The climate crisis is reaching an unprecedented level of urgency as global temperatures soar to record-breaking heights, with July 2023 marking another alarming milestone. 

Based on the China global Merged Surface Temperature dataset 2.0 (CMST 2.0), a new study led by Prof. LI Qingxiang from Sun Yat-sen University has revealed that 2023 is expected to be the hottest year ever. LI is also a research fellow at the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences. 

The findings were published in Advances in Atmospheric Sciences on Sept. 19. 

The researchers analyzed the CMST 2.0 dataset and discovered that 2023 has already experienced the third hottest first half-year since records began, narrowly trailing 2016—the warmest year—and 2020—the second warmest. The global mean sea surface temperatures (SSTs) surged to an all-time high in April, while global mean land air temperatures followed suit by reaching their second-highest monthly level in June. This combination resulted in May being crowned the hottest month ever recorded for global mean surface temperatures. 

Global temperatures will continue to rise into the second half of 2023, driven by factors including El Niño and widespread wildfires. Both global mean SSTs and global mean land temperatures reached unprecedented highs for July, shattering previous records.

"Given the current trajectory and short-term forecast results of El Niño, along with the extremely positive phase of the Atlantic Multidecadal Oscillation that strongly influences global surface temperatures, 2023 is expected to be the hottest year on record," said Prof. LI. "Moreover, 2024 may witness even higher global surface temperatures."

The CMST 2.0 dataset, developed by Prof. LI's team, is one of the most comprehensive global surface temperature benchmark datasets to date. It takes into account the accuracy of both global and regional climate change, raising the level of global temperature monitoring to a new level. The dataset integrates over a century’s worth of global land air temperature data and state-of-the-art research results from across the globe, resulting in an invaluable resource for climate scientists and policymakers. Based on this dataset, the team was the first to point out that the much-talked-about "global warming hiatus" during the last decade was just a statistical artifact, and in 2022, the dataset was expanded to include Arctic temperature data, further enhancing its global coverage. 

Accessible to both the scientific community and general public, the CMST 2.0 dataset is freely available on the Global Climate Change Observation and Modeling Data Platform at http://www.gwpu.net/en/. 

As global warming accelerates, the likelihood of extreme weather events and disasters increases. Therefore, immediate and sustained efforts are needed to mitigate the devastating impacts of climate change.