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Calculating Gloranthan tides


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I created a simple spreadsheet to calculate the Gloranthan tides that allows estimates of Gloranthan tides depending on the weekday of the Blue Streak added to the influence of the weekly tide that is reflected in the phase of the Red Moon (as visible from Magasta's Pool/Dragon Pass).

There are two parameters that can be played with for different models that you can play with.

The first is the maximum amplitude for the weekly tidal cycle. This value gets multiplied with my estimates of the tidal amplitude of the day of the Lunar week (at the end of the table).

The second parameter is the daily increase of the (isolated) Blue Streak tide. My simple approach is just to increase this by the same amount for every day the Blue Streak takes to climb up the Sky River. 

You start your tidal cycle by deciding on the weekday that had the last fall of the Blue Streak, then you roll 1 D6. Go to the Lunar day of your falling Blue Streak, roll 1D6 and just read the values for the day and go down to the line that shows the D6 result. At the end of the line you will find your next starting date.


Play around with the parameters. If the weekly cycle has a greater factor than the Blue Streak factor, you may end up with a slow outflow despite the Blue Streak still rising. As this has not been described yet, it looks like the Blue Streak factor should be greater than the Weekly Tide factor.

And it is up to you what length unit you assign to the factors. Being used to SI units, I would run with meters.

With factor 1 for the weekly cycle and factor 1.5 for the Blue Streak increase, you get a maximum amplitude of 10. If you make this meters, it corresponds to the tidal changes as mentioned in the scenario "The Sea Cave", if you make this feet, it gives you a tidal variation between average high tide and highest tide of about 4-5 feet, which would be similar to Jeff's difference between High Tide and Highest Tide for the Rightarm Isles (reaching the reeds or almost covering the reeds). But try for yourself.

You can play with the weekly increases or the daily ones to get other variations, like non-linear increases for the Blue Streak, or making small differences for the weekly day heights (as fraction of 1) - ideally with a personal copy of this file.

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This has an obvious tie-in with that Gloranthan astronomy book you haven't written yet!😀

I know the tidal variation can be considerable, but I am no oceanographer and don't know what produces famous RW tidal locations like the Bay of Fundy.  Have you looked into this, and the implications for Gloranthan coastal locations?


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