The IPCC’s most optimistic scenario describes a world in which global CO2 emissions are reduced to zero by 2050. This is the only scenario that achieves the Paris Agreement goal of holding global warming to about 1.5 degrees Celsius above pre-industrial temperatures.

Societies shift to more sustainable practices, with a shift in focus from economic growth to overall well-being. Investment in education and health increases.

Inequality decreases. Extreme weather events occur more frequently, but the world is spared the worst effects of climate change.

Scenario 5 (the last) is a future to avoid at all costs. Current CO2 emissions levels roughly double by 2050. The global economy grows quickly, but this growth is fuelled by exploiting fossil fuels and energy-intensive lifestyles. By 2100, the average global temperature is a scorching 4.4 degree Celsius higher.