National Aeronautics and Space Administration

Living With A Star

Targeted Research and Technology

Competing Pathways of Radiation Belt Response to Solar Interplanetary Structures

Project URL:

ROSES ID: NNH13ZDA001N      Selection Year: 2013      

Program Element: Targeted Science Team

  • Science Topic: Connection between Solar Interplanetary Structures and the response of Earth’s radiation belts

Principal Investigator: Alex Glocer

Affiliation(s): NASA Goddard Space Flight Center

Project Member(s):
Khazanov, George V. Co-I NASA/GSFC
Bortnik, Jacob Co-I University of California, Los Angeles
Sibeck, David G Collaborator NASA/GSFC
Kanekal, Shri G Collaborator NASA Goddard Space Flight Center
Huba, Joseph Co-I Naval Research Laboratory
Fok, Mei-Ching Hannah Co-I NASA Goddard Space Flight Center
Borovsky, Joseph Co-I Space Science Institute
Dorelli, John Charles Co-I NASA GSFC
Gopalswamy, Natchimuthuk Collaborator NASA Goddard Space Flight Center


Goals and Objectives: The response of the outer radiation belt to solar interplanetary structures is notoriously unpredictable. Such unpredictability is likely due to the numerous competing pathways through which Coronal Mass Ejections (CMEs), Corotating Interaction Regions (CIRs), and other structures can influence radiation belt sources and losses. It is the overarching goal of this proposal to understand what are the factors associated with interplanetary structures that affect the radiation belts, and to understand the pathways by which those factors exert their influences. Specifically, we will focus on the following objectives:

1) Identify the features of solar interplanetary structures associated with radiation belt sources and losses, and characterize how specific solar wind structures affect the radiation belt fluxes

2) Characterize and explain the pathways through which solar interplanetary structures regulate the wave environment, by:

a. Exploring the response of the plasmasphere, which is vitally important in understanding the propagation of waves, to these structures

b. Quantifying the response of the ring current electrons and ions, which provide the free energy for many of the important waves in the inner magnetosphere.

c. Characterizing how the magnetospheric composition changes in response to solar interplanetary structures. Knowledge of composition is vital to understanding wave generation and propogation.

d. Understanding the resulting generation and propagation of ULF, EMIC, Chorus and other waves in the magnetosphere

3) Identify how magnetospheric boundaries change in response to interplanetary structures and the consequences for sources and losses of radiation belt fluxes.

4) Translate the impact of solar interplanetary structures on the wave-environment and magnetospheric boundaries and plasma parameters to radiation belt fluxes.

5) Explain why and when pathways of influence dominate over competing ones.

Methodology: To achieve our objectives we propose a tightly integrated and well-coordinated Targeted Science Team (TST) to carry out a four-year study. Our TST will include observational studies correlating and characterizing the detailed space-time structures of interplanetary features impinging on the Earths magnetosphere with observations of the response of the radiation belts, global simulations (fully coupled magnetosphere, ring current, radiation belt, plasmasphere) of the magnetospheric response to these structures, and studies of wave generation and damping and the impact on radiation belt electrons. The core numerical models to be used include resistive, anisotropic and multi-fluid versions of the BATS-R-US magnetosphere code, the Comprehensive Ring Current Model (CRCM), the Radiation Belt Environment (RBE) model, and the SAMI3 model for the plasmaphere. Data for the observational aspects of the study will be drawn from various satellites including ACE, WIND, CLUSTER, THEMIS, SAMPEX, GOES, and the recently launched Van Allen Probes.

This work is directly related to LWS strategic goal number 3 which seeks to "...deliver the understanding and modeling required for effective forecasting/specification of magnetospheric radiation and plasma environments" to mitigate the effects of space weather on valuable space based assets.


Performance YearReferenceInvestigation TypeActions
3Kang S.-B.; Fok M.-C.; Glocer A.; Min K.-W.; Choi C.-R.; Cho...
Theory and Model Development
3Glocer A.; Dorelli J.; Toth G.; Komar C. M.; Cassak P. A.; (...
Theory and Model Development
2Dixon P.; MacDonald E. A.; Funsten H. O.; Glocer A.; Grande ...
Data Model Comparison
1Khazanov G. V.; Tripathi A. K.; Singhal R. P.; Himwich E. W....
1Fok M.-C.; Buzulukova N. Y.; Chen S.-H.; Glocer A.; Nagai T....
Theory and Model Development
1Khazanov G. V.; Glocer A.; Himwich E. W.; (2014). Magnetosph...
1Denton M. H.; Borovsky J. E.; (2014). Observations and model...
Data Model Comparison
2Bortnik J.; Li W.; Thorne R. M.; Angelopoulos V.; (2016). A ...
Theory and Model Development
2Li W.; Thorne R. M.; Bortnik J.; Baker D. N.; Reeves G. D.; ...
Data Analysis
2Ni B.; Cao X.; Zou Z.; Zhou C.; Gu X.; Bortnik J.; Zhang J.;...
Theory and Model Development
3Li J.; Ni B.; Ma Q.; Xie L.; Pu Z.; Fu S.; Thorne R. M.; Bor...
3Borovsky J. E.; Denton M. H.; (2016). Compressional perturba...
Data Model Comparison
2Xu F.; Borovsky J. E.; (2015). A new four-plasma categorizat...
Theory and Model Development
3Borovsky J. E.; Cayton T. E.; Denton M. H.; Belian R. D.; Ch...
Data Analysis
3Cassak P. A; Genestreti K. J.; Burch J. L; Phan T.-D.; Shay ...
Data Model Comparison
3Komar C. M.; Glocer A.; Hartinger M. D.; Murphy K. R.; Fok M...


Performance YearReferenceActions
1Komar, C. M.; Glocer, A.; Hartinger, M.; Fok, M. C....

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