responsible corporate citizens.
The idea behind the IPCC was to bring together experts on all aspects of climate science, including social scientists, demographers, and others who could explore likely impacts, as well as representatives and policymakers from all nations. Their job: to assess “the scientific, technical and socioeconomic information relevant for understanding the risk of human-induced climate change.”
The devil himself could not have created a more cumbersome structure containing more conflicting agendas. At that time, the developing nations regarded climate change as a rich nations’ problem and rich nations’ responsibility. Powerful oil-rich countries had no interest in lessening dependence on fossil fuels and every interest in undermining the science. The corporate lobbyists who wanted to thwart any momentum to act on global warming may well have thought the IPCC was a gift from God.
The IPCC was also its own worst enemy. Apart from innumerable opportunities to introduce uncertainties and round the edges of various reports, the unwieldy nature of the IPCC virtually guaranteed that its reports would be tepid and bureaucratic. For one thing, the panel included thousands of participants, all of whom could weigh in on the reports. As Gus Speth put it to me, “You’ve got to remember the IPCC is the intergovernmental panel, not the interscientific panel or the interacademic panel.” Even if the IPCC had consisted entirely of scientists, the inherent caution of scientists to go beyond the data would have likely softened its findings. The IPCC, however, also included participants who actively worked to magnify uncertainties and undermine conclusions.
For instance, GCC representatives reviewing the Second Assessment Report of the IPCC took exception to some normal edits of parts of the report and used this purported “gotcha” moment to question the integrity of the process. The Wall Street Journal editorial page amplified their criticisms, and the deep-pocketed organization ran ads in major newspapers questioning the integrity of the IPCC process.
The government representatives didn’t help matters. Having them weigh in on a process that was supposed to provide the best scientific basis for a treaty to reduce the threat of climate change may have been necessary, but the bureaucrats, politicians, and functionaries proved to be a drag anchor on the process and the reports.
Consequently, for the first twenty years of its life, the IPCC gave as much fodder to those who would delay action as to those who demanded action. Things changed in the 2010s, but by then the damage was done. The IPCC reports, at least in their Executive Summary and Summary for Policymakers sections (the only sections that most people read), consistently underestimated or understated changes such as sea level rise, the contributions of melting permafrost, the state of the cryosphere, and other areas of concern. Because the IPCC reports were taken to represent the state of the art in science, they defused any sense of urgency about the threat and gave comfort and cover to those who would delay action.
The understatements and confusion spread by these massive reports were hardly the fault of the scientists involved. They were charged with the near-impossible task of understanding fundamental aspects of an immensely complicated dynamic even as it was unfolding. They also were being called upon to make predictions about future impacts even as the basic science itself was evolving.
The actual chapters of the reports were, for the most part, devoid of political influence. It was in the opening summaries, a distillation of the major findings in each report, that nonscientific influences had some impact. Unfortunately, these summaries were taken to be the scientific consensus, when in fact the language, and what was included, suffered from the influence of political, commercial, and foreign-policy agendas.
The first IPCC assessment was published in 1990. It was a massive document, but it’s a safe bet that few nonscientists read it, and those media types and policymakers who did mostly confined themselves to the Summary for Policymakers (or the press releases summarizing the Summary for Policymakers). Which means that for the public, the Summary for Policymakers became the consensus of the scientists even though it was not (the chapters themselves cautiously offered ranges of outcomes for different scenarios of climate change and its impacts).
This is an important distinction. Even as the Summary for Policymakers offered bland statements on a number of issues, the scientists themselves were finding evidence that the threat was far more imminent and dangerous than the headlines extracted from the summary. For instance, in his 1988 testimony before the Senate, James Hansen of NASA said it was 99 percent certain that the observed warming was caused by humans, not natural. Two years later, the IPCC summary held that the “observed increase could be largely due to this natural variability.” It went on to hold that “unequivocal” evidence of human-caused warming would not be clear for a decade or more, though it did say that by the time the evidence was unequivocal, the world would be locked into further warming.
In the 1990 IPCC report, the chapter dealing with permafrost offers projections for how much permafrost would melt as the globe warmed, as well as specific consequences of such melting. Yet the Summary for Policymakers offers the reassuring statement that no changes in the permafrost might be expected before the year 2100. With regard to the great ice sheets, the summary noted that studies had shown changes in the ice streams within the West Antarctic Ice Sheet but that “within the next century, it is not likely that there will be a major outflow of ice from West Antarctica due directly to global warming.”
All of this proved to be wrong—but not before these bland assurances took the wind out of any sense of urgency. Taken altogether, the explicit and subliminal messages of the summary were: “We’ve got time! No need to rush in! Much is unsettled!” Basically the opposite of a call to action. And an eager crowd of ideologues, vested interests, economists, and lobbyists were there to amplify the message.
Outside of the Executive Summary of the first assessment, science was progressing quite rapidly in the 1990s. The early part of the decade started off with a bang. Indeed, 1993 might be described as the year everything changed scientifically.
This was the year that the coordinated efforts of the European and American ice core projects published their findings in Nature, confirming that the Younger Dryas cooling started and ended far more abruptly than any model of past climate might have predicted. As physicist and science historian Spencer Weart put it, “How abrupt was the discovery of abrupt climate change? Many climate experts would put their finger on one moment: the day they read the 1993 report of the analysis of Greenland ice cores. Before that, almost nobody confidently believed that the climate could change massively within a decade or two; after the report, almost nobody felt sure that it could not.”
Despite the fact that Wallace Broecker had been writing about rapid climate change for well over a decade, these papers could be said to have launched a revolution in the understanding of how climate changes. It was these studies that prompted Richard Alley to remark that climate change that had once been regarded as a dial now seemed more like a switch.
Dramatic as these findings were, it still took the better part of a decade for this realization to move from a startling discovery to the new paradigm for understanding how climate changes. That said, a decade is still amazingly fast for a scientific revolution (twenty-eight years later, this revolution still hasn’t percolated through to most of the public). Other scientists rapidly filled out the picture.
That same year, for instance, Gerard Bond published an article in Nature showing that North Atlantic seabed sediment cores confirmed the signal of rapid climate change in the Greenland ice cores. A year later, Broecker, also publishing in Nature, proposed massive discharges of icebergs during glacial times as triggers for these rapid climate change events. The record showed that these events occurred on a millennial scale following the discharges. In honor of his colleague, he called these events “Bond cycles.”
Bond followed up the next year with an article in Science in which he argued that the record showed that these climate flips could occur in warm periods as well as during glacial spells. Working with another colleague at Lamont-Doherty, in 1997 Bond and Peter de Menocal published an article in the American Geophysical Union’s Eos offering evidence that abrupt shifts in climate extended into the Holocene, our present period, which previously had been thought of as extremely stable. That same year, Broecker connected these abrupt changes with disruptions of the thermohaline circulation, what he called the Great Ocean Conveyor, the global system of currents that, among other things, distributed heat to the North Atlantic, warming much of Europe. In that article, Broecker warned that if human-sourced greenhouse gas emissions triggered one of these disruptions of the ocean circulation, related atmospheric disruptions might lead to “widespread starvation.” He also noted that society would find it hard to adapt to a changed climate regime because such periods are characterized by “flickers” in climate as weather whipsaws back and forth from warm to cold and wet to dry as the system seeks a new equilibrium.
These are just a few of the scientific breakthroughs that advanced through the decade. By the close of the 1990s, climate scientists knew that Wally Broecker’s “angry beast” metaphor was dead-on and that past climates had been characterized by abrupt changes. They also had a far better idea of the interactions of the oceans and the atmosphere that might trigger these changes, and they knew these changes weren’t smooth. A study of climate whipsaws that characterized the transitions between these events led Kendrick Taylor and his colleagues at Nevada’s Desert Research Institute to coin the phrase “flickering climate.”
They also knew that big trouble was brewing with the West Antarctic Ice Sheet (WAIS), even if they weren’t sure when that trouble might arrive. WAIS is a marine ice sheet, which means it sits on bedrock instead of floating. Such sheets are inherently unstable. If the amount of ice they shed sufficiently exceeds ice accretion, it can set in motion a cascade of positive feedbacks that lead to the collapse of the sheet (and a complete collapse would raise global sea level by about 10 feet).
When I traveled to the WAIS in the fall of 1996, glaciologists were already seeing evidence that the daisy chain of feedbacks had begun. Ice streams—essentially rivers of ice within the ice sheet that move mass from the interior of the sheet to its edges—had already begun to flow more quickly. When I spoke with Ted Scambos, of the National Snow and Ice Data Center in Boulder, Colorado, he noted that when he looked at satellite imagery of the vast ice sheet, “I see an ice sheet in the process of collapse.” At that point, however, estimates of how long that process might take varied wildly.
In the 1990s, the assumption was that the WAIS had remained roughly in its present size for 120,000 years (subsequent research has shown that the ice sheet came close to collapsing at about the time of the Younger Dryas). It seemed audacious to speculate that a century of rising global temperatures might destabilize something so massive and persistent. At the same time, scientists were documenting ominous signs. It rained at America’s McMurdo Sound base for the first time that anyone could remember. The lake ice was thinning in the Dry Valleys, an area of Antarctica that was thought to have been relatively stable for more than a million years, and some of the ice shelves on the Antarctic Peninsula had begun to collapse.
These whispers of change would become a clamor over the next two decades. Even in the mid-1990s, the drumbeat of anomalies being recorded on the continent should have been sufficient to raise alarms. After all, the stakes were the potential inundation of coastal lands supporting several hundred million people.
Along with many other journalists, I wrote about these findings as they unfolded, in my case mostly for Time. Every one of the alarming trends uncovered in the 1990s has been subsequently confirmed; indeed, the worst-case scenarios of these years for issues ranging from sea level rise to incidence of extreme events are now either the conventional wisdom or, in some cases, the best-case scenarios of today. Still, the public remained unengaged. In part this was because there was a competing narrative on the science, one that gave plenty of cover for those who wanted business as usual to continue while looking as though they were seriously considering the issue.
The rising sense of alarm did not make it into the Executive Summary for the first IPCC assessment, and it did not make it into the Summary for Policymakers in the second IPCC assessment, published in 1995, seven years after James Hansen had told the U.S. Senate that it was certain that human influences were already affecting climate. Five years after its first assessment, the Summary for Policymakers said that there was a “discernible” human influence on climate beyond natural variation.
Updates on other climate-related threats were equally bland. The second assessment’s best estimate for sea level rise was actually 25 percent lower than the best estimate offered in 1990. While the first assessment had an extensive section on permafrost (even though the Executive Summary held that no changes were expected before 2100), the second assessment barely mentioned the issue. While the second assessment gave a range of 1 to 3.5 degrees Celsius warming for various scenarios, it also held that the oceans would delay when these “equilibrium” temperatures might be reached.
The second assessment did address rapid climate change in its chapters, noting the mounting evidence that changes in the past had occurred during human time scales, but then took the wind out of the sails of any sense of alarm with this sentence: “The relevance of past abrupt events to present and future climate would be more convincing if the suggested high climate variability in the Eemianfn1 was confirmed.”
The IPCC also muffed the crucial question of tipping points—the thresholds past which processes that would accelerate sea level rise (such as the collapse of ice sheets) or accelerate climate change (such as the melting of permafrost, which would release greenhouse gases and enhance warming) might happen. During the 1990s, the IPCC reports estimated such thresholds at 5 degrees Celsius or more, a warming that looked unimaginably far off in the future back then. More recent IPCC special reports have lowered that threshold to 2 degrees Celsius, and in some cases 1.5 degrees Celsius, thresholds that are very much in the near-term future. So, back when we might have done something about climate change, the most alarming possibilities were not of immediate concern; now, when we have vastly less time to avert further temperature rises, we are told that tipping points are right around the corner.
While the publication of the Greenland ice core studies in 1993 greatly accelerated the realization that many past climate shifts were violent and sudden, the Summary for Policymakers relegated this fundamental concept to a parenthesis in its concluding section headlined “There are still many uncertainties.” That section also had a one-sentence mention of a potential disruption of the thermohaline circulation in the North Atlantic, as well as the nonlinear nature of the climate system. Indeed, a look at the whole concluding section of the Summary for Policymakers underscores the unperturbed, leaden language of the document:
Many factors currently limit our ability to project and detect future climate change. In particular, to reduce uncertainties further work is needed on the following priority topics:
· estimation of future emissions and biogeochemical cycling (including sources and sinks) of greenhouse gases, aerosols and aerosol precursors and projections of future concentrations and radiative properties;
· representation of climate processes in models, especially feedbacks associated with clouds, oceans, sea ice and vegetation, in order to improve projections of rates and regional patterns of climate change;
· systematic collection of long-term instrumental and proxy observations of climate system variables (e.g., solar output, atmospheric energy balance components, hydrological cycles, ocean characteristics and ecosystem changes) for the purposes of model testing, assessment of temporal and regional variability and for detection and attribution studies.
Future unexpected, large and rapid climate system changes (as have occurred in the past) are, by their nature, difficult to predict. This implies that future climate changes may also involve “surprises.” In particular these arise from the non-linear nature of the climate system. When rapidly forced, non-linear systems are especially subject to unexpected behaviour. Progress can be made by investigating non-linear processes and sub-components of the climatic system. Examples of such non-linear behavior include rapid circulation changes in the North Atlantic and feedbacks associated with terrestrial ecosystem changes.
Imagine a different ending to that summary, one that stressed that every finding since the last summary suggested that climate shifts are violent and sudden, marked by whipsawing between hot and cold years and increased extreme events; that there were ominous signs of instability in the world’s largest marine ice sheet; that a substantial portion of the permafrost was in danger of melting and thereby releasing vast amounts of greenhouse gases that would in turn accelerate climate change. Imagine that this summary concluded that these indications were sufficiently dire that the world did not have the luxury of resolving scientific uncertainties before taking action to limit emissions of greenhouse gases.
That different summary could have been written—with scientific justification—but it wasn’t. No politician anywhere, reading the second assessment’s summary, was going to lead the charge to battle the fossil fuel lobby. Instead, the IPCC reports gave plenty of ammunition to anyone who wanted to delay action on climate change—a group that turned out to be practically everybody, ranging from the business community to the vast majority of world leaders.
There turned out to be two scientific clocks in the 1990s. It was a decade of tremendous breakthroughs in the understanding of the gears of the climate system, a decade that saw a rapid closing of the gap between the reality of climate change and our understanding of what was going on. This clock, however, was advancing much more rapidly than the scientific clock mediated by the IPCC.