How are you monitoring tides and currents?
What methods are people using to monitor their local tidal behaviour. I know of many resources that informs you of the high and low tide. But what about more in depth analysis such as directions of currents, depths, temps are these resources available?
for currents and bathymetry.
for nautical charts (depth).
for water temp.
But I live in SoCal. There is a lot of regional variation in data availability.
For many areas such as the continental US, tidal ranges are much smaller than what we a re used to in Ireland or the UK. Tidal range in Ireland averages 5.5 to 6 metres, UK is up to about 7 metres excluding tidal bores.
* My trusty annual printed tide tables for Ireland. Make sure to check the offsets from the main stations.
* Sailors & fishermen.
* There's a very detailed tidal map computer prediction of the currents around Ireland from the Marine Institute that seems to confirm other sources.
* Tidal maps from South West Cruising Club that are invaluable.
* Marine charts are the single best (but expensive) information source. And usually th eonly source for offshore.
* The annual sailing almanac can be useful for ports and harbours.
* David Walsh (a kayaker, not the well-known journalist who chased Lance Armstrong for 15) wrote a book called Oilean about kayaking around Ireland that was very useful.
* I trust my own experience for the South East. I think it really helps to understand how the tides split around Ireland and the general flows. (Also I think most swimmers don't believe me when I tell them about tidal lag, the difference between high & low water, and slack tide, which not always the same.
I have a bit of a thing about swimmers not learning more about tides and just accepting what is often flawed information, based on a theoretical flat lunar model, taking no account of local factors. I say it because that's what I used to do as a surfer. Ireland, as an island, situated far from the nearest null tidal spot in the west Atlantic, is a very complex tidal location, (as is the UK and the Channel).
Edit: posted before I was finished.
There are data buoys all over the world. Some transmit very basic data, others; tons. I have an ipad app "Aye TIdes XL” which enables me to access this data by clicking on any of these buoys. Blue diamond “T”’s or “push pins” will bring up a a month of tide charts, by clicking any day, you can open a window that contains sine wave info like high and low tide times, sunrise, sunset, nautical twilight, moon cycle, etc. Click on a red diamond “C” and a sine wave chart for for current speed will come up. You can view that info in mph, knots, etc. There are many fewer “C”s on the map than “T”s.
For nautical charts, I love the Navionics HD apps and use them for route planning as well as back up charts for my boat. They are often more detailed than other digital charts available. Knowing how the depths vary is perhaps the most important bit of information one can have to determine where those funky currents might be.
The main factor that isn’t considered when these tide and current prediction charts are made... weather. There are some really great websites that present the wind, surface current, and surface temperatures in almost real time. Search “wind guru” for your area.
I took a few screen shots of these apps, but can’t quite figure out how to post them here. If anyone likes I can send them via e-mail.
...anything worth doing is worth overdoing.
Looks useful Ron. Where are you getting that?
The .gif above is from
It's a flow model of Tampa Bay.
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