According to the Global Tipping Points Report, put together by more than 200 researchers worldwide, at the current level of warming, the Earth risks triggering at least five tipping points and posing exceptional threats to humanity.
The five cited tipping points are: the collapse of the Greenland ice sheet; the collapse of the West Antarctic ice sheet; the mass die-off of warm water coral reefs; the thawing of Arctic permafrost; and the slowing of North Atlantic subpolar gyre circulation. The report suggests that the die-off of coral reefs is likely at current temperatures while the other tipping points are "possible."
The world is currently on a disastrous trajectory. Tipping-point risks threaten to trigger fundamental, abrupt, and irreversible changes to our planet as well as cause dire and horrific effects on human lives. The Global Tipping Points Report is a clear warning to world leaders that the global community must take bold, coordinated policies across multiple sectors—including the phase-out of fossil fuels and land-use emissions by 2050—to tip the odds in favor of billions of people.
The Global Tipping Points Report has yet to clarify how close we are to crossing the tipping points and what the exact impacts would be if we did. Science can't predict everything precisely because the dynamics and outcomes of natural and social systems arise from the interplay of many factors and choices. As the worst uncertainties about climate change are outside the scope of climate models, such warnings must be taken with a grain of salt. More analysis, and less alarmism, is needed.
There's a 50% chance that the 2°C climate threshold will be crossed by January 2048, according to the Metaculus prediction community.