Bibliography

Notice:

Clicking on the title will open a new window with all details of the bibliographic entry.
Clicking on the DOI link will open a new window with the original bibliographic entry from the publisher.
Clicking on a single author will show all publications by the selected author.
Clicking on a single keyword, will show all publications by the selected keyword.

Found 18 entries in the Bibliography.

Showing entries from 1 through 18

2017

Ionospheric-thermospheric UV tomography: 3. A multisensor technique for creating full-orbit reconstructions of atmospheric UV emission

We present the Volume Emission Rate Tomography (VERT) technique for inverting satellite-based, multisensor limb and nadir measurements of atmospheric ultraviolet emission to create whole-orbit reconstructions of atmospheric volume emission rate. The VERT approach is more general than previous ionospheric tomography methods because it can reconstruct the volume emission rate field irrespective of the particular excitation mechanisms (e.g., radiative recombination, photoelectron impact excitation, and energetic particle precipitation in auroras); physical models are then applied to interpret the airglow. The technique was developed and tested using data from the Special Sensor Ultraviolet Limb Imager and Special Sensor Ultraviolet Spectrographic Imager instruments aboard the Defense Meteorological Satellite Program F-18 spacecraft and planned for use with upcoming remote sensing missions. The technique incorporates several features to optimize the tomographic solutions, such as the use of a nonnegative algorithm (Richardson-Lucy, RL) that explicitly accounts for the Poisson statistics inherent in optical measurements, capability to include extinction effects due to resonant scattering and absorption of the photons from the lines of sight, a pseudodiffusion-based regularization scheme implemented between iterations of the RL code to produce smoother solutions, and the capability to estimate error bars on the solutions. Tests using simulated atmospheric emissions verify that the technique performs well in a variety of situations, including daytime, nighttime, and even in the challenging terminator regions. Lastly, we consider ionospheric nightglow and validate reconstructions of the nighttime electron density against Advanced Research Project Agency (ARPA) Long-range Tracking and Identification Radar (ALTAIR) incoherent scatter radar data.

Hei, Matthew; Budzien, Scott; Dymond, Kenneth; Nicholas, Andrew; Paxton, Larry; Schaefer, Robert; Groves, Keith;

Published by: Radio Science Published on: 07/2017

YEAR: 2017 DOI: 10.1002/2015RS005887

2015

SSULI/SSUSI UV tomographic images of large-scale plasma structuring

Hei, Matthew; Budzien, Scott; Dymond, Kenneth; Paxton, Larry; Schaefer, Robert; Groves, Keith;

Published by: Published on:

YEAR: 2015 DOI:

2014

Geomagnetic control of equatorial plasma bubble activity modeled by the TIEGCM with Kp

Describing the day-to-day variability of Equatorial Plasma Bubble (EPB) occurrence remains a significant challenge. In this study we use the Thermosphere-Ionosphere Electrodynamics General Circulation Model (TIEGCM), driven by solar (F_10.7) and geomagnetic (Kp) activity indices, to study daily variations of the linear Rayleigh-Taylor (R-T) instability growth rate in relation to the measured scintillation strength at five longitudinally distributed stations. For locations characterized by generally favorable conditions for EPB growth (i.e., within the scintillation season for that location), we find that the TIEGCM is capable of identifying days when EPB development, determined from the calculated R-T growth rate, is suppressed as a result of geomagnetic activity. Both observed and modeled upward plasma drifts indicate that the prereversal enhancement scales linearly with Kp from several hours prior, from which it is concluded that even small Kpchanges cause significant variations in daily EPB growth.

Carter, B.; Retterer, J.; Yizengaw, E.; Groves, K.; Caton, R.; McNamara, L.; Bridgwood, C.; Francis, M.; Terkildsen, M.; Norman, R.; Zhang, K.;

Published by: Geophysical Research Letters Published on: 08/2014

YEAR: 2014 DOI: 10.1002/2014GL060953

Equatorial ionosphere; plasma bubbles; TIEGCM

2013

Signatures of equatorial plasma bubbles in VHF satellite scintillations and equatorial ionograms

Since their discovery in the 1970s, equatorial plasma bubbles (EPBs) have been invoked to explain the propagation of VHF signals on trans-equatorial circuits at night, and blamed for highly detrimental scintillation of VHF and GHz trans-ionospheric communications signals in equatorial regions. Over the last four decades, the properties of EPBs have been deduced by multiple techniques such as incoherent scatter radar, 630 nm airglow, depletions in GPS total electron content observations, VHF and GHz scintillations, and HF observations by ionosondes. The initiation and evolution of EPBs have by now been successfully modeled and a good understanding developed of the underlying physics. However, different communities tend to concentrate on a single observing technique, without regard to whether the different techniques provide a consistent physical picture. In contrast, this paper discusses two very different types of observations made on a night-by-night basis during the COPEX campaign of late 2002 in Brazil, namely, VHF scintillations and ionograms, and shows that the two methods of observation can provide a consistent interpretation of the properties of EPBs. For example, an EPB seen as an eastward drifting scintillation event can also be seen as an extra ionogram reflection trace that moves closer to and then away from the ionosonde site. The scintillations are attributed to strong gradients across the walls of an EPB, whereas the extra ionogram traces are attributed to oblique reflection of the ionosonde signals from the walls of the EPB.

McNamara, L.; Caton, R.; Parris, R.; Pedersen, T.; Thompson, D.; Wiens, K.; Groves, K.;

Published by: Radio Science Published on: 03/2013

YEAR: 2013 DOI: 10.1002/rds.v48.210.1002/rds.20025

Equatorial ionosphere; equatorial plasma bubbles

2010

Coordinated study of coherent radar backscatter and optical airglow depletions in the central Pacific

Miller, E.; Makela, J.; Groves, K.; Kelley, M.; Tsunoda, R.;

Published by: Journal of Geophysical Research Published on: Jan-01-2010

YEAR: 2010 DOI: 10.1029/2009JA014946

A comprehensive rocket and radar study of midlatitude spread F

Earle, GD; Bhaneja, P; Roddy, PA; Swenson, CM; Barjatya, Aroh; Bishop, RL; Bullett, TW; Crowley, G; Redmon, R; Groves, K; , others;