Our global carbon budget to avoid permanently reaching 1.5 degrees of warming is smaller than we previously thought, new research says. A study published this week in the journal Nature Climate Change found that the planet can only emit another 250 gigatons of carbon dioxide for a 50% chance of reaching 1.5 degrees Celsius of global warming by the end of this decade.
“The lack of progress on emissions reduction means that we can be ever more certain that the window for keeping warming to safe levels is rapidly closing.” But why exactly is 1.5 degrees Celsius of warming so important? That number may not seem big, but the planet has warmed 1.2 degrees Celsius since the preindustrial era began. This had already fueled worsening extreme weather events. Avoiding further warming beyond the threshold is necessary to stop these events from getting even worse.