Perhaps, but the industry itself was instrumental is setting up the volcano monitoring system it is currently railing against. After several high-profile ash-plane encounters in the 1980s—including a British Airways flight’s loss of all four engines over Indonesia in 1982, and the Alaska incident in 1989—an international conference of industry scientists, along with meteorologists, aircraft engineers and volcanologists like Hickson, agreed in 1991 to create a worldwide network of “volcanic-ash advisory centres” responsible for alerting airlines and national aviation authorities when ash clouds appear.
These nine offices—run by national weather services under the auspices of the UN’s International Civil Aviation Organization (ICAO)—use satellite-based infrared scanners to produce maps showing the shape and movement of a cloud, once seismic monitoring tells them an eruption is taking place. The images are colour-coded to show the varying density of the haze, but until last week the concentrations didn’t much matter. “There is no quantification of ash content in our advisories,” explains Richard Hogue, the Environment Canada official who oversees Canada’s ash advisory centre in Montreal. “Even a small quantity can cause millions of dollars of damage to a jet engine. So the ICAO had told us, ‘Look, you just tell us where the ash cloud will be so aircraft can steer clear.’ ”
Certainly engine and aircraft makers see little margin for error. General Electric, which makes engines for both Boeing and Airbus planes, posted interviews on its website this week in which its engineers warn that volcanic ash should be “avoided altogether.” Even small amounts of the dust can melt into a glass-like substance that gathers on the turbine blades, collecting in tiny air holes that allow cooling in the engine, says Leslie McVey, a safety engineer with the firm. “It can cause the engine to stall, and possibly to flame out.”
Pilots were similarly skeptical, as there is no on-board system to date that would allow them to detect the presence of volcanic ash, much less its concentration. In many cases, a flight crew’s first indication of ash is an acrid smell that fills the cabin and cockpit as warm air is pumped in off the engines. Pilots may also hear the scratch of silica-heavy ash hitting their windscreens, by which time it could well be too late: engine components would already be overheating.
Small wonder, then, that the head of the European Cockpit Association (ECA), representing 40,000 pilots, was less bullish than the airlines on the idea that Europe might have so-called “safe flying corridors” within the ash-affected zone. “I don’t think there is a definitive answer to whether it is safe or not,” president Martin Chalk told the Guardian newspaper. “ECA is concerned that such far-reaching decisions would be taken under such enormous human, political and commercial pressures.”
Still, for all the bother, disruption and economic loss, the flight crisis could have been much worse. So far, the Iceland eruption has been relatively minor, producing just 2,700 tonnes of sulphur dioxide a day. (In comparison, when the Philippines’ Mount Pinatubo exploded in 1991, it sent aloft 18 million tonnes of SO2, enough to reduce the amount of sunlight the earth received, cool the globe by 0.6° C for more than a year, and alter weather patterns.) Eyjafjallajökull is on the world’s radar—literally—only because it is covered by a glacier. The molten magma forcing its way up through the ice is producing vast amounts of steam, which has carried the ash far higher and further than an eruption of similar magnitude would in warmer climes.
The real surprise, say those who study volcanoes, is that this type of thing doesn’t happen more often. The Pacific “Ring of Fire” is dotted with dozens of ice-covered volcanoes from northern Japan to Alaska and all the way down to Patagonia. In Iceland alone, there are 33 different volcanoes that have blown since the end of the last ice age 12,000 years ago—a blink of an eye in geological terms. And all of them have the potential to be just as, if not more, troublesome to air travellers. “We’re talking about disruptions on a potentially global scale,” says Hugh Tuffen of the U.K.’s Lancaster University, a volcanologist who has done field work in Iceland for the past 12 years. What insights has he gleaned? “What we’ve learned is that you can’t really predict what Icelandic volcanoes will do. This could all end in a matter of days, or it could go on for years.” Tuffen’s fieldwork has mostly concentrated on the much larger, and more active Krafla volcano, 25 km away, but he’s already making plans to turn his attention to Eyjafjallajökull this summer. “I’ve always looked at it and thought, ‘That’s a nice one. I hope it blows up sometime,’ ” he says. Even an ash cloud has a silver lining.
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