Ion Chromatography, also known as IC analysis, is helping to thaw out some of the climate mysteries of the Antarctic. To understand how the Earth and its climate will react to, mitigate and amplify climate changes, British scientists participating in the British Antarctic Survey are utilizing IC analysis to observe the past and study the present so that they can predict future climate changes.
Icy IC Analysis
Dr. Ailsa Benton, a scientist with the survey, makes use of IC analysis in her work at the Chemistry and Past Climate program. The first challenge is to unearth the samples to study with IC analysis. In order to do this, Benton collaborates with other scientists doing radar geophysics studies to identify ice core sites. Ice cores, formed when snow falls down on top of the ice cap, are cylinders of ice drilled from a glacier or ice sheet, containing layered sequences of compressed snowfall.
According to Benton, that snow has pockets of air trapped inside which reveal the atmosphere at a particular point in time. Drilling down deeper into the ice core exposes older and older layers of atmospheric precipitation.
“As we go back over time we can look at how precipitation, the weather and the climate have changed. The oldest site we have in the building at the moment is from a place called BerknerIsland, and it’s around 20,000 years old,” said Benton.
Chopping up the Ice Core
These ice core samples are then chopped up with a large band saw into the pieces that are needed for IC analysis. One of the pieces is then melted on a hot plate which is connected to a series of peristaltic pumps that divide the liquid sample into the different chemical channels for analysis. Measuring the major anions, such as chloride, fluoride, sulphate and nitrates, with fast, dual-channel IC analysis, Benson obtains one sample every 1.25 minutes.
“Once we have our annual layer markers and our chemical signals, we can put these together so that we know the age of our ice and how the environment has changed over the past,” Benson stated.
In a sometimes warmer climate, Minnesota-based Innovatech Labs uses IC analysis to identify and quantify anions and cations for businesses and organizations in a variety of industries.