Having fun with seemingly small (20 min) big date intervals between the vibrant tension procedures, we implicitly believe that the changes regarding the magnetopause updates generally come from the changes regarding the solar cinch pressure and differences of the dayside field-lined up Part 1 currents. While the magnetotail latest may have a slightly big response day, however in standard they merely intensifies the outcome of your own Part 1 current. g., particular estimations have been made within the Samso ); not, (1) the brand new noncoupled MHD model which overall performance have been presented over do perhaps not replicate the latest band latest and you will (2) the period of band latest intensification might be a great deal more than the step three–4 time used in these types of simulations. I show results of one’s coupled models lower than that is qualitatively much like the outcome of the noncoupled design, and this will not transform our findings.

Fundamentally, we would like to examine several operates to confirm which our email address details are design-independent. Desk 1 accumulates the advantage rules indices N when you look at the (1) determined away from six types off about three global MHD designs. The foremost is the fresh noncoupled SWMF model whoever efficiency were exhibited more than. Along with the first runs (Variation step 1), i simulated around three other brands of a comparable noncoupled model, a couple that have a higher ionospheric conductivity and something having a great dipole tip. The latest top-integrated Pedersen conductivity is assumed becoming equivalent to 5 S in every the fresh new sizes, except systems dos and you can step three in which the fresh new incorporated conductivity are 10 and you can one hundred S respectively. In variation cuatro, i simulated the fresh magnetosphere that have an effective dipole tilt 29° . Changes in Letter between Systems step 1 and you will dos and you may Sizes 1 and you may 4 is small, and you may between Models 1 and you can 3 was moderate, but simply for brand new southward IMF. Observe that the fresh ionospheric conductivity a hundred S may be very high and you will should be rarely observed in truth. I show it simply to illustrate the newest role away from conductivity since the both moments rise in conductivity for the Type dos alter N only for the fresh speed raise which have southward IMF.

An increase in brand new magnetotail current too boost in the fresh new Part step one currents weakens new magnetospheric magnetized industry and you may motions this new dayside magnetopause earthward

Type 5 means runs of the SWMF design along with complete internal-magnetosphere ionosphere, and Version six ‘s the LFM-Mix design. Each version, we build five runs towards the northward/southward IMF and for the thickness and velocity increases once the informed me above (twenty four works overall). Bear in mind one Letter=six from the top theoretic case if the magnetopause updates fits the stress harmony between your solar power snap active stress as well as the Planet’s dipole career and you can Letter=six.6 regarding the empirical Shue ainsi que al. ( 1998 ) model. Indeed, all of the gotten Letter is actually anywhere between those two beliefs or a bit less. Four from half dozen systems assume N huge otherwise equal to eight regarding the operates to your density boost for southward IMF. Although Version 5 forecasts Letter smaller compared to eight, Letter try methodically large in cases like this per model.

At the same time, Tsyganenko and you may Sibeck ( 1994 ) listed the get across-tail most recent along with a smaller studies the fresh ring current along with the region step 1 currents influence brand new magnetic profession on magnetospheric side of the magnetopause

In addition to the comparison of different models, we investigate the influence of grid resolution on our results. We have calculated two runs for the same southward IMF with gaydar density and velocity changes using the noncoupled SWMF model with the 1/16 R_E grid spacing around the subsolar magnetopause. We obtain different power laws, N=6.712 and 6.132, in the density and velocity runs, respectively (instead of 7.80 and 6.69 for the same model with a low resolution). Moreover, the normalized (to the solar wind electric field) reconnection rates in the low-resolution runs are smaller than those in the high-resolution runs (but are about the same in the density and velocity runs for the same resolution). We also find some differences in the CPCP and the magnetic field magnitude at geosynchronous orbit. We note that the grid resolution influences the magnitude of maximal electric current density at the magnetopause and possibly may change the total magnetopause current, but this problem requires more careful studies and it stays outside of the scope of the paper.