The expected turnaround in carbon dioxide (CO₂) emissions has not materialized: a report for 2025 assumes that global greenhouse gas emissions will continue to increase, perhaps by 1.1 percent compared to the previous year. If emissions continue at this rate, the remaining CO₂ budget to meet the 1.5 degree target set in the Paris Agreement will run out before 2030. A large international research group led by Pierre Friedlingstein of the University of Exeter presented their report Global Carbon Budget 2025 in the journal “Earth System Science Data”.
Therefore, global CO₂ emissions will increase to 38.1 billion tonnes this year. In 2024 it will reach 37.8 billion tonnes. There was growth for all fossil fuels: coal (+0.8 percent), petroleum (+1.0 percent) and natural gas (+1.3 percent). Therefore, emissions in America are expected to increase by 1.9 percent compared to the previous year, in India by 1.4 percent, and in China and the European Union by 0.4 percent each.
“Given the continued rise in CO₂ emissions, it is no longer realistic to keep global warming below 1.5 degrees Celsius,” Friedlingstein was quoted as saying in a statement from his university. He and his team of about 100 research institutions have collected extensive data and used it to calculate global developments in computer models.
This report also shows encouraging trends
Therefore, CO₂ concentrations in the atmosphere are likely to increase to 425.7 ppm (parts per Million). In 2024 it reaches a record level of 423.9 ppm, as announced by the World Weather Organization (WMO) a month ago.
However, the researchers also saw positive trends that prove, for example, that climate protection is not weakening the economy: “35 countries were able to reduce their emissions while maintaining economic growth,” said co-author Corinne Le Quéré of the British University of East Anglia in Norwich, looking at the period from 2015 to 2024. The number of countries was twice as many as ten years earlier.
These countries include many European countries, but also Australia, Israel, New Zealand, South Korea and Taiwan. However, Le Quéré stressed that this progress is not large enough to sustainably reduce global emissions given rising energy demand.
Forest deforestation has been reduced significantly
Another positive trend is that land use changes, especially deforestation, have been greatly reduced through environmental policy measures, the report notes. “Deforestation rates in the Amazon region have decreased and reached their lowest level since 2014 this season,” said Julia Pongratz of the Ludwig Maximilian University of Munich, one of the report’s authors. However, devastating fires in 2024 have shown how sensitive ecosystems will be if global warming is not curbed, Pongratz warned.
On the other hand, an unfavorable trend is impacting environmental systems that previously absorbed large amounts of CO₂ from the atmosphere, the so-called sinking of oceans and land: their absorption capacity is decreasing, mainly due to the impacts of climate change. According to scientists’ calculations, the increase in CO₂ in the atmosphere by 8 percent since 1960 is due to the fact that land and oceans are increasingly unable to absorb CO₂. In the period 2015 to 2024, the absorption capacity of ecosystems on land decreased by 25 percent and the absorption capacity of ecosystems in the ocean by 7.9 percent.
