‘Being an Analysis of Atmospheric Influences
During Hurricane Season 2017′
Perhaps the most significant aspect of late summer – early autumn 2017 was the severity of the hurricane season, especially in the Caribbean / Atlantic region. We may therefore seek to make an analysis of the atmospheric activity and solar influences to assess whether there has been any relevant interaction or correlation in that area of interest.
It has been well recorded that, over the preceding months, most aspects of solar activity had been steadily declining, although Kp and Ap indices had been showing a somewhat contrary upswing. This influence, coincidentally, came to a peak just as the Hurricane season was starting and continued throughout the months of August, September and into October.
UPDATES 2018 SEASON…..
As a follow-on, it is notable that the 2018 season was strikingly different. Hurricane activity in the Caribbean and Atlantic basin was completely absent early in the season and reduced in the Pacific. According to N.O.A.A. -“This is the first August since 1997 to have had zero tropical storm formations in the Atlantic basin south of 30N”. Kp activity was also very flat at this point in time.
K-index Ap index TCI
This changed on 26th August 2018 with a very strong solar impact reaching Kp7. Within a week of this impact, a series of storms developed into hurricanes in the Atlantic (‘Gordon’ and ‘Florence’) and an increase in the intensity of activity in the Pacific (‘Norman’ and ‘Olivia’) was noted. (see : ‘OBSERVATIONS’). Florence went on to cause significant damage in the Carolinas, not so much because of the high wind speed (Cat.2 on impact) but because of the very slow speed of movement and resulting excessive rainfall and storm surge. The decline in Kp activity after this event was accompanied by a steady decline in storm strength in both main areas.
A sharp burst of ‘Kp’ activity recorded 7th/8th October 2018 was followed by an identifiable increase in Atlantic/Pacific Hurricane activity 9th/10th October. NHC reports – “…LESLIE BECOMES A HURRICANE AGAIN … MICHAEL BECOMES CATEGORY 4 …NADINE STRONGER …SERGIO ACCELERATING..” (10thOcober 2018)
‘HARVEY’ – Recorded peak intensity and (below) overall progress.
(——— Impact————-) (– Response–)
‘IRMA’– Recorded peak intensity and (below) overall progress.
‘JOSE’– Recorded peak intensity and (below) overall progress.
‘MARIA’– Recorded peak intensity and (below) overall progress.
‘OPHELIA’ – Recorded peak intensity and (below) overall progress.
On assessing the relevant charts and cross-correlating the data, there does appear to be significant coincidence in the timing between the arrival of a ‘Kp’ impact and a corresponding increase in the intensity of the storm activity. Even with ‘Ophelia’ which, by both position and time should have been declining and had shown signs of starting to decline in intensity, showed a sudden increase coincident with the impact 11th to 15th October. This storm went on to cause significant damage in Ireland and South West UK.
This chart (above, courtesy NOAA) shows the anomalous increase in Ap index over recent years, and displays well the sudden upswing during August and September 2017, coincident with the unusually intense Hurricane activity during that season
The deep atmosphere chart, above, shows that there was little steering activity present during the development of ‘Harvey’, allowing coastal interaction to become the dominant steering force. This tendency appears to have been a factor influencing the path of several of the storms this year.
Clearly there are many factors involved in the generation of a tropical storm, from atmospheric thermal and pressure profiles to the geo-magnetic environment. However, it is evident that incoming solar activity plays a significant role in the development and growth of this activity, potentially giving aggressive impetus to all of the factors involved. It is, as always, important to remember that short term ‘spikes’ may be lost in the monthly or long term averaging process however it should also be remembered that such short term activity may have significant impact on the Earthly surface atmosphere.
Kp Impact August/September 2019
Atlantic Chart 02-Sep-2019