The world is about to cross 1.5°C.
Within the next few years, average global temperatures are expected to cross the 1.5°C increase above pre-industrial levels that scientists defined as critical to limiting the worst impacts of climate change. A new report from the UN Environment Programme (UNEP), Limiting Overshoot, concludes that global action to cut emissions has not been fast enough to avoid crossing the threshold. Even full implementation of every national climate plan, plus additional net-zero targets, leaves the world peaking above 1.5°C.
Warming beyond 1.5°C means faster sea level rise, more extreme heat, and intense wildfires, and greater risk to ecosystems that birds and people depend on. It also increases the likelihood of crossing irreversible tipping points in Earth’s climate systems, such as the melting of ice sheets. The goal remains a return to 1.5°C, which means following an “overshoot, peak and decline” pathway of limiting how far temperatures rise past 1.5°C so they hopefully peak as low as possible, then bringing them back under the threshold. According to the UNEP report, this is our best remaining option. Avoiding every fraction of a degree of temperature rise, and shortening the time spent above 1.5C, meaning the time in overshoot, reduces risks and damages and improves the chances of bringing temperatures back down.
What rising temperatures mean for birds and communities
Birds are sentinels of environmental change and help us make sense of this developing story. Audubon’s Survival by Degrees report found that vulnerability to climate change increases with every increment of warming: at 1.5°C, 47 percent of 604 North American bird species are vulnerable to range loss and potential extinction, and at 3°C, 63 percent are vulnerable. Therefore, holding peak warming closer to 1.5°C instead of 3°C lowers the risk for 76 percent of vulnerable species and 146 species are no longer vulnerable. For example, at 3°C, the Wood Thrush is highly vulnerable and projected to lose 57 percent of its breeding range. At around 1.5°C, its vulnerability is projected to be low, providing a greater likelihood of long-term survival for the species
Higher temperatures as a result of climate change also fuel distinct threats that further compound the risks to birds as well as people. Across the lower 48 states, extreme spring heat at 3°C would affect nearly every bird species during their breeding season, and more than 95 percent would face two or more climate-related threats, from heat and fire weather to extreme floods, droughts and sea-level rise. However, at 1.5°C, most species and communities across the United States would face only one climate change related threat.
A safer climate for birds means a safer climate for people too. Protecting birds from the threats they face will help safeguard communities from damages like coastal erosion, extreme fire weather, droughts, floods, and heatwaves.
Net-zero can halt warming. Net-negative brings temperatures down.
The UNEP reports tells us that reaching net-zero emissions can halt warming, but bringing temperatures back below 1.5°C will require “net-negative emissions,” a period where more carbon is removed from the atmosphere than released. Both steps require a transition to renewable energy, and that infrastructure depends on a modernized grid. About a third of existing and planned transmission lines overlap areas important to birds, according to Audubon’s Birds and Transmission report, so Audubon works with developers on careful routing and bird-friendly design elements to reduce risks while also building the transmission network needed to address climate change.
Nature-based solutions are another key to climate change mitigation and adaptation. The UNEP report lists reforestation and ecosystem restoration among the many nature-based solutions to climate change mitigation. Habitat conservation stores and sequesters carbon while also sheltering birds and building overall ecosystem resilience. This is a win-win for birds and people. Audubon’s Natural Climate Solutions report found that the places birds will depend on most as the climate changes are also areas of high carbon value, and conserving and restoring priority forests, grasslands, wetlands and other habitats could deliver up to 23 percent of the U.S. 2016 Paris Agreement commitments to emissions reductions.
Every acre counts
Every acre of habitat conserved helps slow climate change. Every fraction of a degree of warming avoided lowers the vulnerability and risk to birds and people. That’s why Audubon and partners are working to advance nature-based solutions and responsibly planned clean energy and transmission. And we can all play a part.
About two-thirds of priority habitat for bird conservation in the U.S. is privately owned, which puts farmers, ranchers and forest owners at the center of conservation, along with the people who buy what their land produces. Audubon Conservation Ranching certifies ranches managed for birds: more than 100 ranches are participating in this voluntary program, covering nearly 3 million acres. Their beef and bison carry the Audubon Certified Bird-Friendly seal. Grasslands hold about a third of the carbon stored in land soils, so protecting them serves the climate as well as habitat for grassland birds, which are declining faster than any other group of birds in North America.
Forests store more carbon than any other terrestrial ecosystem and shelter climate-vulnerable birds like the Wood Thrush. Buying maple syrup from Audubon’s Bird-Friendly Maple program recognizes producers who manage their sugarbush for nesting and migratory birds. In our own outdoor spaces, we can create bird-friendly communities by growing native plants and taking steps to reduce threats like window collisions.
This UNEP Limiting Overshoot report describes the challenge in stark terms. Birds help us understand the solutions, including what we can do as individuals to make a difference for birds and people.
