Estimate of Radiation Exposure to Commercial Air Travelers and Avionic Systems During an Extreme Space Weather Event

The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model is used to estimate radiation exposure to commercial aircrew and passengers for a Carrington-class solar-geomagnetic storm. A range of plausible proton spectral fluence rates during the 1859 Carrington event is determined using the softest and hardest spectral shapes observed during the space age, with the > 30 MeV integral proton flux constrained by nitrogen deposits measured in ice cores. The records kept by Carrington, along with magnetometer measurements in India during the event, provide critical information necessary to reconstruct the solar wind and interplanetary magnetic field parameters. The above information is sufficient to uses as input to the NAIRAS model and estimate the effects of Carrington-class radiation and geomagnetic storms on the atmospheric ionizing radiation field from the surface to low-Earth orbit. In addition to presenting the potential health risks to air travels during an extreme space weather event such as a Carrington-class event, the risks to aviation microelectronic systems are also discussed.