An Assessment of the Interaction Between Solar Impacts and Pre-Existing Cyclonic Storm Structures.
Whilst there is significant circumstantial evidence to support the theory that a correlation exists between the impact of a large incoming solar event and an increase in the intensity of pre-existing major surface storm centres, the question remains, of course, what are the precise mechanisms whereby such an event could trigger a large scale increase in the intensity of surface meteorological activity.
We know already that pressure and thermal atmospheric profiles are significantly influenced and affected by these impacts, that these profile changes undoubtedly have an impact on the behaviour and movement of surface storms and that the steepening of the pressure profile particularly, significantly increases the intensity of surface activity.
However, it is also possible that a tertiary influence may come in to play if that storm is sufficiently large and sufficiently well focussed – as in the case of a large tropical storm.
If we examine the nature of what a large storm actually is – basically an energy driven, large, rotating mass consisting primarily of water – we may then examine the dynamics of what such a large physical object may be subjected to and determine how that object may then react.
As the structure is mostly water, in various forms, it is self evidently an electrically conductive mass. As that mass is rotating at significant velocity it will, again self evidently, generate the electric and magnetic fields to be associated with such a mass. We may then assume that these fields will be interacting with the overall geomagnetic field. It would not, therefore, be unreasonable to assume that large scale fluctuations and localised increases in the intensity of the geomagnetic field resulting from a solar impact will affect the behaviour of the storm and potentially significantly accelerate the speed of rotation.
Whilst a great deal more research is needed into this phenomenon, recent events gave us the opportunity to test the theory by practical observation. Of particular relevance is storm ‘Harvey’, which caused such devastating effects in the southern USA coastal region. We may use this event to assess the relevance of the factors involved.
It was noted at the time that this particular storm, originally a relatively small tropical storm which had almost died out, suddenly accelerated from almost nothing to category 5 over just a few days, an almost unprecedented rate of growth and certainly not one that could be attributed to surface thermal factors such as air and water temperatures alone without some external stimulus.
Clearly, the energy contained in a solar impact event is substantially less than that involved in the structure of a major storm, however, having injected the relevant impetus into the system, normal thermal energy factors would become more aggressively involved, accelerating the mass of the storm at the increased rate observed.
The probability is that the combination of localised pressure surging, combined with electromagnetic effects result in the effects observed.
‘Harvey’ –Growth profile.
Assessing then the solar impact data we can judge the probability of any impact having had the noted effect.
The Kp index for the relevant period does indeed, show a major spike immediately preceding the sudden growth of ‘Harvey’.
We need then to examine the magnetic fluctuation graphs for the same period.
Magnetometer ‘Kevo’ August 2017
Magnetometer ‘Thule’ August 2017
Charts from both Kevo and Thule stations show a dramatic surge at the time.
Examining the data related to other storms during that particular season tends to confirm the conclusion as we correlate and cross reference the relevant information. It does seem that this season was somewhat unusual in that specific pre-existing surface events were present at the exact time that a series of solar impact events occurred. A case of ‘exactly the right conditions, exactly the right triggers, exactly the right time’. The sharp spike in activity is starkly apparent in the chart..
Looking back over previous seasons is somewhat hampered by the lack of availability of relevant data. To further the research it will be necessary to monitor future seasonal weather patterns in the light of solar behaviour and to more deeply assess the electrical and magnetic environment associated with large scale surface storm events.
If we try to look further back in time for possible similar events and influences, we are even more greatly constrained by the limited available data. However, historically notable events can give us some interesting coincidences. For example, a sudden major impact recorded as AP=110 occurred on 23rd/24th August 2005; this coincided exactly with the genesis of the infamous hurricane ‘Katrina’. Slightly later in the same season, repeated impacts occurred September 11th to 15th, coinciding with hurricane ‘Ophelia’ noted for it’s erratic, unpredictable behaviour, surging in both intensity and direction and defying all attempts at prediction. While we cannot definitely link these events they appear far too close to be entirely coincidental.