The world could use up its remaining carbon budget for limiting global warming to 1.5 degrees Celsius in as little as three years if emissions remain at current levels, according to a new warning by more than 60 top climate scientists.

The study, the most current assessment of the planet's heating, says carbon dioxide emissions continue to rise sharply despite global pledges, pushing the 2015 Paris Agreement goal further out of reach.

According to the study, the amount of carbon dioxide the world can emit while still having a 50 percent chance of limiting warming to 1.5C dropped from 500 billion tonnes in 2020 to just 130 billion tonnes by early 2025.

With global CO2 emissions hovering around 40 billion tonnes a year, scientists say the world could cross that line within three years.

“Things are all moving in the wrong direction,” said lead author Prof Piers Forster of the Priestley Centre for Climate Futures. “We're seeing some unprecedented changes and we're also seeing the heating of the Earth and sea-level rise accelerating as well.”

The continued burning of coal, oil, and gas, along with large-scale deforestation, has driven the sharp rise in greenhouse gases. While last year was the first time global average temperatures exceeded 1.5C above pre-industrial levels for a full year, researchers say human activity remains the main driver of this trend.

“This has been predicted for some time and we can directly place it back to the very high level of emissions,” said Forster.

Though a single year's spike does not count as a breach of the Paris target, the current warming pace—about 0.27C per decade—is faster than anything seen in the Earth's geological history. At this rate, the world could reach 1.5C warming permanently by around 2030.

Prof Joeri Rogelj of Imperial College London warned that relying on future carbon removal technologies is risky. “For larger exceedance, it becomes less likely that removals will perfectly reverse the warming caused by today's emissions,” he said.

The report also reveals that the rate of heat buildup in the Earth's system has more than doubled compared to the 1970s and 1980s, and increased 25 percent since the late 2000s.

Most of this excess energy is absorbed by oceans, leading to marine disruption and rising sea levels. The speed of sea-level rise has doubled since the 1990s, threatening coastal populations globally.

Dr Matthew Palmer of the UK Met Office called the rapid heating “a really large number, a very worrying number” given the short timeframe.

Despite the grim outlook, the scientists noted a slight slowing in the rise of emissions, partly due to the adoption of cleaner technologies. Still, they stress that only “rapid and stringent” emissions cuts can prevent more severe damage.

The authors caution against framing 1.5C as a strict safety line. “Every fraction of warming that we can avoid will result in less harm and less suffering,” said Rogelj, adding that lower warming levels will reduce the burden on societies, especially the poor and vulnerable.