NEWCASTLE and the Hunter recorded the third highest number of weather related insurance claims this spring.
Figures released by the NRMA show the region accounted for seven per cent of all extreme weather claims in NSW. This came in a season that saw a 35% increase in insurance claims for eastern states.
"Severe storms, floods, record rain and hail events have marked a spring of wild weather on Australia's east coast," Insurance Australia Group's Executive Manager for Natural Perils, Mark Leplastrier, said.
Mr Leplastrier said a La Nina weather pattern causing "more severe weather and a greater risk of flooding" was exacerbated by a negative Indian Ocean dipole.
"This means westerly winds intensify along the equator and warmer water concentrates in the eastern Indian Ocean, north-west of Australia. This increases the chances of heavier than usual rainfall over much of eastern and southern Australia, and leads to more intense storms."
According to the NRMA a "La Nina weather system occurs when there are cooler than average waters in the eastern Pacific Ocean and warmer waters in the west. This results in stronger than average winds and more moisture over northern and eastern Australia."
On top of the two weather phenomenon's identified by the NRMA, Associate Professor Andréa Taschetto of UNSW Science's Climate Change Research Centre said a Southern Annular Mode likely contributed to extreme weather.
"This increases onshore winds and chance of rain in south-east Australia", she said.
Professor Taschetto said back-to-back La Nina events over the last two years resulted in "the wettest November on record".
"Since 1950 almost half the La Nina's have occurred back to back. The most recent and extreme of which was the 2010/11 floods," she said.
"A few studies have shown that extreme La Nina events are going to become more common in the future."
Professor Ashish Sharma from the UNSW School of Civil and Environmental Engineering said "increasing global temperatures" means more rainfall.
"As temperatures rise the atmosphere can store a lot more moisture," he said.
According to Professor Sharma, this is having a mixed effect on extreme flooding events.
"On average around the world floods are decreasing because of drier soils from climate change," he said.
"But when you have consecutive La Nina events like we are seeing now, our soils and catchments are quite wet so that means much smaller rainfalls are resulting in much bigger floods."
