Ionosphere
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Ionospheric research at Millstone Hill has a long history beginning in
the1960s when the incoherent scatter radar (ISR) became operational. The
Millstone Hill ISR, the only NSF
Upper Atmosphere Facility in the continental United States, measures height profiles of a variety of important
ionospheric parameters.
Earlier ionospheric investigations have resulted
in many scientific discoveries on local and subauroral ionospheric
features [see ASG publications];
recent emphases include the use of large scale and
long-term databases collected by ISRs at Millstone Hill and elsewhere over
the world [see here for a
map of world ISRs]. These efforts further our understanding of
ionospheric (and thermospheric)
climatological behaviors on various
spatial and temporal scales. Ionospheric climatological research topics include plasma temperature
climatology, annual and semiannual ionospheric variations, ionospheric
variability, and upper atmospheric longterm trends of variation.
Ionospheric empirical models are important tools for many research, engineering and educational efforts. Based on long-term databases, a series of ionospheric empirical models has been developed, including local models for each of the seven ISR sites in the world, regional ionospheric models for the American Sector, and a high-latitude plasma convection model. An advantage of these ISR models is the possibility for synthetic studies of ionospheric characteristics of multiple parameters over American Sector, especially, in subauroral-auroral zones where a number of space physics processes take place. Using these models, Virtual Incoherent Scatter Radars (VISRs) provide near real-time estimates for current ionospheric conditions.
