A new study shows that the most ambitious goal of the Paris climate agreement — to limit the average global temperature increase to 1.5°C above pre-industrial levels — is scientifically possible if the world acts now. Published in the journal Nature Geoscience, the analysis is based on modeling data from the IPCC Fifth Assessment Report and states that the 1.5°C aim is "not yet a geophysical impossibility", on the proviso that countries meet more ambitious emission reductions than previously pledged. The authors of the international study suggest that if we can limit the amount of greenhouse gas emissions to around 880 billion tonnes of carbon dioxide — what we'd normally emit in about 20 years — starting from 2015 onwards (so the clock has already started ticking), then it may be possible to keep the rise in temperatures to less than 1.5°C above pre-industrial levels by the end of the century. To find out more check out Emission budgets and pathways consistent with limiting warming to 1.5 °C.