The latest research shows that the global warming process has been accelerating significantly since about 2015. In the past decade, the rate of warming of the earth has been almost twice that of previous decades, making the prospect of maintaining the 1.5 degrees Celsius temperature control target of the Paris Agreement within this century even more worrying. This analysis, led by the Potsdam Institute for Climate Impact Research (PIK) in Germany, after excluding a variety of known natural climate fluctuation factors, confirmed for the first time with statistical significance that the global warming rate has significantly "accelerated".
The research team pointed out that in the past decade, the global average temperature has increased at a rate of about 0.35 degrees Celsius per decade, and the specific value varies slightly depending on the data set used. By comparison, the average rate of global warming over the long period from 1970 to 2015 was just under 0.2 degrees Celsius per decade. The paper states that the warming slope in the latest decade is the fastest warming phase observed since instrumental records began in 1880.
Grant Foster, co-author of the paper and an American statistics expert, said: "We can now confirm that since about 2015, there have been significant and statistically highly significant signs of acceleration in global warming." He explained that by filtering out known natural influencing factors in the observational data, the study greatly weakened the short-term "noise", making the long-term warming signal more clearly visible.
In the real climate system, short-term natural factors such as El Niño events, volcanic eruptions, and solar activity cycles will push up or down global temperatures on a time scale of several years, masking the long-term warming trend behind them. In order to weaken these interferences, the research team selected five sets of temperature data sets that are widely used around the world, and adjusted the natural fluctuations related to El Niño, volcanic activity, solar cycles, etc., in order to better "extract" the long-term warming signal driven by human activities.
Stefan Ramstorff, a scientist at the Potsdam Institute and the first author of the paper, said that the adjusted data show that global warming has accelerated significantly since 2015, with a statistical confidence level of more than 98%. This result has been consistently verified in all data sets examined, regardless of the analysis method used.
The focus of this study is to clarify whether the "speed" of warming has changed, rather than directly defining the specific causes behind this change. When researchers deduct the effects of the El Niño effect and the recent solar activity maximum from the temperature series, the unusually hot years 2023 and 2024 will "cool" slightly in a statistical sense. However, in all data sets, these two years still rank among the top two "warmest years" in modern temperature records. The study pointed out that starting from about 2013 or 2014, the trend of accelerated warming has gradually emerged.
To determine whether the rate of global warming has changed since the 1970s, the team used two complementary statistical techniques: one is to fit a quadratic function trend to capture the overall curvature of the warming curve; the other is to build a piecewise linear model to identify the specific time of the "inflection point" in the long-term warming rate.
The study did not attempt to completely clarify all the driving mechanisms of accelerated warming in a single paper, but the authors pointed out that existing climate models have previously predicted that as greenhouse gas concentrations continue to rise, the global warming rate will increase at a certain stage, which is in line with the theoretical expectations of mainstream climate science.
"If the warming rate of the past decade continues, then on a long-term scale, global warming exceeding the 1.5 degrees Celsius limit set by the Paris Agreement may occur before 2030," Ramstorff warned. He emphasized that the specific rate of future warming of the earth still fundamentally depends on how quickly and to what extent humans reduce carbon dioxide emissions from fossil fuel burning to zero.
According to reports, this research paper titled "Significant Acceleration of Global Warming" has been published in the international academic journal "Geophysical Research Letters", further providing the latest scientific assessment basis for global climate governance.