Ice cores show pollution's impact on Arctic atmosphere
A Dartmouth-led study on ice cores from Alaska and Greenland found that air pollution from the burning of fossil fuels reaches the remote Arctic in amounts large enough to alter its fundamental atmospheric chemistry. The findings illustrate the long reach of fossil fuel emissions and provide support for the importance of clean-air rules, which the team found can reverse the effect.
The impact of pollution on the Arctic began as soon as widespread fossil fuel usage took hold during the industrial era, according to a report in Nature Geoscience. The researchers detected this footprint in an unexpected place -- they measured declines in an airborne byproduct of marine phytoplankton activity known as methanesulfonic acid, or MSA, captured in the ice cores when air pollution began to rise.
Phytoplankton are key species in ocean food webs and carbon cycles considered a bellwether of the ocean's response to climate change. MSA has been used by scientists as an indicator of reduced phytoplankton productivity and, thus, of an ocean ecosystem in distress.
