Search Results - "Emmert, J. T."

Altitude and solar activity dependence of 1967-2005 thermospheric density trends derived from orbital drag by Emmert, J. T.

“…We examine 1967–2005 thermospheric mass density trends (as well as 1967–2013 trends) derived from satellite orbit data, as a function of altitude, solar flux,…”
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Record-low thermospheric density during the 2008 solar minimum by Emmert, J. T., Lean, J. L., Picone, J. M.

“…We use global‐average thermospheric total mass density, derived from the drag effect on the orbits of many space objects, to study the behavior of the…”
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Climatology of globally averaged thermospheric mass density by Emmert, J. T., Picone, J. M.

“…We present a climatological analysis of daily globally averaged density data, derived from orbit data and covering the years 1967–2007, along with an empirical…”
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NRLMSIS 2.0: A Whole‐Atmosphere Empirical Model of Temperature and Neutral Species Densities by Emmert, J. T., Drob, D. P., Picone, J. M., Siskind, D. E., Jones, M., Mlynczak, M. G., Bernath, P. F., Chu, X., Doornbos, E., Funke, B., Goncharenko, L. P., Hervig, M. E., Schwartz, M. J., Sheese, P. E., Vargas, F., Williams, B. P., Yuan, T.

“…NRLMSIS® 2.0 is an empirical atmospheric model that extends from the ground to the exobase and describes the average observed behavior of temperature, eight…”
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A computationally compact representation of Magnetic-Apex and Quasi-Dipole coordinates with smooth base vectors by Emmert, J. T., Richmond, A. D., Drob, D. P.

“…Many structural and dynamical features of the ionized and neutral upper atmosphere are strongly organized by the geomagnetic field, and several magnetic…”
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A long-term data set of globally averaged thermospheric total mass density by Emmert, J. T.

“…We present a long‐term data set, available on the CEDAR Data System, of globally averaged thermospheric total mass density derived from the orbits of ∼5000…”
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Attribution of interminimum changes in global and hemispheric total electron content by Emmert, J. T., Mannucci, A. J., McDonald, S. E., Vergados, P.

“…We use a new data product of electron column density (total electron content, or TEC) maps to estimate and attribute the interminimum changes (the differences…”
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Thermospheric global average density trends, 1967–2007, derived from orbits of 5000 near-Earth objects by Emmert, J. T., Picone, J. M., Meier, R. R.

“…We use orbit data on ∼5000 near‐Earth space objects to investigate long‐term trends in thermospheric total mass density, which has been predicted to decrease…”
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An empirical model of the Earth's horizontal wind fields: HWM07 by Drob, D. P., Emmert, J. T., Crowley, G., Picone, J. M., Shepherd, G. G., Skinner, W., Hays, P., Niciejewski, R. J., Larsen, M., She, C. Y., Meriwether, J. W., Hernandez, G., Jarvis, M. J., Sipler, D. P., Tepley, C. A., O'Brien, M. S., Bowman, J. R., Wu, Q., Murayama, Y., Kawamura, S., Reid, I. M., Vincent, R. A.

“…The new Horizontal Wind Model (HWM07) provides a statistical representation of the horizontal wind fields of the Earth's atmosphere from the ground to the…”
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Ionospheric total electron content: Spatial patterns of variability by Lean, J. L., Meier, R. R., Picone, J. M., Sassi, F., Emmert, J. T., Richards, P. G.

“…The distinctive spatial patterns of the ionosphere's total electron content (TEC) response to solar, seasonal, diurnal, and geomagnetic influences are…”
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Coupling From the Middle Atmosphere to the Exobase: Dynamical Disturbance Effects on Light Chemical Species by Jones, M., Siskind, D. E., Drob, D. P., McCormack, J. P., Emmert, J. T., Dhadly, M. S., Attard, H. E., Mlynczak, M. G., Brown, P. G., Stober, G., Kozlovsky, A., Lester, M., Jacobi, C.

“…This paper characterizes the impacts of sudden stratospheric warmings (SSWs) and mesospheric coolings (MCs) on the light species distribution (i.e., helium…”
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Attribution of interminima changes in the global thermosphere and ionosphere by Emmert, J. T., McDonald, S. E., Drob, D. P., Meier, R. R., Lean, J. L., Picone, J. M.

“…We present a statistical attribution analysis of the changes in global annual average thermospheric mass density and ionospheric total electron content (TEC)…”
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Observations of increasing carbon dioxide concentration in Earth’s thermosphere by Emmert, J. T., Stevens, M. H., Bernath, P. F., Drob, D. P., Boone, C. D.

“…Above an altitude of about 50 km, carbon dioxide is the primary radiative cooling agent. Carbon dioxide and carbon monoxide mixing ratios derived from…”
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DWM07 global empirical model of upper thermospheric storm-induced disturbance winds by Emmert, J. T., Drob, D. P., Shepherd, G. G., Hernandez, G., Jarvis, M. J., Meriwether, J. W., Niciejewski, R. J., Sipler, D. P., Tepley, C. A.

“…We present a global empirical disturbance wind model (DWM07) that represents average geospace‐storm‐induced perturbations of upper thermospheric (200–600 km…”
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Theoretical tools for studies of low-frequency thermospheric variability by Picone, J. M., Meier, R. R., Emmert, J. T.

“…This paper supports studies of low‐frequency variability (LFV) within the thermosphere by deriving approximate integral and closed‐form solutions of a…”
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Thermospheric mass density: A review by Emmert, J.T.

“…The mass density of Earth’s thermosphere (∼90–600km altitude) is a critical parameter for low Earth orbit prediction because of the atmospheric drag on…”
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Remote Sensing of Earth's Limb by TIMED/GUVI: Retrieval of thermospheric composition and temperature by Meier, R. R., Picone, J. M., Drob, D., Bishop, J., Emmert, J. T., Lean, J. L., Stephan, A. W., Strickland, D. J., Christensen, A. B., Paxton, L. J., Morrison, D., Kil, H., Wolven, B., Woods, Thomas N., Crowley, G., Gibson, S. T.

“…The Global Ultraviolet Imager (GUVI) onboard the Thermosphere‐Ionosphere‐Mesosphere Energetics and Dynamics (TIMED) satellite senses far ultraviolet emissions…”
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Global change in the thermosphere: Compelling evidence of a secular decrease in density by Emmert, J. T., Picone, J. M., Lean, J. L., Knowles, S. H.

“…We derive secular trends in upper thermospheric density from the historical orbital elements of 27 long‐lived, near‐Earth space objects. The results cover all…”
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Emerging pattern of global change in the upper atmosphere and ionosphere by Laštovička, J., Akmaev, R. A., Beig, G., Bremer, J., Emmert, J. T., Jacobi, C., Jarvis, M. J., Nedoluha, G., Portnyagin, Yu. I., Ulich, T.

“…In the upper atmosphere, greenhouse gases produce a cooling effect, instead of a warming effect. Increases in greenhouse gas concentrations are expected to…”
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Low-latitude ionospheric disturbance electric field effects during the recovery phase of the 19–21 October 1998 magnetic storm by Fejer, B. G., Emmert, J. T.

“…Low‐latitude ionospheric electric fields and currents are often strongly disturbed during periods of enhanced geomagnetic activity. These perturbations can…”
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