Summary of Cyclone Tracy

"A tropical cyclone is defined as an intense low pressure system that forms over tropical oceans with sustained winds, exceeding gale force (63km/h) surrounding the centre. " (Northern Territory Library)

Severe tropical cyclones have maximum winds surrounding the centre exceeding hurricane force (120km/h), cyclone Tracy was classified as a ‘severe tropical cyclone’.

Tropical cyclones occur most frequently off the northwest coast of Western Australia, in the Gulf of Carpentaria and in the Coral Sea. On average about ten tropical cyclones occur in the Australian region each year and about six across the coast. Our cyclone season is from November to April and usually only four cyclones each season are classified as severe (usually out at sea), these cyclones approximately span about nine days.

Frequency of tropical cyclones in the Australian Region (Neumann 1993)

The structure of a cyclone can be broken down into four parts:

The structure of a cyclone (http://ntlapp.nt.gov.au)

-Eye, the centre of the cyclone that usually is characterised by a cloudless sky (40km in diameter)

-Eye Wall, surrounds the eye and has the most violent winds (15km in diameter)

-Spiral Bands, pattern of connective cloud bands spiralling towards the eye wall

-Cirrus Canopy, uplift of moist air within the connective clouds of the eye wall

Statistics of Cyclone Tracy

Size – 40km from the centre

Diameter of eye – 12km

Maximum wind gust - 217km/h (before the anemometer ceased functioning)

Central pressure – 950 hectopascals

Rainfall – 255mm in 12 hours

Death Toll – 65 people

Injuries - 145 serious injuries,  over 500 with minor injuries

Number of houses destroyed – 80% of Darwin

Total damage bill - $800 million

The Aftermath of Cyclone Tracy

Cyclone Tracy was classified as a category four cyclone, meaning that the wind speed was between 165-224km/h, the central pressure was between 955-931hpa and its strongest gusts were between 225-279km/h. The typical effects for a category four cyclone include:

-Significant structural damage

-Dangerous airborne debris

-Widespread power failures

-Loss of homes

Cyclone Severity Scale - (bom.gov.au)

20/12/1974 - 4pm

We are currently tracking a new possible cyclone that is positioned in the Arafura Sea, roughly 700km northeast of Darwin.  It is only a tropical low and researches are unsure whether or not anything (including a cyclone) will eventuate. It is drifting away from Darwin and so there is no threat towards the area. Over the next few days we will be tracking this tropical low and following its behavioural patterns as part of research which will help in developing a better understanding of cyclone formations.

Radar image of the possible cyclone forming off the coast of Bathurst Island. - Darwin Tropical Cyclone Warning Centre

The only places that this will be affecting could be islands near Darwin such as Croker and Bathurst Island, which will be experiencing rainfall and high wind speeds. As previously stated we are unsure as to what will eventuate from this, but we will be tracking it to make sure damage is minimised for any places that might be affected.

Shows the path of previous cyclones near Darwin. - (bom.gov.au)

23/12/74 - 3pm

The Darwin Tropical Cyclone Warning Centre issued their first alert a few days ago (21/12/74) at 4pm, suggesting that there was a possibility of a tropical cyclone developing, due to a tropical low centred 250km NNE of Croker Island. The second alert was issued at 10pm on that same day, although the report clearly states that gales were not to be expected on the coast within twenty four hours.

 At 4am the next day (22/12/74), the alerts were similar stating that Goulburn Island and Bathurst Island were alerted but there was no reason for evacuation in Darwin. After these alerts were issued, more kept coming every few hours to make sure that everyone was receiving the information. Today cyclone warning number eight was issued at 1pm, it suggested abnormal high tides and flood rains, but no major threat towards Darwin and the coast.

Radar of the cyclone in relation to Darwin - (http://ntlapp.nt.gov.au)

24/12/74 - 2pm

By early this morning radar observations showed that Tracy had changed direction and was moving south. During last night the winds started to strengthen at Cape Fourcroy on Bathurst Island and by 9 am had then backed from north northeast to northwest and reached wind speeds of 120 kilometres per hour. Only a few hours ago, we received Cyclone Warning No. 15, stating that severe tropical cyclone Tracy was centred only 115km away from Darwin and was moving south. At 12:30 pm today we received a FLASH CYCLONE WARNING, that confirmed that cyclone Tracy was now heading southeast, directly towards Darwin. Very destructive winds are to be expected throughout the afternoon and the estimated time for the inevitable direct impact will be 10 pm tonight.

Radar view of the incoming cyclone - (bom.gov.au)

“We only just had a cyclone warning 10 days ago, saying that it was coming, it was coming, and then it never came. So when we were just told that there was a new cyclone coming named ‘Tracy’, we were all a little blasé.“ - Darwin Resident

 Warnings have been issued to as many people as possible to allow for evacuation and the safety of all residents. We should expect heavy seas, high winds, storm surges, flood rains and even landslides, so please take shelter as cyclone Tracy is more serious than first anticipated!

26/12/74 - 5pm

The Aftermath of Cyclone Tracy (http://ntlapp.nt.gov.au)

Immediately, Darwin has received donations of money from community groups and the wider Australian community to help rebuild what was lost and provide essentials such as food, water and clothing. Cyclone Tracy struck at approximately 10 pm yesterday (Christmas Day) and has wiped out complete areas and caused destruction of indescribable magnitude.   Many victims have been rescued by emergency services, but the death toll of the event has now risen to 65. All personnel are urged to stay away from the area and to evacuate if close to the region as a further precaution, as there is not only massive destruction, but also dangerous circumstances. The Government has sent in armed forces immediately to help with the relief operations and provide urgent supplies and personnel. In just one day since the cyclone, the Royal Australian Air Force has airlifted 5,000 people out of Darwin to take them to safety. Fortunately the Commonwealth Government established a National Disasters Organisation earlier this year, which has allowed a surgical team and medical supplies to land in Darwin early this morning, as well as a disaster assessment team to check the damage and assist survivors.

The Government has provided evacuation and help for Darwin, to minimise anymore risks.

It has just been released that 80% of Darwin has been destroyed!

All across Australia many are providing money, food and supplies to all who need it, the people of Alice Springs have also just released that they have raised over $105,000 for immediate cash assistance for cyclone victims.

If you have any information regarding the cyclone or need help, please contact Darwin emergency services on 131 444.

Many are concerned about health issues following the cyclone yesterday, luckily the Darwin Health Services and hospitals are well prepared for situations like this. Although there are a large number of people needing medical attention, the organisation is doing everything they can to help, including establishing extra first-aid centres around Darwin and even opening congregation centres for refuge for anyone without a home. Water is constantly being delivered by tankers and will continue until Darwin is back on its feet.

Hospitals around Darwin have been opened around Darwin, to help those in need

"The combination of measures adopted, powerfully assisted by the mammoth evacuation exercise, resulted in a high standard of environmental control, which, without question, contributed to the virtual absence of disease.” – Gurd, CH (Health Management of Cyclone Tracy)

1/3/75 - 10am

Tracy struck Darwin just over three months ago, it is now that we have begun to reconstruct and clear all debris. The Government has provided money to cover the initial costs of rehabilitating Darwin and establishing a Darwin Reconstruction Commission (set up by the Whitlam Government). They are also using the cyclone to illustrate the need for a more national approach to major crises and the effective ways to plan for future events.

Two months ago Prime Minister Gough Whitlam made a pledge of “a determined and unremitting effort to rebuild your city and relieve suffering” for all of the people in Darwin. The Government’s main goal is to reconstruct Darwin within five years, depending on their strategies and plans this should be achieved.

In January Darwin’s population had dropped back to only a little over 10,000. Each day this number is increasing to the estimated 30,000 by May this year. Housing is starting to be rebuilt by thousands of construction workers that have relocated towards Darwin. Due to the large amount of workers, organisations have helped to set up “Tracy Village”, that includes housing and caravans for all workers as all working hotels and hostels are fully utilised.

No houses have yet to be rebuilt, however it is planned to have all demolition and the removal of debris done by September this year. The main priority for rebuilding homes is that they would have to be built to a certain new standard. The plan has been set up by the Government, they have plans to achieve the quality and integrity of housing as well as through a reasonable time frame and at a realistic cost.  One of the major requirements for the building is that all roofs must be tied to the foundations and be clad to protect against flying debris. This building code will hopefully prevent further damage of homes, during cyclones and storms.

Economic Impacts- Darwin's population went from 45000 to 10500 as many people did not return after the cyclone, this had a major impact on the local economy.
- Up to 80% of buildings were destroyed and lost
- Estimated cost of disaster $800 million (1974)
- Major damage to infrastructure (roads, electricity supply etc.)

Social Impacts- Claimed 65 lives (49 city & 16 sea)
- Approximately 650 people were treated for injuries
- Many people were placed under large amounts of stress due to loss of relatives, friends and property
- More than 35000 people evacuated

Environmental Impacts
- Large amounts of vegetation destroyed (thousands of trees and plants)

In the long term the main things that both non-Government and Government organisations are considering include:

-         Rebuilding

-         Infrastructure development

-         Warning systems

-         Education to be improved

25/12/75 - 10am

One year on from the horrific cyclone Tracy, we have begun to see a big improvement with the reconstruction of Darwin. The Government has followed through with their ‘Reconstruction Commission’ and are looking at only another two years of building, therefore reducing the rebuilding process by two years. The cyclone caused over $800 million in damage, meaning that there was not much left standing in Darwin after the event occurred. The Government has provided an estimated total of $300 million to rebuild Darwin’s entire infrastructure, but it is thought that the entire project will cost another few million dollars to finish to the building standards required. Darwin’s Police, Ambulance and Fire Brigade played a key role in the management of the cyclone assistance, helping with not only the clean-up, but also supporting all within the community and seeking out help. Many individuals also risked their lives after the event to help others and save the community, mirroring the Australian idea of mateship.

Prevention for the future is one of the major issues that is being tackled by many organisations across Australia. It is said that both the Government and other small companies are working together to create better warning systems and programs that will help to spread the news of future cyclones and natural disasters faster. Educational programs are also being created to teach locals in cyclone prone areas about evacuation and the use of safety equipment such as bunkers. It is planned that everyone will have enough knowledge to be better prepared before the next big cyclone.

The cyclone caused some terrible outcomes for many different people across Darwin, but certain people experienced different levels of impact. Anyone that lived closer to the eye wall of the cyclone had a more substantial amount of damage and were put in the most danger, due to the violent winds and heavy rainfall. Many of these people were part of the 65 killed in the event.

Bibliography

Cyclone Tracy. (1999). Retrieved October 4th, 2013, from http://www.historysmiths.com.au/CentFedPlayKit/events/nature/1974_cyclone%20tracy.htm

Cyclone Tracy. (2004). Retrieved October 4th, 2013, from abc Northern Territory: http://www.abc.net.au/nt/stories/s1255740.htm

Cyclone Tracy. (2010). Retrieved September 29th, 2013, from Northern Territory Library: http://ntlapp.nt.gov.au/tracy/advanced/Cyc_Tracy.html

Google. (2013). Retrieved October 1st, 2013, from http://www.google.com.au

Historical Disasters. (2013). Retrieved September 20th, 2013, from Australian Government: http://www.em.gov.au/library/Onlineresources/Historicaldisasters/Pages/HistoricalDisastersCycloneTracy.aspx

Severe Tropical Cyclone Tracy. (2013). Retrieved October 3rd, 2013, from Bureau of Meteorology: http://www.bom.gov.au/cyclone/history/tracy.shtml

Government, A. (2013). Cyclone Tracy. Retrieved September 30th, 2013, from http://www.naa.gov.au/collection/fact-sheets/fs176.aspx

The Aftermath of Cyclone Tracy - (bom.gov.au)