A major international climate study has found that Earth is heating at an accelerating pace with human caused global warming reaching 1.37°C above pre industrial levels in 2025. Scientists warn that if current trends continue, the world could exceed the critical 1.5°C warming threshold in just four years.
The findings come from the latest Indicators of Global Climate Change (IGCC) report, published in the journal Earth System Science Data. More than 70 climate scientists from 56 institutions across 17 countries contributed to the assessment.
Researchers say the most worrying signal is the growing imbalance in Earth energy system. This indicator measures how much extra heat the planet is absorbing compared to how much it releases back into space.
According to the report Earth energy imbalance has reached a record high and has doubled in recent decades, showing that heat is accumulating faster than ever across the atmosphere, oceans, land and ice sheets.
Professor Piers Forster, Director of the Priestley Centre for Climate Futures at the University of Leeds and lead author of the study, said the growing energy imbalance is one of the clearest signs that climate change is accelerating.
“Without human influence, Earth energy balance should be close to zero. Instead, heat is building up rapidly across the climate system,” he explained.
The report also found that global greenhouse gas emissions reached an all-time high of 56.8 billion tonnes of carbon dioxide equivalent in 2024. Most of these emissions continue to come from the burning of fossil fuels such as coal, oil, and natural gas.
Scientists estimate that human driven warming is now increasing at a rate of approximately 0.27°C per decade, the highest level ever recorded.
While carbon dioxide remains the largest contributor to climate change, researchers noted that declining sulfur dioxide emissions are also playing a role. Sulfur pollution previously reflected some sunlight back into space, partially masking greenhouse gas warming. As air quality improves and sulfur pollution decreases, more of the underlying warming is becoming visible.
Dr. Samantha Burgess, Strategic Lead for Climate at the Copernicus Climate Change Service, said nearly all of the warming observed during the past decade can be directly linked to human activities.
“The impacts on ecosystems, economies, and livelihoods are already being felt around the world and will continue to intensify as temperatures rise,” she said.
The report highlights growing changes across every part of the climate system. Oceans are warming glaciers and ice sheets are melting, permafrost is thawing and sea levels are rising at increasing rates.
Scientists reported that global sea levels have risen by approximately 23 centimetres since 1901. The current rate of rise is around 1.8 millimetres per year and continues to accelerate.
Although these figures may seem small researchers warn that even modest increases in sea level significantly increase coastal flooding risks, particularly in low lying regions.
Another major concern is the rise in marine heatwaves. For the first time the IGCC report included an indicator tracking the number of marine heatwave days worldwide.
The study found that 2025 experienced 65 marine heatwave days globally, while the number of marine heatwave days has more than tripled since 1991.
Professor June-Yi Lee of Pusan National University said marine heatwaves are becoming increasingly common as ocean temperatures continue to rise.
These events damage marine ecosystems threaten fisheries, disrupt food production, affect coastal protection systems, and can even influence extreme weather patterns on land.
Perhaps the most alarming finding involves the remaining carbon budget the amount of carbon dioxide humanity can still emit while keeping global warming below 1.5°C.
Scientists estimate that only 130 billion tonnes of carbon dioxide remain in the global carbon budget as of the beginning of 2026. At current emission levels, that budget could be exhausted within approximately three years.
The report warns that despite improvements in renewable energy and climate policies, greenhouse gas emissions remain far too high to prevent dangerous levels of warming.
Researchers are calling for rapid and large scale reductions in fossil fuel use, stronger climate action, and continued investment in climate monitoring systems.
Dr. Chris Smith from the International Institute for Applied Systems Analysis stressed that many of the global climate datasets used in the report face funding uncertainties.
“We need international cooperation to maintain climate observations and monitoring systems. Without them, understanding future climate changes and making informed decisions will become much more difficult,” he said.
The findings underline a growing scientific consensus: climate change is no longer a future threat but a present reality. As temperatures continue to rise and heat accumulates throughout the Earth system, scientists say the coming decade will be critical in determining whether the world can avoid even more severe climate impacts.