New research from artificial intelligence projects that global warming will hit the threshold of 1.5 degrees Celsius somewhere between 2033 and 2035
Scientists have long known the world is running out of time to hit its international climate targets. Now, artificial intelligence has arrived at a similar conclusion.
An innovative new AI study finds that it will take about a decade for humanity to blow past its optimistic goal of limiting global warming to 1.5 degrees Celsius.
That’s the same conclusion scientists have come to when using more conventional climate modeling techniques, but the AI research adds more evidence to the growing conviction among climate scientists and policy experts that the world is all but certain to overshoot the 1.5 C target (Climatewire, Nov. 11, 2022).
Policymakers are still striving to keep global warning well below 2 C, even if they overshoot the 1.5 C target. But even that goal is in danger, according to the AI study. It found that the 2 C threshold could approach even faster than previous research has predicted.
Part of the problem was evident at COP27, the United Nations climate conference in Egypt.
While nations’ climate negotiators were successfully fighting to “keep 1.5 alive” as the global goal in the official agreement, reached Nov. 20, 2022, some of their countries were negotiating new fossil fuel deals, driven in part by the global energy crisis. Any expansion of fossil fuels – the primary driver of climate change – makes keeping warming under 1.5 C (2.7 Fahrenheit) compared to pre-industrial times much harder.
Attempts at the climate talks to get all countries to agree to phase out coal, oil, natural gas and all fossil fuel subsidies failed. And countries have done little to strengthen their commitments to cut greenhouse gas emissions in the past year.
But all signs now point toward a scenario in which the world will overshoot the 1.5 C limit, likely by a large amount. The World Meteorological Organization estimates global temperatures have a 50-50 chance of reaching 1.5C of warming, at least temporarily, in the next five years.
There is consensusamong climate scientists, myself included, that 1.5 C of global warming is a threshold beyond which humankind would dangerously interfere with the climate system. https://ourworldindata.org/grapher/temperature-anomaly?time=earliest..latest
We know from the reconstruction of historical climate records that, over the past 12,000 years, life was able to thrive on Earth at a global annual average temperature of around 14 C (57 F). As one would expect from the behavior of a complex system, the temperatures varied, but they never warmed by more than about 1.5 C during this relatively stable climate regime.
Today, with the world 1.2 C warmer than pre-industrial times, people are already experiencing the effects of climate change in more locations, more forms and at higher frequencies and amplitudes.
Climate model projections clearly show that warming beyond 1.5 C will dramatically increase the risk of extreme weather events, more frequent wildfires with higher intensity, sea level rise, and changes in flood and drought patterns with implications for food systems collapse, among other adverse impacts. And there can be abrupt transitions, the impacts of which will result in major challenges on local to global scales. https://www.youtube.com/embed/MR6-sgRqW0k?wmode=transparent&start=0 Tipping points: Warmer ocean water is contributing to the collapse of the Thwaites Glacier, a major contributor to sea level rise with global consequences.
Steep reductions and negative emissions
Meeting the 1.5 goal at this point will require steep reductions in carbon dioxide emissions, but that alone isn’t enough. It will also require “negative emissions” to reduce the concentration of carbon dioxide that human activities have already put into the atmosphere.
Carbon dioxide lingers in the atmosphere for decades to centuries, so just stopping emissions doesn’t stop its warming effect. Technology exists that can pull carbon dioxide out of the air and lock it away. It’s still only operating at a very small scale, but corporate agreements like Microsoft’s 10-year commitment to pay for carbon removed could help scale it up.
A report in 2018 by the Intergovernmental Panel on Climate Change determined that meeting the 1.5 C goal would require cutting carbon dioxide emissions by 50% globally by 2030 – plus significant negative emissions from both technology and natural sources by 2050 up to about half of present-day emissions.
A direct air capture project in Iceland stores captured carbon dioxide underground in basalt formations, where chemical reactions mineralize it. Climeworks
A recent report by the United Nations Environment Program highlights the shortfalls. The world is on track to produce 58 gigatons of carbon dioxide-equivalent greenhouse gas emissions in 2030 – more than twice where it should be for the path to 1.5 C. The result would be an average global temperature increase of 2.7 C (4.9 F) in this century, nearly double the 1.5 C target.
Given the gap between countries’ actual commitments and the emissions cuts required to keep temperatures to 1.5 C, it appears practically impossible to stay within the 1.5 C goal.
Global emissions aren’t close to plateauing, and with the amount of carbon dioxide already in the atmosphere, it is very likely that the world will reach the 1.5 C warming level within the next five to 10 years.
With current policies and pledges, the world will far exceed the 1.5 C goal. Climate Action Tracker
How large the overshoot will be and for how long it will exist critically hinges on accelerating emissions cuts and scaling up negative emissions solutions, including carbon capture technology.
At this point, nothing short of an extraordinary and unprecedented effort to cut emissions will save the 1.5 C goal. We know what can be done – the question is whether people are ready for a radical and immediate change of the actions that lead to climate change, primarily a transformation away from a fossil fuel-based energy system.
Imagine, for a moment, a different kind of Australia. One where bushfires on the catastrophic scale of Black Summer happen almost every year. One where 50℃ days in Sydney and Melbourne are common. Where storms and flooding have violently reshaped our coastlines, and unique ecosystems have been damaged beyond recognition – including the Great Barrier Reef, which no longer exists.
Frighteningly, this is not an imaginary future dystopia. It’s a scientific projection of Australia under 3℃ of global warming – a future we must both strenuously try to avoid, but also prepare for.
The sum of current commitments under the Paris climate accord puts Earth on track for 3℃ of warming this century. Research released today by the Australian Academy of Science explores this scenario in detail.
The report, which we co-authored with colleagues, lays out the potential damage to Australia. Unless the world changes course and dramatically curbs greenhouse gas emissions, this is how bad it could get.
A spotlight on the damage
Nations signed up to the Paris Agreement collectively aim to limit global warming to well below 2℃ this century and to pursue efforts to limit temperature increase to 1.5℃. But on current emissions-reduction pledges, global temperatures are expected to far exceed these goals, reaching 2.9℃ by 2100.
Australia is the driest inhabited continent, and already has a highly variable climate of “droughts and flooding rains”. This is why of all developed nations, Australia has been identified as one of the most vulnerable to climate change.
The damage is already evident. Since records began in 1910, Australia’s average surface temperature has warmed by 1.4℃, and its open ocean areas have warmed by 1℃. Extreme events – such as storms, droughts, bushfires, heatwaves and floods – are becoming more frequent and severe.
Today’s report brings together multiple lines of evidence such as computer modelling, observed changes and historical paleoclimate studies. It gives a picture of the damage that’s already occurred, and what Australia should expect next. It shines a spotlight on four sectors: ecosystems, food production, cities and towns, and health and well-being.
In all these areas, we found the impacts of climate change are profound and accelerating rapidly.
Perth residents at an evacuation centre during a bushfire in February this year. Such events will become more frequent under climate change. Richard Wainwright/AAP
1. Ecosystems
Australia’s natural resources are directly linked to our well-being, culture and economic prosperity. Warming and changes in climate have already eroded the services ecosystems provide, and affected thousands of species.
The problems extend to the ocean, which is steadily warming. Heat stress is bleaching and killing corals, and severely damaging crucial habitats such as kelp forests and seagrass meadows. As oceans absorb carbon dioxide (CO₂) from the atmosphere, seawater is reaching record acidity levels, harming marine food webs, fisheries and aquaculture.
At 3℃ of global warming by 2100, oceans are projected to absorb five times more heat than the observed amount accumulated since 1970. Being far more acidic than today, ocean oxygen levels will decline at ever-shallower depths, affecting the distribution and abundance of marine life everywhere. At 1.5-2℃ warming, the complete loss of coral reefs is very likely.
Heat stress is killing corals and marine animal habitat. Shutterstock
Under 3℃ warming, global sea levels are projected to rise 40-80 centimetres, and by many more metres over coming centuries. Rising sea levels are already inundating low-lying coastal areas, and saltwater is intruding into freshwater wetlands. This leads to coastal erosion that amplifies storm impacts and affects both ecosystems and people.
Land and freshwater environments have been damaged by drought, fire, extreme heatwaves, invasive species and disease. An estimated 3 billion vertebrate animals were killed or displaced in the Black Summer bushfires. Some 24 million hectares burned, including 80% of the Blue Mountains World Heritage Area and 50% of Gondwana rainforests. At 3℃ of warming, the number of extreme fire days could double.
Some species are shifting to cooler latitudes or higher elevations. But most will struggle to keep up with the unprecedented rate of warming. Critical thresholds in many natural systems are likely to be exceeded as global warming reaches 1.5℃. At 2℃ and beyond, we’re likely to see the complete loss of coral reefs, and inundation of iconic ecosystems such as the World Heritage-listed Kakadu National Park.
At 3℃ of global warming, Australia’s present-day ecological systems would be unrecognisable. The first documented climate-related global extinction of a mammal, the Bramble Cay melomys from the Torres Strait, is highly unlikely to be the last. Climate change is predicted to increase extinction rates by several orders of magnitude.
Degradation of Australia’s unique ecosystems will harm the tourism and recreation industries, as well as our food security, health and culture.
There are ways to reduce the climate risk for ecosystems – many of which also benefit humans. For example, preserving and restoring mangroves protects our coasts from storms, increases carbon storage and retains fisheries habitat.
Climate change will accelerate species extinctions. Pictured: the critically endangered orange-bellied parrot. Shutterstock
2. Food production
Australian agriculture and food security already face significant risks from droughts, heatwaves, fires, floods and invasive species. At 2℃ or more of global warming, rainfall will decline and droughts in areas such as southeastern and southwestern Australia will intensify. This will reduce water availability for irrigated agriculture and increase water prices.
Heat stress affects livestock welfare, reproduction and production. Projected temperature and humidity changes suggest livestock will experience many more heat stress days each year. More frequent storms and heavy rainfall are likely to worsen erosion on grazing land and may lead to livestock loss from flooding.
Heat stress and reduced water availability will also make farms less profitable. A 3℃ global temperature increase would reduce yields of key crops by between 5% and 50%. Significant reductions are expected in oil seeds (35%), wheat (18%) and fruits and vegetables (14%).
Climate change also threatensforestry in hotter, drier regions such as southwestern Australia. There, the industry faces increased fire risks, changed rainfall patterns and growing pest populations. In cooler regions such as Tasmania and Gippsland, forestry production may increase as the climate warms. Existing plantations would change substantially under 3℃ warming.
As ocean waters warm, distributions and stock levels of commercial fish species are continuing to change. This will curb profitability. Many aquaculture fisheries may fundamentally change, relocate or cease to exist.
These changes may cause fisheries workers to suffer unemployment, mental health issues (potentially leading to suicides) and other problems. Strategic planning to create new business opportunities in these regions may reduce these risks.
Under climate change, drought will badly hurt farm profitability. Shutterstock
3. Cities and towns
Almost 90% of Australians live in cities and towns and will experience climate change in urban environments.
Under a sea level rise of 1 metre by the end of the century – a level considered plausible by federal officials – between 160,000 and 250,000 Australian properties and infrastructure are at risk of coastal flooding.
Strategies to manage the risk include less construction in high-risk areas, and protecting coastal land with sea walls, sand dunes and mangroves. But some coastal areas may have to be abandoned.
Extreme heat, bushfires and storms put strain on power stations and infrastructure. At the same time, more energy is needed for increased air conditioning use. Much of Australia’s electricity generation relies on ageing and unreliable coal-fired power stations. Extreme weather can also disrupt and damage the oil and gas industries. Diversifying energy sources and improving infrastructure will be important to ensure reliable energy supplies.
The insurance and financial sector is becoming increasingly aware of climate risk and exposure. Insurance firms face increased claims due to climate-related disasters including floods, cyclones and mega-fires. Under some scenarios, one in every 19 property owners face unaffordable insurance premiums by 2030. A 3℃ world would render many more properties and businesses uninsurable.
Cities and towns, however, can be part of the climate solution. High-density urban living leads to a lower per capita greenhouse gas emission “footprint”. Also, innovative solutions are easier to implement in urban environments.
Passive cooling techniques, such as incorporating more plants and street trees during planning, can reduce city temperatures. But these strategies may require changes to stormwater management and can take time to work.
Extreme storms will continue to violently reshape our coastlines. David Moir/ AAP
4. Human health and well-being
A 3℃ world threatens human health, livelihoods and communities. The elderly, young, unwell, and those from disadvantaged socioeconomic backgrounds are at most risk.
Heatwaves on land and sea are becoming longer, more frequent and severe. For example, at 3℃ of global warming, heatwaves in Queensland would happen as often as seven times a year, lasting 16 days on average. These cause physiological heat stress and worsen existing medical conditions.
Bushfire-related health impacts are increasing, causing deaths and exacerbating pre-existing conditions such as heart and lung disease. Tragically, we saw this unfold during Black Summer. These extreme conditions will increase at 2℃ and further at 3℃, causing direct and indirect physical and mental health issues.
Under 3℃ warming, climate damage to businesses will likely to lead to increased unemployment and possibly higher suicide rates, mental health issues and health issues relating to heat stress.
At 3°C global warming, many locations in Australia would be very difficult to inhabit due to projected water shortages.
As weather patterns change, transmission of some infectious diseases, such as Ross River virus, will become more intense. “Tropical” diseases may spread to more temperate areas across Australia.
Strategies exist to help mitigate these effects. They include improving early warning systems for extreme weather events and boosting the climate resilience of health services. Nature-based solutions, such as increasing green spaces in urban areas, will also help.
Air quality in Canberra was the worst in the world after the Black Summer fires. Lukas Coch/AAP
How to avoid catastrophe
The report acknowledges that limiting global temperatures to 1.5℃ this century is now extremely difficult. Achieving net-zero global emissions by 2050 is the absolute minimum required to to avoid the worst climate impacts.
Australia is well positioned to contribute to this global challenge. We have a well-developed industrial base, skilled workforce and vast sources of renewable energy.
But Australia must also pursue far more substantial emissions reduction. Under the Paris deal, we’ve pledged to reduce emissions by 26-28% between 2005 and 2030. Given the multiple and accelerating climate threats Australia faces, we must scale up this pledge. We must also display the international leadership and collaboration required to set Earth on a safer climate trajectory.
Our report recommends Australia immediately do the following:
join global leaders in increasing actions to urgently tackle and solve climate change
develop strategies to meet the challenges of extreme events that are increasing in intensity, frequency and scale
improve our understanding of climate impacts, including tipping points and the compounding effects of multiple stressors at global warming of 2℃ or more
systematically explore how food production and supply systems should prepare for climate change
better understand the impacts and risks of climate change for the health of Australians
introduce policies to deliver deep and rapid cuts in emissions across the economy
scale up the development and implementation of low- to zero-emissions technologies
review Australia’s capacity and flexibility to take up innovations and technology breakthroughs for transitioning to a low-emissions future
develop a better understanding of climate solutions through dialogue with Aboriginal and Torres Strait Islander peoples – particularly strategies that helped people manage Australian ecosystems for tens of thousands of years
continue to build adaptation strategies and greater commitment for meeting the challenges of change already in the climate system.
We don’t have much time to avert catastrophe. This decade must be transformational, and one where we choose a safer future.
The report upon which this article is based, The Risks to Australia of a 3°C Warmer World, was authored and reviewed by 21 experts.
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Looking into the eye of a Whale is very special.
I am not suggesting that saving whales is any real response to climate change, although of course Whales should be protected and adored. What I am suggesting is that we should hugely reduce our – i.e. human – adverse effect on this beautiful planet that is our World. We need to make huge changes to stop destroying our World.
It’s not about personal issues like riding a bike and doing away with cars (although it may have a minimal affect edit: doing away with cars would have a huge effect, aeroplanes too). Yes, we need to act local – avoid travelling excessive distances. Get a job closer to home.
The real issue is much bigger and needs to be addressed by politicians. We have to stop destroying this World. 2014 was the warmest year on record. Climate change is real and must be addressed.
