Data stored in ice cores dating back 55 years bring new insight into atmospheric levels of a molecule that can significantly affect weather and climate.
Data stored in ice cores dating back 55 years bring new insight into atmospheric levels of a molecule that can significantly affect weather and climate.
Dimethyl sulfide (C2H6S) is a small molecule released by phytoplankton in the ocean, which can play a big role in regulating the Earth’s climate. It encourages cloud formation above the sea, and is often called an ‘anti-greenhouse gas’, since clouds block radiation from the sun and lower sea surface temperatures. At least some blocked heat will be retained in the atmosphere, however, so the effects can be complex. Researchers at Hokkaido University have charted evidence for increasing dimethyl sulfide emissions linked to the retreat of sea ice from Greenland as the planet warms. They report their findings in the journal Communications Earth & Environment.
Modelling studies have long suggested that the decline in Arctic sea ice could lead to increased dimethyl sulfide emission, but direct evidence for this has been lacking. Assistant Professor Sumito Matoba and colleagues have inferred dimethyl sulfide levels over 55 years by quantifying the related compound, methane sulfonic acid (MSA), in ice core samples from the south-east Greenland ice sheet. MSA is directly produced from dimethyl sulfide, serving as a stable record of dimethyl sulfide levels. This process is part of a variety of chemical interactions among aerosols in the atmosphere.
Read more at Hokkaido University
Image: Sumito Matoba (left) and Yoshinori Iizuka (right) on the southeastern dome in Greenland, drilling the ice core used in the study (Photo: Sumito Matoba).
