Dock Talk

Anyone interested in viewing the initial data from the GNSS position loggers can head to https://www.2bsailing.ca/cfsa/ (best viewed on a larger screen like a laptop).

We are monitoring the positions of the docks to get an idea of how much movement they have during windy conditions. So far we haven't had any storms matching the one in Nov 2024, so are unable to put an upper bound on the amount of dock movement.

One thing we notice is that the GNSS accuracy drops markedly during solar flare events - distortions of the earth's ionosphere add uncertainty to the signals' timing, and lead to 10+ metre wanderings in the position (we know this from attaching loggers to the rock anchors, which definitely aren't actually moving). Geomagnetic activity is measured with a parameter called Kp and I have recorded this value together with the position data (more details at https://www.swpc.noaa.gov/impacts/space-weather-and-gps-systems). There are GNSS systems that employ ground-based corrections to cancel out these variations, but they are much more expensive than the loggers we are using.

Feel free to play around with the data tool - I'm still tweaking it to help extract useful info. If you have any questions about it, let me know.