Numerical modeling of the global changes to the thermosphere and ionosphere from the dissipation of gravity waves from deep convection. Issue 9 (15th September 2014)

• Record Type: Journal Article
• Authors: Vadas, S. L.; Liu, H.‐L.; Lieberman, R. S.
• Is Part Of: Journal of geophysical research. Volume 119:Issue 9(2014:Sep.)
• Page Start: 7762
• Page End: 7793
• Publication Date: 2014-09-15
• Subjects: Magnetospheric physics -- Periodicals; Space environment -- Periodicals; Cosmic physics -- Periodicals; Planets -- Atmospheres -- Periodicals; Heliosphere (Astrophysics) -- Periodicals; Geophysics -- Periodicals; 523.01
• DOI: 10.1002/2014JA020280
• Languages: English
• ISSNs: 2169-9380

Abstract

<abstract abstract-type="main" id="jgra51217-abs-0001"> <title>Abstract</title> <p id="jgra51217-para-0001">During the minimum of solar cycles 23–24, the Sun was extremely quiet; however, tropospheric deep convection was strong and active. In this paper, we model the gravity waves (GWs) excited by deep convective plumes globally during 15–27 June in 2009 and in 2000 (previous solar maximum). We ray trace the GWs into the thermosphere and calculate the body force/heatings which result where they dissipate. We input these force/heatings into a global dynamical model and study the neutral and plasma changes that result. The body forces induce horizontal wind (<inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh3m4bs53n" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="block" altimg="urn:x-wiley:jgra:media:jgra51217:jgra51217-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mi>u</mml:mi></mml:mrow><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mi>′</mml:mi></mml:mrow></mml:msubsup></mml:math></alternatives></inline-formula>) and temperature (<italic>T</italic><sup>′</sup>) perturbations, while the heatings primarily induce <italic>T</italic><sup>′</sup>. We find that the forces create much larger <italic>T</italic><sup>′</sup> than the heatings. <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh3m4bs4zx" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="block" altimg="urn:x-wiley:jgra:media:jgra51217:jgra51217-math-0002" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mi>u</mml:mi></mml:mrow><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mi>′</mml:mi></mml:mrow></mml:msubsup></mml:math></alternatives></inline-formula> consists of clockwise and counterclockwise circulations and "jet"‐like winds that are highly correlated with deep convection, with <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh3m4bs500" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="block" altimg="urn:x-wiley:jgra:media:jgra51217:jgra51217-math-0003" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mo>|</mml:mo><mml:msubsup><mml:mrow><mml:mi>u</mml:mi></mml:mrow><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mi>′</mml:mi></mml:mrow></mml:msubsup><mml:mo>|</mml:mo></mml:math></alternatives></inline-formula>∼50–200m/s. <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh3m4bs4kv" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="block" altimg="urn:x-wiley:jgra:media:jgra51217:jgra51217-math-0004" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mi>u</mml:mi></mml:mrow><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mi>′</mml:mi></mml:mrow></mml:msubsup></mml:math></alternatives></inline-formula> and <italic>T</italic><sup>′</sup> are much larger during 2009 than 2000. <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh3m4bs4g6" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="block" altimg="urn:x-wiley:jgra:media:jgra51217:jgra51217-math-0005" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mrow><mml:mi>u</mml:mi></mml:mrow><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mi>′</mml:mi></mml:mrow></mml:msubsup></mml:math></alternatives></inline-formula> decreases slightly (significantly) with altitude from <italic>z</italic>∼150 to 400 km during 2009 (2000). <italic>T</italic><sup>′</sup> perturbations at <italic>z</italic>=350km primarily propagate westward at ∼460 m/s, consistent with migrating tides. It was found that planetary‐scale diurnal and semidiurnal tides are generated in situ in the thermosphere, with amplitudes ∼10–40m/s at <italic>z</italic>=250 km. The largest‐amplitude in situ tides are DW1, D0, DW2, SW2, SW3, and SW5. Smaller‐amplitude in situ tides are S0, SE2, and SW3. Total electron content (TEC<sup>′</sup>) perturbations of 1–2.5 (2–3.5) total electron content units (TECU, where 1 TECU = 10<sup>16</sup> el m<sup>−2</sup>) during 2009 (2000) are created in the upper atmosphere above nearby regions of deep tropical convection. For a given local time (LT), there are 2 to 3 TEC<sup>′</sup> peaks in longitude around the Earth.</p> </abstract>