A new study by Australian scientists projects that the world will likely warm between 2 and 6 degrees Celsius (3.6 to 10.8 degrees Fahrenheit) from pre-industrial levels by 2100. The study published in Nature Climate Change finds that exceeding the 2-degree threshold is very likely under business-as-usual emissions scenarios even as scientists have long warned that passing the 2-degree mark would lead to catastrophic climate change.

“This study ultimately shows why waiting for certainty will fail as a strategy,” lead author Roger Bodman from Victoria University said. “Some uncertainty will always remain, meaning that we need to manage the risks of warming with the knowledge we have.”