A major United Nations science report has provided a stark reminder that time is running out for the world to avoid passing a dangerous global warming threshold.
The climate change report includes vast amounts of research on global warming compiled since the Paris climate accord was agreed in 2015, and was released by the UN Intergovernmental Panel on Climate Change (IPCC) on Monday (20 March).
Scientists from the IPCC said there needs to be drastic and deep cuts to greenhouse gas emissions to keep the average global temperature below 1.5C above pre-industrial levels. They added that every fraction of warming escalates the severity of heatwaves, heavy rainfall and flooding.
The UN Secretary-General, Antonio Guterres, has called for rich countries to quit coal, oil and gas by 2040, as well as an end to new fossil fuel exploration.
He said: “Humanity is on thin ice — and that ice is melting fast. Our world needs climate action on all fronts — everything, everywhere, all at once.”
Luke Murphy, IPPR associate director and head of its work on climate, nature, and energy, said: “Globally we’re not on track to meet our climate goals, the consequences of inaction are severe, and the time for bold action is now.”
He added that the UK government needs to “act now to reduce emissions.”
The report by hundreds of the world’s top scientists was finally approved by government delegations on Sunday evening (19 March) after being held up by a battle between rich and developing countries over emissions targets and financial aid to vulnerable nations.
It was supposed to be approved on Friday (17 March) at the end of a week-long meeting in the Swiss town of Interlaken.
Throughout the weekend officials from big nations such as China, Brazil, Saudi Arabia, the United States and the European Union haggled through the wording of key phrases in the text.
At the start of the meeting, UN Secretary-General, Guterres, called on delegates to provide “cold, hard facts” to drive home the message that there is little time left for the world to limit global warming to 1.5C compared with pre-industrial times. Global temperatures have already increased by 1.1C since the 19th century.
But Guterres insisted that the 1.5C target limit remains possible “with rapid and deep emissions reductions across all sectors of the global economy”.
The report authors said human activities have caused this warming and current policies are set to warm the Earth by a further 2C above pre-industrial temperatures by 2100.
Climate experts told NationalWorld that a 1C temperature change is “very important, and significant” as it could shift not only our climate but also our ecosystems and sea levels.
Experts said a 1C temperature change would cause more heatwaves, heavy rain, severe droughts and contribute to a substantial sea level rise which will continue for centuries.
Mike Kendon, from the Met Office National Climate Information Centre, said weather events in 2021 put into context how much a 1C rise is significant - from Storm Arwen in November to a new Northern Ireland temperature record in July and exceptional rain in October.
One expert said the UK will see more extreme weather more frequently, with the likes of heatwaves and droughts becoming the “new normal”.
‘Underscores the need for urgent action’
IPCC author Professor Peter Thorne said the report is “pretty clear” that we will “almost regardless of emissions scenarios, reach 1.5C in the first half of the next decade.”
He added: “There is some uncertainty about that. The real question is whether our collective choices between now and then mean we reach and stabilise at or around 1.5C or whether we blast right through 1.5C, crash through 2C and keep going.”
Dr Chris Jones, a Met Office climate fellow and a lead author of the IPCC report, said the report “reveals the sheer scale of the ambition required to avoid the worst consequences of climate change” and “underscores the need for urgent action.”
It will be the last such report for several years and sets out the scientific basis for this decade’s global climate action.
The Met Office also published analysis to coincide with the IPCC report. It said slashing global greenhouse gas emissions in half by 2030 would only leave a 50% chance of limiting the global average temperature to 1.5C.
It added that bigger cuts to emissions will become necessary.
Dr Jones added: “Without immediate and equitable mitigation and adaptation, climate change increasingly threatens societies and human wellbeing. But the report also shows the range of currently available and cost-effective mitigation and adaptation options.
“Renewed efforts to invest in sustainable development give us the best chance of a climate-resilient future.”
Dr Aditi Mukherji, another of the 93 authors of the synthesis report, said: “Climate justice is crucial because those who have contributed least to climate change are being disproportionately affected. In the last decade, deaths from floods, droughts and storms were 15 times higher in highly vulnerable regions.”
Observers said the IPCC meetings have increasingly become politicised with one issue at the current meeting being how to define which nations count as vulnerable developing countries.
This label makes countries eligible for cash from a “loss and damage” fund agreed on at the last UN climate talks in Egypt.
Delegates have also battled over figures stating how much greenhouse gas emissions need to be cut over the coming years, and how to include artificial or natural carbon removal efforts in the equations.
The United States has pushed back strongly against the notion of historic responsibility for climate change, despite being the nation releasing the biggest amount of carbon dioxide into the atmosphere since industrialisation.