5 April 2017, ECOS, Before the storm. It’s a catastrophe in anyone’s book, not least those of insurance companies anticipating the tens of thousands of claims likely to be lodged.As the floods surged south in the days after Cyclone Debbie hit landfall near Bowen in north Queensland on March 28, a natural disaster was declared in five major centres in northern New South Wales.Citing the chairman of the Insurance Council of Australia, the Australian Financial Review said “in insurance terms, a catastrophe means a disaster that causes a significant number of claims in a region” and for Cyclone Debbie that could be claims over $1 billion. CSIRO’s Dr Chi-Hsiang Wang and colleagues have been researching the cost implications of extreme weather events but with a focus at the other end – predicting the likely cost before the storms. Counting the cost of extreme events Deloitte Access Economics last year delivered a report on building resilient infrastructure which estimated that, between 2002-03 and 2010-11, an annual average of more than $450 million was spent by Australian governments on restoring essential public infrastructure following extreme weather. If it’s business-as-usual, the report said, $17 billion is expected to be spent on direct replacement costs of essential infrastructure due to natural disasters between 2015 and 2050. These estimates don’t factor in the impacts of climate change. In the case of Cyclone Debbie, the wind intensity exceeded the limitations of the building specifications. “It’s not a surprise that we see considerable damage because the intensity is so high,” says Dr Wang. Until now, a cyclone with the force of Debbie was considered a once in a 2,000 year event by Australian design standard for wind actions (AS/NZS 1170.2:2011). That may change. “There’s a consensus among scientists, although not as strong as the consensus around rising global temperatures, that for some tropical cyclone basins around the world they are likely to see events of increased intensity,” he adds. What’s missing? Dr Wang says the current practice for wind impact assessment of physical infrastructure uses only wind intensity (in terms of wind gust) to gauge the damage potential of windstorms. “This ignores other threats brought upon by the accompanying rainfall and storm surge,” he says. Read More here