“A message of hope” but also a call to political decision-makers to do more and faster. This is the substance of the latest summary report of the Intergovernmental Panel on Climate Change (IPCC), its president, Korean economist Hoesung Lee, told AFP.
The IPCC published this Monday, March 20 the summary of its sixth evaluation report. A summary of the more than 10,000 pages of work he has published since his previous synthesis at the end of 2014. This synthesis, which will have no equivalent in the current decade, is “a survival guide for humanity” , underlined the UN Secretary General, António Guterres.
This scientific consensus of the IPCC will be the factual basis for the intense political and economic negotiations of the coming years. Starting with the UN climate summit in December in Dubai, the COP28, where an initial assessment of the efforts of each country within the framework of the Paris agreement will be unveiled and where the future of fossil fuels will be fiercely negotiated. Here are the main points to remember from the synthesis of nine years of IPCC work.
A warming that will reach 1.5°C from 2030-2035
Global warming will reach 1.5°C compared to the pre-industrial era from the years 2030-2035, warns the IPCC, while the temperature has already risen by almost 1.2°C on average. This projection is valid in almost all scenarios of human greenhouse gas emissions in the short term, given their accumulation over the past century and a half.
The CO2 emissions that would emanate from existing fossil infrastructures, if they are not equipped with means of capture, would be enough in themselves to tip the world towards 1.5°C. But “deep, rapid and sustained reductions in emissions […] would lead to a visible slowdown in global warming in about two decades,” the group of scientists also wrote on behalf of the UN.
“This summary report underscores the urgency of taking more ambitious action and shows that if we act now, we can still ensure a livable future for all,” said Hoesung Lee.
More serious impacts than previously estimated
“For any level of future warming, many climate-associated risks are higher than estimated” in the previous 2014 summary report, the scientists write. They are based on the recently observed multiplication of extreme weather events such as heat waves, and new scientific knowledge, for example on corals.
“Due to the inevitable rise in sea levels, the risks to coastal ecosystems, people and infrastructure will continue to increase beyond 2100,” they also point out.
The question of “loss and damage” caused by global warming and already suffered by some countries, in particular the poorest, will be one of the topics of discussion at COP28. “Climate justice is crucial because those who have contributed the least to climate change are disproportionately affected,” said Aditi Mukherji, one of the authors of the synthesis.
Today’s warm years among the coolest in a generation
“The hottest years we have experienced so far will be among the coolest within a generation,” summarizes Friederike Otto for AFP. The co-author of the synthesis represents this reality with a graphic colored in more or less dark red.
“Some things are easier to get governments to accept when it’s in infographics” rather than explicitly in text, she explains.
The past eight years have already been the hottest on record globally. In the future, they will therefore be among the coolest of the century, whatever the levels of greenhouse gas emissions. This observation underlines the need to combine efforts to adapt to climate change and those to reduce emissions so as not to make it even worse.
It costs less to invest than to suffer
“The economic and social benefits of limiting global warming to 2°C exceed the cost of the measures to be put in place”, assure the experts. But any additional procrastination would increase the step to be taken, notes the IPCC, while the world is already benefiting from the rapid progress of renewable energies.
“From 2010 to 2019, costs have fallen sustainably for solar energy (85%), wind power (55%) and lithium batteries (85%)”, recalls the synthesis. Besides the climate effect, accelerated and sustained efforts “would bring many co-benefits, particularly for air quality and health,” the scientists write. They do not hide the price to pay: “in the short term, actions involve high initial investments and potentially radical changes.”