Related papers: Variations in magnetotelluric response functions c…
Observing the magnetic fields of low-mass interacting galaxies tells us how they have evolved over cosmic time and their importance in galaxy evolution. We have measured the Faraday rotation of 80 extra-galactic radio sources behind the…
The relationship between the behavior of an ancient geomagnetic field characteristics (paleointensity and frequency of inversions) and cyclic recurrence of endogenic and cosmogeneous processes which are conceivably connected with radial…
We report a calculation of time-dependent quasi-geostrophic core flows for 1940-2010. Inverting recursively for an ensemble of solutions, we evaluate the main source of uncertainties, namely the model errors arising from interactions…
This paper presents the equatorial ionospheric response to eleven strong-to-severe geomagnetic storms that occurred during the period 2000-2005, the declining phase of the solar cycle 23. The analysis has been performed using the global ion…
Spectropolarimetric observations used to infer the solar magnetic fields are obtained with a limited spatial resolution. The effects of this limited resolution on the inference of the open flux over the observed region have not been…
The total solar irradiance (TSI) varies on timescales of minute to centuries. On short timescales it varies due to the superposition of intensity fluctuations produced by turbulent convection and acoustic oscillations. On longer scale…
Solar magnetic activity follows regular cycles of about 11 years with an inversion of polarity in the poles every 22 years. This changing surface magnetism impacts the properties of the acoustic modes. The acoustic mode frequency shifts are…
The corrections to g-mode frequencies caused by the presence of a central magnetic field and rotation of the Sun are calculated. The calculations are carried out in the simple one dimensional magnetohydrodynamical model using the…
Due to the accuracy now reached by space geodetic techniques, and also considering some modelisations, the temporal variations of some Earth Gravity Field coefficients can be determined. They are due to Earth oceanic and solid tides, as…
We report a unique conjugate observation of fast flows and associated current sheet disturbances in the near-Earth magnetotail by MMS (Magnetospheric Multiscale) and Cluster preceding a positive bay onset of a small substorm at ~14:10 UT,…
In addition to the `facular' brightening of active regions, the quiet Sun also contains a small scale magnetic field with associated brightenings in continuum radiation. We measure this contribution of quiet regions to the Sun's brightness…
Fast changes of Earth's magnetic field could be explained by inviscid and diffusion-less quasi-geostrophic (QG) Magneto-Coriolis modes. We present a hybrid QG model with columnar flows and three-dimensional magnetic fields and find modes…
It is now well established that the quiet Sun contains in total more magnetic flux than active regions and represents an important reservoir of magnetic energy. But the nature and evolution of these fields remain largely unknown. We…
During strong magnetic storms, the errors of determination of the range, frequency Doppler shift and angles of arrival of transionospheric radio signals exceeds the one for magnetically quiet days by one order of magnitude as a minimum.…
This paper presents a comparative analysis of structural seismic responses under two types of ground motion inputs: (i) synthetic motions generated by stochastic spectral-compatible ground motion models and (ii) recorded motions from an…
It is shown that the Magnetotelluric (MT) impedance tensor admits an anti-symmetric generalized eigenvalue - eigenstate decomposition consistent with the anti-symmetry of electric and magnetic fields referred to the same coordinate frame:…
The aim of this paper is to extend our previous study of the solar-cycle variations of the meridional flows and to investigate their latitudinal and longitudinal structure in the subphotospheric layer, especially their variations in…
We present a new model of time-dependent flow at low latitudes in the Earth's core between 2000 and 2018, derived from magnetic field measurements made on board the {\it Swarm} and CHAMP satellites and at ground magnetic observatories. The…
Unsteady land-sea breezes (LSBs) resulting from time-varying surface thermal contrasts are explored in the presence of a constant synoptic pressure forcing, Mg, when the latter is oriented from sea to land versus land to sea. Large eddy…
Magnetic quenching of turbulent thermal diffusivity leads to instability of the large-scale field with the production of spatially isolated regions of enhanced field. This conclusion follows from a linear stability analysis in the framework…