Scientists have released what can be seen as the most urgent and far-reaching call yet for world governments to cut their greenhouse gas emissions and stop global warming.
They warn of dying corals, melting sea ice and rising sea levels. These effects are inevitable with any level of global warming, but the conclusion of the report is that they will be far worse if the temperature increase is 2C, compared to a more ambitious target of 1.5C.
The report is the result of years of research and then a week of frantic negotiations between scientists and government officials at a meeting in South Korea.
But what exactly does the report say, and what does it mean for the global community?
What is the IPCC report?
Its goal was to gather together all the available scientific literature and produce a report that laid out two future scenarios. One in which the Earth’s average temperature was allowed to increase by 1.5C above pre-industrial temperatures (since around 1850), and one in which it increased by 2C.
The report has taken over two years to produce and included the assessment of more than 6,000 scientific studies.
The point was to create a document that could help those in power with their efforts to ward off climate change and support sustainable economic development while also eradicating poverty.
How did it come about?
The report was commissioned by the United Nations (UN) after the Paris climate agreement in 2015.
At the time, a coalition of rich and poor nations pushed for a commitment to “pursue efforts to limit the temperature increase even further to 1.5C” as well as the “well below” 2C target set by the agreement.
The UN then asked its scientific body the Intergovernmental Panel on Climate Change (IPCC) to get to work finding out what this stretch goal would mean, and how it could be achieved.
What were its main conclusions?
Things are not looking good. We are on track to reach 1.5C between 2030 and 2052 if temperatures continue to increase at the current rate, and 3C by the end of the century.
Once we hit 2C warming, the world will be a profoundly different place. There will be almost no coral reefs remaining, the Arctic will be completely devoid of ice during summer at least once a decade, and huge numbers of animals and plants will become extinct as their habitat becomes smaller and smaller.
The impact for humans will be enormous, particularly in areas already vulnerable such as the low-lying coastal regions of Bangladesh and Vietnam, and island territories like Kiribati and the Maldives. Sea level rise will drive millions from their homes, and crop yields will fall dramatically in sub-Saharan Africa, Southeast Asia, and Central and South America.
Is there any reason to be hopeful?
Yes, but it’s going to take serious effort at every level of society. The researchers behind the report used words like “unprecedented” to describe the kind of changes that will need to take place if we are going to stay below the 1.5C target.