Three years left to limit warming to 1.5C, top scientists warn
The Earth could be doomed to breach the symbolic 1.5C warming limit in as little as three years at current levels of carbon dioxide emissions.That's the stark warning from more than 60 of the world's leading climate scientists in the most up-to-date assessment of the state of global warming.Nearly 200 countries agreed to try to limit global temperature rises to 1.5C above levels of the late 1800s in a landmark agreement in 2015, with the aim of avoiding some of the worst impacts of climate change.But countries have continued to burn record amounts of coal, oil and gas and chop down carbon-rich forests - leaving that international goal in peril.
"Things are all moving in the wrong direction," said lead author Prof Piers Forster, director of the Priestley Centre for Climate Futures at the University of Leeds."We're seeing some unprecedented changes and we're also seeing the heating of the Earth and sea-level rise accelerating as well."These changes "have been predicted for some time and we can directly place them back to the very high level of emissions", he added.At the beginning of 2020, scientists estimated that humanity could only emit 500 billion more tonnes of carbon dioxide (CO2) - the most important planet-warming gas - for a 50% chance of keeping warming to 1.5C.But by the start of 2025 this so-called "carbon budget" had shrunk to 130 billion tonnes, according to the new study.That reduction is largely due to continued record emissions of CO2 and other planet-warming greenhouse gases like methane, but also improvements in the scientific estimates.If global CO2 emissions stay at their current highs of about 40 billion tonnes a year, 130 billion tonnes gives the world roughly three years until that carbon budget is exhausted.This could commit the world to breaching the target set by the Paris agreement, the researchers say, though the planet would probably not pass 1.5C of human-caused warming until a few years later.
Last year was the first on record when global average air temperatures were more than 1.5C above those of the late 1800s.A single 12-month period isn't considered a breach of the Paris agreement, however, with the record heat of 2024 given an extra boost by natural weather patterns.But human-caused warming was by far the main reason for last year's high temperatures, reaching 1.36C above pre-industrial levels, the researchers estimate.This current rate of warming is about 0.27C per decade – much faster than anything in the geological record.And if emissions stay high, the planet is on track to reach 1.5C of warming on that metric around the year 2030.After this point, long-term warming could, in theory, be brought back down by sucking large quantities of CO2 back out of the atmosphere.But the authors urge caution on relying on these ambitious technologies serving as a get-out-of-jail card."For larger exceedance [of 1.5C], it becomes less likely that removals [of CO2] will perfectly reverse the warming caused by today's emissions," warned Joeri Rogelj, professor of climate science and policy at Imperial College London.
'Every fraction of warming' matters
The study is filled with striking statistics highlighting the magnitude of the climate change that has already happened.Perhaps the most notable is the rate at which extra heat is accumulating in the Earth's climate system, known as "Earth's energy imbalance" in scientific jargon.Over the past decade or so, this rate of heating has been more than double that of the 1970s and 1980s and an estimated 25% higher than the late 2000s and 2010s."That's a really large number, a very worrying number" over such a short period, said Dr Matthew Palmer of the UK Met Office, and associate professor at the University of Bristol.The recent uptick is fundamentally due to greenhouse gas emissions, but a reduction in the cooling effect from small particles called aerosols has also played a role.This extra energy has to go somewhere. Some goes into warming the land, raising air temperatures, and melting the world's ice.But about 90% of the excess heat is taken up by the oceans. That not only means disruption to marine life but also higher sea levels: warmer ocean waters take up more space, in addition to the extra water that melting glaciers are adding to our seas.The rate of global sea-level rise has doubled since the 1990s, raising the risks of flooding for millions of people living in coastal areas worldwide.
While this all paints a bleak picture, the authors note that the rate of emissions increases appears to be slowing as clean technologies are rolled out.They argue that "rapid and stringent" emissions cuts are more important than ever.The Paris target is based on very strong scientific evidence that the impacts of climate change would be far greater at 2C of warming than at 1.5C.That has often been oversimplified as meaning below 1.5C of warming is "safe" and above 1.5C "dangerous".In reality, every extra bit of warming increases the severity of many weather extremes, ice melt and sea-level rise."Reductions in emissions over the next decade can critically change the rate of warming," said Prof Rogelj."Every fraction of warming that we can avoid will result in less harm and less suffering of particularly poor and vulnerable populations and less challenges for our societies to live the lives that we desire," he added.
Sign up for our Future Earth newsletter to keep up with the latest climate and environment stories with the BBC's Justin Rowlatt. Outside the UK? Sign up to our international newsletter here.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
The Independent
6 hours ago
- The Independent
Revealed: The AI chatbot requests that cause the most carbon emissions
A new study reveals that every query to large language models like ChatGPT consumes energy and generates carbon emissions. Complex reasoning questions, such as those in abstract algebra or philosophy, lead to significantly higher carbon emissions, up to six times more than simpler queries. Models designed for explicit reasoning processes produce substantially more carbon dioxide, with some generating up to 50 times more emissions than concise response models. The study highlights an "accuracy-sustainability trade-off," where highly accurate AI models often result in greater energy consumption and carbon footprint. Researchers recommend that users reduce emissions by prompting AI for concise answers and reserving high-capacity models for tasks that genuinely require their advanced capabilities.
Daily Mail
7 hours ago
- Daily Mail
HMP Mars: Living on the Red Planet will be like life in PRISON, expert warns
When humans finally settle on Mars, they will be stepping out into one of the most hostile environments in the solar system. But if we want to understand what life will really be like on the Red Planet, we should look to a hostile environment much closer to home. Life for astronauts in a Martian colony will be extremely similar to the conditions inside today's prisons, according to a leading space scientist. From isolation and a lack of personal space to bad food and a rigid routine, astronauts' conditions will be much closer to those of prisoners than explorers. Space agencies have spent decades studying extreme environments like Antarctic research bases to learn how humans might react to living in space. However, Professor Lucy Berthoud, a space systems engineer at the University of Bristol, says that prisons are already the closest parallel to life on Mars. Professor Berthoud told MailOnline that prisoners and astronauts both face: 'Too little personal space and privacy, overcrowding, poor food, unnecessary risks, rigid regimes with no autonomy, little variation in daily activities.' With astronauts trapped 140 million miles from home (225 million km), Professor Berthoud warns they may feel even more isolated than those locked in cells here on Earth. The biggest difference between astronauts and prisoners is obviously that one voluntarily takes a highly sought-after position, while the other has their freedom removed as a punishment. However, once the astronauts actually make it to a Martian colony, their conditions would be remarkably similar. Most obviously, both prisoners and astronauts will be physically trapped inside a cramped, dangerous environment with the same small set of people. In prisons, the European standard for a cell is four metres square per person, but overcrowding means that there is often much less space. On a Martian colony where resources are scarce and survival is the primary goal, astronauts are likely to face similarly cramped quarters. For example, NASA's Apollo Command and Service module, which took astronauts into lunar orbit, had just 6.2 cubic metres of space for three astronauts. This lack of privacy, combined with close proximity to other people, can lead to heightened stress and a much greater risk of conflict. Those tensions are only made worse by the fact that both prisons and Mars are extremely dangerous environments. While the sources of danger are extremely different, this persistent level of threat has the same effect on someone's psychology. Professor Berthoud says: 'Living in a high-risk environment would mean that your threat situation would be constantly switched on, which takes a toll on you psychologically and physically over the long term. 'Astronauts are specially selected to be good at dealing with emergency situations, unlike prisoners, but over the mission length this would still have an effect.' In addition to their living conditions, astronauts and prisoners may find themselves with similar lifestyles. In prisons, those incarcerated have their schedule planned out down to the minute with restrictions on everything from eating and sleeping to working and resting. This is exactly the same situation faced by the astronauts currently living on the International Space Station (ISS). Astronauts on the ISS h ave 15-hour working days with two hours of compulsory exercise, eight hours of work, and only a single hour of personal time. Professor Berthoud points out that this lack of control can lead astronauts to rail against or even disobey NASA's rigid mission guidelines. NASA's astronauts are subject to a gruelling daily schedule with just a single hour of personal time per day Likewise, for both prisoners and astronauts, one of the biggest issues is the availability of fresh, tasty, nutritious food. The UK government standard for prisoners' meals is set at £2.70 per person per day, which means that food is often of low nutritional value and famously unpleasant. While astronauts on Mars are likely to have much more expensive and pleasant food than prisoners, a lack of variety and fresh ingredients will still be a major restriction. On the ISS, NASA has invested huge resources into trying to make space food palatable. However, astronauts losing their appetite and failing to keep their weight up is a constant concern. However, the most important similarity is that both prisoners and astronauts on Mars would face heightened levels of isolation. Prisoners, just like astronauts on a remote planet, are taken away from society and have their contact with friends, family, and the outside world cut to a minimum. Even though astronauts willingly subject themselves to this isolation, they still face the same effects. Professor Berthoud says: 'I feel that the effects of isolation will be similar, but for Mars there will be the added factor of feeling very remote from everyone you care about and love. 'The fastest you could get home would be 6 months, so that would add to the isolation.' Although Professor Berthoud says that life on Mars could be similar to a prison, this doesn't mean NASA should model its Mars colonies after the prison environment. Mars bases should be equipped with measures to maximise privacy and autonomy, while astronauts should be given meaningful activities to help combat monotony. Ultimately, fixing these problems on Mars might even help us make prisons more habitable back here on Earth. Professor Berthoud says: 'I would suggest we would want to rethink prisons to be more like the ideal space base! 'I would imagine that more space, more autonomy, more personalisation, more sense of purpose would help anyone deal better with a stressful situation, even if they are there to keep society safe.' Mars has two miles of WATER buried at its equator - and scientists say it could support the first settlers on the Red Planet Despite once being home to lush oceans of liquid water billions of years ago, any traces of H2O on Mars today are well hidden. But experts say there's two miles of water buried beneath the surface in an area of the planet's equator, known as the Medusae Fossae Formation (MFF). The water is frozen as ice in a layer measuring over two miles (3.7km) thick, according to new data from the Mars Express spacecraft. If melted, the water would cover the whole of Mars in a layer of liquid up to 8.8 feet (2.7 metres) deep, and would be enough to fill Earth's Red Sea.
The Independent
9 hours ago
- The Independent
Climate change blamed for UK heatwave amid 32C temperatures
Searing temperatures of 32C hitting the UK this week have been made 100 times more likely due to human-caused climate change, scientists have warned. A rapid study by the World Weather Attribution (WWA) research group found the current heatwave in the south-east of England was around 10 times more likely than without human activity warming the planet. Dr Fredi Otto, from Imperial College London, underscored the severity, warning that heatwaves are "silent killers" and that the impacts of heat are "severely underestimated", leaving the UK unprepared for the conditions expected to persist into the weekend. Experts highlighted that older people, along with those suffering from heart issues, respiratory illnesses, and conditions such as diabetes, face the highest risk of death. They also noted that heatwaves occurring earlier in the summer are particularly deadly, as the population is less acclimatised to coping with warmer conditions. The researchers also identified wildfires as an "emerging risk" for the UK during summer, with conditions increasingly resembling those found in southern Europe. They urged the public to exercise extreme caution with barbecues, cigarettes, and glass, all of which can ignite fires in the hot, dry weather. This study marks only the second time the WWA, known for its rapid assessments of climate change's role in specific extreme weather events, has analysed a forecasted event rather than one that has already occurred. The analysis, which drew on observations for early summer heat in the south east of the UK, found that a heatwave – defined as three days of temperatures above 28C for the region – in June would be expected once every five years today. But without humans warming the atmosphere by around 1.3C since pre-industrial times, such a heatwave would only have occurred about once every 50 years, the study shows. The heatwave was made approximately 2-4C more intense as a result of the overall warming of the planet, meaning the current weather 'just wouldn't have been a heatwave without human-induced warming', Dr Ben Clarke, from Imperial College London, said. Temperatures had been forecast to hit 32C across the south east on Saturday and had already reached that level on Thursday in London. Heat of that level could be expected in June once in 25 years in the current climate, but only once in 2,500 years in June before industrialisation, the researchers said. While the impacts of temperatures rising above 30C are not as severe as the record-breaking heat topping 40C in some places in July 2022, the researchers warned people were still at risk. They urged people to ensure they were drinking enough water, and to encourage elderly relatives to do the same, avoid areas with high air pollution, keep windows and curtains shut during the day, and consider going to cooler public buildings such as museums to protect against the heat. Dr Clarke, researcher at the Centre for Environmental Policy at Imperial College London, said: 'This heatwave is another reminder that our planet has already heated to a dangerous level. 'We're at 1.3C today, but heading for around 3C this century. 'With every fraction of a degree of warming, the UK will experience hotter, more dangerous heatwaves. 'That means more heat deaths, more pressure on the NHS, more transport disruptions, tougher work conditions and poorer air quality.' Dr Otto, associate professor in climate science at the Centre for Environmental Policy, said: 'We know exactly what has intensified this heatwave – burning oil, gas and coal, which has loaded the atmosphere with planet-heating greenhouse gases. 'It is totally insane we have political leaders in the UK trying to drag us back to the past with calls for more fossil fuels. 'The climate will continue to drive increasingly dangerous heatwaves, fires and floods in the UK until emissions are reduced to net zero globally.' She added that while people working in air-conditioned offices would 'probably be OK' this week, poorer people working outdoors, in kitchens or other hot environments and then returning home to poorly insulated flats would be enduring hot conditions throughout. 'Making our societies more equal is essential to reduce the impacts of climate change,' Dr Otto said.
