Increased heat waves, droughts and floods, caused by human-induced climate change, are already exceeding the tolerance thresholds of plants and animals, according to a fresh warning issued Monday from the Intergovernmental Panel on Climate Change (IPCC).
The current global warming trend is causing the first extinctions of species and mass mortality events in trees and mammals, according to ecologist Camille Parmesan, one of the authors of the latest IPCC report.
“We have an increased risk of irreversible impacts such as the species’ extinctions,” said Parmesan, a University of Texas at Austin geological sciences adjunct professor, who briefed reporters a day prior to the report’s release.
The changes are appearing much faster, are more disruptive and more widespread than was expected 20 years ago, according to the IPCC.
“Any further delay in a concerted global action will miss the rapidly closing window to secure a livable and sustainable future for all,” cautioned another report co-author, Edwin Castellanos of the University of the Valley of Guatemala, in the call with reporters.
The IPCC also notes that millions of people are being exposed to acute food and water insecurity, especially in Africa, Asia, Central and South America, on small islands and in the Arctic.
The region forecast to be hardest hit: sub-Saharan Africa, which is expected to be most severely affected among the predicted number of people suffering from hunger in 2050 ranging from 8 million to up to 80 million people.
Under a higher level of warming scenario, up to 183 million additional people are projected to become undernourished in low-income countries due to climate change by 2050, according to the panel.
“Overall, the picture is stark for food systems. No one is left unaffected by climate change,” said Adelle Thomas, one of the report’s lead authors and a senior fellow at the University of the Bahamas.
“The more rapid we can take strong action to reduce greenhouse gas emissions, the less the severe impacts will be. And there are solutions out there, but right now, they're not there. There are not kind of transformative strategies being taken with regards to food systems to really ensure that we have a well-fed and nutritious human population and underlying ecosystem that can support food production,” said Thomas on the Sunday briefing call for reporters.
The IPCC report is considered a critically important one as world leaders are expected to rely on it to help form updated policies regarding carbon emissions and climate mitigation.
John Kerry, who is U.S. President Joe Biden’s climate envoy, characterized the report as “a dire picture of the impacts already occurring because of a warmer world and the terrible risks to our planet if we continue to ignore science.”
Kerry, a former secretary of state, added in a statement: “The question at this point is not whether we can altogether avoid the crisis — it is whether we can avoid the worst consequences.”
Monday’s document, compiled by 270 scientists from 67 countries, is the second chapter of the sixth assessment report by the IPCC and focuses on regional impacts of global warming and adaptation options for cities and coastal communities.
It was approved Sunday by the 195 member governments of the IPCC, which was created in 1988 by the World Meteorological Organization and the United Nations Environment Program.
The first chapter, issued last August, was described by United Nations Secretary-General Antonio Guterres as a “Code Red for humanity.”
That study noted that the world is now 1.09 degrees (Celsius) warmer than it was during the period between 1850 and 1900.
The IPCC scientists warn that fundamental societal shifts are required to overcome limits to adaptation, build resilience, reduce climate risk to tolerable levels, guarantee inclusive, equitable and just development, and achieve societal goals without leaving anyone behind.
Asked by VOA what should be the top mitigation effort to attempt to counter the worst of the scenarios forecast, some of the scientists cautioned against looking for one single solution.
“There isn't a silver bullet that's going to solve our greenhouse gas emissions and it's important to understand that every action matters,” replied Kristie Ebi, a global health professor at the University of Washington.
Simple and highly publicized projects, such as planting a trillion trees to solve global warming, will not work, said Parmesan, of the University of Texas Austin.
“One of the reasons is that there are many areas that are naturally not forested -- grassland savanna areas, peatland bogs. And there have been projects that have tried to plant forests into these areas and they have overwhelmingly been disasters,” she said.
What is critical is moving society away from fossil fuels as quickly as possible and relying on renewable sources of energy, said Castellanos, of the University of the Valley of Guatemala.
That is to be the topic of a report to be published by another IPCC working group next month.