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Assessment of neutral atmospheric delay predictions based on the temporal resolution of an atmospheric model
(2020-01-01)
In Global Navigation Satellite Systems (GNSS), the effects of neutral atmosphere in electromagnetic signal propagation impacts directly on the quality of the final estimated position, leading to errors in the metric order. ...
Assessing ZWD models in delay and height domains using data from stations in different climate regions
(2022-03-01)
Global Navigation Satellite System (GNSS) has revolutionized activities involving geodetic positioning. To achieve a desired accuracy, it is essential to model the atmosphere in an appropriate way. With respect to the ...
50 years of synergy between space geodesy and meteorology: From a GNSS positioning error to precipitation nowcasting applications50 anos de sinergia entre geodésia espacial e meteorologia: Do erro no posicionamento GNSS a aplicações de previsão de precipitação de curtíssimo prazo
(2020-12-01)
The neutral atmosphere (or troposphere) causes refraction in radio frequency signals, which results in errors in Global Navigation Satellite Systems (GNSS) measurements. In meteorology, this effect can represent important ...
Improving the Ni I atomic model for solar and stellar atmospheric models
(IOP Publishing, 2013-05-10)
Neutral nickel (Ni I) is abundant in the solar atmosphere and is one of the important elements that contribute to the emission and absorption of radiation in the spectral range between 1900 and 3900 Å. Previously, the Solar ...
Whole atmosphere modeling: Connecting terrestrial and space weather
(American Geophysical Union, 2011-11-12)
At the turn of the century R. G. Roble advanced an ambitious program of developing an atmospheric general circulation model (GCM) extending from the surface to the exosphere. He outlined several areas of research and ...
Effects of atmospheric stability conditions on the pollutants dispersion near roads using CFD
This study quantifies the effects of atmospheric stability conditions on the concentration of atmospheric pollutants near roads. We used as a base case scenario the resulting concentrations obtained solving numerically the ...
Modeling the low-latitude thermosphere and ionosphere
(Elsevier, 2002-08)
The National Center for Atmospheric Research thermosphere/ionosphere/electrodynamic general circulation model (TIEGCM) is one of the few models that self-consistently solves the coupled equations for the neutral atmosphere ...
Three-Dimensional Wind Measurements and Modeling Using a Bi-Static Fabry-Perot Interferometer System in Brazil
(University of Illinois at Urbana-Champaign, 2013)
The earth’s upper atmosphere has been studied for over a century now, and while a multitude of data has been collected studying the plasma in the ionosphere, there are not equivalent amounts of data on neutrals in the ...
Multimodel comparison of the ionosphere variability during the 2009 sudden stratosphere warming
(American Geophysical Union, 2016-07-18)
A comparison of different model simulations of the ionosphere variability during the 2009 sudden stratosphere warming (SSW) is presented. The focus is on the equatorial and low‐latitude ionosphere simulated by the ...
SAMI3/SD‐WACCM‐X simulations of ionospheric variability during northern winter 2009
(American Geophysical Union, 2015-08-07)
We have performed simulations using the Naval Research Laboratory's physics‐based model of the ionosphere, Sami3 is A Model of the Ionosphere (SAMI3), to illustrate how neutral wind dynamics is responsible for day‐to‐day ...