‘Mature’ La Nina rumbles on, as flood claims stack up
22 November 2022
The flood-inducing La Nina weather system continues in the tropical Pacific, as insurance claims continue to roll in.
The Insurance Council of Australia (ICA) says today that 2571 claims have been lodged in relation to the most recent Central West NSW floods, which it has declared a significant event. This figure is up 18% on yesterday.
Meanwhile, the Bureau of Meteorology outlined the latest developments on the weather drivers that shape Australia’s climate.
“Atmospheric and oceanic indicators of the El Nino–Southern Oscillation reflect a mature La Nina,” it said. “Models indicate La Nina may start to ease in early 2023.”
However, the negative Indian Ocean Dipole (IOD), which can also lead to higher rainfall, has “weakened further” over the last fortnight.
“If the IOD index remains at neutral levels over the coming fortnight, the 2022 negative IOD event will have ended,” the Bureau said.
The Southern Annular Mode (SAM) is in positive phase and will likely to continue to be positive through December. During summer, a positive SAM increases the chance of above average rainfall for parts of eastern Australia.
Sea surface temperatures have remained warm, which adds to the risk. Waters in Australia’s northern tropics, and across the Coral Sea, set new October records.
“Warmer Australian waters, especially in the tropics, can result in greater evaporation, humidity, cloudiness, and rainfall.”