Theory and observations of upward field-aligned currents at the magnetopause boundary layer.
Geophys Res Lett
; 42(21): 9149-9155, 2015 Nov 16.
Article
en En
| MEDLINE
| ID: mdl-29056784
ABSTRACT
The dependence of the upward field-aligned current density (Jâ) at the dayside magnetopause boundary layer is well described by a simple analytic model based on a velocity shear generator. A previous observational survey confirmed that the scaling properties predicted by the analytical model are applicable between 11 and 17 MLT. We utilize the analytic model to predict field-aligned currents using solar wind and ionospheric parameters and compare with direct observations. The calculated and observed parallel currents are in excellent agreement, suggesting that the model may be useful to infer boundary layer structures. However, near noon, where velocity shear is small, the kinetic pressure gradients and thermal currents, which are not included in the model, could make a small but significant contribution to Jâ. Excluding data from noon, our least squares fit returns log(Jâ,max_cal) = (0.96 ± 0.04) log(Jâ_obs) + (0.03 ± 0.01) where Jâ,max_cal = calculated Jâ,max and Jâ_obs = observed Jâ.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Geophys Res Lett
Año:
2015
Tipo del documento:
Article
País de afiliación:
Estados Unidos