Planning the Role of High-Power, High Frequency-Band Transmitters in Advancing Ionospheric/ Thermospheric Research Workshop; Gakona, Alaska; August 2013

National Academy Of Sciences, Washington DC

Investigators

Abstract

This is to organize a workshop to assess potential future roles of high-power HF (high frequency)-band transmitters in support of ionospheric and thermospheric research. It will focus, in particular, on the Alaskan HAARP (High Frequency Active Auroral Research Program) facility. HAARP is an ionospheric research program jointly funded by the U.S. Air Force, the U.S. Navy, the University of Alaska, and the Defense Advanced Research Projects Agency (DARPA). The key instrument at the HAARP station in Gakona, Alaska is a high-power radio frequency transmitter operating in the HF band, which is used to temporarily excite a limited area of the ionosphere. Historically, the "heater" communities that operate facilities like HAARP have been somewhat distinct from the research communities that study the ionosphere and thermosphere. The ionosphere and thermosphere constitute an important part of the near-Earth space environment where low-Earth orbiting satellites operate and through which communication and navigation signals are being transmitted. The ionosphere-thermosphere (IT) system is, however, subject to several geophysical forcings originating from the Sun. The interaction between the solar wind and the Earth's magnetosphere results in a fraction of the solar wind energy and plasma being transmitted into the magnetosphere, and subsequently into the ionosphere and thermosphere to produce auroras and other geomagnetic phenomena. Solar energetic particles penetrate into the upper and middle atmosphere to cause significant ionization and chemical effects. Solar ultraviolet and extreme ultraviolet radiation is the main source of energy for heating, ionization, and photochemical reactions in the thermosphere and ionosphere. The workshop will provide a useful venue for these communities to meet and to assess the utility and cost/benefits of HAARP in future IT research. Specifically, the workshop will have a major impact on the future of the HAARP facility as the Air Force has announced its intent to step back from its historical commitment to the facility and HAARP users look towards other sources of support, including the NSF. Absent these additional sources of funding, the facility would be closed and the land reclaimed in accordance with agreements dating back to the 1970s when the facility was an military radar site.