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Dear colleagues:</div>
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I would like to draw your attention to the Grand Challenge Workshop: <span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" class="ContentPasted1">The
role of gravity waves in the mesosphere, thermosphere and ionosphere cross-scale coupling and irregularities: Observations and numerical simulations, during the upcoming CEDAR meeting this June.</span></div>
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<span style="font-size:12.0pt;font-family:"Times New Roman",serif" class="ContentPasted2">Contributions to the upper atmospheric dynamics and the ionospheric irregularities by the ubiquitous gravity waves’ modulations with various scales have been recognized
and studied intensively over the past decades. The associated dynamical features, such as Kelvin-Helmholtz Instability (KHI), can further induce considerable variations in this region. Their horizontal scales have been found to vary from around a few tens
of km to several thousand kilometers. The impacts of small-scale features, frequently observed in the mesosphere and lower thermosphere, are believed to be as significant as those of larger scale waves in the thermosphere and ionosphere, because of their fast
phase speeds and the high momentum density they are carrying. The dynamical behaviors under atmospheric instability conditions, changing the laminar flow to turbulence flow, are especially important and enticing, when the energy and momentum transfer between
them and the mean flow occurs, altering larger-scale dynamic features and potentially triggering some of the most significant ionospheric irregularities.
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<span style="font-size:12.0pt;font-family:"Times New Roman",serif" class="ContentPasted2">Various state-of-art ground-based, airborne and space borne experimental investigations have been dedicated to the investigations on this topic in the past decade, facilitated
by many advanced regional and global numerical models. While considerable progress in understanding their contributions to the energy and momentum budget in the thermosphere ionosphere have been achieved, more and more unknown physics and dynamic processes
have also been revealed in these observations. In addition, the lack of global coverage, and the limited observed gravity wave spectrum further limit the community’s progress in the understanding of the Ionosphere-Thermosphere (IT) gravity wave coupling.<o:p class="ContentPasted2"> </o:p></span></p>
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<span style="font-size:12.0pt;font-family:"Times New Roman",serif" class="ContentPasted2">In this workshop, we will discuss the gaps, challenging problems and coordinated approaches of addressing the role of gravity waves in the mesosphere, thermosphere and
ionosphere coupling.<o:p class="ContentPasted2"> The workshop will<span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" class="ContentPasted3"> provide
a community-wide platform for open discussions on the new coordinated investigations and campaigns to improve the understanding of these waves full contributions to the global IT system.</span></o:p></span></p>
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Hope to see you all in San Diego.</p>
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Best,</div>
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<span style="font-weight:normal"><font face="Helvetica Neue, Helvetica, Arial, sans-serif" style="color: rgb(56, 70, 96);"><span style="font-size:12pt">Titus Yuan</span></font><font face="Helvetica Neue, Helvetica, Arial, sans-serif" style="color: rgb(56, 70, 96);"><span style="font-size:14px"><br>
</span></font><span style="font-size:12pt">Assistant Professor</span><br>
<span style="font-size:12pt">Physics Department</span><br>
<span style="font-size:12pt">Utah State University</span><br>
<span style="font-size:12pt">Logan, UT 84322</span><br>
<span style="font-size:12pt">(435)-232-2534</span></span><br>
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