Yet another new scientific report is warning about the impending devastation linked to carbon dioxide emissions. Data from two important measuring stations shows carbon dioxide concentrations have gotten higher, and are staying higher for longer, than ever before. The reports suggest it won’t be long before the world’s carbon dioxide concentrations cross the so-called ‘point of no return’—especially if government leaders don’t work quickly to curb emissions. Scientists warn that levels may never drop back below a crucial 400 parts per million (ppm) threshold once that level is reached, even if emissions are greatly reduced.
One of the measuring stations in question is the Cape Grim Baseline Air Pollution Station located on the northwestern point of Tasmania, Australia. Recent reports indicate carbon dioxide levels are approaching 400ppm for the first time, and may never fall below the threshold again. The station is positioned in an area known for stable carbon dioxide readings, making it a good indicator of future global health.
Meanwhile, a second station in the northern hemisphere first registered carbon dioxide levels at the 400ppm milestone in 2013. National Oceanic and Atmospheric Administration (NOAA) reports that measurements taken at Mauna Loa in Hawaii have dipped below the threshold several times as seasonal cycles cause carbon dioxide concentrations to fluctuate. However, the global monthly average has been over 400ppm there since March 2015.
At Cape Grim, scientists reported a 399.9ppm reading on May 6, and they believe it was the last time that atmospheric measuring station will ever see carbon dioxide concentrations under 400ppm. This news, according to scientists from the Commonwealth Scientific and Industrial Research Organisation (CSIRO), which runs the Cape Grim station, is surprising and disconcerting.
“We wouldn’t have expected to reach the 400ppm mark so early,” David Etheridge, CSIRO atmospheric scientist, told the Guardian. “With El Nino, the ocean essentially caps off it’s ability to take up heat so the concentrations are growing fast as warmer land areas release carbon. So we would have otherwise expected it to happen later in the year. No matter what the world’s emissions are now, we can decrease growth but we can’t decrease the concentration. Even if we stopped emitting now, we’re committed to a lot of warming.”
Via The Guardian