2025 at4 is a term used to describe the fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC), which was released in 2007. The report assesses the scientific, technical, and socio-economic information relevant to understanding the climate system and climate change. It provides a comprehensive assessment of the state of knowledge on climate change, including its causes, impacts, and potential future developments.
The AR4 concluded that it is extremely likely that human activities are the dominant cause of observed warming since the mid-20th century. The report also projected that global average temperatures will continue to rise over the next century, with the rate of warming likely to be greater than in the past 50 years. The report warned that the impacts of climate change will be widespread and severe, including rising sea levels, more extreme weather events, and changes in plant and animal life.
