Yasi: nature’s devastating power
In the end it wasn’t as severe as it could have been as category 5 Cyclone Yasi spared Queensland’s large townships but nevertheless wreaked widespread damage between Cairns and Townsville.
As is often the case with looming natural disasters, saturated media coverage had Australasia on tenterhooks as the storm approached the Queensland Coast and reporters compared the strength of Yasi to that of an “atomic bomb” and the “amount of energy needed to power the entire world for a day”.
But scientists were certainly concerned at the unprecedented size of the cyclone, the high wind speeds it created and the potential storm surge that could have resulted as Yasi came ashore – particularly if it landed to coincide with high tide.
“The thing about Cyclone Yasi is its large diameter,” Professor Jonathan Nott of the Australasian Palaeohazards Research Unit at James Cook University told the Australian Science Media Centre.
“We commonly get ‘midgets’ in Queensland – small diameter but still intense tropical cyclones. From time to time we get one of these very, very large ones but the midgets have been more common in recent years. It makes it more unusual for us again to see a large diameter system here.”
A storm surge of up to several metres was expected along some parts of the Queensland coast, but while coastal flooding and surges in townships along the coast caused extensive damage, the strength of the storm surge was much less than anticipated.
Metservice meteorologist Bob McDavitt wrote in a blog post on Yasi that summer in Australasia continues “in a remarkable way” thanks to the presence of La Nina.
“As Yasi moved westwards and absorbed energy from the warmer-than-normal waters of the Coral Sea, its diameter expanded to 800km: much larger than the 200-300km typical of tropical cyclones in this part of the world. It intensified to Category 5 (on the Australian category scale) with gales out to 250km from its centre,” he said.
“A circle of gales 500km wide is large enough to cover most of the North or South Island. Even so, Yasi was not the largest cyclonic circulation on the planet at the time: over the last few days, a depression over the North Atlantic brought a major winter storm to the United States,” he added.
Experts on extreme weather
The recent series of extreme weather events all over the world, capped off by Yasi’s arrival, will make next week’s conference on extreme weather, to be held in Wellington, particularly topical. A joint meeting of the Australian Meteorological and Oceanographic Society and the New Zealand Meteorological Society will look at extreme weather, climate drivers, atmospheric chemistry and the impact of natural disasters with leading experts from across Australasia attending. Details of the programme are listed here.
Sections of Pink Terraces uncovered
Dr Cornel de Ronde recounted his feelings of joy this week as he explained how his team of scientists was successful in discovering an intact section of the legendary Pink Terraces in Lake Rotomahana.
The GNS Science geologist/geochemist, and recent recipient of the Prime Minister’s Science Communicator’s Prize, revealed the results of the $400,000 GNS-led survey of Lake Rotomahana at a Science Media Centre press conference in Wellington this week.
You can see the photos the underwater camera took of the section of the terraces and side scan sonar images of them here, while the briefing by Dr de Ronde and kaumatua of the Te Mana Lakes Trust is available for playback here.
The 10-day survey was primarily aimed at determining whether a geothermal system existed beneath Lake Rotomahana. Not only was a large system discovered, but the discovery of the base of the Pink Terraces constituted the first glimpse of the natural treasure since they were covered in volcanic ash and mud in the Mount Tarawera eruption of 1886.
Dr de Ronde and his fellow scientists were unable to penetrate the extensive mud covering higher parts of the terraces, but survey results indicate the remainder of the Pink Terraces are likely to also be intact.
Year of Chemistry kicks off…
Events to celebrate the International Year of Chemistry are kicking off with Sir Richard Friend, Lord Rutherford’s successor as Director of the famous Cavendish Laboratory at Cambridge University, presenting a lecture in Wellington next week to officially launch proceedings.
Around 1000 people have already registered for the lecture, indicating the level of public interest in the chemistry series.
Full details of other Year of Chemistry events are available on the Royal Society of New Zealand’s Year of Chemistry website.
Scientists will also gather in Wellington next week to discuss research efforts underway in the areas of nanotechnology and advanced materials as the MacDiarmid Institute hosts the international AMN-5 symposium.