Solar Proton Events from a 180 Year Depth Profile of Nitrate Concentrations from the Central Greenland Ice Sheet

• Main Authors: Dreschhoff, Gisela A., Zeller, Edward J.
• Other Authors: KANSAS UNIV CENTER FOR RESEARCH INC LAWRENCE
• Format: Text
• Language: English
• Published: 1993
• Subjects: Astrophysics; Geology; Geochemistry and Mineralogy; Snow; Ice and Permafrost; Electricity and Magnetism; *PROTONS; *DEPTH; *SOLAR ACTIVITY; *ICE; FREQUENCY; ANOMALIES; SURFACES; MELTING; AUTOMATIC; GREENLAND; NITRATES; SOLAR FLARES; GEOPHYSICS; SAMPLING; SIGNALS; PROFILES; ELECTRICAL CONDUCTIVITY; CORES; RESOLUTION; PE61102F; WUAFOSR2311AS; Greenland; Ice; ice core; Ice Sheet; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA272888; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA272888

Operations have been concentrated on the micro-resolution analysis of the 120 meter ice core that was collected in Greenland in June, 1992. Thus far, 64 meters of the ice core have been sampled and a total of over 4000 individual samples have been analyzed for both nitrate and electrical conductivity. It has been possible to identify a number of specific anomalies in both the nitrate and the electrical conductivity records. Strong nitrate anomalies related to known solar flares have been identified, and it will become possible to delineate a signal of solar activity well beyond the known geophysical records. It has also been observed that periods of known low solar activity also correlate with lower than normal nitrate concentration and yearly nitrate flux. A new automatic ice core melting apparatus has been designed and built that will permit sampling the remaining ice cores at a higher resolution than was previously possible. This is a significant advantage because deeper ice cores are more compacted and the higher sampling frequency will maintain nearly the same time resolution as that obtained nearer the surface.