Research Highlights

Research Highlights

A selection of highlights culled from publications by HAO staff.

Heat flux/SAPS impacts on SAR arcs

SubAuroral Red Arcs Generated by Inner Magnetospheric Heat Flux and by SubAuroral Polarization Streams

Dong Lin, Wenbin Wang, Mei-Ching Fok, Kevin Pham, Jia Yue, and Haonan Wu, utilize first-principles inner magnetosphere model and ionosphere-thermosphere model to illustrate the thermodynamic coupling effects between the topside ionosphere and the magnetosphere, and compare the relative significance between the heat flux and plasma convection due to electrodynamic coupling. 

SDO and DKIS data

On the intermittency of hot plasma loops in the solar corona

P. Judge and N.P.M. Kuin ask why and how are entire hydromagnetic structures only intermittently loaded with bright coronal plasma in the Sun? Their findings consolidate the claim that unobserved physical processes are at work which govern the heating of long-lived coronal loops.

Graph of polarimetric errors

Erratum: Analysis of Seeing-Induced Polarization Cross-Talk and Modulation Scheme Performance

R. Casini, A. G. de Wijn, P. G. Judge analyze (Published 2012 September 4) the generation of polarization cross-talk in Stokes polarimeters by atmospheric seeing, and its effects on the noise statistics of spectropolarimetric measurements for both single-beam and dual-beam instruments.

Hanle diagrams

A unifying polarization formalism for electric- and magnetic-multipole interactions

R. Casini, R. Manso Sainz, A. Lopez Ariste, and N. Kaikati extend the spherical tensorial formalism for polarization to the treatment of eletric- and magnetic-multipole transitions of any order, to model the radiation anisotropy affecting the scattering of radiation in an electric-quadrupole transition, and the associated Hanle effect in the presence of a magnetic field.

Longitude-latitude distribution map

A Community Ionosphere-Thermosphere Observing System Simulation Experiment (OSSE) Tool

Chih-Ting Hsu, et al. in this study demonstrate the utility of DART/TIEGCM as an IT OSSE tool, using synthetic observations simulated using a currently planned NASA Geospace Dynamics Constellation (GDC) observing system design. Five sets of OSSEs are carried out to compare the effects of assimilating various combinations of prospective GDC observations (e.g., neutral temperature, neutral wind, neutral composition, atomic oxygen ion density, and ion and electron temperature) during a major geomagnetic storm period of the St Patrick's Day Storm on March 17, 2013. 

pre-reversal enhancement during geomagnetic quiet time period

MAGE Model Simulation of the Pre-reversal Enhancement and Comparison with ICON and Jicamarca ISR Observations

Qian Wu, Wenbin Wang, Dong Lin, Liying Qian, Chaosong Huang, and Yongliang Zhang use the latest coupled geospace model MAGE (Multiscale Atmosphere-Geospace Environment) and observations from Jicamarca ISR and ICON IVM instrument, we examine the pre-reversal enhancement during geomagnetic quiet time period.

Thermospheric wind observations from HIWIND

HIWIND Balloon and Antarctica Jang Bogo FPI High Latitude Conjugate Thermospheric Wind Observations and Simulations

Qian Wu, Dong Lin, Wenbing Wang, Liying Qian, Geonhwa Jee, Changsup Lee, and Jeong-han Kim use balloon instrument in the northern hemisphere and ground based instrument in the southern hemisphere to study the conjugacy of the thermospheric winds of high latitudes.

Intraseasonal variability regression patterns

Tropical and Subtropical South American Intraseasonal Variability: A Normal-Mode Approach

André SW Teruya, Víctor C Mayta, Breno Raphaldini, Pedro L Silva Dias, and Camila R Sapucci use a normal-mode decomposition method to analyze South American intraseasonal variability (ISV). This demonstrated that a realistic circulation can be reproduced, giving a powerful tool for diagnosing and studying the dynamics of waves and the interactions between them in terms of their ability to provide causal accounts of the features seen in observations.

Measurement of gravity wave activity

Assessment of gravity waves from tropopause to thermosphere and ionosphere in high-resolution WACCM-X simulations

H.-L. Liu, P. H. Lauritzen, F. Vitt, and S. Goldhaber have developed a high-resolution whole atmosphere model (WACCM-X), which extends from the Earth surface to the upper thermosphere, that can partially resolve the small scale wave quantification.