As we all know the Australia has been facing a hard time when it comes to natural disasters. The flooding that started in November 2010 left Australia exhausted as the flood waters killed 35 people and destroyed or damaged about 30,000 homes and businesses in Queensland, leaving Brisbane inundated for days.
According to scientists the climate change maybe linked to the current La Nina through higher sea surface temperatures. The worlds’s oceans and atmosphere have gradually warmed over recent decades and this warmth could be feeding storms with an extra kick. A major global study in 2010, found that tropical cyclones might become stronger with the intensity increasing between 2 and 11 percent by 2100. While in some regions the average number of storms might decrease but the number of intense storms in category 4 and 5 range will increase, along with the rainfall and wind speeds.
Record ocean temperatures and an intense La Nina weather pattern have helped spawn one of the most powerful cyclones in Australia but whether there's a direct climate change link is less clear.
Cyclone Yasi, a maximum category 5 storm, was within hours of making landfall in far northern Queensland state and zeroing in on urban centres where more than 400,000 people live.
If it maintained its current intensity when it crossed the coast, it would be the strongest cyclone to hit Queensland since 1899, said Alan Sharp, national manager, tropical cyclone warning services, of the Australian Bureau of Meteorology.
The March 1899 cyclone struck a pearling fleet in Bathurst Bay on Cape York Peninsula, killing more than 300 people in Australia's deadliest storm.
"Yasi is not enormously unusual but it is at the top-end of the scale as far size goes as well as intensity," Sharp told Reuters from Melbourne on Wednesday.
Sharp said the current La Nina was helping drive the record ocean temperatures around Australia that were helping fuel Yasi by providing abundant heat and moisture.
La Nina events historically bring floods and an increase in cyclones during the Australian storm season from November to April.
"We can't say any particular cyclone is caused by climate change. There has been a slight trend towards more intense storms around the world," Sharp said, adding it was hard to figure out what was natural variability or climate-change related.
Scientists say there is a likely climate change link to the current La Nina through higher sea surface temperatures. The world's oceans and atmosphere have steadily warmed over recent decades and that warmth could be providing monsoons and storms with an extra kick.
A major global study in 2010, based on complex computer modelling, found that tropical cyclones will become stronger, with the intensity increasing between 2 and 11 percent by 2100.
And while in some regions, such as the western Pacific and around Australia, the average number of storms might decrease, the number of intense storms in the category 4 and 5 range will increase, along with wind speeds and the amount of rainfall.
Yasi, though, isn't the only monster cyclone to menace Australia.
Cyclone Tracy wiped out much of the city of Darwin on Christmas Day 1974, killing 71 people. The anemometer at Darwin airport recorded a gust of 217 kilometres per hour (135 miles per hour) before the instrument was destroyed, according to the Bureau of Meteorology.
Cyclone Larry ravaged the northern Queensland town of Innisfail in March 2006, becoming Australia's second costliest storm after Tracy.
Weeks later, Cyclone Monica became one of the most intense cyclones ever recorded as it moved just off the coast of the Northern Territory, sparing major townships.
Storm expected to slam into coast of Queensland tomorrow, affecting communities already saturated from months of floodingA weather satellite image obtained from the National Oceanic and Atmospheric Administration shows tropical cyclone Yasi passing the Solomon Islands while approaching the coast of Australia Photograph: Ho/Reuters
Authorities have scrambled to airlift hospital patients from the path of a cyclone roaring toward waterlogged north-eastern Australia and urged low-lying communities to evacuate because of potentially deadly flash floods.
Cyclone Yasi was expected to slam into the coast of Queensland state on Wednesday as a Category 4 storm and dump up to 3ft (1 meter) of rain on communities already saturated from months of flooding.
"This storm is huge and it is life-threatening," Queensland premier Anna Bligh said. "I know many of us will feel that Queensland has already borne about as much as we can bear when it comes to disasters and storms, but more is being asked of us and I am confident that we are able to rise to this next challenge."
Yasi was barrelling towards the Queensland state coast as a strong Category 3 storm with winds up to 137 mph (220 kph), but was expected to turn into a Category 4 storm with wind gusts up to 155mph (250km/h) by Wednesday.
Bligh said the military would airlift 250 patients from the waterfont Cairns Base and Cairns Private hospitals to Brisbane, the state capital.
Although there were no mandatory evacuation orders yet, residents in waterfront and low-lying areas from the cities of Cairns to Townsville were being advised to leave.
Ian Stewart, the state's disaster co-ordinator, said many people were deciding on their own to evacuate and that he would discuss with mayors whether forced evacuations were needed.
"In reality, we would like people to get as far south as possible, as quickly as possible, without of course breaking the rules," he told reporters.
Another storm, Cyclone Anthony, hit Queensland early yesterday but quickly weakened and did little more than uproot some trees and damage power lines.
Queensland has already suffered flooding since heavy rains started in November. The floodwaters killed 35 people, damaged or destroyed 30,000 homes and businesses and left Brisbane under water for days.
Yasi is expected to strike farther north, sparing Brisbane and other towns that suffered the worst of the recent flooding. Still, Bligh said the storm's path could change, and residents up and down the coast needed to prepare.
"We could see very powerful flash flooding that will be dangerous and potentially deadly," said Bligh, who described the storm as one of the largest and most significant cyclones the state has ever seen.
Hamilton Island off Queensland began evacuating some tourists yesterday and other resort islands were considering doing the same, Bligh said. Some nursing homes along the coast were evacuating, and residents of low-lying areas were urged to leave their homes until the storm has passed.
"We're telling anyone in the low-lying areas they need to be moving today and find another place to go to," said Val Schier, mayor of the northern Queensland city of Cairns.
Stewart said residents should be prepared with flashlights, food and water.
"Please make no mistake: this storm is a deadly event," Stewart said. "Now is the time to act."