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In the scalar part of this study, we determine various statistical relationships between estimated magnetic cloud (MC) model fit-parameters and sunspot number (SSN) for the interval defined by the Wind mission, i.e., early 1995 until the end of 2012, all in terms of yearly averages. The MC-fitting model used is that of Lepping, Jones, and Burlaga ( J. Geophys. Res. 95, 11957 - 11965, ). We also statistically compare the MC fit-parameters and other derived MC quantities [ e.g., axial magnetic flux (Φ) and total axial current density ( J)] with some associated ambient interplanetary quantities (including the interplanetary magnetic field ( B), proton number density ( N), and others). Some of the main findings are that the minimum SSN is nearly simultaneous with the minimum in the number of MCs per year ( N), which occurs in 2008. There are various fluctuations in N and the MC model-fit quality ( Q′) throughout the mission, but the last four years (2009 - 2012) are markedly different from the others; Q′ is low and N is large over these four years. N is especially large for 2012. The linear correlation coefficient (c.c.≈0.75) between the SSN and each of the three quantities J, MC diameter (2 R), and B, is moderately high, but none of the MC parameters track the SSN well in the sense defined in this article. However, there is good statistical tracking among the following: MC axial field, B, 2 R, average MC speed ( V), and yearly average solar wind speed ( V) with relatively high c.c.s among most of these. From the start of the mission until late 2005, J gradually increases, with a slight violation in 2003, but then a dramatic decrease (by more than a factor of five) occurs to an almost steady and low value of ≈ 3 μA km until the end of the interval of interest, i.e., lasting for at least seven years. This tends to split the overall 18-year interval into two phases with a separator at the end of 2005. There is good tracking between 2 R and the total axial current density, as expected. The MC duration is also correlated well with these two quantities. Φ shows marked variations throughout the mission, but has no obvious trend. N, B, V, Q′, and V are all quite steady over the full 18 years and have markedly low relative variation. Concerning vector quantities, we examine the distribution of MC type for the 18 years, where type refers to the field directional change through a given MC starting at first encounter ( i.e., North-to-South, or South-to-North, All South, All North, etc.). Combining all 18 years of MC types shows that the occurrence rate varies strongly across the various MC types, with N-to-S being most prevalent, with a 27 % occurrence rate (of all MCs), and S-to-N being second, with a 23 % occurrence. Then All N and All S come next at 16 % and 10 % occurrence rate, respectively. All others are at 7 % or lower. For the variation of MC types with time, the southern types ( i.e., those that start with a southern magnetic field, a negative B in geocentric-solar-ecliptic coordinates) decrease, as the northern types ( i.e., those that start with a northern field) increase, apparently consistent with the specific timing of the polarity change of the solar magnetic field, as predicted by Bothmer and Rust (in Crooker, N., Joselyn, J., Feynman J. (eds), Geophys. Monogr., 139 - 146, ). [ABSTRACT FROM AUTHOR]

The energetic charged particle, interplanetary magnetic field, and plasma characteristics of the `Bastille Day' shock and ejecta/magnetic cloud events at 1 AU occurring over the days 14–16 July 2000 are described. Profiles of MeV (WIND/LEMT) energetic ions help to organize the overall sequence of events from the solar source to 1 AU. Stressed are analyses of an outstanding magnetic cloud (MC2) starting late on 15 July and its upstream shock about 4 hours earlier in WIND magnetic field and plasma data. Also analyzed is a less certain, but likely, magnetic cloud (MC1) occurring early on 15 July; this was separated from MC2 by its upstream shock and many heliospheric current sheet (HCS) crossings. Other HCS crossings occurred throughout the 3-day period. Overall this dramatic series of interplanetary events caused a large multi-phase magnetic storm with min Dst lower than −300 nT. The very fast solar wind speed (≥ 1100 km s−1) in and around the front of MC2 (for near average densities) was responsible for a very high solar wind ram pressure driving in the front of the magnetosphere to geocentric distances estimated to be as low as ≈ 5 RE, much lower than the geosynchronous orbit radius. This was consistent with magnetic field observations from two GOES satellites which indicated they were in the magnetosheath for extended times. A static force-free field model is used to fit the two magnetic cloud profiles providing estimates of the clouds' physical and geometrical properties. MC2 was much larger than MC1, but their axes were nearly antiparallel, and their magnetic fields had the same left-handed helicity. MC2's axis and its upstream shock normal were very close to being perpendicular to each other, as might be expected if the cloud were driving the shock at the time of observation. The estimated axial magnetic flux carried by MC2 was 52×1020 Mx, which is about 5 times the typical magnetic flux estimated for other magnetic clouds in the WIND data over its first 4 years and is 17 times the flux of MC1. This large flux is due to both the strong axially-directed field of MC2 (46.8 nT on the axis) and the large radius ( R0=0.189 AU) of the flux tube. MC2's average speed is consistent with the expected transit time from a halo-CME to which it is apparently related. [ABSTRACT FROM AUTHOR]