Bibliography

The International Reference Ionosphere 2012--a model of international collaboration

Bilitza, Dieter; Altadill, David; Zhang, Yongliang; Mertens, Chris; Truhlik, Vladimir; Richards, Phil; McKinnell, Lee-Anne; Reinisch, Bodo;

Published by: Journal of Space Weather and Space Climate      Published on:

YEAR: 2014     DOI:

Empirical STORM-E model: II. Geomagnetic corrections to nighttime ionospheric E-region electron densities

Auroral nighttime infrared emission observed by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument onboard the Thermosphere\textendashIonosphere\textendashMesosphere Energetics and Dynamics (TIMED) satellite is used to develop an empirical model of geomagnetic storm enhancements to E-region electron densities. The empirical model is called STORM-E and will be incorporated into the 2012 release of the International Reference Ionosphere (IRI). The proxy for characterizing the E-region response to geomagnetic forcing is NO⁺(v) Volume Emission Rates (VER) derived from the TIMED/SABER 4.3\ μm channel limb radiance measurements. The storm-time response of the NO⁺(v) 4.3\ μm VER is most sensitive to auroral particle precipitation. A statistical database of storm-time to climatological quiet-time ratios of SABER-observed NO⁺(v) 4.3\ μm VER are fit to widely available geomagnetic indices using the theoretical framework of linear impulse-response theory. The STORM-E model provides a dynamic storm-time correction factor to adjust a known nighttime quiescent E-region electron density peak concentration for geomagnetic enhancements due to auroral particle precipitation. Part I of this series gives a detailed description of the algorithms and methodologies used to derive NO⁺(v) VER from SABER 4.3\ μm limb emission measurements. In this paper, Part II of the series, the development of the E-region electron density storm-time correction factor is described. The STORM-E storm-time correction factor is fit to a single geomagnetic index. There are four versions of the STORM-E model, which are currently independent of magnetic local time. Each version is fit to one of the following indices: HP, AE, Ap, or Dst. High-latitude Incoherent Scatter Radar (ISR) E-region electron density measurements are compared to STORM-E predictions for various geomagnetic storm periods during solar cycle 23. These comparisons show that STORM-E significantly improves the prediction of E-region electron density enhancements due to auroral particle precipitation, in comparison to the nominal IRI model or to the quiet-time baseline electron density concentrations measured by ISR. The STORM-E/ISR comparisons indicate that the STORM-E fits to the Ap-, AE-, and HP-indices are comparable in both absolute accuracy and relative dynamical response. Contrarily, the Dst-index does not appear to be a suitable input driver to parameterize the E-region electron density response to geomagnetic activity.

Mertens, Christopher; Xu, Xiaojing; Bilitza, Dieter; Mlynczak, Martin; Russell, James;

Published by: Advances in Space Research      Published on: 02/2013

YEAR: 2013     DOI: 10.1016/j.asr.2012.09.014

AURORA; Auroral particle precipitation; E-region; Infrared remote sensing; Ionosphere; Magnetic storm; TIMED

Empirical STORM-E model: I. Theoretical and observational basis

Auroral nighttime infrared emission observed by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument onboard the Thermosphere–Ionosphere–Mesosphere Energetics and Dynamics (TIMED) satellite is used to develop an empirical model of geomagnetic storm enhancements to E-region peak electron densities. The empirical model is called STORM-E and will be incorporated into the 2012 release of the International Reference Ionosphere (IRI). The proxy for characterizing the E-region response to geomagnetic forcing is NO+(v) volume emission rates (VER) derived from the TIMED/SABER 4.3μm channel limb radiance measurements. The storm-time response of the NO+(v) 4.3μm VER is sensitive to auroral particle precipitation. A statistical database of storm-time to climatological quiet-time ratios of SABER-observed NO+(v) 4.3μm VER are fit to widely available geomagnetic indices using the theoretical framework of linear impulse-response theory. The STORM-E model provides a dynamic storm-time correction factor to adjust a known quiescent E-region electron density peak concentration for geomagnetic enhancements due to auroral particle precipitation. Part II of this series describes the explicit development of the empirical storm-time correction factor for E-region peak electron densities, and shows comparisons of E-region electron densities between STORM-E predictions and incoherent scatter radar measurements. In this paper, Part I of the series, the efficacy of using SABER-derived NO+(v) VER as a proxy for the E-region response to solar-geomagnetic disturbances is presented. Furthermore, a detailed description of the algorithms and methodologies used to derive NO+(v) VER from SABER 4.3μm limb emission measurements is given. Finally, an assessment of key uncertainties in retrieving NO+(v) VER is presented.

Mertens, Christopher; Xu, Xiaojing; Bilitza, Dieter; Mlynczak, Martin; Russell, James;

Published by: Advances in Space Research      Published on:

YEAR: 2013     DOI: https://doi.org/10.1016/j.asr.2012.09.009

Auroral particle precipitation; Ionosphere; E-region; Magnetic storm; Infrared remote sensing; SABER

The Storm Time Energy and Dynamics Explorers

Swenson, C; Fish, CS; Crowley, G; Earle, GD; Anderson, BJ; Dyrud, LP; Carlson, HC; Erickson, PJ; Fejer, BG; Mertens, CJ; , others;

Published by:       Published on:

YEAR: 2011     DOI:

Ionospheric E-Region Chemistry and Energetics

Mertens, Christopher; Mlynczak, Martin; Gronoff, Guillaume; Yee, Jeng-Hwa; Swenson, Charles; Fish, Chad; Wellard, Stan; Lumpe, Jerry; Strickland, Doug; Evans, Scott;

Published by: To propose an Earth-observing, multi-satellite science mission to explore the last remaining frontier in upper atmospheric research—the ionospheric E-region      Published on:

YEAR: 2010     DOI:

Influence of solar-geomagnetic disturbances on SABER measurements of 4.3 Micrometer emission and the retrieval of kinetic temperature and carbon dioxide

Thermospheric infrared radiance at 4.3 μm is susceptible to the influence of solar-geomagnetic disturbances. Ionization processes followed by ion-neutral chemical reactions lead to vibrationally excited NO+ (i.e., NO+(v)) and subsequent 4.3 μm emission in the ionospheric E-region. Large enhancements of nighttime 4.3 μm emission were observed by the TIMED/SABER instrument during the April 2002 and October\textendashNovember 2003 solar storms. Global measurements of infrared 4.3 μm emission provide an excellent proxy to observe the nighttime E-region response to auroral dosing and to conduct a detailed study of E-region ion-neutral chemistry and energy transfer mechanisms. Furthermore, we find that photoionization processes followed by ion-neutral reactions during quiescent, daytime conditions increase the NO+ concentration enough to introduce biases in the TIMED/SABER operational processing of kinetic temperature and CO2 data, with the largest effect at summer solstice. In this paper, we discuss solar storm enhancements of 4.3 μm emission observed from SABER and assess the impact of NO+(v) 4.3 μm emission on quiescent, daytime retrievals of Tk/CO2 from the SABER instrument.

Mertens, Christopher; Winick, Jeremy; Picard, Richard; Evans, David; opez-Puertas, Manuel; Wintersteiner, Peter; Xu, Xiaojing; Mlynczak, Martin; Russell, James;

Published by: Advances in Space Research      Published on:

YEAR: 2009     DOI: 10.1016/j.asr.2008.10.029

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

Ionospheric E-region response to solar-geomagnetic storms observed by TIMED/SABER and application to IRI storm-model development

The large thermospheric infrared radiance enhancements observed from the TIMED/SABER experiment during recent solar storms provide an exciting opportunity to study the influence of solar-geomagnetic disturbances on the upper atmosphere and ionosphere. In particular, nighttime enhancements of 4.3μm emission, due to vibrational excitation and radiative emission by NO+, provide an excellent proxy to study and analyze the response of the ionospheric E-region to auroral electron dosing and storm-time enhancements to the E-region electron density. In this paper, we give a status report of on-going work on model and data analysis methodologies of deriving NO+ 4.3μm volume emission rates, a proxy for the storm-time E-region response, and the approach for deriving an empirical storm-time correction to IRI E-region NO+ and electron densities.

Mertens, Christopher; Mast, Jeffrey; Winick, Jeremy; Russell, James; Mlynczak, Martin; Evans, David;

Published by: Advances in Space Research      Published on:

YEAR: 2007     DOI: https://doi.org/10.1016/j.asr.2006.09.032

Ionosphere; Magnetic storms; Ion-neutral chemistry; Non-LTE; Radiation transfer

Energy transport in the thermosphere during the solar storms of April 2002

Mlynczak, Martin; Martin-Torres, Javier; Crowley, Geoff; Kratz, David; Funke, Bernd; Lu, Gang; Lopez-Puertas, Manuel; Russell, James; Kozyra, Janet; Mertens, Chris; Sharma, Ramesh; Gordley, Larry; Picard, Richard; Winick, Jeremy; Paxton, L.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2005

YEAR: 2005     DOI: 10.1029/2005JA011141

Influence of geomagnetic-ionospheric disturbances on SABER measurements of 4.3 um emission and the retrievals of kinetic temperature and carbon dioxide

Mertens, CJ; Richards, PG; , Winick; Picard, RH; Paxton, LJ; Wintersteiner, PP; Team, Saber;

Published by:       Published on:

YEAR: 2004     DOI:

The natural thermostat of nitric oxide emission at 5.3 μm in the thermosphere observed during the solar storms of April 2002

The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiment on the Thermosphere-Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite observed the infrared radiative response of the thermosphere to the solar storm events of April 2002. Large radiance enhancements were observed at 5.3 μm, which are due to emission from the vibration-rotation bands of nitric oxide (NO). The emission by NO is indicative of the conversion of solar energy to infrared radiation within the atmosphere and represents a \textquotedblleftnatural thermostat\textquotedblright by which heat and energy are efficiently lost from the thermosphere to space and to the lower atmosphere. We describe the SABER observations at 5.3 μm and their interpretation in terms of energy loss. The infrared enhancements remain only for a few days, indicating that such perturbations to the thermospheric state, while dramatic, are short-lived.

Mlynczak, Marty; Martin-Torres, F.; Russell, J.; Beaumont, K.; Jacobson, S.; Kozyra, J.; opez-Puertas, M.; Funke, B.; Mertens, C.; Gordley, L.; Picard, R.; Winick, J.; Wintersteiner, P.; Paxton, L.;

Published by: Geophysical Research Letters      Published on: 03/2003

YEAR: 2003     DOI: 10.1029/2003GL017693

The natural thermostat of nitric oxide emission at 5.3 $\mu$m in the thermosphere observed during the solar storms of April 2002

Mlynczak, Marty; Martin-Torres, Javier; Russell, James; Beaumont, Ken; Jacobson, Steven; Kozyra, Janet; Lopez-Puertas, Manuel; Funke, Bernd; Mertens, Christopher; Gordley, Larry; , others;

Published by: Geophysical Research Letters      Published on:

YEAR: 2003     DOI:

Analysis of the energy input and loss in the thermosphere during the auroral events using SABER infrared limb emission and GUVI limb emission

, Winick; Mlynczak, MG; Wintersteiner, PP; Martin-Torres, F; Picard, RH; Paxton, L; Lopez-Puertas, M; Mertens, CJ; RUSSELL, JM; Christensen, A; , others;

Published by:       Published on:

YEAR: 2003     DOI: