Science worst-case scenario is reality right now

Climate science’s worst-case scenario isn’t just an awful warning. It describes what is already happening right now. A report from the US Proceedings of the National Academy of Sciences took a closer look at the evidence for climate change in terms of carbon dioxide emissions and climate models, and at cumulative greenhouse gas emissions since 2005. By 2020, the emissions matched the “business as usual” predictions very closely. The study then extended the trends to 2030, and to 2050, with the same outcome. This means that by the end of the century the planet could be 3.3°C to 5.4°C warmer than it was at the start of the Industrial Revolution and the worldwide switch to fossil fuels. The worst-case scenario should remain on the table as a useful risk assessment tool the study concludes.

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