ENSO
ENSO refers to changes in sea surface temperatures and atmospheric pressure across which ocean?
The Pacific Ocean.
The IOD refers to changes in sea surface temperatures across which ocean?
The Indian Ocean.
SAM refers to the north–south movement of strong westerly winds circling which continent?
Antarctica.
During an El Niño event, eastern Australia usually experiences this type of rainfall pattern.
Drier than average conditions (reduced rainfall).
A positive IOD typically brings what kind of conditions to Australia?
Drier conditions and drought.
When SAM is in a positive phase, what generally happens to rainfall in southeast Australia during spring and summer?
Rainfall increases (due to moist onshore winds moving further south).
The opposite of El Niño, which brings increased rainfall to eastern Australia, is called what?
La Niña.
The negative IOD phase often brings what to southern and central Australia?
Above-average rainfall and flooding risk.
A negative SAM phase in winter usually causes stronger westerly winds that bring what type of weather to southern Australia?
Cold fronts, storms, and increased rainfall.
What atmospheric pressure system is closely linked to ENSO and is measured at Darwin and Tahiti?
The Southern Oscillation Index (SOI).
The IOD can interact with ENSO. A positive IOD combined with El Niño usually causes what?
severe drought conditions in Australia.
Positive SAM in summer often leads to increased risk of what hazard in southeast Australia due to dry inland conditions?
Bushfires
During La Niña, trade winds strengthen. This pushes warm water in which direction across the Pacific?
Westward (towards Australia and Indonesia).
Which countries on the western side of the Indian Ocean typically experience heavy rainfall during a positive IOD?
East African nations
SAM strongly influences rainfall in the Murray–Darling Basin. Explain why.
Because shifts in westerly winds affect whether moisture is carried inland or diverted south, directly impacting rainfall in the basin.