Australians can expect a stormy, cool and wetter than usual summer with a La Niña weather event officially confirmed.
The Bureau of Meteorology* on Tuesday declared a La Niña was underway in the tropical* Pacific after weeks of anticipation.
Last summer was also affected by the climate driver, meaning back to back La Niñas for Australia.
The weather bureau issued a La Niña “watch” on September 14, which it ramped up to a La Niña “alert” on October 12.
Much of eastern Australia has been lashed over the past two months by heavy rain and thunderstorms, which last week flooded the Lachlan River catchment* in the NSW Central West.
The La Niña weather phenomenon*, linked to the shifting pattern of sea surface temperatures through the Pacific and Indian Oceans, affects rainfall and temperature variations in Australia.
Typically it is associated with heavier rainfall for eastern, northern and central parts of the country, as well as a higher likelihood of tropical cyclones.
Eastern Australia has been hit by heavy rainfall and wild thunderstorms in October and November.
Tropical Cyclone Paddy, the first of the 2021-2022 season, formed near Christmas Island on Monday but the weather bureau said it doesn’t pose an immediate threat to the mainland or any offshore communities.
The category one system will continue to move slowly south before moving west and starting to weaken later on Tuesday.
During La Niña, waters in the central or eastern tropical Pacific become cooler than normal, persistent southeast to north-westerly winds strengthen in the tropical and equatorial* Pacific, and clouds shift to the west, closer to Australia.
Dr Andrew Watkins, the weather bureau’s head of operational climate services, said the last significant La Niña event occurred in 2010-2012, bringing widespread flooding and Australia’s wettest two-year periods on record.
“La Niña also occurred during spring and summer of 2020-21. Back-to-back La Niña events are not unusual, with around half of all past events returning for a second year,” he said.
Dr Watkins said that this year’s La Niña was not predicted to be as strong as the 2010-12 event and may even be weaker than the one that occurred last summer.
“Every La Niña has different impacts, as it is not the only climate driver to affect Australia at any one time,” he said.
“That’s why it is important not to look at it in isolation and use the bureau’s climate outlook tools online to get a sense about likely conditions for the months ahead.”
The weather bureau said this La Niña event is likely to persist until at least the end of January 2022.
- meteorology: science of the atmosphere, including weather and climate
- tropical: relating to the tropics, the region of Earth around the equator
- catchment: an area where water is collected by the natural landscape
- phenomenon: something that is known to exist or occur that is sometimes remarkable
- equatorial: relating to the equator
- What is the climate driver delivering cooler, wetter conditions called?
- Which catchment flooded last week and in what region?
- When did the last significant La Niña event occur?
- What is the name of the first cyclone of the season?
- What happens to waters in the central or eastern tropical Pacific during La Niña?
LISTEN TO THIS STORY
1. Write a story
Do you think that it is better to have a La Niña summer? List the benefits and disadvantages of having our weather affected by La Niña over the summer. Next to each item on your list, write a sentence that explains your idea.
Time: allow 20 minutes to complete this activity
Curriculum Links: English; Science; Geography
Create a resource for younger kids that helps them to understand what La Niña is. There is only one rule: you are not allowed to use any words.
Time: allow 30 minutes to complete this activity
Curriculum Links: English; Science; Geography; Visual Communication Design; Science
Summarise the article
A summary is a brief statement of the main points of something. It does not usually include extra detail or elaborate on the main points.
Use the 5W & H model to help you find the key points of this article. Read the article carefully to locate who and what this article is about, and where, when, why and how this is happening. Once you have located this information in the article, use it to write a paragraph that summarises the article.