The Solution of the Quadratic Equation

We learn quite early in our mathematical education that if we consider the equation (called a quadratic)




then x has the two values






But have you ever wondered how this came about, who discovered it and why it was even considered worthy of attention in the first place? It is an interesting story that goes back at least 4000 years.

In the ancient world, mathematics was primarily a tool that was used to solve everyday problems in building and trade. A problem frequently encountered by retailers and merchants was (and still is today!) of the type

“If 6 rolls of linen cost $20, what do 8 cost?”

The approach to solving this sort of problem usually involves working out the cost of one unit and then just multiplying by the number of units required.

So we let x be the cost of one unit and we can say therefore that

6x = $20

and so

x = $20/6 = $3.33

The cost of 8 units is therefore

$8x = $26.64

This is an example of what are called “linear equations” which take the form

ax – b = 0,

and which have the solution

x = b/a (or 20/6 in our example above)

Linear equations and their solutions were well known to the Babylonians and Egyptians of the period around 2500 BC, and we know this from engraved stone tablets that have been found from the area. (Babylon was the site of one of the most advanced of the ancient civilisations and was located not far from present day Baghdad)

But the need arose to find the solution to another type of equation that was more complicated. This type of equation always emerged in problems involving areas of land, and was therefore very important in dealings concerning real estate.

This sort of problem was of the type

“We want to fence in a rectangular field of 10 square units. One side of the rectangle is 4 units less than the other side. How long are the sides of the field?”

If we say x is the length of the long side, mathematically we can express this statement as

, or


(1)


and the problem is to find x.

This type of equation (called a quadratic) is very different to a linear equation, and there is no obvious way of finding a solution.

Precisely when and who made the breakthrough is not known, but sometime in the period around 2000 BC, and probably in Babylon, a very clever technique called “substitution” was employed which finally solved the riddle of the quadratic equation. Here’s how it works.

Recalling again our general quadratic equation

(2)


we now introduce another variable y, where

(3)



Substituting this back into (2) and rearranging, we find that


or


(4)



From (3) we see that




and substituting this back into (4), followed by further rearrangement, we find that





This neat solution was one of the milestones of mathematics, and had a profound influence on the ancient world.

Incidentally you can use this technique to solve equation (1) above and find that the dimensions of our field are about 5.742 and 1.742 units. Multiply these two together and we get our 10 square units as required.

Dirk Struik remarks in his excellent “A Concise History of Mathematics”, that “although the Egyptians of this period (~2000 BC) were only able to solve simple linear equations, the Babylonians were in full possession of the technique of handling quadratic equations”.


Above: A Babylonian mosaic - c 500BC.
The Babylonians were extraordinarily advanced in art and the sciences, in particular mathematics.
Photo: Wikipedia Commons

We can therefore assume that this method has been known for at least 4000 years, but its beauty and elegance still remains fresh with us today.

We tend to think of the ancient world as a place of ignorance and primitive thought, but I wonder how many modern humans could derive this formula, from first principles, today?

For some more complicated mathematics, involving some old work on calculating pi, go to

http://passingparade-2009.blogspot.com.au/2012/04/some-nested-square-roots_19.html

Reference: “A Concise History of Mathematics” - D.J.Struik, Dover Publications 1967.

The Great Sydney Hailstorm of 1947

New Years Day 1947 looked to be like a typical Sydney summer day - hot and humid but with conditions moderated a little on the coast by the very welcome afternoon north-east sea breezes so eagerly anticipated by the locals.

Afternoon thunderstorms are not unusual for Sydney around this time of the year, and they usually begin with an increase in cloud - a type of formation called “cumulus” - over the Blue Mountains to the west of the city. Sometimes these will eventually develop into full-blown storms, which then move across the Sydney basin around mid to late afternoon.

So when cloud began to increase from the west during the late morning, it all appeared as if afternoon thunderstorms were again “on the cards”. However, there was something different in the way this storm was developing.

The Bureau of Meteorology was at that time located at Observatory Hill, which is near the south-west pylon of the Sydney Harbour Bridge. The official Bureau report noted:

“The first definite indication of cloud development at Sydney occurred towards 1300 (1pm) when cumulus commenced to build in the west and south-west. By about 1400 (2pm) this covered the south-west quadrant of the sky and appeared to be moving east, but keeping south of the city. The underpart of the cloud was mottled and serrated or curtained, rather than mammilated, and looked angrily black, while false cirrus tufts were discernible at the top”.

The cloud continued to increase across the city and become more and more menacing. The Bureau report continued -

“Shortly before the rain commenced at the Weather Bureau, shallow cumulus was observed moving from the north-east below the main cloud structure, which was coming from the westward, and between this and the overlying cloud, considerable turbulence was apparent. At this time there was a terrific noise which appeared to come from the Harbour Bridge as though several trains were passing over. It was definitely not the sound of hail or rain to the south, and it is reasonable to assume its origin was in the cloud”.

However, unknown to the Bureau at this stage, the storm had already blasted a trail of wreckage across south-western Sydney, tracking on a line from Liverpool to the southern parts of the CBD. Billiard ball sized hail sliced through rooftops, battered cars and injured pedestrians.


Left: The track of the storm across the Sydney Basin
(Click on image to enlarge)


However the full fury of the storm finally broke as it crossed the eastern suburbs, with huge hail falling through Surry Hills and the Rose Bay – Bondi area. Because of the hot temperatures, as well as the fact it was a public holiday, large crowds were swimming and sunbaking on Bondi Beach, and many injuries resulted as these unprotected people were caught in the open and pelted with hail as large as oranges.

Left: Plaster casts of the hailstones taken at the time by a dentist at Earlwood shows their massive size. (Click Image to enlarge)

The Sydney Morning Herald quoted Mr. H. Lacey, a returned soldier who was sunbaking in Bondi Beach at the time. “I thought I was back in the firing line overseas. When the hail began to fall it rattled like machine gun fire. People were lying on the ground and others were bleeding from arms and shoulders”. Fifteen year old Edna Menzies, the niece of the then leader of the Opposition and future Prime Minister, Mr. R.G.Menzies, was knocked unconscious by a hailstone “as large as a cricket ball” whilst swimming at Clovelly. She was rescued and taken to hospital, remaining unconscious as she was loaded into the ambulance.

People waiting for trains on Central Station ran for cover as hail punctured the platform rooves above them and showered them with debris. The skylight running along the entire length of the old indoor area of the station was smashed and “jagged pieces of glass up to four inches square fell among a crowd of about 100 people”.

The clock face above the station was smashed and nearby Crown Street Women’s Hospital received a badly damaged roof, terrifying both staff and women in labour. Some automobiles of the day had canvas (or “soft tops”), and many of these were holed by the hail, injuring the drivers and passengers within. Windows of trams operating across the eastern suburbs were shattered by the ice, showering passengers with broken glass.


Left: The front page of the Sydney Morning Herald,
January 2nd 1947. (Click image to enlarge)


The Sydney Morning Herald led with the story on Page 1 the next day, under the banner headline “Ice Storm Lashes City and Suburbs” and recounted a long list of the injuries and damage. Some 350 people were treated by ambulance men and hospitals as a result of hailstone impact and flying debris, particularly glass from broken windows. “For nearly three hours, ambulance wagons travelled backwards and forwards from eastern suburbs beaches with the injured” the Herald reported. Other victims were “picked up in doorways bleeding from head wounds caused by the lumps of ice and by flying glass from hundreds of broken windows”.

Fantastic scenes occurred at the Rose Bay Flying Boat Base as hail smashed the hangar roof to pieces and turned the surrounding ocean into a Pearl Harbour of churning white water. By coincidence, Bob Rice, a Sydney Sun photographer was on location and took an amazing photograph, showing the extent to which the ocean was churned up with hail, producing a dense sheet of splashes as far as the eye can see.



Large hail mashing down across the Rose Bay Flying Base, January 1st 1947. (Click image to enlarge)

Finally passing across the coast and moving out to sea, the storm left behind it a devastated city, with widespread structural damage, many personal injuries and mounds of ice that remained intact for many hours after. Numerous trees, including large swathes of Centennial Park were stripped of their leaves, producing a dank smell of rotting vegetation across the city.

Interviewed the next day, the acting State Meteorologist, Mr Newman, said “The approach of such a storm could not be forecast accurately, but it is possible that because similar conditions are expected to prevail today, that a repetition, not quite so severe, can be expected”. Happily, this second storm did not eventuate.

Sydney was staggered by the enormity of the incident, as there had not been even a remotely similar storm in living memory. Hundreds of houses had severely damaged roofs and because it was only some 18 months following the end of World War 2, there was a severe shortage of building materials. This meant that some roofs were to be left covered by tarpaulins for several years after. This, in turn, resulted in a steadily rising damage bill, as these roofs leaked whenever the tarpaulins were dislodged by strong winds and rain.

Weather forecasting in those days was severely hampered by the lack of radar imagery and satellite photography now available to the modern day weather forecasting team, and rapidly developing systems, such as thunderstorms, were difficult to deal with.

Also, the ways of distributing weather warnings were very limited and for “short term” events, such as those involved with an approaching thunderstorm, radio was the only way.

However, this was the era before portable and car radios were generally available, and this meant for those not at home, weather warnings were not easily accessible. This is a far cry from today’s situation where information is distributed through portable radios, mobile phones and SMS messages. With new technologies, involving the next generation of mobile phones, it is now possible to view current radar images surrounding all the capital cities on a mobile phone screen, and this means that the general population is now far better informed.

As far as the Bureau of Meteorology is concerned, weather forecasters now have available “state of the art”, regularly updated radar and satellite photography, and this enables accurate identification and tracking of thunderstorms to be undertaken and warnings issued - before a metropolitan area is threatened.

It was widely believed that the New Years Day storm of 1947 was a freak event, unlikely to ever happen again, but just over 52 years later, history repeated itself. Against all the odds another similar storm devastated eastern Sydney in 1999.

Reference: Australia's Natural Disasters, Richard Whitaker, New Holland Publishing
ISBN 1877069043

Goyder's Line

In nature, there are no rewards or punishments; there are consequences. -Horrace Annesley Vachell (1861-1955), British writer

An unusual contribution to the Australian weather scene during the 19th century was made by a man who was not primarily occupied with meteorology, but was in fact the Surveyor General of South Australia during the mid 1860's.

Above: George Woodroffe Goyder in 1869 (Click on image to enlarge) Photo: Wikipedia Commons

George Woodroffe Goyder was a “small man of unimpeachable character” who had come to South Australia in 1851, and by dint of hard work and attention to detail had progressed through the Colonial Engineers Office to the prestigious position of Surveyor General in 1861.

Early in the 1860’s, much of the good farming land in South Australia had already been taken up, and the government was under great pressure to open up the vast tracts of land further north towards the Flinders Rangers. Accordingly, the Surveyor General was instructed to report on the feasibility of this enterprise.

Late in 1865, at the height of a severe drought, Goyder made several trips to the north of the state, travelling over 5000 km on horseback, and noting the type of vegetation and condition of the soils.

He returned and eventually defined a line on a map - to the south of which rainfall was deemed to be reliable enough for various agricultural pursuits, but to the north, conditions were considered suitable only for grazing.

This line, which came to be known as 'Goyder's Line' ran up the eastern side of Spencer's Gulf, along the southern flank of the Flinders Rangers and then southeast, passing near Peterborough, Jamestown, Burra and Swan Reach.


The approximate position of Goyder's Line (Click on image to enlarge)

Goyder's observation on the vegetation, which coincided roughly with the southern boundary of salt-bush country in the area, had led him to believe that outside his line, farming would not be sustainable because of insufficient rainfall.

This was a bold prediction, as firstly, no detailed rainfall records were then available on which to base his belief. Secondly, it was not what the politicians of the day wanted to hear, as it put added pressure on them to make the unpopular decision of keeping the back-blocks of South Australia closed to agriculture.

Predictably enough, Goyder's Line created a turmoil of tirade and controversy including Parliamentary debate, during which it was urged that the line be pushed further north, preferably out of South Australia altogether. The line was referred to by some as “Goyder’s Line of Foolery”. It was even suggested that Goyder was on the pay-roll of the pastoralists who wanted to protect their land from agricultural farming. This was a great injustice to Goyder who was a man of “stainless steel” integrity.

However, caving into this pressure, the Government went against Goyder's advice and allowed farming allotments to be bought up well north of his line and hundreds of people began wheat farms in the northern plains of South Australia. Wheat growing became general in the districts around Port Augusta during 1877 and 1878.

As with so many other areas of human endeavor, 'Lady Luck' seemed to smile on beginners, and for the next few years, good rains came and bumper wheat crops were produced from 'the Golden North'. Wheat bags were stacked “like mountains” beside the railway line for eventual transport to Port Augusta and shipping overseas.

What Goyder had forgotten, said the farmers, was the truth of the old saying "rain follows the plough", which was a relic from the European folkloric era. By breaking up the soil, so the theory went, more moisture was released into the air and became available for rainfall.

Encouraged by this apparent success, the South Australian Government surveyed new towns to be built in the general area, such as Hammond, Bruce, Cradock, Gordon, Johnburgh, Yatina, Wilson, Carrieton, Chapmanton, Farina, and Amyton. Yatina, in particular, was ear-marked for great things, and was expected to become the biggest settlement in South Australia outside of Adelaide.

Then reality rudely arrived. Protracted drought during the early 1880's forced many wheat farmers into ruin and the rest to their knees. Most eventually walked off their land and returned to Adelaide, disillusioned and embittered.

Derelict homesteads and abandoned farm machinery still dot the area as monuments to the fact that climate cannot be ignored and must be legislated for in our day to day activities. The proposed grand city of Yatina was never able to realise it’s potential, but survived as only a few buildings, including a hotel, standing in the middle of, for what is for the most part, a desert-like landscape.

The Yatina Hotel photographed in 1974. (Image from Alan Woodward, Wikipedia Commons - click to enlarge)

Goyder had been right of course, and he had made one of the early comments on the climatology of the continent, namely that most areas of South Australia have insufficient rain to support general agriculture.

This true-color NASA MODIS image taken on September 17, 2001 shows a green vegetation pattern that closely matches Goyder's Line
(Click on Image to enlarge)

It turned out that Goyder’s line corresponded roughly with the so called “Ten Inch Line” of average rainfall, or in more modern terms the 250 mm isohyet.

The Surveyor General, in performing his task with characteristic thoroughness, had also shown the folly of attempting to modify the climate by use of Parliamentary decree.

Goyder’s work was eventually officially recognised. Today we find Goyder's Lagoon on the Birdsville Track, Goyder Railway Station, Mount Woodroffe, the highest mountain in South Australia, Wheal Goyder, a copper mine near Wallaroo and on Kangaroo Island there is the Goyder Range and the Goyder Range Branch Creek.

Reference: Australia's Natural Disasters, Richard Whitaker, New Holland Publishing 2005
ISBN 1877069043

Into the Storm - the Flight of Tango Victor Charlie

At quarter past seven in the evening of 30th November 1961, the scheduled Australian National Airways (ANA) flight Sydney to Canberra began running up its engines on the east-west runway at Sydney Airport. This was a Vickers Viscount Series 700 aircraft, with the call-sign VH-TVC or Tango Victor Charlie, and at the controls was Captain Stan Lindsay, assisted by First Officer Ben Costello, and accompanied by air hostesses Elizabeth Hardy and Aileen Keldie. Above: A Viscount with identical ANA livery to VH-TVC at Mascot Airport in 1965. Image courtesy of AussieAirliners http://www.aussieairliners.org (click image to enlarge) Also aboard were 11 other passengers, all but one Canberra residents returning home after a stay in Sydney. As the aircraft rolled into position, lightning flashed to the west and south, and almost immediately after, a huge crack of thunder shook the airport, indicating the nearby presence of a thunderstorm cell. At 7.17 pm, Lindsay released the brakes, applied full power to the four Rolls-Royce Dart engines, and the big airliner began gathering pace down the runway. Liftoff was on schedule and Tango Victor Charlie climbed quickly and soon vanished into a low overcast cloudbase at around the 250 metre level. The events of the next 5 minutes will never be precisely known, but the outcome was a watershed event, which changed the course of Australian domestic aviation, and still leaves a footprint on aircraft operating regulations today, mainly in the area of aviation radar. Radar was originally designed to detect approaching aircraft during the Battle of Britain in the early 1940’s, but it was soon noticed that showers and thunderstorms could also be detected on a radar display. Initially this was seen as a nuisance, with weather “echoes” sometimes masking aircraft movement and making detection and monitoring of aircraft traffic more difficult. But then it became obvious that radar could also be used as a short-term weather forecasting aid, and it was to eventually become standard equipment in meteorological offices around the world. Back in 1961, Sydney Airport was equipped with an Air Traffic Control (ATC) radar which was designed and used almost exclusively for directing incoming and outgoing aircraft movements. Although this radar could also “see” weather, it was not used for this purpose, and the meteorological team at the airport had no direct access to the radar display. In those days, the meteorological team at any one time consisted of three forecasters from the Bureau of Meteorology, two to prepare aviation forecasts for domestic flights and one for International. Before departure, the airline captain would receive a briefing and written weather forecast from the “Met Office” and then submit a flight plan to the Senior Operations Officer (SOO) for approval. This flight plan was then passed on to the Air Traffic Control Tower so that a firm knowledge of all outbound operations was always available. The 30th November 1961 was a day of particularly unsettled weather. A low pressure trough was located over central NSW during the morning, and this moved steadily east during the day, triggering a large area of thunderstorm activity across eastern parts of the state. Late in the afternoon, some of this activity reached Sydney, with numerous official and unofficial observations reporting the approach of thunderstorms from the west, from across the Blue Mountains. An interesting report was received from a pilot at 6.40 pm from Sylvania, who witnessed “ a thunderstorm overhead, base 1200-1500 feet. There was a half mile diameter circular opening in the base. The cloud forming the base of the thunderstorm was moving towards this opening from all directions at an estimated 50 knots. Above the opening was an inverted funnel which extended a considerable distance vertically”. Numerous other reports were received from aircraft during the afternoon, with one of the most telling from Tango Victor Charlie itself. Earlier in the day, the aircraft had flow from Canberra to Sydney, and then during the afternoon, back again, and on the approach to Sydney, at around 5.40 pm, reported “Severe continuous turbulence of a jolting nature in which the air speed indicator was fluctuating up to 15 knots either way” Captain Lindsay himself would have been aware of at least some of these reports, and certainly the nature of the turbulence encountered by Tango Victor Charlie would have been relayed back to him before his flight began. A warning of widespread thunderstorm activity across eastern NSW had also been distributed by the Met Office to the Department of Civil Aviation (DCA),and this was then widely promulgated throughout the airline companies, including Australian National Airways. Captain Lindsay’s formal pre-flight weather briefing at the Met Office also indicated the possibility of thunderstorms and heavy turbulence en-route. All in all this looked like a stand-out dangerous situation, but in fact this sort of weather was not all that unusual for November around southeast Australia, and several similar events could generally be expected at around this time each year. And for a modern aircraft like the Viscount, which was to be flown that night, such situations were thought to be well within the limits of safe operations. The Vickers Viscount was one of the success stories of post war British aviation. It was a sturdy four- engined turbo-propeller driven passenger aircraft, one of the earliest to be equipped with a fully pressurised interior, and it could cruise comfortably at 8000 metres at about 510 kph. One of the main features enjoyed by the passengers was the large window area along both sides of the cabin, which allowed for panoramic views during the flight. These windows were nearly 50% larger than those we see today, in the modern jet aircraft. The Viscount could also carry more than 50 passengers over a range of around 1500 km, and this of course meant it was ideal for the intercity runs from Sydney to Melbourne, and in this case, Sydney to Canberra. This sort of performance is modest compared with that of the modern jet airliner, but back in 1961, the Vickers Viscount was state of the art, and really had only one notable weakness. This was the lack of an on-board radar system, which enables the Captain to precisely locate thunderstorms and to avoid them in flight. Thunderstorms have long been known as an aviation safety hazard. The technical term for this form of cloud is “cumulonimbus” and in aviation circles they are known as the dreaded CB’s or “ Charlie Bravos” - the monster of the cloud family. These giant clouds frequently extend above 14 km in height, which is much higher than Mount Everest, and contain about the same energy as a small-scale nuclear weapon. Within the cloud itself there are violent up and down drafts, lightning, heavy rain and often hail also, producing a very aircraft-unfriendly environment. A large cumulonimbus formation viewed from the Space Shuttle (NASA image) (Click image to enlarge) Aviation hazards produced by thunderstorms include severe turbulence, airframe icing and possible lightning strikes, and pilots therefore avoid penetrating CB’s whenever possible. During the day, when standing in isolation, these clouds can be seen from many kilometers away and are easily avoided, but at night, when hidden by other surrounding cloud, and with no radar image to act as a guide, they become invisible hazards to all aviation operations. Soon after Tango Victor Charlie entered the cloud, there were several radio exchanges between the cockpit and the control tower, and the aircraft was instructed to begin a long, climbing, left turn out over Bondi, before returning in the opposite direction and passing back across Botany Bay at about 2500 metres, before tracking out towards Canberra. This manoeuvre was requested because of other in-bound aircraft approaching the area, and was designed to provide a safe separation distance between all the flights. But it didn’t take into account the massive thunderstorm that was still boiling over Botany Bay...... Abruptly, soon after 7.22pm, all transmissions from the aircraft ceased, and DCA then declared a Search and Rescue Operation to be in operation. With all the lightning around it was still believed that the most likely problem was a radio malfunction, but when the aircraft failed to arrive in Canberra at the expected time, it was apparent that something much more serious had occurred and the Distress Phase of the Search and Rescue Operation was declared. No progress was made that night, but soon after first light next morning some wreckage was found on the south shore of Botany Bay, and then later in the morning, the main fuselage debris was located in about 8 metres of water, in the northeast corner of the Bay. It was quickly established that there were no survivors, and the wreckage was then salvaged and taken to a hangar at the airport for analysis. A Board of Accident Inquiry was established the determine the cause of the disaster, under the Chairmanship of Mr. Justice Spicer, and the final report was made public in August 1962, after a very thorough investigation had been completed. This became known as “The Spicer Report”, and it was to have far reaching implications for aviation in Australia. After analysis of all the available evidence, Justice Spicer concluded that Tango Victor Charlie was still climbing over Botany Bay when it suddenly encountered extreme turbulence associated with the interior of a thunderstorm cell. This had caused the aircraft to descend rapidly, and in an effort regain control, Captain Lindsay had applied correctional action which resulted in severe stress on the airframe. At around 2000 metres, the starboard wing failed, and a large outer section of this separated from the aircraft. Soon after, the starboard tailplane also broke off, and the aircraft became totally out of control. With all engines still under power, the aircraft entered into a tumbling dive and struck the water at high speed, killing all aboard instantaneously. Two eyewitness accounts of what could have been the actual crash were also included in the report, although they originated from different locations and also varied considerably in their descriptions. At Penshurst, at about 7.15 pm, a witness observed “a violent electrical storm centred between Cronulla and Kurnell. At 7.25 pm there was a terrific flash of lightning, followed by two dull red objects falling slowly from the sky.” And from Chatswood at about 7.22 pm, “ there was fairly heavy electrical storm activity with thunder and lightning at frequent intervals, and heavy rain. A heavy detonation was heard, and out at 156 degrees (that is to the southeast) witness saw a yellow and blue-white glow lasting several seconds and descending fairly fast”. After sifting through the mountain of information, Justice Spicer concluded that all officers of the Department of Civil Aviation and Bureau of Meteorology had performed their duties correctly and as prescribed by the regulations, but that the regulations themselves needed changing. In particular, he recommended the development of a specialised radar weather watch at Sydney Airport, with formalised communication between Air Traffic Control and the Met Office during times of severe weather. Air Traffic Control were to then take into account the position of thunderstorms in their deliberations on traffic control, and not just consider aircraft separation alone. Another result was the requirement that all commercial passenger aircraft must carry on-board radar, to allow the Captain to be precisely aware of the position of any thunderstorms near the aircraft track. These recommendations were accepted, and eventually became part of the structure of Australian commercial aviation. A disaster of this type has never occurred again in Australia, highlighting the foresight of Justice Spicer and his Board with their work. The safety record of aviation in Australia is excellent, but as with aviation all around the world, this safety has come at a price. Tragically, the flight crew and passengers of Victor Tango Charlie had to pay a big slice of the Australian safety bill on the night of 30 November 1961. To see one of the last operational Viscounts (taken in 1996) go to http://www.youtube.com/watch?v=78bhm5gCd8Q Reference: Australia's Natural Disasters, Richard Whitaker New Holland Publishers, ISBN 1877069043

Black Saturday

On Saturday 7th February 2009 the worst bushfires in the history of Australia cut a blazing swathe of destruction across the State of Victoria. More than 170 people lost their lives, over 2000 homes were razed and people from all over Australia were stunned by the enormity of the disaster.

The Lead Up

Most of Victoria has suffered a decline in rainfall over the last decade or so. In fact many areas, including Melbourne itself, have experienced below average annual rainfall over the last twelve years often resulting in tinder dry summers.

However the summer of 2008/2009 began on an optimistic note with good rains falling over much of Victoria and South Australia. This encouraged a growth spurt in the vegetation pattern across the area.

Then the rain abruptly stopped, temperatures rose and much of south-eastern Australia, including Victoria, found itself in the grip of a rolling heatwave that persisted across the area from mid January.

The Days Before

After two weeks of record-breaking temperatures and no rain, Victoria was tinder dry with the recent December growth producing an increase in the available bushfire fuel.

Unlike other notable heatwaves of the past there was little respite, with high temperatures persisting for nearly two weeks from mid January.

Numerous temperature records were broken across Victoria, with many centres recording their highest ever temperatures between the 28th and 30th January. Over the five consecutive days from 27th to 31st January inclusive maximum temperatures were 12-15C above average across much of Victoria – a very rare if unprecedented heat wave.

On Tuesday 3rd February, the computer simulations began predicting what
both meteorologists and fire-fighters feared most. A strong cold front would move across south-eastern Australia on Saturday 7th February, preceded by hot, dry and gusty northwest winds and followed by a southwest change.

This would bring together all the ingredients of a major fire – abundant dry fuel, low humidity, strong winds, high temperatures and a wind change. The stage was set for disaster.

The Day Of The Bushfires

As the front approached Victoria on the morning of the 7th, rising northwest winds sent temperatures rocketing and the humidity plunging, fanning existing fires into infernos that rapidly jumped containment lines. Burning embers were carried aloft and transported kilometres downwind only to fall to ground and start new fires in the tinder-dry scrub.

Large tracts of central Victoria became raging firestorms that devoured everything in their path as temperatures again reached, and then surpassed, the records set only a few days before.

Melbourne’s temperature peaked at 46.4C, well above the longstanding record of 45.6C set on the day of the infamous Black Friday fires of January 13th 1939.
















Smoke from the fires was clearly visible from space as this NASA image shows. Smoke was streaming out many kilometers from the fires out across the western parts of the Tasman Sea.
(Click image to enlarge)

As the front moved across Victoria during the afternoon winds abruptly swung to the southwest, adding another dimension in unpredictability to the blazes.

The situation remained completely beyond control until temperatures fell overnight and the winds began easing. It was only then that the total devastation produced by the fires began to be understood.

Our Worst Ever Natural Disaster

Bathurst Bay is a quiet, scenic tropical port near Cape Melville on the far north Queensland coastline. But on March 4 1899, it was far from serene and was in fact the site of probably the worst natural disaster in the recorded history of Australia. It remains a shocking example of what happened in past times when there was no organised tropical cyclone warning system, when it was possible for a severe cyclone to arrive without any warning, resulting in a terrible toll of life and property.

On that day what is believed to have been a category 5 tropical cyclone smashed across the area creating a trail of havoc and destruction. A large number of vessels that comprised a pearling fleet were lying at anchor in the bay and these were all overwhelmed by the devastating winds and huge seas that arose, virtually out of nowhere. 307 sailors died in this disaster and 152 vessels were wrecked with some driven well inland by the ferocious winds.



Left: The possible path of the cyclone
(Click to enlarge)


But the cyclone also produced a massive storm surge, in fact the largest ever recorded in Australia’s history. (Some accounts actually claim that this was the largest storm surge ever recorded anywhere in the world) Storm surges are produced when very strong winds blowing from the sea to the land drive the ocean waters inland and this can produce heavy coastal flooding. The storm surge is also increased when the surrounding atmospheric pressure is very low and this produces a lifting effect on the level of the sea.

In this particular event, the orientation of the coastline is roughly east to west, and its likely that the position of the cyclone centre was just to the west of Bathurst Bay, funnelling the winds directly across the area.

This storm surge was estimated to have produced sea levels some 14 metres higher than normal and driven the ocean some 5 km inland. Over 100 indigenous Australians also died in the disaster, many drowning in the storm surge whilst trying to rescue sailors washed ashore from the pearling fleet.

There was a report later received from a captain who survived the maelstrom that his ships barometer had fallen to 914 hPa during the middle of the storm, which is one of the lowest surface pressures ever recorded.

Bizarre effects were discovered by shore parties in the following days, including the bodies of hundreds of fish and large sharks carried far inland. There was a report of dead dolphins lying some 15 metres above the beach on nearby Flinders Island.

A memorial tablet was later erected on nearby Cape Melville to mark the site of this tragic event.

Censored!

During times of war, the Government of the day is invariably conscious of how the local media is portraying the war, and above all, very concerned about the publishing or broadcasting of any material that might benefit the enemy.

During World War 2 in Australia, one of the Ministerial portfolios was “Minister for Information”, who had sweeping powers with regard to censorship, and indeed was directly in control of an important public official, the Commonwealth Censor.

In 1944, the Minister for Information was Arthur Calwell, who was serving under the then Prime Minister, John Curtin. Calwell was a highly talented politician who would eventually go on to lead the Labor party in opposition, only to miss out on becoming Prime Minister during the Federal Elections of 1961 by the narrowest of margins. Perhaps if his relations with the press had been better, things might have ended differently.




Left: Arthur Calwell - a photograph taken in 1940
(Click image to enlarge) Photo: Wikipedia Commons



Calwell was somewhat awkward in appearance and speech, and was endlessly lampooned in the newspapers, sometimes appearing in cartoons as some sort of giant parrot. Perhaps it was partly because of this, or for other unknown reasons, he detested newspapers and the media barons who ran them.

Earlier in the war, Calwell had stated “I am no believer of the so called liberty of the Press, which actually amounts to liberty for certain newspaper proprietors, who assume the right the exploit the nation and boost their own circulation”. (It is likely that many modern politicians would agree, but few would publicly express this view today).

In 1944, Sydney had begun to recover from the depths of wartime depression. Two years before, it had been a grim picture. Thousands of Australian soldiers had been killed, wounded or captured fighting the Germans and the Japanese in widespread theatres of combat. Darwin had been bombed and Sydney Harbour penetrated by Japanese submarines, convincing many that invasion was imminent, and real estate prices across the eastern suburbs plummeted as people fled inland from the coast.

However in the following two years the Allies gradually got the upper hand, and by 1944 it was considered unlikely that there would now be a Japanese invasion. The emphasis of the media gradually returned more to domestic issues.

The media of the day consisted of daily newspapers, magazines and the radio – television was 12 years way, and concepts such as privately owned computers and the Internet were too far fetched even for science fiction writers.

Daily newspapers were by far the most influential media, with a typical Sydneysider’s workday beginning with the Sydney Morning Herald or the Daily Telegraph, and then for the trip home on the train or tram, the Sun or the Daily Mirror were the universal choices.

These newspapers were run by powerful media barons, including Frank Packer (Daily Telegraph and Sunday Telegraph), Warwick Fairfax (Sydney Morning Herald), Ezra Norton (Daily Mirror), and Hugh Denison (The Sun). There was no love lost between these groups, with frequent circulation and editorial battles erupting amongst them, but they comprised most of the notoriously tough jungle of the Sydney daily newspaper scene.

However, a rather remarkable series of events was to unite these rivals in a way perhaps never seen before or since, and those events were precipitated by the Sydney Morning Herald in 1944.

In America, with the war finally running the way of the Allies, censorship had been relaxed, but in Australia, it was, if anything, tightened during 1944. Rupert Henderson, who was general manager of the Sydney Morning Herald, issued a statement that
“…..because of censorship, many American war correspondents have left Australia, and this was one reason why America is not properly informed on Australia’s policies”. Also “……that Australian correspondents have not been able to inform their papers truly of Australia’s effort”.

This statement infuriated Calwell who, in turn, issued his own release, accusing Henderson of lying and exaggerating, and threatened to call him before a Parliamentary Censorship Enquiry Committee.

When the Sydney Morning Herald and the Daily Telegraph proposed to run the story, together with Henderson’s response to Calwell, the Censor directed that all copy must be submitted to him before publication. The copy was then returned, but with Henderson’s reply heavily edited.

The Telegraph, under Frank Packer’s personal direction, then ran the story, but with blank spaces placed where the Censor had cut out information. This was a threat to one of the Censor’s most important powers – that of withholding the fact that censorship had ever taken place, and was a declaration of war on the power of the Censor.

Events then escalated quickly. Calwell ordered that all copy from the Daily Telegraph be submitted to the Censor on a daily basis before publication, and the placing of blank spaces was forbidden. The other newspapers joined in the struggle and several confrontations occurred when the Commonwealth Police arrived to prevent the distribution of newspapers, and on at least two occasions, allegedly holding newspaper staff at gunpoint. The Telegraph’s printing presses were shut down by the police, but a small number of papers were produced in midnight printing runs at the old Labour Daily plant at the corner of Brisbane and Goulburn streets in Surry Hills. (This building is still there).

Calwell became so infuriated that he ordered the Daily Telegraph and the Sydney Morning Herald off the streets altogether, followed soon after by the Melbourne Herald and the Adelaide News. This precipitated street protests in which hundreds of university students marched through Sydney streets, converging on the Censor’s office and demanding the reopening of the newspapers. There were minor clashes and a few arrests.

Frank Packer, a tough and pugnacious character, had not been idle. He convened a meeting of all the different newspaper heads in the Daily Telegraph boardroom in Castlereagh Street, where it was decided to mount a High Court challenge to the rulings of the Censor. The High Court quickly upheld this challenge and the papers were soon back on the streets.

A meeting of the full Federal Cabinet, which was about to issue a statement backing Calwell and denigrating the newspapers, was hurriedly called off when the High Court ruling came through. The crisis was over.

It was an awesome display of the power of the press, with the newspaper proprietors easily defeating an elected Cabinet Minister. The lesson of this has not been lost on following generations of politicians, who now go to great lengths to ensure generally peaceful relationships with the media. An army of PR staff and “spinmeisters” of all persuasions are employed to maintain this status quo, and it seems unlikely that such open warfare between government and press will ever occur again in Australia.