This data set contains nitrate and conductivity measurements taken from the Greenland Summit Ice Sheet Project (GISP) H core. GISP was a decade-long project during the 1970s and early 1980s to study the climatic record stored in ice sheets, and involved scientists and funding agencies from Denmark, Switzerland and the United States. Nitrate and electrical conductivity measurements aid in the dating of ice cores by providing information about past volcanic eruptions and climate change. This data set involves a total of 7776 individual analyses from the surface of the core to a depth of 122 meters. The analyses were performed simultaneously on the same 1.5 cm ice core sample for each data series.