A major new study has been published - one that gives much more certainty on the extent of future warming we might expect.
Along with many other international climate scientists, it was led by my colleague, climate scientist Steven Sherwood from the University of New South Wales in Australia. So, I asked him a few questions about it, to drill down what this means for us and the future.
We know Earth's climate warms as greenhouse gas concentrations like carbon dioxide rise in the atmosphere. From the 1950s, NASA temperature data show Earth has warmed ~0.8 °C up until the latest decade.The scale of future warming remains uncertain for a variety of reasons, the biggest unknown being how much carbon pollution humanity will emit over the coming decades. That is based on political and economic systems - hardly something we can predict over the coming months - let alone the coming decades!
So, scientists have developed complex earth-system models to predict the future using a variety of future carbon pollution scenarios - ranging from the 'burn all the coal reserves' option to the 'shut down all coal-fired power plants tomorrow' option.
But another important element of uncertainty is how sensitive Earth's climate is to carbon dioxide.