(2024-06-06, 11:51)prune Wrote: Oh my goodness - how embarrassing! Thanks for deleting, and for adding your screenshot.
I’ve lived in Sydney a few months now and noticed this every time. There are definitely C-G strikes that are not showing.
When googling, I came across this old thread where receiver locations were showing in the wrong place on the map. Is there any chance that a similar error has snuck back in?
https://forum.blitzortung.org/printthread.php?tid=901
Anyone else in Sydney noticing the same thing so that I can stop worrying that I’m losing my marbles?
Oh no, you're not losing your marbles at all! The maps only display strokes that the computations could LOCATE a 'ground' point. C-G strokes. There are MANY reasons strikes may not be located. It doesn't mean they were not 'detected'. I'm not sure about the Oceania region, but typically good data for locating must be received from 8-17 stations... typically 12.
Blitzortung receivers are not designed for 'local' detection, unless configured for very low sensitivity.
Because of the extreme EM fields in storm cells, our sensitive receivers within, for example, 50 KM of an impulse, depending on configurations, receive so much overlapping data that the signals are worthless... it may be so 'rich' that the receivers will stop sending data, as designed. The network then uses the more distant stations >80km or so, as designed.
Again, data from e.g. 12 distant stations must pass criteria for an impulse to be 'located'.
So, if all the stations around Sydney had gone interference shutdown, and the data from distant receivers did not align, the stroke could NOT be 'located' and displayed on the map.
That's the quickest scenario to explain. There are MANY other reasons why strokes may not display.,.. for example a stroke could be airborne for 40km before grounding, with so many cascades prior to grounding, that timing simply can't be established. Others the stroke may simply have been beautiful to see, but too weak to reach more distant receivers with enough energy to identify... on and on...
You're right about station density being a factor... if we had coverage of stations everywhere, 50 km apart, all configured to operate with a range of about 800km, we could likely locate a very high percentage of C-G strokes, as well as expand into processing IC impulses etc, as well as polarity, etc.... that's the weak link in our hobbyist, experimental Locating Network!!!!
Stay Safe!
Mike
OH>... typically on Lightningmaps.org especially, the ACTUAL location of a station on the public maps IS displaced purposely... for 'privacy' reasons.
