What are climate drivers?
Powerful patterns in the oceans and the atmosphere influence Australia's climate. We call these patterns our climate drivers.
Some of our climate drivers are global patterns, while others are more regional.
Their impact differs across parts of Australia and times of year. Sometimes climate drivers can work together, boosting their effect. They can also exert opposite influences and cancel each other out. It's a very complex system.
We list some of our climate drivers on this page, but there are other influences too. For example, climate change.
Video: Australian climate drivers
The El Niño Southern Oscillation, or ENSO, is a vital element of Australia's climate, representing a natural oscillation in the Pacific Ocean temperatures, wind and cloud. These oscillations between El Niño, and its opposite phase La Niña, are often the driving force behind extreme weather patterns, from searing droughts to devastating floods.
As we look to the west, we encounter the Indian Ocean Dipole, or IOD. This climate driver refers to the yearly fluctuations of tropical sea temperatures in the Indian Ocean, which can significantly impact agriculture by altering winter and spring rainfall levels. ENSO and IOD function as seasonal drivers lasting for months at a time, but there are also shorter-term climate drivers whose effects can be observed over days and weeks.
The Southern Annular Mode, or SAM, is a prominent example. SAM involves the north-south movement of westerly winds between Australia and Antarctica, often associated with storms and cold fronts that bring rainfall to southern Australia.
Another significant climate driver is the Madden–Julian Oscillation, or MJO, which influences weather in Australia's tropical north. The MJO is an eastward moving 'pulse' of cloud and rainfall near the equator, affecting the timing, development and strength of the Australian monsoon. During certain phases of a strong MJO, tropical cyclones are more likely to form.
The complex interactions among these climate drivers ensures that no two climate events or their impacts are identical. Understanding these key Australian climate drivers can help you make smarter decisions. For comprehensive insights and further information, don't hesitate to visit bom.gov.au/climate/
Australian climate influences
Blocking highs
Blocking highs are strong, slow-moving high pressure systems. They disrupt the flow of low pressure systems across southern Australia. They affect our climate in different ways, depending on their location and strength. Learn about blocking highs.
Cut-off lows
Cut-off lows are low pressure systems that break away from a main belt of low pressure south of Australia. They enhance rainfall in southern Australia. Learn about cut-off lows.
East coast lows
These intense low pressure systems form off Australia's east coast. They are most common along the coast of southern Queensland and New South Wales. They can bring heavy rainfall and strong and gusty winds to south-east Australia. Learn about east coast lows in our Severe weather knowledge centre.
Easterly troughs
Easterly troughs feature in the surface pressure patterns of eastern Australia during summer. They bring rainfall to central and inland parts of eastern Australia. Learn about easterly troughs.
El Niño and La Niña
El Niño and La Niña are part of the El Niño–Southern Oscillation (ENSO), one of our strongest climate drivers. It's a recurring pattern in the Pacific Ocean that affects global weather. Learn about El Niño and La Niña.
Frontal systems
Frontal systems bring rainfall to southern Australia. Cold fronts are the most common in Australia but we can experience warm fronts too. Learn about frontal systems.
Indian Ocean Dipole
There can be a difference between sea surface temperatures in the tropical western and eastern Indian Ocean. This difference is called the Indian Ocean Dipole. It can influence rainfall and temperature patterns over many parts of Australia. Learn about the Indian Ocean Dipole.
Madden–Julian Oscillation
This pulse of wind, enhanced cloud and rainfall cycles eastwards around the planet near the equator. It drives tropical weather around the globe. Learn how the Madden–Julian Oscillation affects Australia.
Monsoon
The monsoon is a seasonal reversal of winds over parts of the tropics. This change in winds is part of our seasons in northern Australia. Active phases of the monsoon bring heavy rainfall to northern Australia. Learn about the Australian monsoon.
North-west cloudbands
North-west cloudbands are an extensive layer of cloud. They bring rain to much of north-western, central and south-eastern Australia. Learn about north-west cloudbands.
Southern Annular Mode
The Southern Annular Mode can affect rainfall and temperature in southern Australia. It's also called the Antarctic Oscillation. Learn about the Southern Annular Mode.
Subtropical ridge
The subtropical ridge is a belt of high pressure around the globe in the middle latitudes. It brings dry and stable conditions to large parts of Australia. Learn about the subtropical ridge.
Trade winds
Trade winds are east to south-easterly winds that blow across much of the southern hemisphere tropics. They affect tropical to subtropical areas of Australia. Learn about trade winds.
Tropical cyclones and tropical lows
Tropical cyclones begin as low pressure systems called tropical lows. Learn about these climate drivers in our Tropical cyclone knowledge centre.
Upper level trough
An upper level trough is a trough of low pressure that forms in the upper level of the atmosphere. It can help cloudbands to form anywhere across the continent.
West coast trough
The west coast trough is a trough of low pressure near Australia's south-west coast. It's a semi-permanent feature of the surface pressure pattern in warmer months. Learn about the west coast trough.