12

Preseason Warm-Ups

Chris Landsea had a packed room to handle. It was late January 2006, and Landsea and fellow Gray alum Greg Holland were preparing to present back-to-back on a panel about hurricanes and climate at the annual meeting of the American Meteorological Society in Atlanta. It was standing room only; people lined the walls. Most of the audience members were scientists, along with a few reporters. Many of them expected, perhaps even hoped, to see fireworks.

Landsea and Holland wouldn’t be officially debating on this panel; they were merely slated to speak consecutively. In fact, a planned debate at this Atlanta meeting that was to feature Gray and Holland had been canceled by the conference organizers, who feared the showdown would get too nasty.

After the Webster paper came out, Holland had been up to Fort Collins, and he and his old teacher wound up in a shouting match. Not surprisingly, their memories of it differ. Gray’s joking aside, there don’t seem to have been actual “fisticuffs,” but it’s apparent nonetheless that they had a falling out.

“I said, ‘Greg, you need a tongue-lashing,’” Gray remembered. And then, according to Gray, Holland “gave me hell.” Why, Holland wanted to know, hadn’t Gray stood by his own student as the hurricane-climate debate unfolded? “He came in the office and we really argued,” said Gray. “He said he is going to come back the next day and show me data. He never showed.” In Holland’s recollection (shortly after it happened), the exchange sounds a bit different. “Bill and I have argued about scientific issues from day one,” he said. “That’s what scientists do. The unfortunate thing is that, in the last twelve months, it’s become personal, and I have to say, it’s become personal entirely on one side.”

The public debate scheduled for the Atlanta meeting wasn’t the only one undermined by a scientific conflict that, under the combined influences of politics, the media, and the weather, had grown too frictional. Two other proposed events had to be reorganized as Emanuel, Holland, Webster, and Curry vowed to no longer appear alongside Gray.

The meltdown happened in the context of planning another conference panel, for the American Meteorological Society’s more specialized Hurricanes and Tropical Meteorology meeting, slated to take place in April 2006 in Monterey, California. In November 2005, Elizabeth Ritchie, a University of New Mexico hurricane expert charged with chairing the meeting, had invited Gray, Webster, Emanuel, Landsea, and Max Mayfield to participate in a panel discussion that sounded like the conference’s main draw. Ritchie merely said the panel would address the “causes” of the dramatic 2005 Atlantic hurricane season. But given who’d been invited, global warming would clearly take center stage.

Webster and Emanuel quickly expressed concerns. Emanuel recalled his debate with Gray at a Hurricanes and Tropical Meteorology meeting in 2000. “While this sort of thing plays well with certain tropical groupies and with the press, I think it does lasting damage to the image of our profession,” he wrote. “If Bill Gray is prepared to act professionally then we will see,” added Webster, complaining that Gray had accused his team of “all types of malfeasance including cooking the data to get money.”

Quoting all this, Gray then fired back a lengthy e-mail to the group, stating that he would be happy to sit on the panel so long as he was given an assurance that Emanuel and Webster “will behave themselves and try not to make derogatory and paranoid statements about me as contained in their recent e-mails.” Gray went on to suggest that the two scientists had indeed come up with their data to advance their careers. (As he put the point in a later e-mail: “Had their data showed no TC increase or a TC decrease, they would not have had papers of media interest or justification for further grant support for research on this topic.”) Gray signed off by invoking a disciplinary divide and his own special expertise as a card-carrying hurricane scientist: “How were Emanuel and Webster et al. able to see trends in the global data that the rest of us long-time TC researchers presently working on these same data sets do not find?”

Ritchie quickly swooped in and tried to save the panel. She promised there would be special “rules” to govern the discussion and keep everything above the belt—rules to be enforced by moderator and longtime hurricane scientist Russell Elsberry, who like Gray was a former student of Riehl. And she emphasized that she wanted everyone she had originally invited to participate: “The media know and respect all of you, and the panel will be seen to be incomplete without any of you.” But it was too late. Emanuel and Webster refused to sit on the panel with Gray. “To disagree with science is one thing but to question motivation and accuse one of ethical malfeasance is another,” wrote Webster.

Ritchie wasn’t giving up. She suggested disinviting Gray and instead asking someone like Gray’s student Johnny Chan—a professor at the City University of Hong Kong, an expert on Northwest Pacific typhoons, and a skeptic of the Webster research—to participate. Apparently she then did so, because in a later e-mail to the group Gray suggested he had been “blackballed” and added to Ritchie: “There is still time to backtrack.”

At this point Landsea—who had started off the thread with a joking message promising not to “throw anything or hit anyone ;-)” at the debate—stepped in. “Bill, please, stop,” he wrote. “Liz had no choice but to drop you from the program because of your public accusations,” he continued. Now, Landsea said, he would have to “carry the banner” in Gray’s absence.

And so in a sense Landsea became the group’s diplomat. Not only would he have to keep explaining why the new studies’ findings about hurricanes and global warming weren’t reliable. He’d have to do so without triggering another meltdown.

 

When the Atlanta meeting finally rolled around, Landsea seemed up to the challenge. He started the panel off smoothly, joking that as first speaker he would be allotted twenty-five of the panel’s thirty minutes, and Holland, who would follow, would get five.

A surge of laughter diffused the tension in the room, and Landsea launched into his presentation (which he limited to a reasonable fifteen minutes). First he underscored the discrepancy between Knutson’s modeling work—which suggested that although hurricanes should intensify due to global warming, that intensification shouldn’t be detectable yet—and the data-based studies of Emanuel and the Webster group. “Theory and models,” Landsea claimed, gave grounds for doubting the latest data (not that Landsea trusted the models, either).

Landsea’s chief argument, however, lay with the data itself. Especially when it came to the Webster study, Landsea said, satellite records of hurricane intensities weren’t dependable enough to support its striking conclusions. In particular, he noted that the application of the Dvorak cloud pattern-recognition technique, which is regularly used to evaluate hurricane intensity from satellite pictures and has been especially relied upon in basins lacking aircraft reconnaissance, had changed over time. Landsea contended that the strong trend of storm intensification observed in the Webster study probably reflected a change in techniques for measuring hurricanes, rather than a change in hurricanes themselves.

Satellites, Landsea explained, had grown more numerous over time, and their images had increased in resolution. The Dvorak method itself had matured into an infrared technique in 1984, meaning it could be used at night as well as during the day. Landsea even flashed satellite images of a few North Indian basin cyclones from previous decades that, he said, would have been classified as stronger storms in a later era. Therefore, Landsea concluded, the “problem is with the data sets.”

Unlike Gray, Landsea never once in the discussion questioned the existence of global warming. Nor did he dispute that evidence of it was apparent in the oceans (a subject Knutson would discuss at the meeting the next day) or even in the specific ocean regions that serve as hurricane breeding grounds. Rather, he sought to set observations of hurricane intensities in historical context and explain how they’d grown much more reliable over time.

Another way Landsea makes this point is to contrast hurricane intensity measurements at fifty-year intervals. The 1900 Galveston hurricane, he explains, had its central pressure sampled only once—by a ship. In 1954, Hurricane Carol had its intensity measured seven times, still not nearly enough for us to know how strong it was during significant parts of its lifetime. (Carol, which knocked a tree onto Jule Charney’s car at Woods Hole, isn’t even officially classified as a hurricane in Massachusetts, although Landsea thinks it ought to be.) Hurricane Wilma in 2005, by comparison, had its pressure and winds measured 280 times over the storm’s lifetime. So it’s far more likely that Wilma was observed at or around peak intensity.

Without a doubt, Landsea had articulated a serious criticism. Yet he had not directly disproved the work of Emanuel and Webster; he had merely given reasons to doubt their conclusions. And Emanuel and Webster’s team had counterarguments. While acknowledging weaknesses in the historic “best track” hurricane databases, Emanuel also ventured that they ought to be little more than random errors, in which storm intensities were overestimated or underestimated in roughly equal proportion. Webster and colleagues, meanwhile, responded in Jerry Maguire fashion: Show me the money. Given the size of the trend they claimed to have uncovered (a near doubling of Category 4 and 5 hurricanes), only the reclassification of a very large number of storms would significantly undermine their results. In the meantime, they wrote, “There is no evidence that we cannot, for the vast majority of hurricanes since 1970, distinguish between category-4 and -5 hurricanes and category-1 and -2 hurricanes.”

Interpretations of the flawed hurricane data, then, took on a half-full/half-empty aspect. Landsea looked at the data and saw reasons to doubt. Webster and colleagues looked at the data and saw reasons to worry.

Holland followed Landsea on the panel. On paper, the two scientists sound like twins, and they share the distinction of being Gray’s only students to have won the same two American Meteorological Society awards while studying under him. Yet in person the contrast couldn’t be sharper. Landsea is tall and clean-shaven, blundy American in speech and style; in suit and tie, he looked ready to meet the president (as, in fact, he later would). Holland is shorter and thick-bearded, and talks much more rapidly, with a strong accent. He dressed in a rumpled academic style—blazer but no tie.

Holland began on a personal note: Since he’d moved to the United States, he had grown acutely interested in the Atlantic and its hurricanes. And so he sought to defend his team’s controversial results and, simultaneously, to reconcile them with preexisting hurricane-intensity theory (which he and Emanuel had done much to create). One reason we’ve seen more intense storms in the Atlantic, Holland argued, is that the seedbeds of Atlantic hurricanes had changed. The storms had been forming farther to the south over warmer waters, a phenomenon that had created a higher proportion of Cape Verde-type storms. “The whole damn lot have moved towards the equator and become more intense,” Holland said. But theoretical and modeling studies of hurricane intensity, he pointed out, hadn’t been designed to analyze such a shifting storm population.

Holland also challenged the notion that a natural oceanic cycle could explain the warming Atlantic, which had fostered these stronger hurricanes. Given all the research showing that human activities had been driving a global ocean-warming trend, he stated, there was “no way any rational being can say that high SSTs in the North Atlantic are entirely natural.”

Emanuel didn’t attend the 2006 Atlanta meeting, but like Holland, he was busy trying to reconcile his prior theory with his new observations. In particular, Emanuel was investigating why the apparent response to global warming seemed different in the Atlantic than in the Northwest Pacific, the other basin he’d studied. For the Atlantic, he found that four key factors controlling how much power hurricanes dissipate—sea-surface temperatures, wind shear, trade-wind speed, and temperatures in hurricanes’ outflow region (the tropopause)—all seemed to be changing in a synchronized fashion. But for the Northwest Pacific, the four were “doing their own thing.” If warming oceans were having a more pronounced effect in one basin than in another, the response of hurricanes to global warming might be far more complicated than originally supposed.

If the scientists were finding that the link between hurricane intensity and a warming world was a tough riddle to crack, they were also learning that dealing with a swarming media—especially after the disastrous 2005 hurricane season—could be fraught with peril.

Prior to 2004, journalists had generally been content to discuss hurricane-climate linkages episodically, usually in the context of land-falling storms during hurricane season. Then they would largely drop the subject until the next storm showed up. After the 2004 and 2005 hurricane seasons, however, the public wanted to know what the hell was going on with the atmosphere and the oceans, and this appetite continued to drive news even in the absence of storms. Without dramatic weather or fresh scientific publications on hurricanes and global warming to report on in early and mid-2006, reporters turned to novel story angles. Not only did they fixate on the budding scandals at NOAA, but they began haunting scientific conferences and reporting on the increasingly nasty and personal nature of the debate between Gray and his adversaries. It was a form of journalism that the scientists themselves despised, because it suggested that there might be more driving their stances than an objective assessment of the data—and because it moved the coverage toward an emphasis on drama and conflict.

The trend was epitomized by a Wall Street Journal page-one story by Valerie Bauerlein, published in early February 2006. “Cold Front: Hurricane Debate Shatters Civility of Weather Science,” screamed the headline. Reporting on the American Meteorological Society meetings in Atlanta, Bauerlein opened her story with the canceled Holland-Gray panel and put a heavy accent on character and conflict. At the Atlanta conference, she wrote, the reasons for the deadly 2005 hurricane season were “almost too hot to handle.” She soon quoted Gray saying that Webster’s coauthor Judith Curry “just doesn’t know what she’s talking about,” and then quoted Curry saying that Gray suffered from “brain fossilization.”

Clearly, if the weather and ongoing scientific research did not provided anything juicy, journalists would be looking elsewhere for the fodder they needed.

 

The 2006 global hurricane season began where it always does, in the Southern Hemisphere, which experiences summer first. In late February, the South Atlantic hosted what looked like another tropical disturbance, though certainly no Catarina this time. The storm remained organized for only a few hours before getting blown apart by shear. Still, its 35-mile-per-hour winds were enough to prompt leading meteorology blogger Jeff Masters to suggest that the time had come to consider a naming system for South Atlantic cyclones and to speculate about whether climate change might be systematically weakening wind shear in the region. Two weeks later, another weak but tropical-looking disturbance showed up briefly in the South Atlantic.

Meanwhile, the Australian region was already in the midst of a terrible year for severe tropical cyclones, as the strongest hurricanes there are called. Australia can be hit by storms forming in either the South Indian or Southwest Pacific basins (which merge together more or less seamlessly as one progresses farther east). The intensity scale used to classify these cyclones differs from the one used in the United States, but translated into Saffir-Simpson categories, the 2005–2006 Australian season saw either two or three Category 4s (Bertie-Alvin, Floyd, and possibly Larry) and two Category 5s (Glenda and Monica). The most destructive of them, Larry, formed in the eastern Coral Sea and slammed the populous northern coast of Queensland near Innisfail on March 20, leaving half of the homes damaged. At Silkwood, which received the worst of the storm, the figure was much worse: 99 percent of homes lost their roofs or suffered some form of assault to their structural integrity.

Larry—and the difference between the Australian and Saffir-Simpson hurricane scales—did provide for some comic relief, however. In April 2006, Time magazine ran a cover story on global warming. “Be Worried. Be Very Worried,” it intoned. Announcing that “the crisis is upon us,” the lead article then continued:

 

It certainly looked that way last week as the atmospheric bomb that was Cyclone Larry—a Category 5 storm with wind bursts that reached 180 m.p.h.—exploded through northeastern Australia. . . . Disasters have always been with us and surely always will be. But when they hit this hard and come this fast—when the emergency becomes commonplace—something has gone grievously wrong. That something is global warming.

 

Although there’s some dispute about its strength, it seems clear that Larry was either a Category 3 or possibly a Category 4 storm by the hurricane scale Americans are used to. According to the National Climatic Data Center, the storms maximum wind gusts only reached about 145 miles per hour (and maximum sustained winds were closer to 115 miles per hour). Not only did Time make the perennial mistake of linking global warming to a single land-falling storm; it didn’t even choose one of the strongest ones.

Meteorologically, Severe Tropical Cyclone Glenda told a more frightening tale. It was a rapid intensifier like Wilma. The storm formed off Australia’s northwestern coast on March 27, and within a day had swelled into a Category 4 storm, en route to Category 5. Moving to the southwest along the coast, Glenda weakened to a Category 3 storm before making landfall in the Pilbara region of western Australia near the town of Onslow. This de-intensification prevented more severe damage at landfall, but at Glenda’s peak, one estimate based upon satellite imagery put the storm’s central pressure at 898 millibars (though the Australian Bureau of Meteorology put it at 910 mb).

Still more powerful was Severe Tropical Cyclone Monica, which churned from April 17 to April 24, 2006, very late in the season by Southern Hemisphere standards. Originating in the Coral Sea, Monica was a small storm, not unlike Cyclone Tracy of 1974; at one point it even seemed similarly aimed at the city of Darwin. And Monica could have been even more devastating. Despite its late-season formation, it was one of the two strongest tropical cyclones ever recorded in the Southern Hemisphere, with maximum sustained winds approaching 180 miles per hour—what might be considered Category 6 strength if we assume that Category 5 runs only from 155 to 175 miles per hour or so (a similar span to the categories below it).

Monica’s minimum central pressure reading is disputed. Just before its landfall in the Northern Territory, as the storm left the Gulf of Carpentaria and moved into the Arafura Sea, satellite-based estimates put its intensity at a stunning 879 millibars. For the Southern Hemisphere, such a measurement would tie the satellite estimate for 2002’s Cyclone Zoe (which also had maximum sustained winds of 180 miles per hour at its peak). In fact, using an automated method called the Advanced Dvorak Technique, scientists at the University of Wisconsin at one point estimated Monica’s minimum pressure to be as low as 868.5 millibars—which, if accurate, would be the lowest pressure ever measured anywhere on Earth at sea level.

The 868.5-millibar estimate doesn’t count as an official record, however, and isn’t necessarily reliable. Australia doesn’t send reconnaissance flights into tropical cyclones as the United States does, and intensity estimates from satellite images have many problems. The Australian Bureau of Meteorology apparently judged Monica’s lowest pressure to have been considerably higher—905 millibars, a huge discrepancy. The storm’s true intensity will always remain a mystery, a fact that lends strength to Landsea’s arguments about the immense difficulty in tracking down reliable and consistent intensity figures for storms across the globe. If we can’t get dependable measurements for Monica in 2006, how could we have done it for storms in the 1970s?

 

 

Severe Tropical Cyclone Monica just north of Australia on April 23, 2006, possibly the most intense storm ever observed in the Southern Hemisphere.
Image credit: Naval Research Lab

 

April 24 was the day Monica made landfall in Australia’s Northern Territory, west of the Aboriginal township of Maningrida (sparing Darwin another blow). It also happened to be the day William Gray was slated to appear before a crowd of scientists at the Hurricanes and Tropical Meteorology conference in Monterey, California. As per the e-mail dialogue several months earlier, Gray had been removed from the panel debate scheduled to occur the next evening, but he had submitted a paper to present instead. The online write-up suggested it would be a full-on attack on the theory of human-induced global warming.

Earlier in the day, meteorologist David Nolan of the Rosentiel School of Marine and Atmospheric Science at the University of Miami, who sometimes collaborated with Emanuel, had presented perhaps the scariest idea yet about the relationship between hurricanes and the climate system. Using a computer model, Nolan and Emanuel explored the possibility of “spontaneous” genesis of tropical cyclones in a warmer world (perhaps one that had been sufficiently heated thanks to an enhanced greenhouse effect). The scientists accepted the view, dating at least back to the work of Riehl, that hurricane development must be sparked by an independent disturbance. But they suggested that this constraint, while important in our present climate, might not always exist in the future, and might not have existed in previous warmer eras of Earths history. In a hot enough world, seas conducive to hurricanes might stretch much farther pole-ward, into regions where the Coriolis force deflects winds more strongly than it does nearer to the equator (the effect of the Earths rotation increases towards the poles). This might allow hurricanes to come together from “random convection” and thus—it went without saying—occur far more frequently and in locations where we are unaccustomed to seeing them in the current climate.

Nolan didn’t have the misfortune of having to compete head-on with Gray’s speech later that afternoon. Former NOAA Hurricane Research Division director Hugh Willoughby, however, wasn’t so lucky. As Willoughby ruefully recalls, “I sure knew who the people who were interested in my work were. All six or seven of them.” It certainly seemed as if a large proportion of the more than 550 scientists on hand for the conference—many more than would have attended the same event in the decades before hurricane research became sexy—had piled in to hear the grand old man of tropical meteorology.

For the assembled scientists—who, just like crowds of hurricane preparedness experts, liked a little entertainment now and again—Gray didn’t disappoint. He started with a slide in black and red type, set against a light green background:

 

SOCIETY’S PROGRESS CAN CONTINUE ONLY AS LONG AS ITS OLD MEN PERSIST IN DECRYING THAT “EVERYTHING IS GOING TO HELL”

 

This quotation Gray attributed to an “unknown philosopher.” Then he launched into a favorite routine—recalling yesteryear.

“As I look out over the crowd, I think I’m the oldest guy here,” he began. “Where were you all in 1961, June, in Miami?” That was the month, Gray recounted, that he had attended the second-ever incarnation of this now-biennial Hurricanes and Tropical Meteorology conference. He had missed the first conference in the fall of 1958, he added, because “I couldn’t get Herbert Riehl to agree to pay my travel down.”

“All you young people are reinventing the wheel, you know, in ’61 we had it all worked out,” Gray continued, to much laughter. “And then the damn computer and satellites came along and ruined everything. And that’s where we are today.” He turned back to his slide. “When I give you hell . . . it is raz/hell,” he warned. “And that’s what I intend on doing.”

And so it went, on into Gray’s dismissal of concerns about human-caused global warming and the global climate models upon which they are based. He had toned down his presentation to this highly trained—and critical—audience not a whit; if anything, he had amped up the humor. He had even added a new schtick to his standard “Ice Age” joke recapping alarmist quotations about “global cooling” from the 1970s: a PowerPoint presentation of a succession of Time magazine covers. First, a faux cover purporting to be from 1945 clarioned the possibility of global warming. The second, an actual cover from 1977, announced “The Big Freeze” with a photo of a man wearing a ski mask with snow encrusted on it. The third was the aforementioned “Be Worried. Be Very Worried” cover from that very month, showing a polar bear on a dwindling ice floe.

But Gray wasn’t finished roasting Time. In a final slide, he presented a cartoon of a person standing in what looks like an ice cube, thinking “It’s Cold! Burrr!,” with the familiar Time magazine logo above. “I’ve projected this,” Gray said. The date: 2036.

As the talk continued, so did the patter. Gray—the “Howard Stern of meteorology,” as one scientist described him to me—slammed entire communities of researchers with lines like “Anybody, any experienced meteorologist that believes in a climate model of any type should have their head examined, they really should.” He accused climate scientists of being “Prisoners of the Clausius-Clayperon equation,” the well-known law of physics. Finally, he gave his audience a quotation from Michael Crichton:

 

Historically, the claim of consensus has been the first (not last) refuge of scoundrels; it is a way to avoid debate by claiming that the matter is already settled. Whenever you hear the consensus of scientists agrees on something or other, reach for your wallet, because you’re being had.

 

And there Gray nearly ended, to laughter and great applause from the audience. Basking in the response—feeding off it, just as a hurricane feeds off the ocean—Gray couldn’t resist one more comment. “I’m sorry I’m so reluctant to express my views on things,” he said.

As this was a professional scientific meeting and not the National Hurricane Conference, there was a second act: questions from the audience. The first came from Peter Webster, whom Gray had embraced and urged to get to work on hurricanes at the same event two years before.

In a very civil tone, Webster—the type of scientist who always seems to ask the first question after a lecture—challenged Gray’s account of the role of the thermohaline circulation in driving the recent Atlantic warming. In particular, Webster referenced a recent study in the journal Nature that had detected an apparent slowdown of this circulation. He didn’t get to phrase a fully formed question before Gray cut in.

Oceanographers cannot directly measure whether the thermohaline circulation is speeding up or slowing, Gray countered, and then his voice began to rise. “We’ve been working fifteen or twenty years on this,” said Gray, “and you come in, right the last year, and throw all this out the window! Do you really know what you’re talking about, Peter?”

“Bill, I think I do,” continued Webster calmly. In Gray’s presentation, he said, “the thermohaline circulation looks nothing like anybody’s ever seen. So, I think I know what I’m talking about.”

“You know what you’re talking about most of the time, Peter, I have great admiration for this,” said Gray. “But on this you don’t know what you’re talking about.”

“I think that will have to be settled outside,” said the moderator.

The next questioner was Holland, Gray’s former student and Webster’s friend. The tag-team approach sparked uncomfortable laughter from the audience.

“I always love Greg Holland’s questions,” Gray said gamely. “They’re wonderful.”

“This was highly entertaining,” Holland began. “But unfortunately you obfuscate the real issues at hand.” Holland then launched into an impassioned defense of climate models and the integrity of the researchers working with them—who included many of his own colleagues at the National Center for Atmospheric Research (NCAR) in Boulder. For Gray to denounce so many hard-working researchers in such an absolute fashion, Holland argued, “does the science a disservice.” The statement drew Holland his own round of applause.

But Gray had the microphone and the stage, and he had the last word.

“Oh Greg,” Gray responded, “I didn’t know you as a highly religious person. That’s a belief. That’s a belief, not a reality.” It was one of the worst slights one scientist can bestow upon another—the accusation that one’s conclusions have been determined by a preconceived opinion, a theology. It echoed Redfield’s attacks on Espy more than a century earlier.

“They’re trying hard, they’re good scientists—some of my best friends are modelers. But it can’t be done,” Gray went on. “No, Greg,” he finished. “Since you’ve joined NCAR, you’ve come to religion.”

The next speaker was Emanuel.

“Those of you who are here because you think you’re going to hear a rebuttal will be disappointed,” he said, quelling another ripple from the audience. Then he launched into an equation-intensive talk that sought to reconcile his theoretical understanding of hurricane intensification with the latest observations. A decline of trade-wind speeds over the main development region, Emanuel suggested, seemed to have amplified the sensitivity of Atlantic hurricanes to global warming. So had a poorly understood but apparent cooling of the tropical tropopause, which had decreased the temperature in hurricanes’ outflow regions even as temperatures at the sea-surface heat reservoir had increased (thus upping the potential intensity achievable by storms in two separate, complementary ways).

Emanuel’s presentation limited itself almost entirely to purely scientific content. It was highly theoretical, geared toward the scientifically advanced audience. Emanuel did, however, make one side remark about the “previous speaker”—who he never mentioned by name, but who he described as being “in denial” about global warming.

 

The next evening’s debate, featuring Emanuel, Webster, Landsea, and Johnny Chan, went off without a hitch. The moderator, Russell Elsberry of the Naval Postgraduate School, cautioned at the outset that there were to be “no personal comments as to character or any other thing.” “Everyone involved in this panel discussion is searching for the truth, and I want to compliment everyone for doing that,” offered Landsea, once again playing the role of conciliator, and once more using humor to that end. “I get along personally with everyone involved and I want to continue that—even if they’re wrong,” he continued.

Emanuel, too, had a gloss on the state of affairs. “I think the people you see up here in front of you have conducted this debate in a very civilized way, I hope we can say we’re the models,” he said at one point during the discussion. “It’s not us who have been the problem. It’s certain members of the press and certain people you don’t see up here.” In slamming the press, the scientists mostly seemed to have in mind the Wall Street Journal story that had depicted such a nasty conflict between Gray and Curry. “They like to try and make it look like everybody’s fighting everybody,” said Webster, who seemed particularly incensed at journalists. (Earlier at the conference, spotting me walking and talking with Richard Kerr, a reporter for Science, Webster had joked, “Oh my God, now there’s two of them.”)

Gray was in the audience for the debate. Even if he’d wanted to speak, though, he wouldn’t have been allowed to. The organizers, not taking any chances, had stipulated that questions from the audience would be submitted in writing and read aloud by the moderator.

And so there followed a lengthy, substantive discussion. One memorable moment came when Landsea publicly apologized for the behavior of NOAA, his employer. Insofar as the agency had claimed a “consensus” on hurricanes and global warming on its Web site, Landsea said, “that was a mistake to do.” He continued: “I think that was a misguided attempt by the public affairs folks to try to provide a broad-brush answer to a pretty complex problem.”

Johnny Chan, meanwhile, limited his case to the storms of the Northwest Pacific, where, inspired by Gray, he had introduced a statistical forecasting system for seasonal typhoon activity. In the context of the debate over hurricanes and global warming, this basin had huge significance because it hosts such a large number of storms (and so many very intense ones). Sea-surface temperatures in the Northwest Pacific, Chan argued, are “so high that a little bit of change is not going to do anything.” In much of the basin, he noted, these temperatures exceed 28 degrees Celsius for most of the year, well above the general 26- to 27-degree threshold for storm formation in the current climate. Chan argued that, at least for the Northwest Pacific, storm intensity seemed more strongly controlled by factors like wind shear: “Thermodynamics cannot really explain the variations.”

What emerged most strongly from these exchanges was that until someone carefully reanalyzed the global storm intensity data and provided a record that both sides could accept, they would remain at an impasse. Fortunately, it now came up that an outside scientist, Jim Kossin of the Cooperative Institute for Meteorological Satellite Studies at the University of Wisconsin-Madison—who’d flown with Landsea on the record-setting Gilbert flight back in 1988 and was in the audience listening to the debate—had volunteered to undertake a comprehensive satellite-data reanalysis. “Jim, get back to work,” Landsea joked at one point.

The next morning at the conference, I sought out Gray to hear his impressions of the debate. True to form, he said he thought Chan and Landsea had done a “great job.” He also said once again that Emanuel could sell ice cubes to the Eskimos and steam heat to the Amazonians. Then I got my turn as target practice when Gray jokingly asked if he could call me a “hired gun of the left.” I replied that I wouldn’t sue him. Then he said, “Well, maybe I can call you a hired gun of the middle.” It felt strangely pleasant to be the subject, however briefly, of one of Gray’s jibes.

I asked Gray if he felt bad that he hadn’t been included in the debate. My notes say: “he said, no, he was just proud of his students, but also that they kicked him off the panel—but he was proud of his students.”

 

A few weeks later, at the twentieth annual Florida Governor’s Hurricane Conference, held in Fort Lauderdale, Gray was again in his element. He’d been the final speaker of this massive event (with 3,800 attendees this year) since 1994. Now, his long arms planted on either side of the podium, he was passing the torch to Klotzbach.

Having listened to a string of the previous speakers—including Florida’s Secretary of Community Affairs, Thaddeus Cohen, who could not seem to complete a sentence without including the phrase “in terms of”—I had a better understanding of why any sane audience would respond enthusiastically to an irascible old guy with a humorous slide show. And I could better appreciate that such crowd-pleasing was one of the skills Landsea had taken care to pick up from his teacher. I’d missed Landsea’s workshop the previous day on “hurricane myths,” though at the National Hurricane Conference I’d seen him give a similar talk. Alongside the concept that global warming might strongly influence hurricanes, he had tossed in hilariously dumb ideas, such as the notion that we might defeat hurricanes by arming our coasts with giant fans to blow them back out to sea, or towing Arctic icebergs into their paths, or even hitting the storms with nuclear bombs. (This last conceit, Landsea noted, would simply create a “radioactive hurricane.”)

Having heard Gray’s routine multiple times by now, I listened for elements that might be different. But I quickly saw that every Gray talk is new. It all tumbles out a bit differently each time, sometimes more strident, sometimes less. Today seemed a relatively mild day. Although Gray gave his standard anti-global warming talk with its three pillars—the weaknesses of numerical modeling, the erroneous water-vapor feedback loop, natural cycles driven by the thermohaline circulation—he also tailored his words specifically to Florida, the most hurricane-exposed state in the nation. Gray’s central message was simple: Floridians had been lucky for a long, long time. From 1966 until 2003, the peninsula had seen only one major hurricane landfall, that of Andrew in 1992. “What was happening those thirty-eight years?” Gray asked. “You were all moving down here, having children; they were growing up, expanding their houses.”

Gray’s contention that Florida’s vulnerabilities sprang from societal factors like population growth and increased development of valuable coastal property repeated a mantra of the hurricane community whose validity is tough to dispute. But then he told Floridians to drop global warming from their litany of concerns as they contemplated their future: “Worry about nature. Nature’s tough enough. It’s going to do a lot of harm to Florida, and that’s your main threat I think.”

What Gray modulated in tone, however, he made up for in length. After forty minutes, he was just beginning a dive into paleoclimatology. He kept right on going; as he had jokingly told the crowd earlier, “I have a little more views I want to get off my chest.” And then once again, Gray finished to a standing ovation (albeit from a somewhat thinned-out audience).

The reception reminded me of an encounter before the talk, when I’d been sitting and chatting with Gray about the history of hurricane science. Two men came up to us, with a boy who looked about ten years old. One of the men obviously knew Gray, and he asked if Gray would pose for a picture with the boy, presumably his son.

The boy, the man explained, wanted to be a weatherman when he grew up.