Investigation of the Relationship between Storm Enhanced Density and Scintillation in Antarctica

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Geomagnetic storms driven by solar wind perturbations are dynamic events that can cause dramatic reconfigurations of plasma in the ionosphere, plasmasphere, and magnetosphere. These events cause mesoscale redistributions giving rise to the formation of storm enhanced density (SED) plumes and polar tongues of ionization (TOI). Plasma patches are formed from the tongue of ionization and subsequently propagate across the polar cap by the prevailing E x B drift of charged particles in the Earth's magnetic field. Steep density gradients are formed along the edges of polar cap patches and the TOI and SED features; these gradients are the source region for plasma instabilities that produce cascades of electron density irregularities in the background plasma. As radio signals propagate through the irregularities, rapid fluctuations or scintillations are produced in the received radio signal amplitude and phase. Scintillation presents a considerable space weather hazard, especially for the high-precision GPS observations and navigation. Comprehensive system level studies are needed to link cause to effect through observations of SED, TOI, and polar cap patch histories simultaneously with direct polar cap scintillation data. With this award, scientists will study the formation of TOI and polar cap patches over Antarctica, and observe the relationship of SED and TOI to polar scintillation, using a combination of GPS data from multiple existing platforms and from specially equipped GPS scintillation receivers located at three different Antarctic sites. Educational opportunities will be provided through MIT Haystack?s ongoing involvement in programs like the NSF Research Experiences for Undergraduates, Research Experiences for Teachers, and focused high school internships.