Today, the Intergovernmental Panel on Climate Change (IPCC), the United Nations body to assess the science of climate change, unleashed their Special Report on the impact of global warming reaching 1.5°C above pre-industrial levels.

In short, one of the world's main climate targets – to keep global warming below 2°C – is not strict enough and could still lead to catastrophic, irreversible damage to our ecosystems. To avoid such a fate, we need rapid, immediate, and “unprecedented” change in the fields of energy, land use, infrastructure, and lifestyle

Over the past week, leading scientists and diplomats have been fine-tuning the content of the report in Incheon, South Korea. Poring over 6,000 peer-reviewed scientific studies, they attempt to provide a clear view of what’s at stake if climate change is not addressed and what we can do about it to stabilize a temperature rise of 1.5°C by 2100.

"This IPCC report is set to outline a rescue plan for humanity," said Jennifer Morgan, Executive Director of Greenpeace International, speaking at a press conference in South Korea on Thursday.

At the Paris Climate Agreement in 2015, international leaders agreed to keep global warming “well below 2°C above pre-industrial levels” with the hopes to limit this to just 1.5°C. As this report makes clear, the science now shows that the 2°C target won’t be enough. 

“1.5°C is the new 2°C,” Dr Chris Weber, Global Climate and Energy Lead Scientist at WWF, told IFLScience.

“The target of 2°C is now thought to be a lot worse than we originally believed, which means we really have to push for the 1.5°C target. It is not a viable choice to aim for 2°C based on what we know about extreme weather and other feedback cycles that take hold around 2°C.”

As just one of many examples, at least 99 percent coral reefs will be gone if we let the world warm by 2°C. Even at 1.5°C, the best case scenario coral reefs will decline a further 70 to 90 percent. You can find out more of these risks right here.

The world has already warmed by 1°C over the past 150 years due to human activity. As per the IPCC report, global warming is likely to reach 1.5°C as early as 2030 if we continue down this same path. To avoid stepping over this 1.5°C mark, the report argues that carbon dioxide emissions would need to fall by about 45 percent by 2030, then reach “net zero” by around 2050.

“Small policy changes aren’t going to get the job done, unfortunately. We are in the zone now where there are no easy options left,” added Dr Weber.

Another part of the Paris Climate Agreement was for countries to make commitments to reduce emissions to dampen the rise in global average temperature. If we stick to these commitments, we could still see a global warming of about 3°C by 2100, with warming continuing to creep up afterward. One thing is very certain: the world needs to seriously up its game when it comes to cutting carbon emissions. 

“It’s a bit like going to out for dinner but you don’t know how much the bill is going to be,” explained IPCC report contributor Professor Rachel Warren, from the University of East Anglia in the UK, also speaking to IFLScience.

“You all put in how much you think it will be and how much you think you should pay for dinner. But then the bill comes and it’s actually a lot more than the amount of money on the table. That’s effectively what’s happened with commitments to reducing carbon emissions.”