Wave-Wave Interactions and Upper Atmosphere Variability

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

Large-scale vertically-propagating waves such as planetary waves (PW) and tidal waves (TW) represent the primary means by which energy from lower atmosphere meteorological activity is transmitted into the upper atmosphere region. The coupling interaction between these waves is believed to be a source of strong variability that is transmitted into the upper atmosphere and ionosphere as secondary wave structures that could potentially affect navigation, communications and radar tracking systems. Understanding the origins of such variability in the mesosphere and lower thermosphere (MLT) region is one of the major challenges faced in space physics. This award would focus on studying these large-scale wave interactions and the secondary waves they produce by using a year-long dataset generated by the use of a NCAR general circulation model (TIME-GCM), coupled to the use of the Global Scale Wave Model (GSWM) that would provide simulations of the lower atmosphere inputs into the upper atmosphere model. The broader impacts of the research effort will be realized in several different ways: (a) engagement with a diverse population of students through partnership with the Broadening Opportunity through Leadership and Diversity (BOLD) Center; (b) engaging an undergraduate student in the research through the Discovery Learning Apprentice (DLA) Program; (c) leveraging the above connections to teach graduate students how to mentor. For individual cases where non-linear interactions are seen, a non-linear version of the GSWM model will be employed to perform numerical experiments, investigating factors such as how the phases of the two primary waves impact the generation of the secondary waves. The primary objectives of the work are as follows: 1) to delineate and understand the basic mechanisms underlying the interactions between PWs and tides propagating up from the lower atmosphere, 2) to quantify the variability imposed on the global atmosphere-ionosphere system by these interactions, and 3) to assess the implications for ground-based and space-based observing systems.