The upgraded GLE database includes assessment of radiation exposure at flight altitudes

Abstract

The exposure to radiation due to cosmic rays at cruising aviation altitudes is an important topic in the field of space weather. While the effect of galactic cosmic rays can be easily assessed on the basis of recent models, assessments of the absorbed dose during strong solar particle events is rather complicated. A specific interest are events with energy about GeV/nucleon, which produce an atmospheric cascade registered by ground based detectors e.g. neutron monitors. Those events are known as ground level enhancements (GLEs) and can significantly enhance the radiation exposure at flight altitudes over the polar regions. A recent upgrade of the existing GLE database provides information on the estimated solar protons energy/rigidity spectra, the corresponding computed effective doses and the used bibliography. Using information retrieved from this upgrade we performed statistical analysis of maximum effective doses at commercial flight altitude of 35 kft during several GLEs, where the necessary information as energy/rigidity spectra of the solar protons is available. For the computations a recent model for assessment of effective dose due to cosmic ray particles was employed. A highly significant correlation between the maximum effective dose rate and neutron monitor peak count rate increase during GLEs is observed. Here, we propose to use the maximal count rate increase as a proxy for assessment of the effective dose at flight altitude during strong solar particle events.