Limiting global warming to 1.5°C would require rapid, far-reaching and unprecedented changes in all aspects of society, according to a new report.
With clear benefits to people and natural ecosystems, limiting global warming to 1.5°C compared to 2°C could go hand-in-hand with ensuring a more sustainable and equitable society, the Intergovernmental Panel on Climate Change (IPCC) said on Monday.
The Special Report on Global Warming of 1.5°C will be a key scientific input into the Katowice Climate Change Conference in Poland in December, when governments review the Paris Agreement to tackle climate change.
Ninety-one authors and review editors from 40 countries prepared the IPCC report in response to an invitation from the United Nations Framework Convention on Climate Change (UNFCCC) when it adopted the Paris Agreement in 2015.
“One of the key messages that comes out very strongly from this report is we are already seeing the consequences of 1°C of global warming through more extreme weather, rising sea levels and diminishing Arctic sea ice, among other changes,” IPCC Working Group I co-chair Panmao Zhai said.
The report highlights a number of climate change impacts that could be avoided by limiting global warming to 1.5°C compared to 2°C, or more.
“Every extra bit of warming matters, especially since warming of 1.5°C or higher increases the risk associated with long-lasting or irreversible changes, such as the loss of some ecosystems,” IPCC Working Group II co-chair Hans-Otto Pörtner said.
Limiting global warming would also give people and ecosystems more room to adapt and remain below relevant risk thresholds, Mr Pörtner said.
The report also examines pathways available to limit warming to 1.5°C, what it would take to achieve them and what the consequences could be.
“The good news is that some of the kinds of actions that would be needed to limit global warming to 1.5°C are already underway around the world, but they would need to accelerate,” IPCC Working Group I co-chair Valerie Masson-Delmotte said.
The Paris Agreement adopted by 195 nations at the 21st Conference of the Parties to the UNFCCC in December 2015 included the aim of strengthening the global response to the threat of climate change by “holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels.”
Climate Council acting CEO Dr Martin Rice said the report is an urgent reminder that global warming poses a grave risk to humanity.
“Global temperatures have risen 1°C in the era following mass industrialisation and this has directly affected Australians, with worsening extreme weather events like heatwaves, droughts, bushfires and coastal flooding,” Dr Rice said.
“It’s clear that concerted action from all countries, particularly significant greenhouse gas polluters like Australia, is critical if we are to keep temperatures below the 1.5°C limit.
“Inaction has already cost us dearly. A 1.5°C world, our best possible future, will change our lives. It’s going to be tough to meet that target but we must strive to do so because a 2°C world would be much worse.”