![]() ![]() The Tides and Tidal Currents are NOT in sync with each other. You cannot use one table to predict the other. Such as you can cross that mud bank at high tide but at low tide you will rip the keel off of your boat.Īnd the Current table will give you informed data as to when you can safely transit some area where the currents can wreck your vessel. The Tide table can keep you from running aground in some areas. Keep both Tide & Current Tables on board your boat and learn to use both tables. But in some areas.Transit only during slack water.Safer that way. ![]() This is in accordance to the capabilities of your vessel. ![]() Slack water is inter-changable with Minimum Current in your Current Tables.įor movement throught some areas you should arrive about a half hour before slack water. It is 'Stand of Tide' at either high or low tide when there no change in the height of tide, high or low, for a few moments. and then overlay the influence of wind tides and heavy rains (or 'drought') in the Delaware River basin: can be a 'crap shoot' to get it 'right' to navigate during 'slack'. If you really want to take a look at 'confusion' look at the C&D Canal - influenced by radically out of phase tides and radically different tidal heights of the Chesapeake and Delaware Bays and the 'alteration difference' that occurs in the canal. "Hellgate" in NYC, Barnegat Inlet in NJ and "Hellgate" and Elliott Cut on the AICW in SC are prime examples of the differences between calculated tide tables and 'historic' actual performance data. you will invariably be entering at the WRONG time. If you use 'just a tide calculation program', etc. the proper way to know when to 'shoot' or for 'slack water' is to consult the historic CURRENT tables - such as published in "Eldridge" (East Coat tide and current tables). So, when navigating across especially small inlets with large bays 'behind' the inlet. slow rate of transfer as one cup is filled change the hose to a much larger diameter connection (geometry) and the 'rate of change' becomes 'faster'. influenced tides across such inlets radically changes the current and the timing of the 'slack' conditions in the inlets - no 'prediction' is possible when 'wind tides' overlay across the current in an inlet.Īn example of the restriction geometry: take two styrofoam cups and at equal level connect them 'at the bottom' with a very small tube. All this is not 'calculable' but is rather entirely based on the historical record of exactly how each inlet 'works' and retards the change due to the geometry of the 'restriction'. DIFFERENCE between the tidal heights, not the typical 'half way' (6/12th of the tide range interval) rise or fall of the ocean side tide the 'ocean side' tide being the controlling factor. In all of these situations the max current only occurs at the max. just the opposite during the ebb, max current flow 'out' will be long delayed until max low on the 'ocean side', leaving the tide level somewhat higher on the land side of the inlet - again another 'delay'. ![]() It also means that the tide on the land side of the inlet will be delayed in time due to the 'restricted flow' The tide has to rise BEFORE it starts to flow through an inlet, all due to the 'flow restriction' due to the geometry of the inlet. The classic example for the difference between the two is the filling and ebbing at inlets. ![]()
0 Comments
Leave a Reply. |