Australian Cyclone & Tornados

The Australian cyclone season officially runs from November to April, although very few have occurred in November. The earliest cyclone to impact the northwest coast in a season was on 19 November 1910 when the eye passed over Broome. The latest cyclone was Herbie that formed near Cocos Islands and passed over Shark Bay on 21 May 1988. At the start of the cyclone season, the most likely area to be affected by tropical cyclones is the Kimberley and Pilbara coastline. Later in the season, the area threatened extends further south including the west coast. The chance of experiencing an intense category 4 or 5 cyclone is highest in March and April. Australia government in addition to having buoys in the ocean has a tropical cyclone warning services online that cover these areas,

• ·         Tropical cyclone seasonal outlook
• ·         Tropical cyclone outlook
• ·         Tropical cyclone information bulletin
• ·         Tropical cyclone watch
• ·         Tropical cyclone warning
• ·         Technical summary
• ·         Tropical cyclone forecast track map
• ·         Marine warnings

Tracks of cyclones in the Australian region from 1989/90 to 2002/03

A recent series of destructive tornadoes in Queensland, New South Wales and Victoria have shattered the myth the violent storms don't strike Australia. A review of Bureau of Meteorology data by Fairfax Regional Media has also shattered that commonly-held perception. The data, which charts recorded tornadoes between 1795 and 2012, shows more than 1200 tornadoes have killed 28 people, injured dozens and destroyed hundreds of homes and businesses. Australia has just recently just implemented a tornado warning system in its most recent hit areas. The area is also known for fire tornados. Which when the condition are just right this phenomenon happen creating an amazing spectacle.

Sources:

http://www.bom.gov.au/cyclone/about/warnings/advice.shtml

http://www.naa.gov.au/collection/fact-sheets/fs90.aspx

Australian Sinkholes

In the last year alone they have caused houses, apartment blocks, roads and even a sleeping man, to disappear into the ground without warning – and every year there are more destructive sinkholes than ever before. Mount Gambier is one of a very small handful of places in the world with the soft limestone bedrock that creates deep, circular, spectacular sinkholes like the ones found in Mexico and Florida. 

Beneath the regional center of Mount Gambier is a myriad of caves. According to Aussie geologist and sinkhole buff, Ian Lewis, the only things keeping them from collapsing are the dry conditions and relatively stable water table.In addition to southern Australia’s Limestone Coast, the northern suburbs of Perth, parts of Canberra, Newcastle, the Nullarbor Plain and western NSW have have seen sinkholes appear in recent years.Australia’s largest sinkhole has a lake at its floor and it is a popular tourist attraction, but our diving expedition to the bottom of two at Ewen's Ponds and Piccaninnie Ponds, which no one has ever been to the bottom of, revealed the caves that could be the next sinkholes waiting to happen. Preventing Sinks holes by Redirecting or Blocking Water,Treating Underground Limestone, Construction Measures, Avoid Construction on Wetlands, Seawater Treatment Facilities, Recycling Grey Water Run-off.

Humans do contribute to sinkholes and probably have ever since the invention of irrigation. Anything that has the potential to divert water into weak points beneath the earth will accelerate the creation of the pits into which houses, cars and unfortunately people sometimes fall. The drying out of the ground by abstraction or the soaking from a burst pipe are the most direct examples of human-caused sinkholes.

Sources:

http://www.theaustralian.com.au/news/the-season-for-sinkholes/story-e6frg6n6-1226597176224

http://www.smh.com.au/environment/sinkhole-swallows-southeast-queensland-beach-20110626-1gm67.html

Australian Mass Wasting

In Australia, 114 landslides are known to have caused injury or death during the period 1842 to December 2011. At least 138 people have been killed and 174 injured. The naturally-occurring events causing death varied from the fall of a single rock to spectacular debris flows and their flash flood run outs. Many landslides that killed or injured people were the result of human activity. During the period 2000-2011, over half the landslides causing injury or death were directly or indirectly human-caused. Most deaths were caused by trench and beach sand or excavation cave-ins, while most injuries were caused by edge-of-road collapses due to vehicle weight.
On 22 March 2010, intense rain brought by a severe storm triggered a debris flow from the escarpment at Kings Park, Perth, Western Australia, behind the Adelphi, Waldorf, Acacia and Park Lane apartments, causing more than 100 residents to be evacuated. Mud surrounded two vehicles and entered apartments through the windows, filling two with mud deeper than 1.2 meters. A section of the eastbound lane of Mounts Road was also closed.

What Australia is doing to prevent Landslides

• Capture and drainage of water before it reaches potential slope area
• Underground drainage by using sub-surface pipes
• Land Reform by terracing/re-shaping
• Reforestation, planting of deep rooting trees to prevent surface slips
• Ground cover with grass or agricultural crops
• Use of Gabion construction to protect water course valleys and control the flow of water down slope