This latest record is a wakeup call to all governments to implement effective climate change policy. A hotter planet – especially for a country like Australia – means more water scarcity, worse droughts, higher risk of bushfires, poorer mental and physical health, higher suicide and huge ecological loss. We need to do better with incentivising change, with our best policy mix including regulations, carbon emission pricing and markets. There is much policy research out there to lead the way.

Since 2014 was identified as the (then) warmest recorded year, that record has been broken four times in a decade –  in 2015, 2016, 2023 and now in 2024. In each case, the record was broken by at least 0.10°C and the 2024 temperature was more than 0.5°C warmer than ten years ago. Warming has clearly accelerated.

During that time, global-scale ocean heating has driven two multi-year global coral bleaching events, a concept that was not apparent 50 years ago. The high levels of coral mortality observed on reefs around the world are disrupting the functions of coral reef ecosystems.

While some species have recovered following heat events, they are the most affected by the next heatwave. Importantly, this is a human issue – around one billion people rely directly upon healthy coral reefs for their lives or livelihoods, which are increasingly at risk as climate change continues.  It is imperative that we urgently reduce the greenhouse gas emissions that are the primary cause of climate change.

While climate trends can't be fully understood by focusing on just one year, the news that 2024 has surpassed 1.5°C above pre-industrial levels for the first time is deeply concerning. This, coupled with the rise in global temperatures and increasing impacts that we have been seeing over the first part of the 21st century, highlights the urgency of the situation.

While ‘global temperatures’ and ‘1.5°C above pre-industrial levels’ may seem quite remote and arbitrary, we hear on the news or ourselves experience the effects of human-driven climate change every day – events such as hotter days, heatwaves, wildfires, heavy rain and flooding. As scientists, we also see the clear fingerprints of human-driven climate change on large scale atmospheric processes, like changes in the location of high-pressure systems and the poleward shift of Southern Ocean westerly winds which bring cold fronts and rain to southern and southwestern Australia, where declining rainfall in southwest Australia’s Wheatbelt has an impact on both water and food security.

While the science is clear that we are in trouble, there is still hope. The time to act is now.

Extreme and unseasonal temperature and precipitation events have increased worldwide. The greater frequency and variability of floods, heatwaves, and droughts challenge traditional definitions of climate periods as 30-year means. For some regions we know both the local and remote climate drivers, amplified by global warming. Their impacts include longer, hotter warm seasons and shorter, drier wet seasons in Australia’s southern Mediterranean climate regions. In contrast, flooding has increased in coastal eastern Australia.

The poleward contraction of mid-latitude westerly winds is a readily identifiable contributor. Improvements in climate models are expected to more accurately predict future phases of climate drivers. Because global warming is not uniform across the Earth’s surface, the revised definitions into shorter periods of climate will vary by region.

The WMO’s press release on the record global temperature of 2024 is no surprise. Although WMO notes the temperature goal of the Paris Agreement is “not yet dead” this is only true technically. Furthermore, many climate experts cling to hope that the global temperatures will only temporarily overshoot the 1.5 °C goal. Unfortunately, this too is wishful thinking. 

We are in the early stages of an emergency that endangers planetary civilisation. Climate change is not only a symptom of peril, but contributes to adverse social and ecological consequences that cause additional risk. Combined, these adverse feedbacks are like magnets, pulling civilisation ever closer to its collapse. For example, it is well understood that wildfires release additional heat-trapping gases. Fires (and floods) also damage infrastructure, requiring considerable fossil-fuel derived energy to repair.

Less well understood, climate change effects increase the popularity of science-denying politicians, such as via rising insurance costs (which erode living standards) and by worsening conditions in many unfavourable settings which contribute to refugees and asylum seekers, who are often vilified in high-income countries, including by populist leaders. Such forces (too often in alliance with media) obscure scientific understanding of the underpinnings of this crisis, deepening a catastrophic spiral.

We can now say that the Australian long-term temperature trend (not just a single year) is above 1.5 degrees, joining many other national average trends – reflecting the higher rate of warming over land than ocean. Blair Trewin and I wrote about this here.
 
The IPCC Sixth Assessment Report Working Group 1 back in 2021 reported that we will experience individual years above 1.5 degrees before seeing the long-term trend reach that level roughly at the end of the decade – this is still pretty much what we expect. A few of us wrote about that then.
 
If we reach net zero, then we expect global average temperature to stabilise fairly quickly as the net result of various processes. But we know that the regional climate would still change for a long time to come, especially aspects to do with the slow processes in the oceans and ice – such as sea level rise. We are starting to explore and understand this more now, including work using Australia’s climate model ACCESS [read more here]"

The record-breaking 1.55°C rise above pre-industrial levels in 2024 exposes the catastrophic consequences of political stalling and corporate inertia. This crisis is no longer about small adjustments – the current level of warming demands a systemic transformation, particularly from industries and financial institutions driving and funding global emissions. Corporations must move from token sustainability gestures to investing in deep decarbonisation and regenerative practices. Financial systems must stop funding fossil fuels and instead prioritise green technologies and climate adaptation. Every delay in aligning business strategies with planetary boundaries not only accelerates climate collapse but also threatens global economic stability. Urgent and courageous action is no longer negotiable.

The year 2023 was so hot compared to previous years it made scientists’ heads spin. Now 2024 shows that this was no temporary spike—instead it was really the La Nina years 2021-22 that were unusually cool. We are nipping at the 1.5 Paris threshold, a few years ahead of schedule. Global warming is, if anything, speeding up as positive cloud feedbacks seem to be kicking in. It will be important to see what 2025 brings, but this is not good news.

The crossing of this threshold comes at a time when the catastrophic consequences of global heating are becoming evident throughout the word, but are nonetheless denied or downplayed by ideologues and interest groups in Australia and elsewhere. History will have a harsh judgement on those who have denied, delayed and defended against efforts to stabilise the global climate.

2024 was the warmest year on record – and quite probably the warmest year in human history. The global average land temperature was above 1.5 degrees compared to the pre-industrial baseline. Some may question why 1 or 2 degrees matter, but it is crucial to understand that small shifts in the mean temperature have outsized impacts on the behaviour of weather extremes – such as heatwaves, intense rainfall, bushfires, floods, storms and cyclones.

Unfortunately, even if we zeroed our carbon emissions tomorrow, we will now be living with the consequences of climate change on our weather for the next several decades at least. Building more resilient cities must now be at the forefront of policy decisions to make sure they remain liveable, and insurable, into the future.

It's alarming but not surprising that 2024 has been declared the warmest year on record for the globe. The new record has been caused by continued global warming combined with a small contribution from the El Niño at the start of last year. Despite the rapid rate of global warming that humanity's greenhouse gas emissions are causing and the impacts of climate change we are observing, we are still seeing global greenhouse gas emissions at record high levels. Global warming will continue until we have greatly reduced our emissions, so rapid decarbonisation is needed urgently.

The record heat of 2024 was brought about by decades of inaction on the problem of climate change. If humanity works together to reach net zero sooner rather than later then some of the worst possible impacts of climate change may be avoided.

First, we need to consider that we are behind on plans and projects that aim to keep us below the 1.5-degree target. Considering this in combination with the first single year above that long-term target suggest the drastic need for action. There is a need for projects in the face of climate change, specifically climate adaptation projects.
 
These observations can be an opportunity to raise awareness among the public, and mobilise to demand more urgent actions from the decision makers locally and globally. The aim should be to highlight the news that 2024 is the warmest year on record at about 1.55°C, and the past ten years all in the Top Ten warmest years, and direct it to initiate a momentum to address the gap in the project plans. Specifically, there is a need to use this urgency in prioritising resources for future investment and project plans and aim towards more collaborations across the political isles for transformative decisions that support the resilience of communities and their built and natural environments.

This latest annual update is a grave reminder of the urgent need for climate action - both to mitigate GHG emissions and to accelerate adaptation efforts. We are halfway through the critical decade and our efforts - local to global - must go above and beyond what we’ve seen to date to safeguard human health and well-being, and the health of the planet. The Australian political landscape must heed this as a warning that we are operating in a very different world and develop policies to match this

While we should not be surprised by this recent WMO announcement, we need to be shocked by the implications for continued global heating. Extreme temperatures cause premature loss of life, and an increased social and healthcare burden from heat-related medical episodes. They cause economic hardship to outdoor workers around the world. They cause biodiversity loss and changes to vegetation patterns. They create an increased risk of major and uncontrollable bushfires, as we’ve just seen in Los Angeles. Governments at all levels need to prioritise urgent and broad changes to both reduce greenhouse gas emissions and help the most vulnerable people to adapt to temperature rise. We have little time left to act."

A hotter globe is now unavoidable, yet we in Australia are grossly underprepared. We urgently need to begin making Australia’s cities, settlements and ecosystems far more resilient against the changing climate and increasing extreme events. 

Building resilience collectively is a matter of social justice, otherwise the rich will look after themselves and the poor will be left fend for themselves.

The World Meteorological Organization (WMO) has recently identified that 2024 was the warmest year on record. This should be no surprise as the past ten years 2015-2024 were the ten warmest years on record. This excess heat continues to underpin natural disasters (i.e. winter wildfires in California) and the catastrophic decline in natural biodiversity (for example the loss of the world’s coral reefs due to heat stress). These consequences are global. Increases in the severity of climate-induced disasters lead to global increases in insurance costs, which impacts almost every household and business in Australia. More people, in more regions are becoming exposed to heat waves, coastal storms, bushfires. These threats disproportionally impact vulnerable members of our communities who increasingly cannot afford the basics of survival, a roof over their heads that doesn’t flood, adequate heating and cooling, access to nutritious food – all the basics of living are impacted by a warming earth through sometimes convoluted pathways.

This is a seriously alarming announcement from the World Meteorological Organization. The continued burning of fossil fuels is driving the world’s climate into extremely dangerous territory. In addition to the impacts of these record-breaking temperatures on our environment and economy, our changing climate is putting our health and survival in jeopardy.

The most recent report of the Lancet Countdown highlights the record-breaking human costs of climate change (https://lancetcountdown.org/). Australians are already being hit hard, with increasing exposure to heatwaves, and catastrophes such as the 2019-20 Black Summer bushfires and the widespread and repeated flooding in 2022. The rapid transition to renewable energy is now more urgent than it has ever been – there must be no delay.

The record-breaking heat of 2024 is yet another slap upside the head for Australians and humanity to understand global heating is here. Temperature and heat do not move in a smooth line and extreme events will continue to challenge our economic, social, and political resilience. The exceptional heat and dryness driving vegetation die-off across southwestern Australia in 2024 and current fires in California are but two examples. 

Global heating puts its thumb on the scales every day, increasing the probability of nasty surprises in the form of heat, drought, fire, and flood among others. Some may be tempted to think 1.55°C isn’t much but, for example, the number of days over 40°C in Perth have more than doubled, setting conditions dangerous for human health and impacting crops, rail lines used for food shipping, and a host of other challenges we’re not ready for. The cost of inaction will be far worse than the costs of acting now.

The confirmation from the WMO that the Paris target has been breached already confirms that Earth’s atmosphere is warming faster than anticipated. And there are no political and economic indicators that this warming is slowing. Global CO2 emissions continued to increase in 2024. And lag effects of emitted CO2 reaching the atmospheric levels where it becomes climate relevant can be up to 20 years. This means we will see warming for at least the next 20, even if we achieved net zero today. We are unable to mitigate the impacts from global warming, hence we must have a laser-sharp focus on adaptation.

My research into urban cooling shows that a step change is needed to drastically improve the capacity of homes and suburbs to handle increasingly hot summer temperatures. We need to become much better in building heat-smart settlements. Buildings must withstand heat much better than what is currently approved by government organisations. Contrary to what Mr Dutton announced if elected, the National Construction Code – the lowest agreed level of quality in the construction industry – must be updated to reflect the need for improved building quality.

While the planet warms rapidly, we simply cannot afford to build houses with single glazing, dark roofs and shadeless neighbourhoods. It is absolutely irresponsible to delay adaptation to hotter summers for political gains. Scientists, not social media platforms, generate the knowledge that can help make cities cooler, reduce CO2 emissions and reverse-engineer global warming. Listen to scientists more.

The main point here is that we've officially surpassed the lower target of warming that the Paris Agreement sought to avoid - 1.55 degrees above the comparison period of 1850-1900. But it's hardly surprising. The Paris Agreement allows each country to set their baseline period and Australia, as one example, cynically chose years in which its carbon emissions were through the roof.  This plus the laughable sideshow that COP has become demonstrates we're not taking it seriously.  

As early as 2019 we showed, using a simple analysis on publicly accessible data from BOM, that Australian anomalies had already surpassed 1.5 degrees from a baseline of 1950 alone! Moreover, the global attribution study that soon followed demonstrated that fully 30% of the increase in the updated McArthur Forest Fire Index was directly due to anthropogenic climate change, converging on an increase of 1.5-1.7 degrees from 1900 to 2019, plus a massive change in the return rate of catastrophic wildfires - from every 85 years in 1900 to every eight years in 2019.  

The climate wars are over and the evidence is just piling on every year.  The real news in this new finding from the WMO is not that we've officially surpassed the limit; the news resides in what is not being said - that we've consistently failed to act as a global community for decades, and still we have laughable, frankly wicked, contempt for what the WMO secretary general, Celeste Saulo, rightly describes as 'history playing out before our eyes'.   When Australia was hit by megafires in 2019 the Trump administration tried to say that arson, and not climate change, was the main cause - this was nonsense as it would have required a 60-fold increase in arson.  

What will Trump, this world-class denialist, say now that California is being hit by the same human-induced tragedy?  We're committing arson on a global scale and the effects will be felt by our children - forever.  It's high time that real action on climate was enacted. That Raworth's donut economics, and the ideas of others like Guy Standing, are properly examined and the socioeconomic system that is destroying not just the planet but our sanity is reimagined in terms of sustainable wellbeing and human dignity.  

The frustrations of modern living, the hopelessness of our young, are intimately related to the same system that is raising global temperatures as well as driving species to extinction. They are all related. It's time to rise above the simplistic dichotomy of left versus right and rebuild an economic system that values the people and the planet. Otherwise, we're stuffed. The world is on track for 4 degrees, the sustainable development goals will predictably fail, and inequality will make of us a planetary hellscape of neo-feudal slavery.  This is a political issue and the most recent findings from WMO merely add to the mountain of evidence.

This is grim news, and comes as no surprise to climate researchers.

Accelerating heat. Unprecedented climatic extremes. Apocalyptic floods, storms fires and unrelenting droughts. This is EXACTLY what we have been warning about.

Initially, the developing countries face the full brunt and suffer major disruption to life and property, and then, the mayhem and suffering spreads to rich countries.

The two pillars of response to climate change we have long called for are firstly, mitigation, that is significantly curtailing our global emissions, and secondly, adaptation on national and local scales. Adaption involves preparing people, property and landscapes to help manage the effects of extreme climate and reduce the related harm.

Despite extraordinary efforts by some, the global collective is failing the challenge. Global carbon emissions from fossil fuels reached a record high in 2024, reaching a record 37.4bn tonnes of CO2, 2% above 2023 emissions.

By and large, governments, industries and individuals are not trying hard enough.  Australians are travelling at record levels, with outbound and inbound air travel experiencing unprecedented growth in 2024. Most of this is discretionary travel, holidays.

The reality of the immense threats posed by unmitigated climate change is clearly still not sinking in.

Continued failure to prevent, prepare for, and protect against, even more extreme weather-related events is a recipe for tragedies. Los Angeles is in the grip of a blame game. A more productive response is for us ALL to look at our own lives, our own emissions, our own efforts to help communities and our own voting patterns. We must all work harder.

2024 was a year of extremes but was not an isolated occurrence. It is part of a worsening trend of more intense floods, prolonged droughts, and record-breaking extremes.

We found rainfall records are being broken with increasing regularity. For example, record-high monthly rainfall totals were achieved 27 per cent more frequently in 2024 than at the start of this century, whereas daily rainfall records were achieved 52 per cent more frequently. Record-lows were 38 per cent more frequent, so we are seeing worse extremes on both sides.

We need to prepare and adapt to inevitably more severe extreme events. That can mean stronger flood defences, developing more drought-resilient food production and water supplies, and better early warning systems.

Water is our most critical resource, and its extremes—both floods and droughts—are among the greatest threats we face.

The global temperature varies year to year, but it is very clear that there is a increasing trend. Next year might not reach 1.55 degrees of warming, but it is evident that in the coming decades 1.55 degrees warmer will be considered a cool year.

Temperature variations mean that globally we have hit 1.5 degrees of warming in 2024 but this this not the mean warming across recent years. Australia however is warming faster than the global average and our mean warming has reached 1.5 degrees, so we are seeing years above and below this level.

Australia has had its second hottest year on record in 2024.

Hot summers are not a surprise to Australians. Heatwaves and bushfire risk have become part of our summer life. For those not used to the heat, we need to be conscious of hydrating and making sure our vulnerable people have adequate air conditioning. 

Marine heatwaves are a growing concern for Australians. Our coral reefs continue to struggle and our ecosystems and fisheries are struggling to adapt to new environments and unprecedented pressures.

The effects of climate change are not always obvious in our forward planning. Australians have a lot to consider in the warmer world we have now and the increased warming to come. What does this mean for our sporting activities, concerts, public transport, and our ability to generate energy to meet growing demands? We are already seeing increases in insurance premiums in the wake of flooding and intense rainfall – these phenomena will continue and amplify over coming decades. Can we continue to remain a resilient Australia with more bushfire risk, heatwaves and intense rainfall happening with greater frequency and closer together?