Some of the extreme weather events in the past year are being blamed on the El Nino weather cycle.
It has contributed to the warmest year on record in 2015, and now the cycle is expected to continue into the New Year.
Lydia Feng reports.
As the calendar turns to 2016, much of Australia has been sweltering through unseasonably hot weather over a considerable spell now.
New South Wales recorded one of its warmest years on record in 2015.
Adelaide ended the year with its hottest December.
And temperatures were at their second-highest in Melbourne.
The director of the Centre of Excellence for Climate System Science at the University of New South Wales, Andy Pitman, predicts the unusual heat will continue into this year.
Professor Pitman says naturally occurring El Nino weather changes have exacerbated drier conditions in much of the country.
"When you get a big El Nino in the southern hemisphere, it tends to cause quite significant warming over the hemisphere. So you tend to see, particularly on the east coast of Australia, much warmer temperatures and drier than average conditions. On the west coast of Australia, you tend to see wetter conditions and relatively cooler conditions, because there's more water, more evaporation, more cloud."
The phenomenon has been linked to extreme weather around the world, with major flooding in countries such as Paraguay, Britain and the United States.
But Professor Adam Scaife from Britain's Met Office predicted at the end of year that the trend would break in Britain.
"We're on course for the warmest December in more than a hundred years of records and the wettest December for many parts of the UK, including Scotland, Wales and north-west England in more than a hundred years. But we don't expect those conditions to continue right through to the end of winter."
In the United States, flooding at the turn of the year turned roadways in the midwestern state of Missouri into rivers.
In South America, tens of thousands of people were displaced in Paraguay, Argentina, Uruguay and Brazil as they experienced one of their worst floods in 50 years.
Now, NASA has released a satellite image showing warm water in the eastern Pacific Ocean rising as much as 25 centimetres above normal.
And that is happening on a scale large enough to disturb weather patterns right around the globe.
Some science experts are saying, while the El Nino has already wrecked havoc around the world, its impact is far from over and still yet to peak.
In Sydney, Professor Andy Pitman says he expects the hot weather to continue in the new year in Australia.
"In 2016, we do anticipate it to be the hottest year on record and likely to be dry. That does translate into particularly high bushfire risk. And the best thing anyone can do around bushfire risk, if you're living in the cities particularly, is look to see that your own property is protected and you have a really well-developed bushfire plan."
