New research has shown that rising sea levels could be greatly slowed if certain fast cycling pollutants are cut from the numerous emissions being pumped into the atmosphere.
According to the research, published in the journal Nature Climate Change this week, cutting levels of methane, soot, refrigerants, and gases that lead to the formation of ground-level ozone, could slow the annual rate of sea level rise by anywhere between 25% to 50%.
“To avoid potentially dangerous sea level rise, we could cut emissions of short-lived pollutants even if we cannot immediately cut carbon dioxide emissions,” says Aixue Hu of the National Center for Atmospheric Research (NCAR), the first author of the study. “This new research shows that society can significantly reduce the threat to coastal cities if it moves quickly on a handful of pollutants.”
“It is still not too late, by stabilizing carbon dioxide concentrations in the atmosphere and reducing emissions of shorter-lived pollutants, to lower the rate of warming and reduce sea level rise by 30 percent,” says Veerabhadran Ramanathan of Scripps, who led the study. “The large role of the shorter-lived pollutants is encouraging since technologies are available to drastically cut their emissions.”
The research team focused on studying methane, soot, refrigerants, and gases that lead to the formation of ground-level ozone due to their relative fast-cycling through our atmosphere. These gases and particles last anywhere from a week through to a decade, a short time when compared to carbon dioxide’s atmospheric lifespan of more than a century.
The new research was founded upon previous research done by paper-co-author Ramanathan and Yangyang Xu of Scripps, which showed that a sharp reduction in these short-lived pollutants which began in 2015 would offset temperatures by up to 50% by 2050.
In their new paper, the researchers took these emission reductions and applied them to sea level rise, and found that the cuts could have an impact of reducing the rise by 22% to 44% by 2100, depending on the extent to which the emissions were reduced.
Interestingly, the research also showed what would happen if cuts were not introduced soon. According to the data, delaying cuts in these short-lived emissions until 2040 would reduce the impact the cuts would have on sea level rise by approximately a third.
Furthermore, the researchers concluded that if humanity managed to get their act together enough to reduce carbon dioxide alongside these four pollutants, total sea level rise would be lessened by at least 30% by 2100.
“Without diminishing the importance of reducing carbon dioxide emissions in the long term, this study shows that more immediate gains from shorter-lived pollutants are substantial,” said co-author, Claudia Tebaldi of Climate Central. “Cutting emissions of those gases could give coastal communities more time to prepare for rising sea levels. As we have seen recently, storm surges in very highly populated regions of the East Coast show the importance of both making such preparations and cutting greenhouse gases.”
“It must be remembered that carbon dioxide is still the most important factor in sea level rise over the long term,” says NCAR scientist Warren Washington, a co-author. “But we can make a real difference in the next several decades by reducing other emissions.”
