Contributed from Victoria

Australia’s current weather pattern shows how far climate change is already changing everything. The top end experienced worse than usual flooding. The south is experiencing drought. This is reminiscent of what led to the devastating floods and bushfires of the last two decades. In fact, this trend to more frequent and severe flooding and drought has been evident since the 1970’s, and which has become increasingly pronounced over the years. Recall the events of 2016 to 2020 and the terrible bushfires of 2021.

NSW has just = experienced severe flooding. Meanwhile, Victoria continues to dry, and Euroa and Violet Town will find themselves where they will be at state 2 water restrictions within days.  

Flood and drought are not unusual for Australia. What is unusual is the severity and increasing frequency. Behind this, is the weakening El Niño and La Niña phenomena, and the impact this has on the weather patterns across the Indian and Pacific oceans.  

They are the chief determinators of Australia’s weather, via the formation of high-pressure systems high in the atmosphere. The one coming off the India ocean would regularly bring about a cloud band that would deposit rain along much of the west coast and continue toward the eastern part of Australia. This has now weakened considerably, bringing in more dry weather to the southern part of the continent.

Weather map showing high temperatures in West Australia because of the seasonal rain to come in form the Indian Ocean during May this year

The Pacific Ocean is critical to the wet and dry seasons of the northeast, which also brings on the cyclone season. This is also slowing down. The high-pressure systems are now often stalling and no moving as fast as they used to. The longer they are stuck in a position, the more water they suck out of the oceans, which is then dropped on parts of the Australian land mass.

The weather map shows he high that settled over the Tasman Sea and brought rain to the coast of NSW

One of these is now sitting over the Tasman Sea and is directly responsible for the rain in NSW and Victoria’s dry spell. It sucks water from the ocean, pushes it with the wind it generates, which is enough to bypass Victoria ad South Australia, and dump it on NSW. This high-pressure system has been in place for more than 4 days, and the signs are that another is forming to take its place.

An analysis by Australian scientists of year upon year data shows that this stalling of high-pressure systems began in the 1970’s, and has become increasingly pronounced, until it has brought us to where we are. The evidence indicates that this might by 80 percent between 2008 to 2100 along the present trajectory of carbon emission release. This will mean far more moisture in the atmosphere and more severe flooding and drought.

The immediate effect of the increasingly severe weather events the devastation in he lives and businesses of those unfortunate to be in the path. These damages hoes and communities. Before long, it flows through its impact on the economy and someway affecting everyone living in Australia.

Today’s weather patterns wear the mark of climate change. They exist because it is higher temperatures that are causing the conditions for the weakening of the El Niño and La Niña, and the stalling of pressure systems. Higher temperatures mean that atmosphere takes up more water, causes more rain in some places and drought in others.

When this is the case with a rise of just over 1.5 Centigrade, imaging what a higher rise in temperature would cause. There is no excuse for humanity to fail to take action to counter this, and Australia has a responsibility to do its part.