Another property of the core is being studied by Dr. Julie Palais of the University of New Hampshire and Dr. Michael Ram of University of New York at Buffalo. The amount of dust carried to Greenland varies with the amount of land where dust can be picked up by the wind, the strength of the wind, and also, with volcanic activity and fires. Like the isotopes and ions, there is an annual signal of dust in the core. A dust peak is often found in the spring section of an annual layer. Like isotopes these can be counted to determine the age of the core.
Volcanoes can produce large quantities of particles and leave a record in the ice.
Scanning electron micrographs of the particles from a particularly large dust peak in an ice core may reveal that it is from a known volcano and allow a firm date to be placed on that section of core. For prehistoric times, the dust record is a key tool for reconstructing a history of volcanic activity. Further at the end of a glacial advance there is often a period of dustiness as the glaciers retreat and leave large unvegetated land areas. These periods can be detected by high levels of dust in the core. An important baseline measurement is electrical conductivity.