Their accurate computation of frequency dispersion saves vertical resolution and hence is capable of predicting the onset of wave breaking.
On the other hand, discontinuous IMF changes appears to be related to the onset of wave and changes in waveform both in space and on the ground.
Here, we study not the first notable peak in wave amplitude, but the onset of wave activity as defined by the AWESOME algorithm (Murphy et al. 2009a), and we extend the analysis from Pi1 waves, through the long-period Pi1 band, to Pi2 waves to study all frequencies (see Murphy et al. 2011a).
We found in analyzing solar wind and IMF data that changes in IMF, especially discontinuities, appears to be related to the onset of wave and changes in wave form both in space and on the ground, as seen in the most of events examined in this study.
To quantify this responsiveness of the wasp to shimmering, the change in distance of the hornet within one second after the onset of waving (Δdxz(1s)) was chosen.
In detail, the investigation was on whether the strength of the shimmering waves (W) was dependent on the flight parameters of the hornet (dxz, vdxz, vf) in the pre-wave period, 400 ms before the onset of waving.
The time correlations of the original data over a number of discrete time intervals in 40 ms steps were proved (e.g. from time zero to 400 ms after the onset of waving) and was adjusted for ties.
The electrophysiological threshold was obtained by the stimulus presented at decreasing intensities, until the lowest intensity that triggered the onset of wave V for click (2000 a 4000 Hz) and 500 and 1000 Hz tone bursts.
We note here that there is no overlap in uncertainty between the onsets of the different ULF wave bands, demonstrating that the onset of Pi1-2 waves occurs prior to Pi2 waves, and both occur prior to the higher frequency Pi1 wave band consistent with previous studies at single stations (Murphy et al. 2009a, b; Rae et al. 2009a, b; Walsh et al. 2010).
The aim of the experiment – to observe the onset of hydrothermal waves and to measure their features, like the waves phase speed and the angle between the wave vector and the applied temperature gradient – was reached.
