In the given context IPCC outlines several different emissions scenarios in the report. Conclusion is that the world could reach 1.5 degrees already in the early 2030s under all emissions scenarios, leading to the prediction that global warming is going to reach a tipping point by 2040.
Even under a net-zero scenario, by 2040 global warming could reach 1.7 degrees relative to pre-industrial times. Although the world might pass the 1.5-degree goal in the interim, even while pursuing net-zero emissions, temperatures could later drop again as the global output of emissions starts to decline in pursuit of that target. In comparison, a worst-case scenario would most likely result in warming of 2.4 degrees from 2041 through 2060, and global warming would continue to climb to 4.4 degrees by the end of this century relative to pre-industrial levels.
The report says that while some of effects of climate change (rising sea levels etc.) may be irreversible, meaningful international action could still limit warming to 1.5 °C as an important threshold.
IPCC experts underline that stabilizing the climate will require strong, rapid, and sustained reductions in greenhouse gas emissions, and reaching net zero CO2 emissions. Limiting other greenhouse gases and air pollutants, especially methane, could have benefits both for health and the climate.
Following the release of the report, COP26 President and UK MP Alok Sharma called on governments and businesses to act on supporting the 1.5 °C goal.