Date of Award


Document Type


Degree Name

Master of Science in Applied Physics


Department of Engineering Physics

First Advisor

Christopher G. Smithtro, PhD


This research takes an existing ionospheric model and modifies it to include the effects of solar flare activity. Solar flares are a localized explosive release of magnetic energy that appears as a sudden, short-lived brightening in the sun’s chromosphere. This additional energy is deposited in the earth’s ionosphere, temporarily changing its properties, which can affect military communications. Studying the effects of moderate solar flares will improve our understanding of the ionosphere’s response, leading to better operational models. Modification of the model is accomplished by adding a flare irradiance model to represent solar irradiance changes due to a flare. The irradiance output is then used to calculate the photoionization rates, electron impact ionization rates, and electron heating rates in the ionospheric model. After the results of this integration are validated, two moderate flares are modeled and then compared to ionospheric measurements from Bear Lake Observatory. It is found that the new model is able to accurately reflect the response of the E and lower F region of the ionosphere, but above the F2 peak the electron temperature does not increase as initially expected. Future work will need to resolve this discrepancy so that the model can accurately develop the ionosphere’s response to solar flares.

AFIT Designator


DTIC Accession Number