Nature loss & climate change: linked problems, linked solutions.
A WWF report — Living Planet Report 2020: Too Hot to Handle: A Deep Dive into Biodiversity in a Warming World — examines links between climate change and nature loss, and considers how we might be able to reverse the two trends in parallel.
For much of the 20th century, the impact that our species had on nature came, overwhelming, from one direction: our destruction of natural habitats for agriculture, timber, housing and resource extraction. But, in 1999, evidence emerged of a new threat to biodiversity: climate change.
In that year, the first impact of the changing climate on a particular species was documented. Edith’s checkerspot butterfly, a species found in North America, was shown to have shifted its range northwards and to higher elevations in response to a warming climate. Since then, evidence of climate impacts has increased exponentially, including in 2016 the discovery of the extinction of the first mammal — the Bramble Cay melomys — as a direct result of climate change.
This is just one example of many in WWF’s Living Planet Report 2020. Subtitled Too hot to handle: A deep dive into biodiversity in a warming world, the report examines the links between climate change and nature loss and considers how we might be able to reverse the two trends in parallel.
The report notes that many species are precisely evolved for their habitats — the results of millions of years of evolution creating organisms that perfectly fit their ecological niches. Our destruction of habitats and our destabilizing of the climate system are upsetting the often fine balance that exists in nature.
For example, flying foxes are physiologically unable to tolerate temperatures above 42°C: a 2018 heatwave in Queensland killed an estimated one third of the global population of spectacled flying fox population. Reptiles — one in five species of which are threatened with extinction — often exist close to their thermal limits and are believed to be highly climate-sensitive.
Security experts consider climate change to be a ‘threat multiplier’ — a factor that risks making existing threats worse and transforming potential conflicts into real ones. So too with nature loss. The report cites recent analysis by an expert group of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) found that, across every indicator of biodiversity tested, the combined effect of climate change and land-use change is much worse than that of land-use change alone.
Such a finding is unsurprising. The climate is changing faster than natural systems can adapt. Some species are unable to move towards the poles as the world warms. Breeding patterns can fall out of sync with the availability of prey to feed the young. The interactions between climate change and land-use change make these impacts worse. The fragmentation of habitats can make it impossible for terrestrial animals to move to find more suitable conditions.
Conversely, of course, addressing the two issues simultaneously can multiply the benefits. The conservation and restoration of key ecosystems can both sequester large volumes of carbon while at the same time helping nature to thrive. However, the report identifies an urgent need for nature-based solutions to climate change to also include an explicit focus on climate adaptation — what one of its contributors, Bruce Stein of the National Wildlife Federation, describes as “biodiversity-focused adaptation”.
“While ‘ecosystem-based adaptation’ emphasizes nature’s value to people, biodiversity-focused adaptation is explicitly designed to reduce climate risks to species and ecosystems themselves,” he writes, noting that techniques for such “climate-smart conservation” are being increasingly put to use.
The COVID-19 pandemic is encouraging people to recognize the links between nature and human society, and to appreciate that we can’t have healthy communities without a healthy relationship with nature. The Living Planet report will hopefully also encourage us to recognize the inter-relationships between climate and nature loss, and to seek out solutions that seek to simultaneously address both.