Soggy summer three-peat likely as BoM issues La Nina alert
Richard Dinnen - Queensland Editor |
The Bureau of Meteorology says a La Niña weather event could form in coming months, raising the prospect of a third consecutive soggy summer.
In its latest climate driver update, the BoM said El Niño–Southern Oscillation (ENSO) ocean indicators are currently at neutral levels but show a renewed push towards La Niña.
The Bureau has raised its ENSO Outlook to La Niña ALERT, due to renewed cooling in the tropical Pacific Ocean, and climate models indicating La Niña is likely during the spring and early summer.
A La Niña forms when ocean temperatures are warmer than usual in the western Pacific with cooler waters in the east.
La Niña events increase the chances of above-average rainfall for northern and eastern Australia during spring and summer.
If the prediction is correct, Australia will experience its third consecutive La Niña year. La Niña three-peats are rare, having only occurred twice since 1950, in 1973-76 and 1998-2001.
Four of seven climate models surveyed by the Bureau suggest La Niña could return by early-to-mid spring. The other three models maintain a neutral outlook.
The BoM has already declared a negative Indian Ocean Dipole (IOD), a phenomenon that brings extra moisture from the north-west of Australia, bringing wetter conditions in the south-east.
A third consecutive wet summer could increase flood risks in eastern Australia, where dams and catchments are still close to full after prolonged rain periods that lasted well into autumn.
