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Dear CEDAR community,
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<div class="">We would like to invite you to participate in the <a href="http://cedarweb.vsp.ucar.edu/wiki/index.php/2021_Workshop:Terrestrial_Hydrogen" class="">CEDAR Terrestrial Hydrogen</a> workshop that will take place on Wednesday 6/23/21 from 10-noon
Mountain time. We still have room for additional presentations so please contact us if you would like to make a presentation. We look forward to seeing you and to hearing about your work. </div>
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<div class="">Thank you,</div>
<div class="">Best wishes,</div>
<div class="">Ed Mierkiewicz and Susan Nossal</div>
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<span class="mw-headline" id="Description">Description</span></h3>
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Evaluating the distribution of hydrogen in the Earth’s atmosphere, and how that distribution responds to external forcing factors (e.g., solar activity), is important to our understanding of the mechanisms that shape the evolution of planetary atmospheres.
Knowledge of this distribution can also guide atmospheric photochemical modeling of hydrogen containing species (e.g., CH4 and H2O), and be used for benchmark studies for these models. Further, hydrogen plays an important role in the mesosphere, thermosphere
and exosphere as well as being the dominant species in the topside ionosphere. Hydrogen is also an indicator of whether our understanding of the processes near the turbopause is correct; the limiting flux of H into the thermosphere is established by the effective
eddy mixing coefficient (Donahue, 1969). One of the most commonly used methods for investigating H from the ground is to use the H Balmer alpha line. Spacebased observations, such as those planned for the GLIDE and SIHLA mission, open new opportunities. Small
optical remote sensing instruments on cubesats, commercial suborbital flight or other platforms will provide other insights. In this session we solicit contributions from the modeling and the observational community to address our current understanding, identify
gaps / challenges, and establish a path forward. We look forward to contributions from across the entire spectrum of inquiry into hydrogen ranging from lower atmosphere exchange to plasmaspheric processes.</div>
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<div class="">Susan Nossal</div>
<div class="">Scientist & Director, Physics Learning Center</div>
<div class="">Physics Department</div>
<div class="">University of Wisconsin-Madison</div>
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<div class=""><a href="mailto:nossal@physics.wisc.edu" class="">nossal@physics.wisc.edu</a></div>
<div class="">she/her/hers</div>
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