For years, most of us have envisioned climate change as a long-term problem that requires a long-term solution. But as the years pass—and with the calendar soon to flip over to 2013—without any substantial attempts to cut greenhouse gas emissions worldwide, this impression needs to change in a hurry.
According to a new paper published today in the journal Nature Climate Change, there’s a startlingly small number we need to keep in mind when dealing with climate change: 8. That’s as in 8 more years until 2020, a crucial deadline for reducing global carbon emissions if we intend to limit warming to 2°C, according to a team of researchers from a trio of research institutions—the International Institute for Applied Systems Analysis and ETH Zurich in Switzerland, along with the National Center for Atmospheric Research in Boulder, Colorado—who authored the paper.
They came to the finding by looking at a range of different scenarios for emissions levels in 2020 and projecting outward how much warming each one would cause for the planet as a whole by the year 2100. They found that in order to have a good chance at holding long-term warming to an average of 2°C worldwide—a figure often cited as the maximum we can tolerate without catastrophic impacts—annual emissions of carbon dioxide (or equivalent greenhouse gas) in 2020 can be no higher than 41 to 47 gigatons worldwide.
That’s a problem when you consider the fact that we’re currently emitting 50 gigatons annually; if present trends continue, that number will rise to 55 gigatons by 2020. In other words, unless we want catastrophic levels of warming, we need to do something, quickly