Nearly 200 countries will begin online negotiations on Monday to endorse a scientific report from the United Nations that will lay the groundwork for anticipated summits this fall, aimed at preventing a global climate catastrophe. Amid record heatwaves, drought, and floods affecting three continents in recent weeks, exacerbated by global warming, the assessment from the Intergovernmental Panel on Climate Change (IPCC) comes at an opportune time. Richard Black, founder of the Energy and Climate Intelligence Unit in London and a leading expert, stated, "There is no doubt that the meeting will serve as a wake-up call."
He noted that the report comes just two weeks before the United Nations General Assembly, a G20 summit, and the "26th Conference of the Parties to the United Nations Framework Convention on Climate Change," involving 197 countries in Glasgow. The world has changed since the last comprehensive assessment by the IPCC in 2014 regarding past and future global warming.
As heatwaves and wildfires continue, doubts regarding the acceleration of warming and that the source is almost entirely human have dissipated, along with the misleading notion that climate impacts are problems of tomorrow. At another crossroads since the last IPCC report, the 2015 Paris Agreement was adopted, setting a collective goal of limiting global temperature rise to "well below" two degrees Celsius above late 19th-century levels.
Carbon pollution from fossil fuel combustion and methane leaks has already raised temperatures by 1.1 degrees Celsius so far, as emissions are once again increasing after a brief halt due to COVID lockdown measures, according to the International Energy Agency. The 2015 treaty also established an ambitious target of 1.5 degrees Celsius, yet many participants in the discussions assumed it would remain merely an aspirational goal and thus could easily be sidelined. A special report by the IPCC in 2018 highlighted the catastrophic consequences of a two-degree increase in global temperatures for humanity and the planet.
Professor Peter Thorn from Maynooth University, who played a key role in drafting the IPCC report, told AFP that 1.5 degrees Celsius "has become the de facto target" and is evidence of the IPCC's influence on shaping global policy. According to scientists' calculations, greenhouse gas emissions must be reduced by 50% by 2030 and completely eliminated by 2050 to keep global temperature rise within the 1.5-degree Celsius range. Furthermore, scientific understanding has evolved over the past seven years.
Climate expert Robert Faure, another lead author on the IPCC report and director of the Pierre-Simon Laplace Institute, mentioned, "We now have better models for climate predictions and longer monitoring periods, with much clearer indicators of climate change." The most significant breakthrough is known as attribution studies, which for the first time allow scientists to quickly determine the extent to which climate change has intensified a specific extreme weather event. For instance, the World Weather Attribution consortium was able to mathematically conclude just days after a severe heatwave impacted Canada and the western United States last month that such an occurrence would have been almost impossible without human-caused warming.
However, analysis after events differs from prior predictions, and the IPCC, established in 1988 to provide the necessary information for climate negotiations at the United Nations, has faced criticism from some who argue it has downplayed the threat, a pattern noted by science historian Naomi Oreskes at Harvard University, who believes it aims to remain on the "less dramatic" side of events.
Starting Monday, representatives from 195 countries, with assistance from scientists, will revise a "summary for policymakers" comprising about 20 to 30 pages, line by line and word by word. The virtual meeting, dedicated to the first part (covering physical science) of the three-part report, will take two weeks instead of the usual one, with publication of the document expected on August 9. The second part of the report, covering impacts, will be published in February 2022.
A leaked draft reviewed by AFP warned that climate change will reshape life on Earth in the coming decades, even if carbon pollution causing warming is controlled, and called for "transformational change" to prevent future generations from facing a far worse situation. The third part, to be revealed the following month, will examine solutions to reduce emissions. Based on published research, the report under review this week (even in optimistic scenarios) may forecast a temporary "overshoot" of the 1.5-degree Celsius target. There will also be a focus on events with "low probability and high risk," such as the melting of ice sheets that could raise sea levels by meters and the thawing of permafrost laden with greenhouse gases. Tim Lenton, director of the Global Systems Institute at the University of Exeter, stated, "The interactions that amplify change are stronger than we thought, and we may be approaching a tipping point."
