What is La Niña and how does it impact Australia?
How is it caused?
La Niña occurs when equatorial trade winds become stronger, changing ocean surface currents and drawing cooler deep water up from below. This results in a cooling of the central and eastern tropical Pacific Ocean. The enhanced trade winds also help to pile up warm surface waters in the western Pacific and north of Australia.
The warming of ocean temperatures in the western Pacific means the area becomes more favourable for rising air, clouds increasing and rain. As a result, heavy rain can occur in the north of Australia. Conversely, over the eastern and central tropical Pacific, air descends over the colder waters, meaning the region is less favourable for cloud and rain. The air rising in the west and falling in the east enhances an atmospheric circulation called the Walker circulation, resulting in changes to the globe's climate.
The reverse is true for El Niño - this leads to drought rather than heavy rainfall.
What does that mean for us here?
Flooding
As we've experienced on the eastern seaboard across New South Wales, the increase in rainfall can occasionally result in major flood events.
"The six wettest winter–spring periods on record for eastern Australia occurred during La Niña years" - BOM
Hopefully with the rain easing up now, we've seen the worst of it.
What can we do once this is all over?
Don't think that you've somehow missed the boat with harvesting rainwater or that the rest of the year will be this wet. We are still tipped to get some rain leading into winter - however - our winters are getting drier and now is the time to get yourself sorted with a rainwater tank.
Something as small as a 3500L slimline water tank can make a huge difference to the sustainability of your home. Our steel rainwater tanks are manufactured right here in Morisset, just near Newcastle in New South Wales.
We've been selling rainwater tanks across New South Wales for over 20 years - we've seen how quickly rainfall can come and go.
The best way to be on the right side of whatever weather pattern hits us - is to be prepared.