Today, 06:22
(2025-04-23, 09:12)fiasco Wrote: I’m new to Blitzortung and just started diving into the lightning maps—super fascinating stuff! I'm located in central Italy and noticed that sometimes the strikes shown on the map are very close to where I am, almost too precise. I’m wondering, how accurate is the positioning of individual lightning strikes, especially in regions with fewer stations?
Also, does the number of active detectors in an area significantly affect the data I see? For example, if only a few stations are reporting, should I take the locations with a grain of salt?
Looking forward to learning more from all of you! Thanks in advance.
How Accurate? Remember, we're trying to locate the point where the impulse hits the ground.
From "Very Good"... I've chased down a handful of nearby strokes, which my Mark I Eyeball Sensor recorded as actual, within a handful of meters from what Blitzortung calculated and displayed. One of those was dead on the tree that blew apart. That was in the early days when we had very good satellite maps and could pretty much walk down a stroke nearby. Sigh... money and politics worldwide sorta killed that part of the fun years ago... sigh. We are, after all, volunteer, hobbyist, etc,
To "Best Guess" (heh)... if the ONLY detectors reporting an impulse were sending 'sombrero' (sky wave reflections, mostly lower Freqs) for example, with no sharp discharge data, the deviation can be quite large... kilometers,
OR "Expect 1 to 2 km" perhaps, average, worldwide???? A lightning impulse discharge can be 20-50km in length. It can produce multiple discharges. It can be positive or negative. energy can bounce off buildings, mountains, sky.... other noise can mess with the receivers analog signal shape, time... Energy/Time Data MIGHT be jumbled enough from best stations to 'assume' or 'calculate' a 'discharge point' anywhere along that original ionization path, producing an ugly deviation error. And if the best data sets for that impulse don't actually have clear 'discharge' peaks, using 'calculated' discharge times based on other data, than the calculated error can be so large the signal will be dropped!
Italy is right around the Home where Blitzortung was born, and Europe may have the highest 'density' of active receivers of any of our (currently) 13 or so region configurations... so odds of 8-17 of those receivers 'imaging' a well defined "discharge" signal (ground point) is much higher, and therefore the deviation will be minimal.
If you see strokes located, where 12-34+ stations are 'detecting' those strokes, and are within a range of 30- 150km, then you might assume that a single 'best channel' from ONLY up to 17 will be used to calculate the location, and this will likely produce the most accurate fix. BUT, while that is a neat rule of thumb, lightning is simply a weird beast, conditions change with every clock tick, and you'll have stations 600km, 1000km, even VERY distant, with data BETTER than those nearby!
Indeed, the system is refined enough that regions with poor station density are eagerly supported by other stations far away... who are fortunate enough to have a clean VHF environment, and well configured, optimized station operation. While they aren't necessarily pegging a discharge within meters, tens-of-meters up to maybe a km, is pretty darn good at times. Most likely a couple km. Still pretty cool for a bunch of 'hobbyists'.
"... should I take the locations with a grain of salt?" ... depends if you have a variable size piece you're calling a grain, and if you like more in your pasta, I suppose. In effect, a matter of taste?
For MY location, since I have no 'neighbor' stations within Ground Wave component distance, for deviation seasoning, I periodically sneak into the pasture over the hill, there, and steal the remains of a well-licked 50 pound (23 kilo) livestock salt block... or two.
