The perpetually ice-covered lakes in Antarctica’s McMurdo Dry Valleys preserve the dissolved remnants of black carbon from thousand-year-old wildfires as well as modern day fossil fuel use, according to a new study led by the University of Colorado Boulder.
The distinctive molecular signatures can provide researchers with a glimpse into the planet’s long history of combustion. Atmospheric black carbon, which is generated by wildfires or fossil fuel use, becomes preserved in glaciers, which in turn serve as long-term reservoirs and chemical time capsules.
The McMurdo Dry Valleys of Antarctica are the largest ice-free region of the continent and are considered a polar desert environment due to their low humidity, scarce precipitation and lack of plant life. During the summer, glacial melt feeds closed-basin lakes. Some of these lakes have saline bottom waters from drawdown events about a thousand years ago.