Detailed Solar Activity and Ionization Event Records in Polar Ice Caps

• Main Authors: Dreschhoff, Gisela A., Zeller, Edward J.
• Other Authors: KANSAS UNIV CENTER FOR RESEARCH INC LAWRENCE
• Format: Text
• Language: English
• Published: 1997
• Subjects: Astrophysics; Geology; Geochemistry and Mineralogy; Snow; Ice and Permafrost; *IONIZATION; *SOLAR ACTIVITY; *POLAR CAP; *NITRATES; *ICE CAPS; FREQUENCY; IONOSPHERE; POLAR REGIONS; GLOBAL; CORES; SITES; PROTONS; SEQUENCES; HIGH ALTITUDE; HEMISPHERES; SOLAR CYCLE; WHITE LIGHT; ANTARCTIC REGIONS; SOLAR FLARES; SUN; GREENLAND; SOLAR COSMIC RAYS; SOLAR DISTURBANCES; SOLAR-TERRESTRIAL INTERACTION; SPACE WEATHER; PROTON EVENTS; SPE(SOLAR PROTON EVENTS); Antarctic; Greenland; The Antarctic; Antarc*; Ice; Ice cap; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA334829; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA334829

Nitrate analyses were made of ice cores taken from high altitude sites on the Antarctic plateau and central Greenland. The 430 year nitrate record from the Greenland ice cap is believed to provide an estimate of the occurrence frequencies and number of major solar flares / solar proton events. The results include: (1) Observed historical white light flares can be expected to be associated with major solar proton events, (2) The SPE's recorded in the nitrate sequence are most likely large proton fluence events originating near the central meridian of the sun as viewed from the earth, (3) Large events occurred at the end of the 18th century, (4) Increased solar activity for several solar cycles preceding deep and prolonged solar minima, (5) Deep minima are recorded in both polar regions, (6) The nitrate record provides an almost complete history of ionospheric conditions in terms of individual ionization events as well as hemispheric or global effects via ionospheric-thermospheric coupling.