A5085673658- Ionosphere and magnetosphere dynamics
- Earthquake Detection and Analysis
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- GNSS positioning and interference
- Geophysics and Gravity Measurements
- Meteorological Phenomena and Simulations
- Astro and Planetary Science
- Planetary Science and Exploration
- Atmospheric Ozone and Climate
- Spacecraft Design and Technology
- Lightning and Electromagnetic Phenomena
- Oceanographic and Atmospheric Processes
- Reservoir Engineering and Simulation Methods
- Space exploration and regulation
- Ocean Waves and Remote Sensing
- Satellite Communication Systems
- Arctic and Antarctic ice dynamics
- Tropical and Extratropical Cyclones Research
- Underwater Vehicles and Communication Systems
- earthquake and tectonic studies
- Cardiovascular and Diving-Related Complications
- Mass Spectrometry Techniques and Applications
- Atmospheric aerosols and clouds
- Marine and environmental studies
Utah State University
2009-2020
The Earth’s Ionosphere-Thermosphere-Electrodynamics (I-T-E) system varies markedly on a range of spatial and temporal scales these variations have adverse effects human operations systems, including high-frequency communications, over-the-horizon radars, survey navigation systems that use Global Positioning System (GPS) satellites. Consequently, there is need to elucidate the underlying physical processes lead space weather disturbances both mitigate forecast near-Earth weather.
Abstract To address challenges of assessing space weather modeling capabilities, the Community Coordinated Modeling Center is leading a newly established International Forum for Space Weather Capabilities Assessment . This paper presents preliminary results validation modeled foF2 ( F 2 layer critical frequency) and TEC (total electron content) during first selected 2013 March storm event (17 2013). In this study, we used eight ionospheric models ranging from empirical to physics‐based,...
Abstract The goal of the Multimodel Ensemble Prediction System (MEPS) program is to improve space weather specification and forecasting with ensemble modeling. Space can have detrimental effects on a variety civilian military systems operations, many applications pertain ionosphere upper atmosphere. affect over‐the‐horizon radars, HF communications, surveying navigation systems, surveillance, spacecraft charging, power grids, pipelines, Federal Aviation Administration (FAA's) Wide Area...
High‐precision (∼0.5 K) measurements of OH Meinel (M) (6,2) rotational temperatures above the Bear Lake Observatory, UT (42°N, 112°W) during October 1996 have revealed an interesting and unexpected mean nocturnal pattern. Ten quality nights (>100 h) data been used to form a night for autumnal, near‐equinoctial conditions. The temperature RMS variability associated with this were 203 ± 5 K 2.4 K, respectively, compare very favorably expectations based on Na‐lidar tidal perturbations over...
Abstract The Earth's ionosphere is a highly dynamic region that almost constantly in state of flux. Solar radiation, geomagnetic activity, chemical reactions, and natural dynamics all act to perturb the ionosphere. changes on time scales hours days, with fine‐scale ionospheric structures are frequently observed lacking global physics‐based models due step spatial resolution constraints. To properly specify ionosphere, data needed, thus assimilation. Utah State University Global Assimilation...
The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety climatological model and the Automated Measurements Aerospace (ARMAS) statistical database are presented as polynomial fit equations. Using equations based on altitude, L shell, geomagnetic conditions an effective dose rate any location from a galactic cosmic ray (GCR) environment can be calculated. A subset ARMAS is represented by second equation GCR plus probable relativistic energetic particle (REP; Van Allen belt REP)...
Two high‐precision CEDAR instruments, an OH Mesospheric Temperature Mapper (MTM) and a Na Lidar, have been used to investigate seasonal variability in the mid‐latitude temperature at ∼87 km altitude over western USA. Here we report observation of large perturbation mesospheric that occurs shortly after autumnal equinox close association with penetration planetary‐wave energy from troposphere into mesosphere. This has observed on three occasions exhibits departure up ∼25–30 K nominal trend...
Traveling atmospheric disturbances (TADs) are effective in transporting momentum and energy deposited at high latitudes to the midlatitude low‐latitude regions of thermosphere. They also act transport from lower thermosphere into upper Previously, model studies have been conducted determine characteristics isolated, single‐pulse TADs, but generation multiple TADs excited during pulsating storms not considered before. Here a high‐resolution global thermosphere‐ionosphere was used study basic...
Abstract In order to assess current modeling capability of reproducing storm impacts on total electron content (TEC), we considered quantities such as TEC, TEC changes compared quiet time values, and the maximum value during a storm. We obtained from ionospheric models against ground‐based GPS measurements 2006 AGU event (14–15 December 2006) in selected eight longitude sectors. used 15 simulations models, including empirical, physics‐based, coupled ionosphere‐thermosphere, data assimilation...
Data assimilation models like the Utah State University (USU) Global Assimilation of Ionospheric Measurements (GAIM) use physics‐based ionosphere, ionosphere‐plasmasphere, or thermosphere and a Kalman filter as basis for assimilating diverse set measurements. With sufficient amount data with multiple types, can provide reliable specifications near‐term forecasts. However, long‐term forecasts (5 days longer) stand‐alone coupled are needed. Unfortunately, various contain several uncertain...
Abstract The Utah State University Global Assimilation of Ionospheric Measurements‐Gauss Markov model has been used to investigate the distribution ionospheric plasma during storm times over continental United States. Storm periods dramatically increase effects space weather on ionosphere and upper atmosphere, leading impacts over‐the‐horizon radars, Positioning System location determination, spacecraft charging, power grid overloads, disruption Federal Aviation Administration Wide Area...
[1] Waves in the atmosphere, ionosphere, magnetosphere, and oceans are important mechanisms for dissipating distributing energy throughout Earth-atmosphere system. Internal waves extremely past global studies have looked at impacts of gravity on thermosphere using wave parameterizations. Here, contrast, a medium-scale is studied thermosphere-ionosphere model, to determine 3-D characteristics as it propagated upward through thermosphere. The model used time-dependent, high-resolution,...
The classical polar wind is an ambipolar outflow of ions from high latitudes along open geomagnetic field lines. consists light thermal (H + , He ) and energetic heavy O ). characteristics these have been studied quite extensively since the 1960s. In just last 20 years, however, neutral atoms (ENAs) that are produced in charge exchange reactions between singly ionized surrounding used as a means to remotely probe plasma populations. Recent estimates for integrated fluxes LENA instrument on...
During high‐speed stream (HSS) events the solar wind speed increases, and cross polar cap potential leading to increased Joule heating at high latitudes. The heat input latitudes heats regions, which then conducts lower latitudes, producing global heating. occurs during risetime of throughout period as seen in our simulation. These simulations are performed using Utah State University thermosphere model driven by rates that consistent with electric fields observed DMSP‐15 observations HSS...
Abstract Physics‐based Data Assimilation (DA) has been shown to be a powerful technique for specifying and predicting space weather. However, it is also known that different data assimilation models simulating the same geophysical event can display weather features even if are assimilated. In this study, we used our Multimodel Ensemble Prediction System (MEPS) of DA elucidate similarities differences in individual model reconstructions mid‐low latitude ionosphere when averages were obtained....
The neutral polar wind shows a highly dynamic structure that depends on the characteristics of convection and precipitation. ions in are dependent electric fields at high latitudes, their outflow dynamics modified by heat input precipitating electrons auroral zone. A new three‐dimensional model has been developed which takes into account convecting ion heating due to zone, along with charge exchange between background thermal geocoronal atoms. results show over caps particles exhibit...
Physics-based data assimilation models have been used in meteorology and oceanography for several decades are now becoming prevalent specifications forecasts of the ionosphere. This increased use ionospheric coincides with increase suitable assimilation. At USU we developed different models, including Global Assimilation on Ionospheric Measurements Gauss-Markov (GAIM-GM) Full Physics (GAIM-FP) models. Both assimilate a variety types, ground-based GPS/TEC, occultation, bottomside electron...
Abstract A new field‐aligned current system in the high‐latitude ionosphere has been discovered. The finding was based on reconstructions from Ionospheric Dynamics and Electrodynamics Data Assimilation Model with ingestion of ground‐based magnetometer measurements. develops evolves along ionospheric terminator, it is thus termed as terminator currents. This first that not directly driven by magnetospheric dynamics an origin. study will help us to explore active role magnetosphere‐ionosphere...