The stakes in tackling global warming are higher than ever, the UN’s climate science chief said on Monday as nearly 200 nations gathered to finalize what is sure to be a heartbreaking report on climate impacts. .
“The need for the Task Force 2 report has never been greater because the stakes have never been higher,” said Intergovernmental Panel on Climate Change (IPCC) Chair Hoesung Lee, in a live video.
Species extinction, ecosystem collapse, mosquito-borne diseases, deadly heat, water shortages and reduced crop yields are already significantly worse due to rising temperatures.
In the past year alone, the world has seen an unprecedented cascade of floods, heat waves and wildfires across four continents.
All of these impacts will accelerate in coming decades, even if the carbon pollution driving climate change is quickly brought under control, the IPCC report likely warns.
A crucial 40-page summary for policymakers – distilling underlying chapters totaling thousands of pages and reviewed line by line – is due to be released on February 28.
“It’s a real moment of judgment,” said Rachel Cleetus, director of climate and energy policy at the Union of Concerned Scientists.
“These are not just scientific projections about the future,” she told AFP ahead of the two-week plenary. “These are extreme events and slow-onset disasters that people are experiencing right now.”
The report will also highlight the urgency of “adaptation” – climate jargon meaning to prepare for devastating consequences that can no longer be avoided, according to a first draft seen by AFP in 2021.
In some cases, that means adapting to intolerably hot days, flash floods and storm surges has become a matter of life and death.
“Boost the atmosphere”
“Growing climate impacts far exceed our efforts to adapt to them,” said Inger Andersen, head of the UN Environment Programme, noting that climate change threatens to become a major driver of species loss.
The IPCC assessments – this will be the sixth since 1990 – are split into three sections, each with its own volunteer “working group” made up of hundreds of scientists.
In August 2021, the first physical science installment revealed that global warming is virtually certain to pass 1.5 degrees Celsius (2.7 degrees Fahrenheit), likely within a decade.
The Earth’s surface has warmed by 1.1°C since the 19th century.
“We’ve boosted the atmosphere with fossil fuels,” World Meteorological Organization chief Petteri Taalas said on Monday, comparing the result to the “enhanced performance” of Olympic athletes who used banned substances.
The 2015 Paris Agreement calls for capping global warming at “well below” 2°C, and ideally 1.5°C.
This report is sure to reinforce this more ambitious goal.
It will also point out that vulnerability to extreme weather events – even when worsened by global warming – can be reduced through better planning and preparation, according to the draft seen by AFP.
That’s not just true in the developing world, noted Imperial College professor Friederike Otto, pointing to massive flooding in Germany last year that killed dozens and caused billions in damage.
“Even without global warming, there would have been a huge rainfall event in a densely populated geography where rivers overflow very easily,” said Otto, a pioneer in the science of quantifying how much climate change makes more likely or intense extreme weather events. .
The report will focus on how climate change is widening already gaping gaps in inequality, both between regions and within nations.
The simple fact is that the people least responsible for climate change are those who suffer the most from its impacts.
The report is also likely to highlight dangerous “tipping points”, invisible temperature tripwires in the climate system for irreversible and potentially catastrophic change.
Some of them – like melting permafrost harboring twice as much carbon as in the atmosphere – could on their own be fueling global warming.
“There is a finite set of choices we can make that would allow us to move productively into the future,” said Clark University professor Edward Carr, lead author of one of the report’s chapters.
“Every day we wait and delay, some of those choices get harder or disappear.”