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Severe Tropical Cyclone Tracy was a small tropical cyclone that devastated the city of Darwin, Northern Territory, Australia, from 24 to 26 December 1974.
The small, developing easterly storm had initially appeared likely to pass clear of the city, but then turned towards it early on 24 December. After 10:00 p.m. ACST, damage became severe, and wind gusts reached 217 kilometres per hour before instruments failed. The anemometer in Darwin Airport control tower had its needle bent in half by the strength of the gusts.
Residents of Darwin were celebrating Christmas, and did not immediately acknowledge the emergency, partly because they had been alerted to an earlier cyclone (Selma) that passed west of the city, and did not affect it in any way. Additionally, news outlets had only a skeleton crew on duty over the holiday.
Tracy killed 71 people, caused $837 million in damage (1974 AUD, about $7.69 billion in 2022), or about US$5.2 billion (2022 dollars). It destroyed more than 70 percent of Darwin's buildings, including 80 percent of houses.
It left more than 25,000 out of the 47,000 inhabitants of the city homeless prior to landfall and required the evacuation of over 30,000 people, of whom many never returned. After the storm passed, the city was rebuilt using more stringent standards to cyclone code. The storm is the second-smallest tropical cyclone on record (in terms of gale-force wind diameter), behind only the North Atlantic's Tropical Storm Marco in 2008.
On 20 December 1974, the United States' ESSA-8 environmental satellite recorded a large cloud mass centred over the Arafura Sea about 370 km northeast of Darwin. This disturbance was tracked by the Darwin Weather Bureau's regional director Ray Wilkie, and by senior meteorologist Geoff Crane.
On 21 December 1974, the ESSA-8 satellite showed evidence of a newly formed circular centre near latitude 8° south and longitude 135° east. Crane -the meteorological duty officer at the time - issued the initial tropical cyclone alert, describing the storm as a tropical low that could develop into a tropical cyclone.
Later in the evening, the Darwin meteorological office received an infrared satellite image from the National Oceanic and Atmospheric Administration's satellite, NOAA-4, showing that the low pressure had developed further and that spiralling clouds could be observed. The storm was officially pronounced a tropical cyclone at around 10 p.m. on 21 December, when it was around 200 km to the north-northeast of Cape Don (360 km northeast of Darwin).
Cyclone Tracy was first observed on the Darwin radar on the morning of 22 December.
Over the next few days, the cyclone moved in a southwesterly direction, passing north of Darwin on 22 December. A broadcast on ABC Radio that day stated that Cyclone Tracy posed no immediate threat to Darwin. However, early in the morning of 24 December, Tracy rounded Cape Fourcroy on the western tip of Bathurst Island, and moved in a southeasterly direction, straight towards Darwin. The bureau's weather station at Cape Fourcroy measured a mean wind speed of 120 km/h at 9:00 that morning.
More information: Bureau of Meteorology-Australian Government
By late afternoon on 24 December, the sky over the city was heavily overcast, with low clouds, and was experiencing strong rain. Wind gusts increased in strength; between 10 p.m. (local time) and midnight, the damage became serious, and residents began to realise that the cyclone would not just pass by the city, but rather over it.
On 25 December at around 3:30 a.m., Tracy's centre crossed the coast near Fannie Bay. The highest recorded wind gust from the cyclone was 217 kilometres per hour (135 mph), which was recorded around 3:05 a.m. at Darwin Airport.
The anemometer (wind speed instrument) failed at around 3:10 a.m., with the wind vane (wind direction) destroyed after the cyclone's eye passed over. The Bureau of Meteorology's official estimates suggested that Tracy's gusts had reached 240 kilometres per hour. The lowest air pressure reading during Tracy was 950 hectopascals, which was taken at around 4 a.m., by a Bureau staff member at Darwin Airport. This was recorded during the eye of the cyclone. From around 6:30 a.m., the winds began to ease, with the rainfall ceasing at around 8:30 a.m. After making landfall, Tracy rapidly weakened, dissipating on 26 December. Total rainfall in Darwin from Cyclone Tracy was at least 255 mm.
In February 1975, Whitlam announced the creation of the Darwin Reconstruction Commission, which was given the task of rebuilding the city within five years, focusing primarily on building houses. The commission was headed by Tony Powell.
The damage to the city was so severe that some advocated moving the entire city. However, the government insisted that it be rebuilt in the same location.
By May 1975, Darwin's population had recovered somewhat, with 30,000 residing in the city. Temporary housing, caravans, hotels, and an ocean liner (MV Patris), were used to house people, because reconstruction of permanent housing had not yet begun by September that year. Ella Stack became Mayor of Darwin in May 1975 and was heavily involved in its reconstruction.
However, by the following April, and after receiving criticism for the slow speed of reconstruction, the commission had built 3,000 new homes in the nearly destroyed northern suburbs, and completed repairs to those that had survived the storm. Several new building codes were drawn up, trying to achieve the competing goals of the speedy recovery of the area and ensuring that there would be no repeat of the damage that Darwin took in 1974.
By 1978, much of the city had recovered and was able to house almost the same number of people as it had before the cyclone hit. However, by the 1980s, as many as sixty percent of Darwin's 1974 population had left, never to return. In the years that followed, Darwin was almost entirely rebuilt and now shows almost no resemblance to the pre-Tracy Darwin of December 1974.
Although a Legislative Assembly had been set up earlier in the year, the Northern Territory had only minimal self-government, with a federal minister being responsible for the Territory from Canberra. However, the cyclone and subsequent responses highlighted several problems with the way the regional government was set up. This led Malcolm Fraser, Whitlam's successor as Prime Minister, to give self-government to the Territory in 1978.
Many of the government records associated with Cyclone Tracy became publicly available on 1 January 2005 under the 30-year rule.
More information: National Archives of Australia
The sun returns; the lofty coconut trees lift up
their plumes again; man does likewise.
The great anguish is over; joy has returned;
the sea smiles like a child.
Paul Gauguin
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