1,444 Candlesticks: The dark origins of modern fire science

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Margo Schulz recalls a time from her childhood when large black snowflakes drifted down from the sky. She remembers those warm summer days, outside with her sister hanging laundry to dry. They made a game of reaching up and catching the blackened flakes mid-air. They were burnt pieces of paper: half a birth certificate, part of a love letter, half a Deutsch Mark note – the detritus of 50,000 lives incinerated just a few miles away.

The year was 1943. Schultz lived in the town of Bergedorf, several miles southeast of Hamburg, Germany. On the night of July 27-28, a British air raid had dealt Hamburg a devastating blow: 739 planes dropped more than 3 million incendiary charges – sticks of phosphorus or magnesium that hissed like Roman candles as they fell onto rooftops. What made the raid distinctive was the way it was orchestrated. Through a technique called “area bombing,” all of this firepower was focused on a small section of the city, its eastern quadrant, where middle- and working-class families lived in densely-packed six-story apartment blocks.

Within 20 minutes, thousands of blazes merged into a single firestorm. The fires greedily sucked in fresh oxygen, drawing in hurricane-strength winds, which splintered trees and launched burning planks of wood into the air. The hot gases and smoke rising from these flames pushed an angry, anvil-shaped thunderhead 30,000 feet into the sky. The black snowflakes that Schultz playfully plucked from the air for several days afterward were the exhaled breath of that firestorm: bits of paper lifted thousands of feet by the fire’s hot, buoyant updraft, which drifted back to earth as the air cooled.

Schulz’s story is one of many collected by the British historian Martin Middlebrook in his book, Firestorm Hamburg: The Facts Surrounding the Destruction of a German City 1943. Her story hints at how different observers can draw vastly different meanings from a singular event.

The novelist Hans Erich Nossack contemplated how the bombing had laid bare the role that random chance plays in every person’s life, in his account, The End: Hamburg 1943. On the night of the raid he happened to be 10 miles outside Hamburg – his first time out of the city in many years. Contemplating his unlikely role of spectator, he says: “I don’t know why.”

Nossack’s own home was destroyed, but he was surprised to find the home of a friend completely intact; it was the only building still standing on its block. His friend showed him where 37 bodies lay in the garden – pulled from a bombproof shelter next door. Those souls might easily have survived, had a coal bin not caught fire next to the shelter and cooked them inside it. Nearby, Nossack and his friend found a public garden where a poplar tree still lived. Parakeets, somehow escaped from broken cages inside burning houses, now perched in its singed branches. Within days, the tree would sprout new leaves.

As Allied forces advanced across Germany in 1945, the fate of Hamburg would take on other sorts of meaning. Eleven hundred members of the U.S. Strategic Bombing Survey (USSBS) fanned out just behind the advancing troops, seeking out civic and government records, to study and reconstruct the effects of bombing raids conducted over the previous two years. Those records were sometimes found in city offices where they belonged – other times, hidden in private homes, in barns, in caves, in hen houses – even in coffins.

On November 2, 1945 the USSBS published a report, “A Detailed Study of the Effects of Area Bombing on Hamburg,” which assessed the city’s fate in strikingly antiseptic terms. Immediately after the July 1943 raid, the city’s population had plummeted from 1.5 million to 845,000. Daily ridership on the city’s tramways fell by 70 percent. The number of local firms selling clothing, food, and furniture plummeted, while those selling coal, jewelry, radios, and machinery largely remained. Perhaps most important: the firestorm and two other major air raids on Hamburg’s residential areas cost the city 1.8 months of industrial economic output. Compared to precision raids against factories and infrastructure, these “area bombing” raids against workers were found to be only about 30 percent as efficient at reducing industrial production.

Of all the different ways of seeing Hamburg’s destruction, that of Hans Brunswig, the city’s fire chief, turns out to have been surprisingly telling. A few nights after the firestorm, he conducted a small but poignant experiment. He and his workers mounted 1,444 small candles onto a wood board – representing the densely packed buildings of Hamburg. They then carefully lit a ring of 64 candles near the center of that grid. Within seconds, those inch-high flames leaned inward – pulled together by their collective in-drafts of fresh, oxygen-rich air. The 400 candles inside that burning perimeter quickly ignited, and together, their inward-leaning flames merged into a single, tightly-wound column that shot four and a half feet into the air.

Brunswig’s experiment was one of the first studies of what is now called “extreme fire behavior.” And the Hamburg firestorm, and a series of military experiments that followed it during the Cold War, still provide much of the foundational knowledge that fire scientists rely on for their research today. Many of the dangerous behaviors that are now seen in modern wildland fires were described in Hamburg and other firestorms during World War II: flaming tornadoes called fire whirls; or jets of flame that can surge 100 feet ahead of a burning front.

As it turns out, some of today’s scientists are zeroing in on something that Brunswig also realized. Brunswig fought urban fires, not forest fires, but he saw the importance of the fire’s plume – its rising column of hot, buoyant smoke – for driving extreme behaviors. To find out more about their fascinating work, check out my cover story, published in the April 3 issue of High Country News.

Photo courtesy of Flickr user Daveblog.

 

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