Ah if I only had a dime for every station people asked me to add. I'd make a small down payment on a car :)

The short answer to the question "why don't you have my station?" is because of copyright issues that started with the UK Hydrology Office and sparked what I call "The Great Purge". The UKHO demanded we remove all Admiralty-derived tide harmonics because they claimed copyrights on them, even though they'd been published for years by the French in what appeared to XTIDE and to me to be a copyright-free government document. But we couldn't win our arguments with them (and boy did we try) so Dave Flater of XTIDE pulled all the stations out of the database.

Why did they demand we pull the data? Money, my friend, money. If you give them enough (and keep giving it every year) they'll give you a license for the harmonics. Without the money, no access. It does seem to me to be a pigheaded approach, as accurate tide information is (to me!) a necessary safety item that should be given out freely, or people may well die. I guess the UKHO does not care about that, because they refused all of our approaches to license their data. I guess they refused, since they never responded to any of our emails. Dave Flater said, and I concurred, that this was obviously a waste of our time trying to pursue this; we were not going to win no matter what. Sometimes you have to pick your battles, and this was one that was already decided against us. Sigh.

Unfortunately, that attitude is spreading around the world. Australia is another country that's restricting or not publishing their latest harmonics, and any program that uses the XTIDE harmonics is slowly drifting off. There's nothing to be done either, we can't get the new harmonics from them and that's that.

So why, you ask, are there stations from the UK? Because a helpful group in England with tidal data provided it to Dave and he created the harmonics from that data. Alas, all we have are those stations in the UK, and none in Ireland. A sad state of affairs, indeed.

What this does say is that with enough data, Dave can create copyright-free harmonics for that location. It is somewhat magic, but there are programs out there on the XTIDE web site that will do this. The trouble is, he need 8+ years of tides in order to get good accuracy, and very few groups have that much data they're willing to share with him.

What can you do? Well, the only thing I can think of, is if you live in a country that won't publish, or won't allow free use of, their harmonics to write to them and demand an explanation of why they treat safety of people so callously. Not all of us have web access at sea, so we can't get the tide tables that way, so a program like the Tide Widget or XTIDE, that sits on your computer and is always available, can be a matter of life or death. Maybe if enough people complain, something can be done.

Not that I would hold my breath, though.

August Hahn, 11 May 2006