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Dear CEDAR community,
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<div>We invite you to attend and participate in the workshop entitled “Gravity wave multi-step vertical coupling from the troposphere to the thermosphere/ionosphere” at the 2021 CEDAR Workshop on June 23, Wednesday at 10 AM - 12 PM Mountain Time. We solicit
participation and short presentations (via Zoom) for this session.</div>
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<div>One of the challenges the aeronomy community has encountered recently is that it has become apparent that to accurately describe and model F region gravity waves, multi step vertical coupling needs to be included. This is true in both the winter and summer
hemispheres, but especially in the winter hemisphere. For the physical process of multi step vertical coupling, gravity wave dissipation leads to the creation of local body forces (i.e., horizontal accelerations) and heatings, both of which excite secondary
GWs. Where the secondary GWs dissipate, another set of GWs is excited (tertiary GWs), and so on to higher orders. Recent modeling has shown that this is the reason for the TAD hotspot in GOCE and CHAMP satellite density perturbations over the Southern Andes.
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<div>Session description:</div>
<div>We explore gravity wave excitation, propagation, dissipation, and re-excitation (following dissipation) at all altitudes from the lower to upper atmosphere and ionosphere. Studies can be at low, middle or high latitudes, and can be based on models, observationss,
or a combination of both. For example, fishbone structures showing evidence of secondary GWs in z-t plots can be analyzed and studied. Examples of the GWs from primary sources we include here are the generation of GWs from 1) orographic forcing, moist convection,
fronts, and jets in the troposphere, and 2) the polar vortex in the stratosphere. We emphasize the effects of these sources on the thermosphere/ionosphere (TI) via the generation of secondary and higher-order GWs (multi-step vertical coupling).</div>
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<div>Please send your name, title, a short description of your talk, and your desired presentation length to the conveners by Sunday, June 20.</div>
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<div>Thank you!</div>
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<div>Sharon Vadas (vasha@nwra.com)</div>
<div>Erich Becker (erich.becker@nwra.com)</div>
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