CLIMATE CHANGE STATE OF PLAY 2023: If this is to be Australia's Spring in 2023, what will Summer look like?

The Guardian, 1 September 2023:

On Thursday, the bureau said Australia’s spring would likely see hotter than average temperatures and lower than average rainfall – a combination that would increase the risk of bushfires.

Dr Masoud Edraki, a senior hydrologist at the bureau, said the record-high sea surface temperatures seen globally would continue to affect Australia’s weather.

“We know that a warmer climate does increase the risk of extreme weather including heatwaves and drought,” he said.

“We are already seeing longer fire seasons, and an increase in the number of dangerous fire weather days over most of Australia. We don’t know yet how global warming, and particularly the increased warmth in the oceans, is affecting our typical climate drivers.

“Our climate forecast model is consistent with the international climate forecasts that show Australia is trending dry and warm for the coming season, particularly in the south-west and much of south-eastern Australia.”

 

Australian Bureau of Meteorology (BOM), website excerpts retrieved 2 September 2023:

Global warming

Global warming continues to influence Australian and global climates. Global sea surface temperatures were highest on record for their respective months during April to July 2023, with July also being the equal-highest month on record (according to the ERA5 reanalysis). July 2023 was also the hottest month globally in terms of 2 metre air temperature.

Australia’s climate has warmed by an average of 1.47 ± 0.24 °C since national records began in 1910. There has also been a trend towards a greater proportion of rainfall from high intensity, short duration rainfall events, especially across northern Australia. Southern Australia has seen a reduction, by 10 to 20%, in cool season (April to October) rainfall in recent decades. This is due to a combination of natural variability on decadal timescales and changes in large-scale circulation caused by an increase in greenhouse gas emissions.

Warmer than median days and nights for most of Australia during spring

Issued: 31 August 2023

• For September, above median maximum temperatures are likely to very likely (60% to greater than 80% chance) across the southern two-thirds of Australia. Below median maximum temperatures are likely (60 to 80% chance) for the Queensland Gulf Country, and central and eastern NT.

• For September to November, above median maximum temperatures are very likely (greater than 80% chance) for almost all of Australia.

• For September to November, most of Australia is at least 2.5 times as likely to experience unusually high maximum temperatures (unusually high maximum temperatures equates to the warmest 20% of September to November periods from 1981 to 2018), with chances increasing to more than four times as likely for most of western and central WA and parts of the southeast.

• For September, above median minimum temperatures are likely to very likely (60% to greater than 80% chance) for Tasmania, Victoria, NSW on and east of the Great Dividing Range, the Southeast Coast of Queensland, and most of WA. Below median minimum temperatures are likely to very likely across most of the NT, the Kimberley and Northern Interior regions of WA, central and western Queensland, the far west of NSW and the North East Pastoral and Flinders districts of SA.

• For September to November, minimum temperatures are likely (60 to 80% chance) to be warmer than median for most of Australia excluding areas of north-east NT, northern Queensland, and south-east SA. Chances increase to very likely (greater than 80% chance) for Western Australia and parts of eastern Australia.

• For September to November, western and central areas of WA and areas on and east of the Great Dividing Range in NSW and Victoria are at least 3 times as likely to experience unusually high minimum temperatures (unusually high minimum temperatures equates to the warmest 20% of September to November periods from 1981 to 2018), with chances increasing to more than four times as likely for parts of central WA.

• Past accuracy of the September to November chance of above median maximum and minimum temperature long-range forecasts has been high to very high across all of Australia.

BOM: Max temperature - The chance of above median max temperature for September to November

With regard to rainfall:

For September to November, below median rainfall is likely to very likely (60% to greater than 80% chance) for most of Australia.

Later than usual rainfall onset likely for most of northern Australia

A later than usual northern rainfall onset for the 2023–24 season is likely for most of northern Australia.

Most of northern Australia excluding interior parts of Western Australia has a 60 to 70% chance of a later than usual rainfall onset. This increases to a greater than 70% chance for northern and eastern parts of the NT and Queensland, as well as along the Gascoyne Coast in WA.

The northern rainfall onset outlook gives an indication of whether the first significant rains after 1 September are likely to be earlier or later than their median date (based on historical observations, 1981–2018). View median onset dates here.

This is the final Northern Rainfall Outlook for the 2023 to 2024 season.

NOTE: The long-range forecast is influenced by several factors, including likely El Niño development and positive Indian Ocean Dipole development, and record warm oceans globally.

El Niño Alert continues, positive IOD likely for spring

The Bureau's El Niño Alert continues, with El Niño development likely during spring. When El Niño Alert criteria have been met in the past, an El Niño event has developed around 70% of the time.

Sea surface temperatures (SSTs) in the tropical Pacific are exceeding El Niño thresholds and have continued to warm slightly over the last fortnight. Climate models indicate further warming of the central to eastern Pacific is likely, with SSTs remaining above El Niño thresholds until at least early 2024.

Drought: Rainfall deficiencies and water availability

4 August 2023

• July rainfall for Australia overall was 1% above the 1961–1990 average.

• Rainfall for July was below average for southern two thirds of Western Australia, most of South Australia, eastern New South Wales, Victoria and eastern Tasmania and above average for much of the northern half of Australia.

• For the period commencing May 2023, large areas of severe rainfall deficiency (totals in the lowest 5% of historic observations since 1900) have emerged across much of the south-west half of Western Australia, and much of the east coast of New South Wales.

• For the period commencing December 2022, areas experiencing serious deficiencies (totals in the lowest 10% of observations since 1900) include parts of southern Queensland, parts of the north-eastern quarter of New South Wales and areas within the south-west of Western Australia.

• Soil moisture was below average (in the lowest 30% of all observations since 1900), across a wide band of south-west Western Australia into western South Australia, and parts of eastern Australia, particularly Wide Bay and Burnett in Queensland and along coastal New South Wales into far east Victoria.

• Low stream flows were observed mostly at sites in the west of Western Australia, areas of eastern coastal New South Wales and south-east Queensland, and scattered sites in the north of the Murray–Darling Basin.

• Storage levels remain low in some parts of south and central Queensland, eastern and southern parts of New South Wales, central Tasmania, and urban areas of Perth.

• For August to October, below median rainfall is likely to very likely (60% to greater than 80% chance) for much of Australia.

AFAC: National Council for Fire and Emergency Services, excerpt retrieved from website 2 September 2023:

Seasonal Bushfire Outlook: Spring 2023

23 August 2023

Australia's climate influences have shifted significantly since last spring, with above average temperatures and below average rainfall expected for almost the entire country for the coming season. Many regions have also seen increased fuel growth due to above average rainfall throughout recent La Niña years, which is contributing to increased risk of bushfire across locations in Australia during the spring 2023.

Increased risk of fire is expected for regions in Queensland, NSW, Victoria, SA and NT. Communities in these regions are urged to prepare for bushfire and monitor local conditions.

Australia's climate influences have shifted significantly since last spring. Following above average rainfall experienced during consecutive La Niña years, the Bureau of Meteorology predicts a switch to higher chances of above average temperatures and below average rainfall for almost the entire country.

Recent rainfall means many regions have also seen increased fuel growth, which is contributing to increased risk of bushfire for many regions of Australia during the spring season.

NOTE: Click on images to enlarge

Australian Climate Scientist Dr. Joëlle Gergis: "Unfortunately, this coming summer will be a grotesque showcase of what we can expect as our planet continues to warm. As the northern hemisphere summer comes to an end and the El Niño ramps up in the Pacific, it will be the south’s turn under the climate blowtorch."

Excerpts from an essay, “The summer ahead“ by Dr. Joëlle Gergis, ANU Fenner School of Environment and Society, writing in The Monthly, September 2023:

The climate disasters unfolding in the northern hemisphere are a sign of what’s in store here, as governments fail to act on the unfolding emergency…

As one of the few Australian climate scientists who worked on the latest United Nations’ Intergovernmental Panel on Climate Change (IPCC) global assessment report, witnessing the unrelenting procession of extreme heatwaves, floods and wildfires battering the world right now is becoming harder and harder to bear. After four years spent immersing myself in the minutiae of the global climate emergency, it’s painfully clear that the extremes we are witnessing right now are simply a prelude of what’s to come. For those of you trying to avoid the news, here’s a very quick wrap-up of what’s been going on. So far in 2023, brutal heat has swept across southern Europe, North America, China and South-East Asia. Temperatures soared to 48.2°C on the Italian island of Sardinia on July 24 – just shy of the highest temperature ever recorded in Europe – while Sanbao in China’s Xinjiang province registered 52.2°C on July 16, setting a new national temperature record. In Canada, record-breaking wildfires continue to burn enormous tracts of boreal forest, forcing 120,000 people to evacuate from their homes and polluting the air for millions of people across North America. Meanwhile, biblical rain has pounded many parts of the world, with India, Korea, Japan and China particularly hard hit. In the final days of July, the Chinese capital, Beijing, recorded its heaviest rainfall since records began 140 years ago, logging 744.8 millimetres in just 40 hours, eclipsing its average rainfall for the entire month of July. Torrential rain saw roads transformed into rivers, washing away cars and submerging the ancient courtyards of the Forbidden City in the heart of Beijing.

As the dramatic month came to an end, the World Meteorological Organization declared July 2023 the hottest month ever recorded by modern measurements. António Guterres, secretary-general of the United Nations, responded by declaring that, “The era of global warming has ended; the era of global boiling has arrived.” While cynics might dismiss his comment as hyperbole, the scientific community know he’s not wrong. Using geologic records that extend centuries back in time, scientists estimate that temperatures are now the warmest they have been in at least 125,000 years, when the Earth was last in a lull between ice ages. Current levels of carbon dioxide in the atmosphere are 418 parts per million – the highest they have been in at least two million years, around 1.7 million years before modern humans evolved. The IPCC pointedly states that human influence on the climate system is now “an established fact”. The evidence is so indisputable that it’s like stating the sky is blue or the Earth is round. Our report also concludes that virtually all of the 1.2°C of global warming we have experienced since the Industrial Revolution has been caused by human activities, namely the burning of fossil fuels. Or put another way, scientists can now definitively say that humanity’s use of coal, oil and gas is cooking the planet.

Although I’m writing this on a rainy Sunday from the safety of my peaceful home, I can still feel my anxiety rising as I pore over the technical reports detailing the mess we are in. Things are now so bad that scientists like me are starting to wonder how we can be most helpful during this time of crisis. Despite the endless demands of an academic job, many of us feel compelled to keep trying to sound the alarm, even though it often comes at great personal and professional costs. It forces us to face the confronting reality of our destabilising climate in graphic detail; it’s an unspoken occupational hazard that people in my industry now face. But because our profession demands fierce objectivity in the face of hostile scrutiny, sharing our emotional response to our work has long been considered taboo – people fear it will undermine our rationality. Scientists are often pilloried if we dare to share the emotional impact our work is having on us. But experience has taught me that when experts fail to engage authentically in public conversations about climate change, others will step in to fill the silence. Commentators unconstrained by the professional ethics and rigour of our discipline have generated rife misinformation that has led to the shameful complacency plaguing the political response to the climate change problem for decades.

As someone who understands the seriousness of what is at stake, some days it’s hard to not be consumed by despair, anger and grief…..

If I’m honest, most of the distress I feel about climate change these days does not stem from the sheer scale of the destruction we are experiencing in every corner of the world. Although watching communities and ecosystems being needlessly destroyed is incredibly difficult, the real stress comes from knowing that all the solutions we need to stabilise the Earth’s climate exist right now. One of the key messages of the IPCC’s Sixth Assessment Report is that there are options available today across all sectors that could at least halve global greenhouse gas emissions by 2030. Most of the reductions come from solar and wind energy, energy efficiency improvements and habitat conservation. Yet despite the enormous potential of these low-hanging fruit, our leaders are instead choosing to support the expansion of the fossil fuel industry to the bitter end.

Here in Australia, the sunniest continent on the planet, less than 15 per cent of our electricity is currently generated by solar power. Despite the federal government’s renewable energy target of 82 per cent by 2030, only 36 per cent of Australia’s energy is generated by clean energy sources. Instead of providing unprecedented support for the immediate deployment and scaling up of renewable energy technologies, our political leaders continue subsidising the fossil fuel industry, the culprits squarely responsible for ushering in this new era of “global boiling”. In 2022–23, Australian federal and state governments assisted fossil fuel industries with $11.1 billion in spending and tax breaks, with a particular focus on gas projects such as the Middle Arm oil and gas hub in Darwin. And just as the world’s warmest month on record came to an end, on July 31 the UK government announced its intention to grant hundreds of licences for new North Sea oil and gas extraction in an attempt to “boost British energy independence and grow the economy”. These moves blatantly ignore one of the key messages of the IPCC report, which states that around 80 per cent of coal, 50 per cent of gas and 30 per cent of oil reserves cannot be burned if warming is to be limited to 2°C. And if we want to achieve the 1.5°C Paris Agreement target, which aims to avoid unleashing millions of climate change refugees, those numbers need to be significantly lower. Banking on carbon capture and storage – a technology that currently only captures one tenth of 1 per cent of annual global carbon emissions – to reverse-engineer our way out of the problem is nothing short of insanity.

Nonetheless, expect to hear more of the carbon capture industry’s virtues during COP28, the next UN climate summit, to be held in December this year. The event is being hosted by the United Arab Emirates, one of the world’s largest oil and gas producers, and headed by Sultan Al Jaber, chief executive of the Abu Dhabi National Oil Company. Given that COP28 is being run by a top fossil fuel executive who has plans for a large expansion in his company’s production, it’s easy to feel extremely pessimistic about the likely outcomes of this meeting. It is clear that the urgency of the clean energy transition is being downplayed by vested interests with a criminal disregard for science and morality. As researcher Pascoe Sabido from the Corporate Europe Observatory bluntly observed in The Guardian: “The UN climate talks have become an oil and gas industry trade show, not the flagship for climate action. An entire industry has successfully co-opted the process and is leading us in a death spiral to climate catastrophe.”

Despite the IPCC clearly demonstrating that the burning of fossil fuels is causing the type of extreme conditions being experienced right now, our political leaders are not prepared to be brave and shut down these polluting industries fast enough to avoid locking in destructively high levels of global warming. We know – without a shadow of a doubt – that increasing levels of carbon dioxide from the use of coal, oil and gas is leading to a rise in global temperatures, which causes heatwaves to become hotter and extreme downpours more intense. Unless we urgently reduce greenhouse gas emissions, the global-scale disruption we experience in 2023 will soon be considered mild compared to what is to come. Right now, climate policies implemented globally have the world on track to warm between 2.5 and 3°C by the end of the century, with temperatures continuing to rise until we begin to drastically remove greenhouse gases from the atmosphere and reach net zero emissions. The world’s collective policies represent a catastrophic overshooting of the Paris Agreement targets, which promises to reconfigure life on our planet as we know it.

If the political commitment to achieving net zero targets ends up being nothing more than empty promises based on dodgy carbon credit accounting schemes and the “business as usual” exploitation of global fossil fuel reserves, the latest climate models show that under a very high emissions pathway, global average temperatures could warm as much as 3.3 to 5.7°C above pre-industrial levels by the end of this century, with a central estimate of 4.4°C. Under this fossil fuel–intensive scenario, land areas of Australia are projected to warm between 4 and 7°C above pre-industrial levels by 2100, with a central estimate of 5.3°C (note that, on average, Australia has already warmed 1.47°C since national records began in 1910). Such catastrophic levels of warming will render large parts of our country uninhabitable, profoundly altering life in Australia. The IPCC report patiently explains that the risk of heat extremes increases substantially with higher levels of warming. For example, heatwaves that used to occur once every 50 years on average in pre-industrial times will be nearly 10 times more frequent with 1.5°C of warming, and 40 times more likely at 4°C. Even with 1.5°C of global warming, 40 per cent of the largest cities in the world will become heat-stressed, endangering the lives of millions of people each year. Unless we rein in the burning of fossil fuels, we risk a future where humanitarian disasters are likely to play out every summer across the world.

The truth is that some scientists fear that the writing is already on the wall. If we are struggling to cope with the major disruption to society caused by the 1.2°C of global warming we have experienced so far, then what will warming of 1.5 degrees, or 2 degrees, or 3 degrees or beyond bring? Once again, the IPCC report provides detailed information on what we can expect in every single region of the globe. We know from the geologic record that 1.5 to 2°C of warming is enough to seriously reconfigure the Earth’s climate. In the past, this level of warming triggered substantial long-term melting of the Greenland and Antarctic ice sheets, unleashing six to 13 metres of global sea-level rise that lasted thousands of years. Once 2°C is passed – which could happen as early as the 2040s on our current trajectory – the only glaciers that will be left will be limited to polar areas and the highest mountain ranges, such as the Himalayas.

The current loss of ice means that we are already committed to a cascade of changes – even if we manage to stabilise our greenhouse gas emissions – as the world’s oceans reconfigure to increased influxes of meltwater, altering the behaviour of ocean currents that distribute heat around the planet. This process is now irreversible and will go on for centuries. Bear in mind that a quarter of a billion people already live on land less than two metres above sea level. The IPCC report doesn’t mince its words here, stating that beyond 2°C, adaptation is simply not possible in some low-lying coastal cities, small islands, deserts, mountains and polar regions. We are tragically unprepared for the warming that is already in the pipeline, and we haven’t seriously begun the colossal task of decarbonisation.

Unfortunately, this coming summer will be a grotesque showcase of what we can expect as our planet continues to warm. As the northern hemisphere summer comes to an end and the El Niño ramps up in the Pacific, it will be the south’s turn under the climate blowtorch. Coral reef scientists are already panicking, as global reefs are being besieged by record ocean temperatures. On July 24, sea surface temperature around the Florida Keys in the United States reached a staggering 38.4^oC, a level commonly found in a hot bath. Record heat has now triggered severe coral bleaching in the region, which has already seen 90 per cent of coral cover disappear since the 1970s. As awful as this is, these impacts are entirely consistent with what scientists expect. The IPCC warns that even with 1.5°C of warming, which we are set to breach in the early 2030s, 70 to 90 per cent of the world’s coral reefs will be destroyed. That number rises to 99 per cent with 2°C of warming, which could happen as early as the 2040s. An entire component of the Earth’s biosphere – humanity’s planetary life-support system – could be lost in under 20 years. Given that 25 per cent of all marine life depends on these areas, it’s hard to comprehend the domino effect that will be unleashed as these key ecosystems start collapsing globally…..

It’s hard not to feel cynical about the politics playing out here. According to James Cook University’s Professor Terry Hughes, one of the world’s foremost experts on coral reefs, “The Morrison government successfully lobbied individual members of the world heritage committee to ignore UNESCO’s recommendation for an in-danger listing in 2021.” And since November 2022, Labor’s environment minister, Tanya Plibersek, has been pressuring UNESCO to ignore the scientific reality of the degradation of the site, saying that there is no need to “single the Great Barrier Reef out in this way”. It’s pretty easy to understand why Australia wants to avoid an “in-danger” listing – tourism on the Great Barrier Reef supports around 65,000 jobs and generates more than $5 billion for the Australian economy each year. Any tarnishing of the reef’s condition on the world stage will cost our tourism sector dearly. But the truth is, warming ocean temperatures from the burning of fossil fuels is the biggest threat to the reef, and our government is still committed to the expansion of the very industry responsible for making things worse. No amount of political spin can hide the fact that the Great Barrier Reef is in terminal decline; we must face the fact that we are soon likely to witness the death of the largest living organism on the planet. I dread to see what this summer will bring.

As overwhelming as all of this is to take in, the imminent demise of the world’s coral reefs isn’t the only thing keeping scientists up at night right now. There is something far more sinister plaguing our minds – the possibility that the Earth might have already breached some kind of global “tipping point”. The term refers to what happens when a system crosses into a different state and stays there for a very long time, sometimes even permanently. We know that once critical thresholds in the Earth system are passed, even small changes can lead to a cascade of significantly larger transformations in other major components of the system. Key indicators of regional tipping points include dieback of major ecological communities such as the Amazon rainforest, boreal forests and coral reefs; melting of polar ice masses such as Arctic sea ice and the West Antarctic ice sheet; and disruptions to major circulation systems in the atmosphere or oceans, including changes in the North Atlantic Ocean. It’s pretty safe to say we are witnessing dramatic new developments in all of these elements right now…..

Read the complete essay at:

https://www.themonthly.com.au/issue/2023/september/jo-lle-gergis/summer-ahead