Sampling for tephra (volcanic ash) in the Greenland ice commenced before Easter, starting with wide intervals from the  Holocene in the NGRIP core.  This is the beginning of many months’ work in the freezer, during which time hundreds of meters will be sampled from the different ice cores from the Holocene through to the Eemian.

Thin strips of ice are cut from the core (pictured) and melted in bottles in preparation for lab processing and microscope screening and tephra identification.  Tephra deposits identified in the ice are predominantly  in cryptotephra form –  invisible to the naked eye due to both low grain concentration and small grain size (typically 5  to 100 µm).

Individual, geochemically distinct tephra deposits, matched in both the ice and North Atlantic marine cores will help facilitate cross dating between records; a  goal of the Ice2Ice project.