Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.621 IF 1.621
  • IF 5-year value: 1.614 IF 5-year 1.614
  • CiteScore value: 1.61 CiteScore 1.61
  • SNIP value: 0.900 SNIP 0.900
  • SJR value: 0.910 SJR 0.910
  • IPP value: 1.58 IPP 1.58
  • h5-index value: 24 h5-index 24
  • Scimago H index value: 80 Scimago H index 80
Volume 30, issue 12
Ann. Geophys., 30, 1703-1707, 2012
https://doi.org/10.5194/angeo-30-1703-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
Ann. Geophys., 30, 1703-1707, 2012
https://doi.org/10.5194/angeo-30-1703-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.

ANGEO Communicates 17 Dec 2012

ANGEO Communicates | 17 Dec 2012

THEMIS observations of plasma transport via eddy diffusion

T. Izutsu1 and M. Fujimoto2 T. Izutsu and M. Fujimoto
  • 1Department of Earth and Planetary Science, The University of Tokyo, Tokyo, Japan
  • 2Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan

Abstract. We provide an event study of THEMIS observations of the low-latitude boundary layer in the dayside magnetosphere. Simultaneous multipoint observations obtained on 5 December 2008 show that the magnetosheath-like plasma in the low-latitude boundary layer is transferred earthward from the magnetopause. This earthward transport is accompanied by decrease in the density and fluctuating bulk flow. We calculate the eddy diffusion coefficients, which can be estimated from the observed velocity data, and found that the numbers are in good quantitative agreement with the spatial and time scales of the observed earthward transport signatures. It is shown that other possible plasma transport processes such as convection or diffusion induced by plasma wave turbulence are inconsistent with the observations. Our study strongly suggests that the observed transport is due to diffusive transport via turbulent eddy motions as is the case of an ordinary (Navier–Stokes) fluid.

Publications Copernicus
Download
Citation
Share