Limiting global warming to 1.5°C would require rapid, far-reaching and unprecedented changes in all aspects of society, the UN’s Intergovernmental Panel on Climate Change (IPCC) said in a new report. According to the IPCC, 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 “Special Report on Global Warming of 1.5°C” was approved by the IPCC last week in Incheon, Republic of Korea. It 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.
“With more than 6,000 scientific references cited and the dedicated contribution of thousands of expert and government reviewers worldwide, this important report testifies to the breadth and policy relevance of the IPCC,” said Hoesung Lee, Chair of the IPCC.
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 that 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,” said Panmao Zhai, Co-Chair of IPCC Working Group I.
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.For instance, by 2100, global sea level rise would be 10 cm lower with global warming of 1.5°C compared with 2°C. The likelihood of an Arctic Ocean free of sea ice in summer would be once per century with global warming of 1.5°C, compared with at least once per decade with 2°C. Coral reefs would decline by 70-90% with global warming of 1.5°C, whereas virtually all (> 99%) would be lost with 2°C.
“Every extra bit of warming matters, especially since warming of 1.5°Cor higher increases the risk associated with long-lasting or irreversible changes, such as the loss of some ecosystems,” said Hans-Otto Pörtner, Co-Chair of IPCC Working Group II.
Limiting global warming would also give people and ecosystems more room to adapt and remain below relevant risk thresholds, added Pörtner. 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 report’s full name is “Global Warming of 1.5°C, an IPCC special report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty.”
According to the Greensburg Daily News, more than 40 governments around the world now price carbon emissions, either through direct taxes on fossil fuels or through cap-and-trade programs.
Massachusetts is one of nine states participating in the Regional Greenhouse Gas Initiative, a market-based effort to reduce power plant emissions under their jurisdiction by another 30 percent from 2020 to 2030. Other participants are Connecticut, Delaware, Maine, Maryland, New Hampshire, New York, Rhode Island and Vermont.