What is the KP Aurora Index?
What is the KP Aurora Index?
The KP Index is a global geomagnetic activity scale that determines the earth’s magnetic field strength, based on 3 hour measurement intervals done from ground-based magnetometers centers. The index ranges from 0-9 where 0 means there’s very little geomagnetic activity taking place, whereas 9 translates to intense geomagnetic storming. Generally, the lesser the figure found on your Kp-index the fewer your chances of seeing an Aurora Borealis, and the more the number the more spectacular the northern lights would be.
Usually, each measurement station is calibrated based on its latitude and sends back a specific K-indice, depending on the geomagnetic action recorded at the particular magnetometer center. The magnetometer works by measuring the total deviation of the horizontal module of a magnetic field found in its location, then reports this information so that it can be used to determine the intensity of aurora borealis in a specific location.
How the scale works in predicting northern lights
Basically, the KP scale system shows where geomagnetic activity is most prevalent and thus the likelihood of seeing strong auroras. Through experience, researchers can tell where auroras are noticeable and at what level of the KP Index they were seen at. For instance, they can plot a map and estimate that a particular region experiences northern lights when KP6 level is reached. However, even if the map indicates that you need KP6 to view Aurora Borealis, you can still go out when it’s reading KP5 and get lucky since these figures are just estimates.
Based on research, it has been found that some of the strongest auroras on earth occur in Iceland and some parts of Northern Spain, where the KP Indexes are considerably high.
Additionally, auroras are closely associated with geomagnetic storms which are marked from G1 to G5. This phenomenal occurs when there’s very strong geomagnetic activity caused by buildup in the planet’s magneto-tail, thereby resulting in magnetic re-connection and snap-back which accelerates particles back towards the earth to spark some magnificent northern lights displays. The best thing is that geomagnetic storm levels (G) can be converted into KP which includes; G1=KP5, G2=KP6, G3=KP7, G4=KP8 and G5=KP9.
Typically, you will be able to see auroras in any high altitude location with a KP value of 4, but for areas that are in the middle latitude a KP value of 7 is required and much lower latitudes need a KP ratio of 8 to 9. While the KP figure you need to view northern lights depends on your specific location around the earth, in most cases the best auroras occur within the northern hemisphere.
To further increase your chances of watching an aurora, find a spot that provides you un-obscured views of the North where there’s no light pollution. Moreover, unless you’re near the northern pole, auroras won’t appear directly overhead but would likely be on the north horizon. Therefore, to maximize your prospects of seeing it, try finding a wide open field, hill or beach area that will give you un-obscured views of the sky. Even so, the most important point to remember in aurora-watching is the KP Scale.