Yesterday, the Intergovernmental Panel on Climate Change (IPCC) released its latest large global assessment report on the impacts of climate change and how we might respond. The striking thing about this latest iteration is the strong focus on ecosystems, biodiversity and extinction not seen in previous reports.
The last such report, published in 2014, largely spoke of biodiversity impacts as a future matter. It’s now clear that the future is here. The very first line of substantive comment in the 2022 edition is: “This report recognizes the interdependence of climate, ecosystems and biodiversity, and human societies, and integrates knowledge more strongly across the natural, ecological, social and economic sciences than earlier IPCC assessments.”
While the report talks about many types of impacts, from severe weather, to health to food and water security, the IPCC has done a somewhat remarkable job of putting the impacts to nature right up front and then connecting those to the effects for people and communities.
The first two findings concerning the impacts observed to date are worth a closer look with regards to the work Defenders does. The first, which the IPCC concludes with “high confidence,” is that: “Widespread, pervasive impacts to ecosystems, people, settlements, and infrastructure have resulted from observed increases in the frequency and intensity of climate and weather extremes, including hot extremes on land and in the ocean, heavy precipitation events, drought and fire weather.”
The second observation gets into more detail about climate change impacts to ecosystems that the IPCC has “high confidence” about:
“Climate change has caused substantial damages, and increasingly irreversible losses, in terrestrial, freshwater and coastal and open ocean marine ecosystems. The extent and magnitude of climate change impacts are larger than estimated in previous assessments. Widespread deterioration of ecosystem structure and function, resilience and natural adaptive capacity, as well as shifts in seasonal timing have occurred due to climate change, with adverse socioeconomic consequences. Approximately half of the species assessed globally have shifted polewards or, on land, also to higher elevations. Hundreds of local losses of species have been driven by increases in the magnitude of heat extremes, as well as mass mortality events on land and in the ocean and loss of kelp forests.”
Given Defenders recent call on the Biden Administration to create a National Biodiversity Strategy, it was promising to see the report also warns of accelerating biodiversity loss in the late 21st century. “Biodiversity loss, and degradation, damages to and transformation of ecosystems are already key risks for every region due to past global warming and will continue to escalate with every increment of global warming.”
The good news is that if we can limit warming to 1.5°C, we can avoid severe impacts —the red and purple colors in the figure above—for most terrestrial, freshwater and ocean ecosystems. For instance, half as many terrestrial species face extinction at 1.5°C as do if we reach 3°C. Later this month, the IPCC will publish the third and final volume of the current Assessment, which will explore the ways that we can get there. In the interim, the report recommends steps to manage biodiversity and connect ecosystems. Defenders is already at the forefront of those actions, like restoring natural springs for manatees and protecting the Sagebush Sea, which provides vital habitat for sage-grouse and hundreds of other species.
If there’s one thing the report makes clear, it’s that there’s no time left for inaction. We’re at the end of the rope. It states: “Climate change is a threat to human well-being and planetary health. Any further delay in concerted anticipatory global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a liveable and sustainable future for all.”