'Angry summer': BOM left shocked by bizarre pattern
IF YOU were one of the millions of Australians who sweltered through the relentless heat of the season dubbed the "angry summer" by climatologists, you would be forgiven for not noticing the tropics have been unusually quiet this year.
More than 200 weather records tumbled across Australia this summer, according to the Climate Council, and, just six days into autumn, Cyclone Blanche brought with her yet another, when she became the first of the season to make landfall.
Blanche crossed the northern coast of Western Australia as a category 2 storm on March 6, the latest a cyclone has made landfall in Australian history, according to the Bureau of Meteorology.
It was just the third tropical low that has formed into a cyclone this season, which began on November 1, well down on the long-term season average of 11.
It is the second consecutive year Australia's cyclone count has been chronically low.
Last year, there were just three for the entire season, itself a record for the quietest cyclone count in the country's history. That, however, did not surprise scientists at the bureau.
They had tipped before the season that numbers would be low, due to the ongoing effects of an El Nino weather pattern that brings dry air, which is not conducive to the formation of a high-energy cyclone.
This year, on the other hand, the low numbers have blindsided them.
Dr Andrew Watkins, manager of climate prediction services at the bureau, said scientists are, at present, trying to get to the bottom of what happened. He said it has also attracted intrigue from international meteorologists, with visitors from the United States and the United Kingdom travelling to Australia to try to work out just what is going on.
"This year, we're not in an El Nino, we were heading into a neutral pattern," Dr Watkins said.
"We would have expected 11 or above and to only have three so far is fascinating."
They have a few theories, Dr Watkins said, and are presently crunching the data. "Many people just think tropical cyclones form over warm water, which is true, but there are other factors, a few things need to come together to form a cyclone.
"They are quite amazing things that don't form that easily. Maybe something strange is happening with one of these factors.
"Being perfectly honest, climate change is a factor in most of our climate science these days but in terms of tropical cyclones you couldn't put this season down to climate change," he said.