CIPS Gravity Wave Analysis

Noctilucent clouds, also called polar mesospheric clouds (PMCs), one of the most unique visible events that occur in the upper atmosphere, require very specific conditions under which these clouds can form. Because of this, PMCs are extremely sensitive to the local environmental conditions, especially atmospheric gravity waves. The tenuous nature of PMCs allows for any gravity waves propagating through the layer to be easily identified, offering the opportunity to observe and characterize the gravity waves visible in Cloud Imaging and Particle Size (CIPS) data. With gravity waves being the main driver of circulation in the mesosphere, the classification and analyses of the wave motion is especially important if a complete understanding of the meridional circulation in the mesosphere is to be desired. The goal of the ongoing research presented in this paper is to empirically classify the wave variance present in images provided by NASA’s Aeronomy of Ice in the Mesosphere (AIM) satellite using CIPS images. It has been found, when using two days of data as the statistical set, i.e., Julian days 194 and 211 in 2007 (30 orbits total), both of which contain concentric wave events, that the along-orbit extension of a 20-60 km wave packet will most likely reside between 900-1000 km. Additionally, it was found that a higher fraction of wave structures possess lower albedo power corresponding to a smaller wave amplitude.