Advancing our understanding of the atmosphere and ionosphere using remote sensing techniques

Many human activities affect or are affected by physical and chemical, proc esses occurring in the Earth's atmosphere, ionosphere, and near-Earth space environment. In this article, we review a wide range of remote sensing res earch activities being carried out within the APL Space Department that hav e provided a better understanding of these processes. The research, conduct ed from both the ground and satellites, includes techniques employing optic al remote, radar remote, and particle remote sensing, We concentrate on the scientific accomplishments of these efforts with particular emphasis on co ntributions to atmospheric, ionospheric, and magnetospheric research.