Atmospheric radiation modeling of galactic cosmic rays using LRO/CRaTER and the EMMREM model with comparisons to balloon and airline based measurements

Abstract

We provide an analysis of the galactic cosmic ray radiation environment of Earth's atmosphere using measurements from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) aboard the Lunar Reconnaissance Orbiter (LRO) together with the Badhwar‐O'Neil model and dose lookup tables generated by the Earth‐Moon‐Mars Radiation Environment Module (EMMREM). This study demonstrates an updated atmospheric radiation model that uses new dose tables to improve the accuracy of the modeled dose rates. Additionally, a method for computing geomagnetic cutoffs is incorporated into the model in order to account for location‐dependent effects of the magnetosphere. Newly available measurements of atmospheric dose rates from instruments aboard commercial aircraft and high‐altitude balloons enable us to evaluate the accuracy of the model in computing atmospheric dose rates. When compared to the available observations, the model seems to be reasonably accurate in modeling atmospheric radiation levels, overestimating airline dose rates by an average of 20%, which falls within the uncertainty limit recommended by the International Commission on Radiation Units and Measurements (ICRU). Additionally, measurements made aboard high‐altitude balloons during simultaneous launches from New Hampshire and California provide an additional comparison to the model. We also find that the newly incorporated geomagnetic cutoff method enables the model to represent radiation variability as a function of location with sufficient accuracy.

Space Weather Ballooning

“…Simultaneous launches of payloads like the one we have developed could reveal the 3‐D response of the atmosphere to solar storms over wide areas, not just in a single flight path over California. Indeed, we have already started multipoint balloon launches with a pair of simultaneous California‐New Hampshire flights in 2015 [ Joyce et al ., ].…”

Radiation Data Portal: Integration of Radiation Measurements at the Aviation Altitudes and Solar‐Terrestrial Environment Observations

“…It contains over 10 5 individual measurements. In addition to airplane in‐flight experiments, high‐altitude balloon experiments provide an essential grounding for detector cross‐comparison (Straume et al., 2016) and model verification (Joyce et al., 2016).…”

Essential science for understanding risks from radiation for airline passengers and crews

“…Exposure is greatest in long‐haul and high‐altitude flights, especially over the poles, and these flights are increasing. During times of calm space weather, travelers on flights from say, Chicago to Beijing, over the north pole get the equivalent radiation dose of a chest X‐ray (~0.1 mSv) [e.g., Meier et al , ; Bennett et al , , ; Joyce et al , ; Tobiska et al , ]. One millisievert is the recommended, annual general‐public limit.…”