"Negative emissions technologies are in an early stage of development, posing uncertainties regarding their effectiveness, scalability, and environmental and societal impacts ... [Thus] we should not rely on unproven carbon removal techniques." 8/n

"We call for an Intergovernmental Panel on Climate Change (IPCC) special report that focuses on the perilous climate feedback loops, tipping points, and—just as a precaution—the possible but less likely scenario of runaway or apocalyptic climate change." 9/n