Collaborative Research: Establishing an Iron Resonance Wind-Temperature Lidar at High-Frequency Active Auroral Research Program (HAARP) for Active Studies of Polar Aeronomy

The award supports a collaborative effort between researchers at the University of Alaska Fairbanks (UAF), Cornell University, G & A Technical Software Incorporated (GATS), the University of Colorado Denver (CU Denver), Virginia Polytechnic Institute and State University (VTech), and the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt, DLR) to build a state-of-the-art solid-state iron resonance wind and temperature lidar system (IRWTL) and to operate this instrument at the high-frequency active auroral research program (HAARP) facility located in Gakona, Alaska (62°N, 145°W). This instrument will be used to conduct a series of coordinated observations with the Ionospheric Research Instrument (IRI) at HAARP that will be operated in campaign mode centering upon three major heating experiments.

The Arctic atmosphere and the subauroral region are a natural laboratory for understanding plasma-neutral and dynamical coupling in the atmosphere and geospace. The lidar will measure the profile of the ion-neutral collision frequency needed for the determination of D-region electron density profiles from IRI HF radar data. A second application of coordinated IRWTL and IRI measurements is aimed at the investigation of the charge transfer mechanisms in dusty plasmas based on lidar observations of polar mesospheric clouds and radar observations of polar mesospheric summer echoes.

These coordinated measurements will also study the dynamical forcing of E-region winds using the technique of radar artificial periodic irregularities. The combined IRWTL and IRI observations will be used to study D-region structure as determined from the data collected from the detection of ELF/VLF waves generated by the IRI facility. These studies will have a variety of broader impacts including the study of fundamental processes in plasma physics, aerosols, fluid dynamics while advancing radio science and remote sensing technology and techniques.

The award will support research training and professional development of graduate students and two postdoctoral associates. The IRWTL will support the participation of both UAF undergraduate students and visiting students in scientific investigations and engineering projects. This effort fosters collaboration between three universities, an aerospace company, and a national space center.

The IRWTL lidar system will enhance the HAARP research infrastructure as a state-of-the-art solid state resonance lidar system using a frequency-stabilized Nd:YAG laser to achieve atmospheric illumination at the iron resonance emission wavelength at 372 nm. During geomagnetically active periods the auroral electrojet and auroral precipitation occur overhead at the HAARP site facilitating HF heating experiments to higher altitude ranges than otherwise would be the case.

The IRWTL observations will yield new wind and temperature measurements in the mesosphere-lower thermosphere in both daytime and nighttime throughout the year; these results would be compared with similar wind and temperature observations obtained at the Poker Flat sodium resonance wind and temperature lidar system located in central Alaska to search for evidence of large scale structure in polar mesospheric winds. The observations, analyses and results of this activity will contribute to national and international programs, including CEDAR and SCOSTEP programs.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.