Mojo – Madden-Julian Oscillation

The is the Madden-Julian Oscillation or as we like to call him, Mojo. He can have a big influence on Australia's weather and climate, especially during the warmest months of the year. Mojo runs eastward, moving a pulse of cloud and rainfall close to the equator, and travels around the Earth every 30 to 60 days.

Mojo sends a wave of weather across the Indian Ocean which can create cyclones and bring widespread rain events through parts of Australia. Scientists track these rain-making waves providing updates on the intensity and timing of the next wave.

Mojo mainly affects northern Australia, but can influence rain events further south, especially if one of Mojo's moisture waves feeds into a timely weather event down south.

Mojo's behaviour is often unpredictable, with periods of moderate to strong activity followed by periods of little or no activity, but this dog is well worth keeping an eye on.

Key things to know about the Madden-Julian Oscillation (MJO)

The Madden-Julian Oscillation is a key climate driver that effects northern Australia in summer and can be an important moisture source for southern Australia in winter.

What is the Madden-Julian Oscillation?

  • The Madden-Julian Oscillation is an easterly moving ‘pulse’ of cloud around the world near the equator.
  • It occurs in typically 30 to 60 day cycles, but strength and timing can rapidly change.
  • Enhanced rain effects are most apparent on Australia when the cloud mass is situated from our north-west to north-east.
  • In certain phases of the MJO tropical cyclones are more likely to develop and it’s has been known to kick off El Nino’s in the western Pacific by reversing the Trade Winds.

Where to go for more information?

Resources from the Bureau of Meteorology include:

Page last updated: 22 Jan 2024