Here is the video from Dr. Chua’s 12/10/14 presentation at HacDC.
Dr. Damien Chua works at the Naval Research Laboratory and presents a survey of ionospheric variability and its effects on RF Communications. He first reviews the process of radio wave propagation and reflection in the ionosphere. He then examines how the ionosphere varies spatially and over various timescales. The drivers of ionospheric variability are traced out through the Earth’s magnetosphere and into interplanetary space to their solar origins. Chua reviews space weather measurements and indices available to the amateur radio community and provides an interpretation of them for understanding the space weather effects discussed above.