On 8 June 2023, the US National Oceanic and Atmospheric Administration (NOAA) declared that an expected El Niño event was underway. An El Niño event occurs when the sea surface temperatures in the central and eastern tropical Pacific are significantly warmer than average.

This warming means these areas are more likely to experience cloud development and rainfall, resulting in a shift in rainfall away from the western Pacific and eastern Australia. An El Niño event therefore typically brings drier conditions to eastern Australia, along with higher temperatures.

The key oceanic indicator for El Niño is the sea surface temperature across the central equatorial Pacific known as Niño 3.4. Based on this indicator alone, we are already experiencing El Niño conditions. A long-range sea surface temperature forecast by the Bureau of Meteorology (BoM) indicates the temperature in this region is continuing to climb, potentially beyond anything observed in the past. 

This week, BoM will release its next climate update. As we await declaration of an official El Niño event for Australia - an event that scientists are tipping could be ‘the strongest El Niño ever measured, by far’ – a group of scientists from the Climate Council describe what the pending super El Niño might look like for Australia.

Dr Simon Bradshaw, Director of Research at the Climate Council, says that climate news is “confronting”, and that we need to combat what is to come. He mentions driving down emissions to reach net zero as soon as possible and being prepared for the inevitable impact of climate change, for example learning from the past, supporting community resilience, and moving people to safer places.

There has been an unprecedented rise in sea surface temperatures since 1880. In fact, two-thirds of the warming has occurred since 1975. In 2023, we have already witnessed extraordinary changes in our ocean, an alarming loss of sea ice and a slowdown in ocean circulation. Understanding these striking trends is crucial to understanding climate change and what lies ahead.

There is likely prospect of a powerful El Niño effect forming this year. An El Niño typically brings warmer and drier conditions to eastern Australia. When a positive Indian Ocean Dipole and El Niño occur together, this drying influence is typically stronger and more widespread across Australia. This ‘drying effect’ will mean drought for Australia.

So what about the projected fire seasons in 2023 and 2024? 

Greg Mullins is an internationally recognised expert in responding to major bushfires and natural disasters, with more than 50 years’ experience as a firefighter and is the former Commissioner of Fire & Rescue NSW. He is also the founder of the Emergency Leaders for Climate Action group. 

Mr Mullins informs “On the back of three El Niña rain events (in a row) the many fuel layers regrowing”, i.e. grasses. “Areas previously unaffected by fires could be vulnerable due to the soil and vegetation drying out and becoming fuel for fires. Fires used to occur from October, but they are happening already. There are simultaneous fires seasons now, and more days of serious fire weather ahead.”

Are authorities prepared for future disasters? Mullins says “There have been big investments in response and recovery, but it still may not be possible to prepare adequately. We have to get ahead of warming or we are dooming future generations and the effects may be unrecoverable”.  

So how we can make communities more resilient to climate change? And what sort of things should governments, communities or private sector, be looking at doing? Mullins suggested taking the recommendations of the many studies undertaken. 

“For example, we need resilient power supplies for communities, perhaps solar micro grids. People need to be relocated off the flood plains. Shelters need to be cyclone rated, and flood and fire rated so that people can be safe when evacuated. Rural communities need empowering, for example farmers can help themselves with tank and pump units to assist firefighting.” There are many recommendations.

“We also need to share the knowledge we have gained from the past and educate and warn people about what’s coming.” Mullins’ says that “Victims of climate change need to prepare, and institutional support needs to change” and “we cannot continue to rely on the Australian Defence Force to prop up emergency services!”

The authorities have been unable to cope with the enormity of re-housing those affected by disasters. More effort is needed, and more money needs to be spent to strengthen communities. Mullins suggests “The government need to stop approving mines and switch the focus to protecting the community.”  

The National Emergency Management Agency held a summit in 2022 to create the Second National Action Plan for Disaster Risk Reduction, involving all parts of the community and government to create a plan of actions needed to strengthen Australia against future disasters. It’s quite clear that we need resources to fund the solutions. Could this come from a levy on the fossil fuel industry?

Rising ocean temperatures

THE FACTS: The ocean covers 70 per cent of the Earth’s surface and is continually exchanging heat, moisture and carbon with the atmosphere, creating our weather patterns. Research reveals that around 93 per cent of the excess heat in our climate system from greenhouse gas emissions has been absorbed by the ocean. The rate of ocean warming has increased dramatically in recent decades (Cheng et al. 2023).

Today, the upper 2000 metres of the ocean are absorbing over 10 zeta joules (that is, 10,000,000,000,000,000,000,000 joules) of energy every year - equivalent to 150 million Hiroshima bomb explosions. 

Rising greenhouse gases and escalating climate change are also changing the ocean’s chemistry, making it more acidic and less oxygen-rich. These ocean changes affect our weather and climate. For example, a warmer ocean surface means more energy for powerful storms. Naturally occurring climate drivers including the El Niño and La Niña events may also become stronger, amplifying drought and flood cycles. Change in ocean circulation will alter temperatures and rainfall around the world.

Unfortunately, the ocean’s immense ability to absorb and hold heat may have lulled us into a false sense of security, masking the true scale of changes in our climate system. Essentially, the ocean has been storing a problem that is now coming back to bite us.

Dr Joëlle Gergis is a Climate Council expert, author and award-winning climate scientist with the Australian National University. Dr Gergis is an internationally recognised expert in Australian and Southern Hemisphere climate variability and change. She informs that since 1980 the planet has warmed by 1.2 degrees. On the conditions and climate drivers behind a pending ‘super El Niño’, Dr Gergis says that “Australia is considered a hotspot!” 

She also cites the 2015/16 major impact of a strong El Nino on coral reefs worldwide where 75 per cent of the coral reefs were bleached and died off. “Australia – Great Barrier Reef – was on the front line.” 

“The warming of the Indian Ocean conducive to drying Australia and the changes in wind patterns, known as a positive dipole event and an El Niño, you get ‘a double-whammy’ of hot and dry conditions. It will have major impacts in our region.”

“We face a dramatic season ahead. No one is sure what effects will occur - but there is likely to be substantial impact.” 

Extreme ocean temperature anomalies 

THE FACTS: Climate change is impacting ocean circulation and ocean currents, with potentially dramatic consequences. Recent observations show that circulation in the deep waters around Antarctica has slowed by around 30 per cent since the 1990s. Circulation is slowing and since currents regulate the distribution of heat, carbon, oxygen and nutrients around the globe, this influences climate, sea levels, and the health of marine ecosystems.

The slowdown in this circulation could accelerate ice loss and sea-level rise, reduce the ocean’s ability to absorb carbon (leaving more greenhouse gases in the atmosphere), shift tropical rainbands, and deprive ecosystems near the surface of nutrients, damaging fisheries. 

In June 2023, polar scientists sounded the alarm on rapid changes in the Arctic and Antarctic (WMO 2023). Sea ice is in decline, which can disrupt ocean circulation, with serious implications not only for polar environments but for global climate and weather and affecting marine ecosystems. 

Over the last three months, sea surface temperatures in the North Atlantic have been the warmest on record for this time of year - almost a full degree above the mean. This extreme anomaly is part of a spike in sea surface temperatures globally.

Ocean scientists have long warned of declines in ocean circulation due to climate change, and even feared some features may collapse altogether in coming decades. While models had predicted a decline in circulation in the deep waters around Antarctica these recent observations show it is happening faster than projected.

Associate Professor Jan Zika is a leading Oceans, Water and Changing Climate expert at the University of New South Wales. He leads a team of researchers who use ocean observations to demonstrate that as the climate warms, wet parts of the globe are getting wetter, and dry parts are getting dryer. A/Prof Zika was a co-author on a recent Nature Reviews paper into rapidly warming oceans worldwide. 

He says that the surface temperatures are driving the weather. “The temps are the warmest ever seen – it’s crazy: they are double previous extremes. Sea Ice around Antarctica have hit the lowest amount ever seen. Greenhouse gases are causing the rate of increase of ocean warming up and up, steeper and steeper!” 

In light of the research, he also echoes Dr Bradshaw in saying “The only way to fix the escalating rate of ocean warming is to reduce greenhouse emissions.”

Dr Bradshaw says that “The 2020s decade is critical to limiting future harm and slowing the acceleration of global warming by reducing emissions to protect communities”. He suggests that Australian needs to lead change by moving from being a large fossil fuel producer and exporter to a clean energy producer and exporter and spend more on promoting clean energy than subsidising fossil fuels.

Dr Bradshaw also suggests that we also need to be investing more into building resilience in communities and listening to recommendations from the multiple royal commissions, ie. boosting emergency response capability. “There is a lot to do to address the issues” he says.

Useful links: https://knowledge.aidr.org.au/resources/second-national-action-plan-for-disaster-risk-reduction/ 

https://nema.gov.au/stories/Getting-Australia-Ready