Extinction Rebellion protesters push a giant puppet depicting a burning koala in Brisbane, Australia [File: Darren England/EPA-EFE]

United Nations, March 20 (RHC)-- A major new United Nations report provides a sobering reminder that time is running out if humanity wants to avoid passing a dangerous global warming threshold.  The report by hundreds of the world’s top scientists is the capstone of a series that summarises the research on global warming compiled since the Paris climate accord was agreed upon in 2015.

It was approved by countries at the end of a weeklong meeting of the United Nations’ Intergovernmental Panel on Climate Change (IPCC) report in the Swiss town of Interlaken, meaning governments have accepted its findings as authoritative advice on which to base their actions.

At the start of the meeting, UN Secretary-General Antonio Guterres warned delegates the planet is “nearing the point of no return” and they risk missing the internationally agreed limit of 1.5 degrees Celsius (2.7 degrees Fahrenheit) of global warming since pre-industrial times.

That is because global emissions of carbon dioxide and other greenhouse gases keep increasing – mainly because of the burning of fossil fuels, deforestation, and intensive agriculture – when in fact they need to decline quickly.

Governments agreed in Paris almost eight years ago to try to limit temperature rise to 1.5C or at least keep it well below 2C (3.6F). Since then scientists have increasingly argued any warming beyond the lower threshold would put humanity at dire risk.

Average global temperatures have already increased by 1.1C (2F) since the 19th century, but Guterres insisted last week the 1.5C target limit remains possible “with rapid and deep emissions reductions across all sectors of the global economy”.

Monday’s report comes after the IPCC made clear two years ago that climate change is clearly caused by human activity and refined its predictions for a range of possible scenarios depending on how much greenhouse gas continues to be released.

The following year, it published a report concluding the effects of global warming are already being felt and nearly half the world’s population are “highly vulnerable to climate change”. Two months later, it laid out what needs to be done to reduce the harm from warming that is already inevitable and prevent a further dangerous rise in temperatures; the sharp drop in solar and wind power costs would make that easier, it noted.

Three further special reports by the IPCC focused on the oceans, land and 1.5C target. The next round of reports will not be published until the second half of this decade, by when experts say it could be too late to take further measures, allowing that ambitious goal to still be met.