Major climate changes inevitable and irreversible – IPCC’s starkest warning yet

Report warns temperatures likely to rise by more than 1.5C bringing widespread extreme weather

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Human activity is changing the Earth's climate in ways unprecedented" in thousands or hundreds of thousands of years, with some of the changes now inevitable and irreversible", climate scientists have warned.

Within the next two decades, temperatures are likely to rise by more than 1.5C above pre-industrial levels, breaching the ambition of the 2015 Paris climate agreement, and bringing widespread devastation and extreme weather.