Faculty Candidate Physics Dept Seminar

March 5th, Monday

The Impact of Space Weather on the Earth’s High-Latitude Ionosphere

Dr. Gareth W. Perry

Univ. of Calgary, Canada

(Terrestrial Physics, Host: Gerrard)

*SPECIAL TIME: 2:45pm-3:45pm with 2:30pm teatime

*SPECIAL ROOM: FMH 408

At the turn of the 20th century, Guglielmo Marconi unwittingly provided some of the first evidence of the existence of a “reflecting layer” in the Earth’s upper atmosphere. Even though the existence of the layer (which we now call the ionosphere)wasn’t fully realized until later, its impact on global communications was immediate and immense. Today, the ionosphere is still a vital component of the global telecommunications infrastructure. Over-the-horizon monitoring and communications systems, as well as Global Navigation Satellite Systems (GNSS) rely on the presence and stability of the ionosphere to function. However, these systems are vulnerable to space weather – solar events which drive dynamic processes in the geospace environment. This is especially evident at high geographic latitudes, where complex processes in the Earth’s coupled magnetosphere-ionosphere system regularly produce large-scale (~100 km in scale size) ionospheric plasma density irregularities. In this presentation, the nature of the irregularities and their impacts on radio wave propagation conditions will be discussed. It will be shown that, even though Marconi’s experiments occurred over 100 years ago, we still lack a basic understanding of how radio wave propagation is affected by space weather at high-latitudes. Strategies and techniques for mitigating the negative impacts of space weather can only be developed by first understanding the influence of space weather and magnetosphere-ionosphere coupling in this region.