He races back up to the house, checks the tank, hears the reassuring sound of water splashing into it. Makes a last-minute inspection of his family’s defences. He lays out hoses and nozzles, looks over the fittings and connections. Everything seems in order.
BALANCING ACT
As Wood heads down the drive, he pauses. Listens. He’s struck by the eerie silence of the morning. The glare is blinding, the air a shimmering haze. The land is seared and withering under the sun’s relentless heat. There’s a strange smell in the bush, vaguely reminiscent of cloudy ammonia. A flock of choughs are huddled together, so exhausted by the heat they can’t be bothered stirring. A pair of wrens—beautiful blue feathers, vicious eyes—dart about, little swoops.
He watches a leaf twist and spin in the morning light. Then another. He follows their zig-zagging flight, sees more join them. Falling leaves: there’s been an astonishing number of them lately.
He gets out of the car, crouches down, runs a hand through the litter on the ground. Picks up a handful and lets it fall. Leaves, bark, twigs, crumbled branchwood drift away. The leaf litter is a world unto itself. Wattle seeds, gumnuts, parched bones. A dragonfly’s glassy wing. Creatures too small to be seen with the naked eye. Dry leaf mould. Layer upon layer of it, fifteen or twenty centimetres thick in places. All of it crumbling into the great cycle of death, decomposition and birth that is the forest floor. It’s thicker than he’s ever known it to be. And the rock-hard earth below it hums with stored heat.
The litter is a frightening sight for anybody who’s observed with a knowing eye its steady, remorseless accumulation over recent years. It’s more than just debris: at this time of the year it’s an accelerant. Might as well be petrol.
As he watches those parched fragments trickle through his outstretched fingers, Wood thinks about the interwoven influences of nature and humanity that have brought the bush to such a state. That simple handful of litter bears testament to years of drought, devastating climate change, an environment, already the most flammable in the world, tormented and stretched to breaking point.
All those falling leaves—what do they mean? The trees are in trouble, they’re like a ship on a reef, jettisoning cargo, struggling to survive.
The rainfall in the past year has been the lowest on record: in January 2009 only 0.6 mm of rain fell, the driest start to a year Victoria has ever recorded. The water storage is lower than it’s ever been: Melbourne’s dams started the year at a fearful 34.7 percent capacity and by now they must be at rock bottom. Groundwater levels, soil moisture, fallen logs and stumps are all severely affected. They’re all connected, all indicators of danger: the lower the moisture level in the soil, the more ready the bush is to burn.
The drought reached its nadir in the three brutal days of over 43 degrees a week ago. Eleven consecutive days of 30-plus, conditions not seen in 160 years of white settlement. Temperatures like that cure the land, dry it out, prime it.
And today?
Jesus wept. The worst of all. Scorching heat, negligible humidity: less than 10 percent predicted. The humidity is important. The lower the moisture in the atmosphere, the closer things are to ignition. The wind already feels like a gale blown up from the bowels of hell. And it will get worse as the day wears on.
The McArthur Forest Fire Danger Index is the scale used to measure the threat of fire in the Australian bush. Developed in the 1960s by legendary fire scientist Alan McArthur, it weaves together variables such as wind, fuel, drought, humidity and temperature to come up with a numerical rating that can be applied to any locality. It uses Black Friday—January 13, 1939—as a measuring stick: the index on that terrible day, when seventy-one lives were lost, was set at 100, which scientists believed to be as bad as it could get. A day of Total Fire Ban, when it is a serious offence to light a fire anywhere in the open, is declared if the index reaches 50.
Today the fire danger index is off the scale. It varies according to local conditions, but in the countryside around Roger Wood’s home it’s in the 180s. The weather has gone mad, and the bush is ready to explode.
Climate has been the driving force behind much of human history. It drove our ancestors in and out of the caves, it propelled the Mongols into Europe, the Vandals into Rome. Its vicissitudes were the reason that empires from the Sumerian to the Egyptian—arguably even the Napoleonic, the Nazi—rose and fell. It allowed humankind to colonise the New World, twice.
Until very recently, humans were outdoor animals with an awareness of weather in our bones. But although we’ve lived forever in its icy blasts and scorching heat, our understanding of it is still surprisingly limited. We can send a remote-controlled vehicle to Mars, but our best scientists cannot accurately predict the timing of a change in a local wind that will turn a fire about and kill scores of their fellow citizens.
Why? Because the weather is so damned complicated. Even with their staggering computational capabilities, their satellites and multidimensional radar imagery, the experts are giving us, at best, an educated guess. Think for a moment about the phenomenal power needed to shift air masses the size of continents around the globe, or lift enough moisture to deposit millions of tonnes of rain onto the Earth’s surface every day.
And the atmosphere—thin blue film of gas it might appear to be from outer space—has a complexity to match that power. Every parcel of air, from a zephyr to a hurricane, is constantly subjected to a battery of influences that include pressure forces, friction, buoyancy, and the deflection of its motion caused by the Earth’s rotation, known as the Coriolis effect.
Weather is driven by nature’s need for equilibrium. When air ascends in one place it has to come down somewhere else. Simple. But the ramifications interconnect in bewildering ways that have only become apparent with the rise of modern communications: a drought in eastern Australia, for example, could be counterpointed by heavy rains in the southern states of the USA. Low-pressure storms in Darwin will coincide with both a high-pressure system in Tahiti that causes dry weather and heavy rain in Central Africa and the Amazon. They are all connected.
The driver for this eternal flux, the source of all this power, is the sun. The sun’s atmosphere is so hot, at some 6000 degrees Celsius, that atoms there can’t hold onto their electrons. At its core, the sun, powered by a cascade of hydrogen fusion reactions, maintains an unimaginable temperature of around 14 million degrees. This gargantuan nuclear powerhouse delivers some 175 trillion kilowatt hours of energy to Earth every hour, generating in a day as much power as 200 million atomic bombs.
If the planet was as flat as our ancestors believed it to be, the upshot of that would be relatively straightforward and weather much more predictable. But because of Earth’s shape, rotation and tilt, the radiation that streams into the atmosphere is distributed unevenly. It is strongest at the equator, which is why that is the planet’s torrid zone, but the equator cannot just keep on becoming more torrid. The equilibrium imperative ensures that the energy that comes in at the equator moves towards the poles. The circulation of the atmosphere and of the ocean currents is the means by which this happens.
This constant energy transfer causes both air density and temperature to vary enormously, to be in a continual state of flux, as weather phenomena large and small—from super-cells to raindrops—struggle to achieve a balance. The instinct for equilibrium is responsible for the wrenching convolutions and sheer variety of our planet’s climate: for the Roaring Forties and the Doldrums, the crushing droughts and the sheets of lightning and ice.
Ultimately, it is also responsible for the teeming variety of life on Earth: for the sleek-backed birds that slip among the manna gums, the nodding greenhood and spider orchids, the fern-filled gullies of the kind that weave their way through the Kinglake Ranges. They are manifestations, all, of climate. And so are the fires that arise time after time and render those varied colours down to a uniform coal black.
INCIDENT CONTROL
It is around midday and Roger Wood is heading
for the gate when somebody flags him down.
‘Morning, Roger!’ Steve Andrews, his neighbour, standing at the intersection of the two properties.
‘Morning, mate.’ He wipes some of the sweat off his neck. ‘Hot enough for ya?’
‘Too bloody hot. What do you know about that, Rodge?’
What? He follows Steve’s outstretched hand. A column of smoke has appeared in the north-western sky behind him. He raises an eyebrow: that was quick. It wasn’t there when he drove down a few minutes ago. Looks a long way off, though.
He listens in to the police radio, learns that a fire has just broken out at Kilmore East. Does a quick mental calculation.
‘Should be right, Steve. Good—what?—fifty k’s away? Change oughter be here before it gets anywhere near us.’ He leaves his neighbour standing there, but as he cruises up the mountain he feels a ripple of anxiety moving in his chest.
Some time just before 11.50 am, a fire has been started by a fallen power line on the Pentadeen Spur at Kilmore East. As it races towards the Hume Highway an Incident Control Centre is established at Kilmore. The controllers are briefly hopeful that the highway, a four-lane expanse of bitumen and gravel, will act as a firebreak. But the fire barely pauses as it leap-frogs the Hume along a five-kilometre front and hits the messmate forest on the eastern side. Somewhere in there it begins crowning, roaring through the upper canopy, leaping from tree to tree. It multiplies its intensity by a magnitude of five, then ten. The pyrocumulus cloud above swirls some eight kilometres into the atmosphere. The fire storms through the countryside at a rate two to three times faster than predicted by the McArthur Forest Fire Danger Index.
Fire scientist Nic Gellie has commented subsequently that this astonishing speed and ferocity is changing the way some scientists think about fires, forcing them to question the orthodox concept of fire spreading in uniform ellipses. ‘Under the conditions of Black Saturday,’ he says, ‘spotting, fires merging, and convection columns ruled the fire processes on the day.’
A motorist is travelling towards Whittlesea when he sees the fire coming at him. He turns around, puts the foot down. The fire begins to gain on him. He accelerates even harder; still the fire gains. He swears later he was doing 140 kilometres per hour when it overtook him.
The wind drives the flames up onto the launch-pad ridges. It shatters and snaps the tall trees, whirls the burning fragments into the valleys below or across to adjoining ridges. The experts call this spotting, but that’s a feeble term to describe what it looks like to those in its path; maybe ‘saturation incendiary bombing’ would be more accurate.
Massive winds whip branches and strips of bark from burning trees and whirl them so high they run into winds blowing in other directions. They are chaos in flames, can land anywhere, inflict incredible amounts of damage; particularly dangerous are the long, thin strips of ribbon bark. They burn for a long time and cover enormous distances. The fires that will wipe out farms and wineries along the Yarra Valley are started by debris torn from mountain tops many kilometres away. Fire scientist Kevin Tolhurst estimates that on this day there are embers travelling a record thirty-five kilometres.
One CFA volunteer says later: ‘I felt like I was in the middle of a Ridley Scott movie: we were in a gully watching a shower of burning embers arc overhead, catapulting from one summit to another.’
The initial progress of the Kilmore East fire
And those ‘embers’ can be huge. Later that day a policeman is driving up The Windies with no fire in sight when what he describes as ‘a firebomb the size of a caravan’ comes whirling out of the sky and lands beside him. He’s still blinking in shock as the missile ignites the surrounding bush, starting an instantaneous conflagration that goes racing away.
This process is repeated a thousand, a million times over as the fire careers down from Kilmore East. The front is like a spiral nebula, whirling through space and spraying great arcs of energy in every direction.
RED WIND
Bruce and Margaret Newport, in Chads Creek Road, Strathewen, feel relatively confident of their ability to defend their home. They are well equipped with pumps and tanks, and live a considerable distance from the bush on an Angus beef farm they’ve kept wet and green in preparation for a forthcoming field day. They are experienced country folk. When the fire approaches late that afternoon, Margaret and the children shelter inside while Bruce patrols the boundaries.
Then he watches in horror as the wind tears the roof from the building. ‘The whole thing peeled back like a tupperware lid and came off,’ recalls Bruce. ‘Beams and all.’
The family survive, but only just.
When many survivors look back on Black Saturday, it is the wind that looms largest in their memory. That hot red blast was the engine that powered the juggernaut.
‘It was blowing a bloody gale up on the mountain,’ says Roger Wood. ‘Never seen anything like it. I was driving a two-tonne Pajero, and when I was out in the open it was rocking like a sailboat in a storm.’
To be in an exposed location in the bush that day was to feel that you were in the grip of a protean force: every branch, each leaf and twig was alive and writhing, straining, breaking loose, whipping away. The grasses bowed and rose as if invisible giants were running through them. One firefighter described a large limb caught up in the power lines, how it made him think of the skeleton of a galleon. As he watched it was torn apart, shattered into fragments that speared fifty metres through the air.
In the Kinglake Ranges it was probably worse than most places because of what fire authorities call the Ramp, where the flatlands rise into the foothills and the slope intensifies wind conditions. The result, local fire managers report, is that winds in the ranges are often twice as strong as statewide forecasts.
A big running bushfire is an extraordinarily complex concatenation of events, a synchronicity of fuel, topography, heat, drought and human activity. But it is the wind that causes that frayed conductor on the Pentadeen Spur to snap and come crashing to the ground, sending an electrical charge arcing into the grass.
It is the wind that picks up those first thin fingers of flame and transforms them into something extraordinary, propels them in long, expanding ellipses out into the grasslands, then into the pine and bluegum plantations to the south-east.
Bureau of Meteorology data suggests that the recorded wind reached speeds of up to 120 kilometres per hour. But a raging bush-fire will generate its own tornadic winds, and they can be much more powerful.
Nic Gellie, who modelled the reconstruction of the Kilmore East fire for the Department of Sustainability and Environment, estimated that the wind around the fire was of cyclonic force, hitting speeds of between 150 and 200 kilometres per hour. (There were no weather stations located at the fire front, so these are estimates based upon the damage done at places such as St Andrews and Strathewen, where roofs were torn from houses and massive trees corkscrewed out of the ground.)
But what is wind? And why did it go berserk on Black Saturday?
Around the world, its names are legion and rich with local memory and lore: brickdusters and mistrals, cat’s paws, diabolos, doctors, the Steppenwind. There is the bitter Pittarak that whistles off Greenland’s fields of ice. The suicide-inducing foehns. The fire-driving Santa Anas. The Harmattan, the ‘hot breath of the desert’, the name given by Tuareg nomads to the sirocco and said to derive from the Arabic for ‘an evil thing’.
Humans have struggled to make sense of wind since the dawn of consciousness. The ancient Indians saw it as the breath of life. To the Greeks Aeolus, the Keeper of the Winds, lived on a floating island, and is remembered for giving Odysseus the bag of winds that wreaked havoc on his journey. In Aztec theology, the god Ehecatl employed gentle zephyrs to awaken Mayahuel, the goddess of love, thereby endowing humanity with the gift of love. The Book of Genesis goes even further: when the spirit of God moves over the waters, it appears in the form of wind.
As humanity moved from myth to sci
ence, deeper thinkers sought more rational explanations. The Greek philosopher Anaximander suggested that wind was a current formed when mists were burned off by the sun. Meteorologists would say he wasn’t that far from the truth. Our contemporary understanding of wind begins with the sun, and that instinct for balance that underlies the weather.
We think of air—well, we don’t think about it at all as a rule, unless we’re running out of it. But it’s there all the time, it’s the envelope of gases that girds our planet, and within which our respiratory systems have evolved.
You might not envisage air as having weight but it does, of course: that’s what’s pushing into your face when you step outside on a windy day. It is, in fact, surprisingly heavy—the air in a normal room weighs about fifty kilograms. If you had a 25-millimetre tube going from sea level to the top of the atmosphere, the air inside it would weigh about 6.7 kilograms. Each square metre of air bears down with a force equal to a ten-tonne weight, but because the pressure in liquid or gas acts uniformly in all directions and the downward force is countered by an equivalent upward force, we don’t get squashed. When those particles of air develop a collective motion in a particular direction they become what we call wind.
It was the polymath Edmund Halley, he of the comet, who in 1686 first came up with a theory that approximates our contemporary understanding of how that motion works. Halley was struck by the correlation between information from two new sources: the data about air pressure provided by the recently invented barometer and the flow of the planetary winds reported by the mariners of the expanding British Empire. He deduced that the air along the equator was heated by the sun and lifted, to be replaced by cooler air drawn in from the temperate regions on either side of the equator— the trade winds, so crucial to the maritime industry.
Kinglake-350 Page 3
