‘Unprecedented’ carbon reduction necessary to prevent catastrophe, IPCC warns
The Intergovernmental Panel on Climate Change (IPCC) has published a report calling on governments to take drastic, far-reaching and immediate action to keep global warming within 1.5°C and prevent catastrophic climate change.
The report was approved by the IPCC in Incheon, South Korea, this weekend. It cites 6,000 scientific references, was written by 91 authors from 40 countries and has had contributions from thousands of scientific and government reviewers.
The report described some of the existing impacts of climate change, such as annual extreme weather events, and laid out the steps necessary to prevent complete environmental catastrophe: this includes halving global carbon emissions within just 12 years.
“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 the IPCC Working Group I, which examines the physics of climate change.
The report says that limiting global average temperature rises to within 1.5°C above pre-industrial levels – rather than the 2°C agreed in the Paris Accord in 2015 – could prevent some of the most cataclysmic impacts of climate change. These would likely include reducing global sea level rises by 10cm by 2100, lowering the likelihood of an Arctic Ocean with no sea ice in summer, and could preserve 10-30 per cent of coral reefs (which would otherwise be almost entirely destroyed).
Limiting rises to 1.5°C – while still highly destructive – would give humans and ecosystems more room to adapt to the change in climate, also ensuring a fairer and healthier future compared with the alternatives, the author say.
Hans-Otto Pörtner, co-chair of the IPCC Working Group II, which examines climate change impacts, adaptation and vulnerability, said that: “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.”
Achieving this is not physically impossible, but would require “unprecedented” and “rapid and far-reaching” climate mitigation action in many areas, the IPCC warns. World leaders would need to commit to reducing carbon emissions from human sources by 45 per cent from 2010 levels by 2030, and reaching “net zero” emissions by 2050 (requiring any remaining emissions to be negated with carbon removal technologies, which have not yet been demonstrated on a large enough scale). So far, a handful of countries, cities, and states have pledged to go entirely carbon neutral within limited timeframes.
Cutting emissions to the extent necessary will require overcoming financial, human resource and technological constraints, as well as changing public attitudes and values.
The authors predict that at present, the world is on track to reach global warming of 1.5°C between 2030 and 2052.
“This report gives policymakers and practitioners the information they need to make decisions that tackle climate change while considering local context and people’s needs. The next few years are probably the most important in our history,” said Debra Roberts, co-chair of the IPCC Working Group II.
Responding to the report, Kaisa Kosonen of Greenpeace Finland told BBC News that: “Scientists may want to write in capital letters ‘ACT NOW, IDIOTS’, but they need to say that with facts and numbers - and they have.”
Claire Perry, the minister for energy, has stated that “real action is needed” and that the UK government is due to outline its next steps to confront the “global crisis” over the next few days.
The next major international climate change conference will be held in Poland in December, following last year’s UN Framework Convention on Climate Change in Bonn, Germany, where US state leaders picked up the climate mitigation effort abandoned by the White House following Donald Trump’s withdrawal of the US from the Paris Agreement.