Bibliography

The quasi-6~day wave and its interactions with solar tides

Thermosphere Ionosphere Mesosphere Energetics and Dynamics/Sounding of the Atmosphere using Broadband Emission Radiometry (TIMED/SABER) temperature measurements between 20 and 110\ km altitude and \textpm50\textdegree latitude during 2002\textendash2015 are employed to reveal the climatological characteristics of the quasi-6\ day wave (Q6DW) and evidence for secondary waves (SW) resulting from its nonlinear interactions with solar tides. The mean period is 6.14d with a standard deviation (σ) of 0.26d. Multiyear-mean maximum amplitudes (3\textendash5\ K, σ \~ 4\ K) occur within the mesosphere-lower thermosphere (MLT) region between 75 and 100\ km during day of year (DOY) 60\textendash120 and 180\textendash300 in the Northern Hemisphere and DOY 0\textendash110 and 200\textendash300 in the Southern Hemisphere. Amplitudes approach 10\ K in some individual years. At midlatitudes downward phase progression exists from 100 to 35\ km with a mean vertical wavelength of about 70\ km. Signatures of SW due to Q6DW-tide interactions appear at distinct space-based zonal wave numbers (k_s) in temperature spectra constructed in the reference frame of the TIMED orbit. However, SW produced by several different tides can collapse onto the same (k_s) value, rendering their relative contributions indistinguishable. Nevertheless, by determining the space-based wave amplitudes attached to these values of (k_s), and demonstrating that they are a large fraction of the interacting wave amplitudes, we conclude that the aggregate contributions of the SW to the overall wave spectrum must be significant. Because the SW have periods, zonal wave numbers, and latitude-height structures different from those of the primary waves, they contribute additionally to the complexity of the wave spectrum. This complexity is communicated to the ionosphere through collisions or through the dynamo electric fields generated by the total wave spectrum.

Forbes, Jeffrey; Zhang, Xiaoli;

Published by: Journal of Geophysical Research: Space Physics      Published on: 03/2017

YEAR: 2017     DOI: 10.1002/2017JA023954

The quasi-6 day wave and its interactions with solar tides

Q6DW in the lower thermosphere; the [O]/[N 2 ] variations were measured by Thermosphere Ionosphere Mesosphere Energetics and Dynamics/Global Ultraviolet Imager (TIMED/GUVI)

Forbes, Jeffrey; Zhang, Xiaoli;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2017     DOI: 10.1002/2017JA023954

Ionosphere response to recurrent geomagnetic activity in 1974

Fang, Tzu-Wei; Forbes, Jeffrey;

Published by: Journal of Geophysical Research      Published on: Jan-01-2012

YEAR: 2012     DOI: 10.1029/2011JA017017

Wave-driven variability in the ionosphere-thermosphere-mesosphere system from TIMED observations: What contributes to the "wave 4"?

Oberheide, J.; Forbes, J.; Zhang, X.; Bruinsma, S.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2011

YEAR: 2011     DOI: 10.1029/2010JA015911

Ionosphere response to recurrent geomagnetic activity: Local time dependency

Pedatella, N.; Lei, J.; Thayer, J.; Forbes, J.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2010

YEAR: 2010     DOI: 10.1029/2009JA014712

The Armada mission: Determining the dynamic and spatial response of the thermosphere/ionosphere system to energy inputs on global and regional scales

Ridley, AJ; Forbes, JM; Cutler, J; Nicholas, AC; Thayer, JP; Fuller-Rowell, TJ; Matsuo, T; Bristow, WA; Conde, MG; Drob, DP; , others;

Published by:       Published on:

YEAR: 2010     DOI:

The effect of non-migrating tides on the morphology of the equatorial ionospheric anomaly: seasonal variability

England, Scott; Zhang, Xiaoli; Immel, Thomas; Forbes, Jeffrey; DeMajistre, Robert;

Published by: Earth Planets Space      Published on:

YEAR: 2009     DOI:

Upward propagating tidal effects across the E-and F-regions of the ionosphere

Immel, Thomas; England, Scott; Zhang, Xiaoli; Forbes, Jeffrey; DeMajistre, Robert;

Published by: Earth, planets and space      Published on:

YEAR: 2009     DOI:

LONGITUDINAL VARIATION OF THE ANNUAL AND HEMISPHERIC ASYMMETRIES OF THE LOW-MIDDLE LATITUDE IONOSPHERE

Kwak, Y; Kil, H; Oh, S; Lee, W; Forbes, JM; Cho, K;

Published by:       Published on:

YEAR: 2009     DOI:

Observations of the ionospheric response to the 15 December 2006 geomagnetic storm: Long-duration positive storm effect

The long-duration positive ionospheric storm effect that occurred on 15 December 2006 is investigated using a combination of ground-based Global Positioning System (GPS) total electron content (TEC), TOPEX and Jason-1 TEC, and topside ionosphere/plasmasphere TEC, GPS radio occultation, and tiny ionospheric photometer (TIP) observations from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites. This multi-instrument approach provides a unique view of the ionospheric positive storm effect by revealing the storm time response in different altitude regions. The ground-based GPS TEC, TOPEX/Jason-1 TEC, and topside ionosphere/plasmasphere TEC all reveal significant enhancements at low latitudes to midlatitudes over the Pacific Ocean region during the initial portions of the storm main phase from 0000–0400 universal time (UT) on 15 December. At low latitudes, the topside ionosphere/plasmasphere TEC increase represents greater than 50\% of the TEC enhancement that is observed by ground-based GPS receivers. Moreover, electron density profiles obtained using the technique of GPS radio occultation demonstrate that the F layer peak height increased by greater than 100 km during this time period. The effects of soft particle precipitation are also apparent in the COSMIC observations of topside ionosphere/plasmasphere TEC. The positive storm effects over the Pacific Ocean region remain present in the equatorial ionization anomaly crest regions beyond 1200 UT on 15 December. This long-lasting positive storm effect is most apparent in ground-based GPS TEC and COSMIC TIP observations, while only a small increase in the topside ionosphere/plasmasphere TEC after 0400 UT is observed. This indicates that the long-lasting positive storm effect occurs predominantly at F region altitudes and, furthermore, that refilling of the topside ionosphere and plasmasphere is not the primary mechanism for producing the long-lasting positive storm phase during this event. The observations suggest that the enhanced eastward electric field and equatorward neutral wind are likely to play a significant role in the generation of long-lasting positive storm effects.

Pedatella, N.; Lei, J.; Larson, K.; Forbes, J.;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2009     DOI: https://doi.org/10.1029/2009JA014568

Ionosphere; geomagnetic storm

Reversed ionospheric convections during the November 2004 storm: Impact on the upper atmosphere

Using the Assimilative Mapping of Ionospheric Electrodynamics (AMIE) procedure, a particular period (2000–2350 UT on 9 November) in the November 2004 storm is studied. During this time interval, IMF Bz was strongly northward along with a high solar wind dynamic pressure, favorable conditions to form reversed convection in the polar region. Indeed, the AMIE outputs show strong reversed convection cells in both hemispheres for a long period (>1 h), which have rarely been observed. The impact on the thermospheric neutral wind has been investigated using the AMIE outputs as the electrodynamic inputs of the National Center for Atmospheric Research Thermosphere Ionosphere Electrodynamics General Circulation Model. After the ionospheric convection reversed, the neutral wind distribution at 400 km altitude changed correspondingly, and the difference wind patterns reversed in the polar cap region. By comparing the temporal variations of the difference ion convection and the difference neutral wind, it is found that horizontal neutral winds respond to the reversed convection with some time delay. The neutral wind response time (e-folding time) clearly has an altitudinal dependence varying from 45 min at 400 km altitude to almost 1.5 h at 200 km. The vertical component vorticity has a similar magnitude and distribution to previous studies in the northward Bz condition and changes the sign when the convection pattern is reversed. Comparison between the CHAMP observed cross-track wind and the simulated neutral wind exhibits a general agreement, and the temporal variations of CHAMP cross-track wind indicate a strong effect of the ion drag force on neutral winds.

Deng, Yue; Lu, Gang; Kwak, Young-Sil; Sutton, Eric; Forbes, Jeffrey; Solomon, Stan;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2009     DOI: https://doi.org/10.1029/2008JA013793

reversed convection; November 2004 storm

Tidal propagation of deep tropical cloud signatures into the thermosphere from TIMED observations

Oberheide, J.; Forbes, J.;

Published by: Geophysical Research Letters      Published on: Jan-01-2008

YEAR: 2008     DOI: 10.1029/2007GL032397

Neutral composition and density effects in the October-November 2003 Magnetic Storms

Immel, TJ; Crowley, Geoff; Forbes, JM; Nerem, RS; Sutton, EK;

Published by: Midlatitude Ionospheric Dynamics and Disturbances      Published on:

YEAR: 2008     DOI:

Rotating solar coronal holes and periodic modulation of the upper atmosphere

Lei, Jiuhou; Thayer, Jeffrey; Forbes, Jeffrey; Sutton, Eric; Nerem, Steven;

Published by: Geophysical Research Letters      Published on:

YEAR: 2008     DOI:

Tidal variability in the ionospheric dynamo region

The seasonal and interannual variability of migrating (Sun-synchronous) and nonmigrating solar atmospheric tides at altitudes between 100 and 116 km are investigated using temperature measurements made with the SABER instrument on the TIMED spacecraft during 2002–2006. Quasi-biennial variations of order ±10–15\% in migrating diurnal and semidiurnal tidal amplitudes are found, presumably due to modulation by the quasi-biennial oscillation (QBO) as the tides propagate from their troposphere and stratospheric sources to the lower thermosphere. A number of nonmigrating tidal components are found that have the potential to produce significant longitudinal variability of the total tidal fields. The most prominent of these, i.e., those that appear at amplitudes of order 5–10 K in a 5-year mean climatology, include the zonally symmetric (s = 0) diurnal tide (D0); the eastward propagating diurnal and semidiurnal tides with zonal wave numbers s = −2 (DE2 and SE2) and s = −3 (DE3 and SE3); and the following westward propagating waves: diurnal s = 2 (DW2); semidiurnal s = 1 (SW1), s = 3 (SW3), and s = 4 (SW4); and terdiurnal s = 5 (TW5). These waves can be plausibly accounted for by nonlinear interaction between migrating tidal components and stationary planetary waves with s = 1 or s = 2 or by longitudinal variations of tropospheric thermal forcing. Additional waves that occur during some years or undergo phase cancellation within construction of a 5-year climatology include DW5, SE1, SE4, SW6, TE1, TW1, and TW7. It is anticipated that the winds that accompany all of these waves in the 100–170 km region will impose longitudinal variability in the electric fields produced through the ionospheric dynamo mechanism, thereby modulating vertical motion of the equatorial ionosphere and the concomitant plasma densities. In addition to the wave-4 modulation of the equatorial ionosphere that has recently been discovered and replicated in modeling studies, the waves revealed here will generate wave-1 (SW1, SW3, D0, DW2), wave-2 (SW4, TW1), wave-3 (DE2, SE1), wave-4 (DE3, SE2, DW5, SW6, TE1, TW7), wave-5 (SE3), and wave-6 (SE4) components of this ionospheric variability, depending on year and time of year. However, the absolute and relative efficiencies with which these waves produce electric fields remains to be determined.

Forbes, J.; Zhang, X.; Palo, S.; Russell, J.; Mertens, C.; Mlynczak, M.;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2008     DOI: https://doi.org/10.1029/2007JA012737

tides; dynamo; Ionosphere

Density and winds in the thermosphere deduced from accelerometer data

IN THE past 10 years, the thermosphere community has called for a movement from station-based and regional studies to global studies spanning several decades [1–3]. Since these

Sutton, Eric; Nerem, Steven; Forbes, Jeffrey;

Published by: Journal of Spacecraft and Rockets      Published on:

YEAR: 2007     DOI: 10.2514/1.28641

Thermosphere density response to the 20\textendash21 November 2003 solar and geomagnetic storm from CHAMP and GRACE accelerometer data

Bruinsma, Sean; Forbes, Jeffrey; Nerem, Steven; Zhang, Xiaoli;

Published by: Journal of Geophysical Research      Published on: Jan-01-2006

YEAR: 2006     DOI: 10.1029/2005JA011284

Thermosphere density response to the 20-21 November 2003 solar and geomagnetic storm from CHAMP and GRACE accelerometer data

Bruinsma, Sean; Forbes, Jeffrey; Nerem, Steven; Zhang, Xiaoli;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2006     DOI:

NASA Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) Mission: Significant Findings and Evolving Research

Yee, J; Christensen, A; Russell, J; Killeen, T; Woods, T; Kozyra, J; Smith, A; Fritts, D; Forbes, J; Mayr, H; , others;

Published by:       Published on:

YEAR: 2005     DOI: