Professor Steffen said scientists considered 10 natural feedback processes as part of the study, some of which were "tipping elements" that could lead to abrupt changes if a critical threshold was crossed.
Sea levels could also rise between 10 and 60 metres, threatening coastal areas. This summer dozens of people have died in wildfires and heat waves from the U.S. to Asia, giving the world an insight into what could lie ahead. At this point, the global temperatures are already one degree higher than pre-industrial times.
The planet at risk of entering an irreversible "hothouse" climate, scientists say.
Currently, global average temperatures are just over 1 degree Celsius above pre-industrial and rising at 0.17 degree Celsius per decade.
If the tipping points described in the report kick in, Mr Curtain said, we could enter what is described as runaway warming.
"The implications are that if we can't stop it we're in a hell of a mess".
The scientists warning comes as the Met Office said Britain's heatwave could continue for several months, with higher than average temperatures likely until October. "It would simply be unbearable for our society".
The study says that mitigating that risk would require collective global action, including a drastic transformation of "social values" and the pursuit of new technology.
More than 200 countries pledged to take action on climate change under the Paris Accord struck in 2015.
The scientific community, by and large, is in agreement that global temperatures will exceed 2C above pre-industrial levels within this century, possibly within the next few decades. However, there are no binding targets, and the USA later pulled out, dealing a blow to global efforts to form a united front against climate change.
Such processes include permafrost thaw; the loss of methane hydrates from the ocean floor; weaker land and ocean carbon sinks; the loss of Arctic summer sea ice and the reduction of Antarctic sea ice and polar ice sheets, said the report.
As Rockström explains, the "tipping elements" examined in the research "can potentially act like a row of dominoes".
"Once one is pushed over, it pushes Earth towards another".
Rockström added that stopping the "whole row of dominoes from tumbling over" will be either hard, or impossible, and that "if Hothouse Earth becomes the reality", some places on Earth will be uninhabitable.
With Arctic ice and glaciers melting away; increasingly powerful and frequent storms in the Atlantic and Pacific; coral reefs dying from warming oceans; record-setting wildfires in the US; unprecedented heatwaves in Europe, the Middle East, and elsewhere-climate researchers have been at the forefront of sounding the alarms about the frightening path humanity is now following.
"What this is all about is humanity is recognizing the fact that we need to manage our resources at a global level... We totally hand over our fate to an Earth system that starts rolling out of equilibrium".
Speaking about the impact of climate change, Chris Rapley, Professor of Climate Science at University College London said: "Previous research has shown that an increase in the mean global temperature of 11-12C would make more than half of the land area now occupied by humans uninhabitable".