The latest State of the Climate report is OutsideAnd there is not much good news for Australians.
Our climate has warmed by an average of 1.47 degrees since national records began, bringing the continent close to the 1.5 degree limit that the Paris Agreement hoped would never be breached. When average global warming reaches this milestone, some of Earth’s natural systems are expected to suffer Catastrophic damage.
The report, released today, paints an alarming picture of ongoing and worsening climate change. In Australia, associated effects such as extreme heat, bushfires, droughts, heavy rains and coastal inundation threaten our people and our environment.
The report is a comprehensive snapshot of the latest trends in climate, with a focus on Australia. Compiled by the Met Office and CSIRO, drawing on the latest national and international climate research.
It compiles the latest science on Australia’s climate and builds on the previous 2020 report by including, for example, information from the most recent assessment report by the Intergovernmental Panel on Climate Change.
And a take home letter? Climate change continues unabated. The world is warming, sea levels are rising, ice is melting, fiery weather is getting worse, flood rains are becoming more frequent – the list goes on.
Here’s a summary of the key findings in three main categories – and an explanation of what they all mean.
1. Warming, extreme heat, and forest fires
The 2020 report said Australia’s climate has warmed on average by 1.44 degrees since national records began in 1910. That warming has now risen to 1.47 degrees. This reverses trends across the world’s land regions, and brings with it more frequent extreme heat events.
2019 was Australia’s warmest year on record. The eight years from 2013 to 2020 are all among the ten warmest years ever measured. Warming occurs during the day and at night and in all months.
Since the 1950s, severe fire weather and a longer fire season have increased in most parts of the country. This resulted in larger and more frequent fires, especially in South Australia.
2. Rain, flood and snow
In southwestern Australia, from May to July, precipitation has decreased by 19% since 1970. In southeastern Australia, precipitation from April to October has decreased by 10% since the late 1990s.
This would be somewhat surprising given the relatively humid conditions across eastern Australia over the past few years. But don’t confuse long-term trends with year-to-year fluctuations.
Less rainfall has reduced stream flow; About 60% of water gauges around Australia show a downward trend.
At the same time, heavy rainfall events are becoming more intense – a fact not lost on residents affected by floods in Australia’s eastern states in recent months. The intensity of intense precipitation events lasting up to an hour has increased by about 10% or more in some areas in recent decades. This often leads to flash floods, especially in urban environments. The costs to society are enormous.
Warm air can contain more water vapor than cold air. This is why global warming makes heavy precipitation events more likely, even in places where average precipitation is expected to decrease.
Also since the 1950s, snow depth and snow cover and the number of snow days in alpine regions have decreased. The largest declines occur in the spring and at lower elevations.
Generally very cold days and nights are becoming less frequent across the continent. And while parts of southeast and southwest Australia have recently seen very cold nights, that’s because cold seasons are getting drier and winter nights are sharper there, resulting in more heat loss throughout the night.
Any camper will tell you how cold it can be on a clear, starry night, without the warm blanket of cloud cover.
3. Oceans and sea levels
Sea surface temperatures around the continent have increased by an average of 1.05°C since 1900. The largest rise in ocean temperature since 1970 has occurred off southeastern Australia and Tasmania. In the Tasman Sea, the rate of warming is now twice the global average.
The continued warming of the oceans has also contributed to the lengthening and frequency of marine heat waves. Marine heatwaves are wreaking havoc on ecosystems, including the Great Barrier Reef, which is at risk of destruction if nothing is done to address rising greenhouse gas emissions.
The oceans around Australia are also becoming more acidic, and that damage is accelerating. The greatest change occurs in the temperate and cooler waters of the south.
Sea levels are rising globally and around Australia. This is caused by warming oceans and melting ice. Ice loss from Greenland, Antarctica, and glaciers is increasing, and is expected to get worse.
Around Australia, the greatest sea level rise is observed in the north and southeast of the continent. This increases the risk of flooding and damage to coastal infrastructure and communities.
What is the reason for this?
All of this is happening because concentrations of greenhouse gases in the Earth’s atmosphere continue to rise. The main driver of these gases is human burning of fossil fuels. These long-lived gases form a “blanket” in the atmosphere that makes it difficult for Earth to radiate the sun’s heat back into space. Thus, the planet is warming, with costly impacts on society.
The report emphasized that carbon dioxide has been accumulating in the atmosphere at an increasing rate in recent decades. Worryingly, over the past two years, levels of methane and nitrous oxide have also grown very rapidly.
None of these problems will go away. The weather and climate in Australia will continue to change in the coming decades.
As the report states, these climate changes are increasingly affecting the lives and livelihoods of all Australians. It continues:
Australia needs to plan for and adapt to the changing nature of climate risks now and in the decades ahead. The severity of the impacts on Australians and our environment will depend on the speed with which global greenhouse gas emissions can be reduced.
This point is particularly encountered, given the Fiasco From the recent COP27 climate talks in Egypt to building on Glasgow’s commitments just a year ago to phase out fossil fuels.
It is not surprising, then, that the insurance sector is likewise Get nervous About issuing new policies for people living on the front lines of extreme weather events.
While the urgency for action has never been more urgent, we still hold the future in our hands – the choices we make today will determine our future for generations to come. Every 0.1℃ of warming we can avoid will make a huge difference.
But it’s not all bad news. Re-engineering our energy and transportation systems to be carbon neutral will create a whole new economy and job growth – with the added benefit of a safer climate future.
Do nothing, and those state of the climate reports will continue to make reading grim.