Key UN report to flag how ecosystems are under stress due to climate change
The Intergovernmental Panel on Climate Change (IPCC)’s Working Group (WG) II report, focussing on the limits of ecosystems, biodiversity hot spots and humans adapting to climate change, is due to be released on February 28.
The report drafted by the UN-monitored IPCC will highlight stressed ecosystems, which can possibly no longer tolerate the impact of climate change and reach tipping points.
IPCC WG II co-chair Hans-Otto Pörtner said on Thursday some ecosystems are approaching tipping points. Coral reefs are on a downslide and around 70 to 90% of their surface may be affected by the 1.5 degrees Celsius global warming, which will impact both coastal protection and the fisheries.
Portner said other ecosystems showing impacts such as tropical rainforests in the Amazon and Africa are losing the capacity to bind carbon dioxide.
“There will be a cross-chapter on losses and damages due to climate crisis which captures how physical changes due to climate crisis put ecosystems under stress,” said IPCC WG II co-chair Debra Roberts.
The report will also highlight how human society, climate systems, and ecosystems are connected, and hence impacts will affect all. “Humans are dependent on ecosystem services and species richness is an indicator of ecosystem health,” Portner said. He added humans also have hard limits with some parts of the planet becoming uninhabitable. Portner said this has been specified in the report.
The report will specify both hard and soft limits to adaptation. Hard limits relate to adaptive capacity an ecosystem has reached while soft limits are when the adaptive capacity has been reached but can be changed. Communities, which can adapt with the help of measures such as additional funds for infrastructure, are an example of a soft limit.
Roberts said the changes are unprecedented. “We have to act now and nobody at any level can be left out in dealing with this challenge but we do not seem to be able to put that response in place,” she said. Portner added: “We are at war with nature and that needs to turn around. That is the vision for human well-being.”
There will also be a chapter on the Covid and climate crisis in the report. “With an impoverished ecosystem, those species survive the best that are host carriers of pathogens. This is critical,” Portner said.
There will also be a regional focus and messaging in the report with details on human communities and their adaptive capacities and vulnerabilities.
The report is significant amid a consensus that even 1.5-degree Celsius warming will be dangerous for the planet leading to a breach of important tipping points—the big biophysical elements that regulate the climate systems such as the Greenland Ice Sheet.
Potsdam Institute for Climate Impact Research director Johan Rockstrom warned several tipping points were approaching instability and there will be cascading impacts on the climate systems when it takes place. He cited information from the Earth Commission and said there is now more support for the fact that 1.5-degree warming is the real boundary. “…many elements are approaching tipping points under well below 2-degree Celsius warming and at 1.5-degree warming,” he said at an India International Centre and Public Health Foundation of India webinar on Monday. He added this could pose a real danger to the climatic systems globally.