Search Results - "Emmert, 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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Thermal versus acoustic response of velocity sensitive premixed flames by Bomberg, S., Emmert, T., Polifke, W.

“…Premixed flames respond to velocity perturbations with fluctuations in heat release rate ("thermal response"), which in turn generate acoustic perturbations…”
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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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Anomalously low solar extreme-ultraviolet irradiance and thermospheric density during solar minimum by Solomon, Stanley C., Woods, Thomas N., Didkovsky, Leonid V., Emmert, John T., Qian, Liying

“…Solar activity during 2007–2009 was very low, and during this protracted solar minimum period, the terrestrial thermosphere was cooler and lower in density…”
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Short‐Term and Interannual Variations of Migrating Diurnal and Semidiurnal Tides in the Mesosphere and Lower Thermosphere by Dhadly, Manbharat S., Emmert, John T., Drob, Douglas P., McCormack, John P., Niciejewski, Rick J.

“…Among the broad spectrum of vertically propagating tides, migrating diurnal (DW1) and semidiurnal (SW2) are prominent modes of energetic and dynamical coupling…”
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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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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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An update to the Horizontal Wind Model (HWM): The quiet time thermosphere by Drob, Douglas P., Emmert, John T., Meriwether, John W., Makela, Jonathan J., Doornbos, Eelco, Conde, Mark, Hernandez, Gonzalo, Noto, John, Zawdie, Katherine A., McDonald, Sarah E., Huba, Joe D., Klenzing, Jeff H.

“…The Horizontal Wind Model (HWM) has been updated in the thermosphere with new observations and formulation changes. These new data are ground‐based 630 nm…”
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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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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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Evidence for stratospheric sudden warming effects on the upper thermosphere derived from satellite orbital decay data during 1967-2013 by Yamazaki, Yosuke, Kosch, Michael J., Emmert, John T.

“…We investigate possible impact of stratospheric sudden warmings (SSWs) on the thermosphere by using long‐term data of the global average thermospheric total…”
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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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Seasonal Dependence of Geomagnetic Active‐Time Northern High‐Latitude Upper Thermospheric Winds by Dhadly, Manbharat S., Emmert, John T., Drob, Douglas P., Conde, Mark G., Doornbos, Eelco, Shepherd, Gordon G., Makela, Jonathan J., Wu, Qian, Nieciejewski, Richard J., Ridley, Aaron J.

“…This study is focused on improving the poorly understood seasonal dependence of northern high‐latitude F region thermospheric winds under active geomagnetic…”
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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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HL‐TWiM Empirical Model of High‐Latitude Upper Thermospheric Winds by Dhadly, Manbharat S., Emmert, John T., Drob, Douglas P., Conde, Mark G., Aruliah, Anasuya, Doornbos, Eelco, Shepherd, Gordon G., Wu, Qian, Makela, Jonathan J., Niciejewski, Rick J., Lee, Changsup, Jee, Geonhwa, Ridley, Aaron J.

“…We present an empirical model of thermospheric winds (High‐latitude Thermospheric Wind Model [HL‐TWiM]) that specifies F region high‐latitude horizontal…”
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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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Introduction to special issue on "Long-term changes and trends in the stratosphere, mesosphere, thermosphere and ionosphere" by Cnossen, Ingrid, Laštovička, Jan, Emmert, John T.

“…This special issue bundles some of the latest results on decadal‐scale variations in the stratosphere, mesosphere, thermosphere, and ionosphere, following on…”
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