The high latitude plasma structure campaigns (HLPS) are aimed at the understanding of the general morphology of ionization structures that are observed in the high latitude polar cap thermosphere. Many of the different phenomena that are studied are solar cycle dependent with some of the key processes apparent only at solar maximum. Since the next few years are at the peak of one of the largest solar activity cycles a unique opportunity exists to study these phenomena with extensive coordinated observations at many different polar locations with many different diagnostic instruments. This proposed project will enable scientists to take full advantage of two recently installed modern digital ionosondes (Digisonde) at two remote locations in Greenland during HLPS campaigns in 1990 and 1991.
