We operate a network of ground-based ionospheric imaging systems. Current locations include Hawaii, Tahiti, Chile, Brazil, and Morocco. These images provide detailed information on the spatial distribution of plasma in the ionosphere. Under the correct geophysical conditions, irregularities in the ionosphere, known as equatorial plasma bubbles (EPBs), can form in the nighttime ionosphere. EPBs are easily imaged by these ground-based sensors (e.g., Makela and Miller, 2011; Makela et al., 2010; Makela, 2006) and have been shown to coexist with regions of the ionosphere that cause scintillations on trans-ionospheric radio signals (e.g., Miller and Makela, 2008; Ledvina and Makela, 2005), causing these radio links to be unusable. Thus, being able to image and characterize these regions is of primary importance to ensure reliable communication and navigation channels.

In this project, we utilize data collected by this network of imagers to study the properties of EPBs and participate in the Defense Meteorological Satellite Program (DMSP) CalVal effort by validating the ability of the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) on the DMSP vehicles to observe EPBs. Preliminary work (Kelley et al., 2003) comparing ground-based images and the precursor instrument to SSUSI (the Global Ultraviolet Imager on NASA’s Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics satellite) are shown in the figure and demonstrate the ability of the ground-based imager to validate the space-based observations.