Keywords for ramping

Summary

Hi, one thing that is essential for telemac, tomawac, gaia model stability is to gently apply boundary conditions at the start of a run. It seems odd that there are not keywords to do this. So I am proposing we add some. Thoughts welcome, examples below:

Why is this feature useful?

Models often crash if waves are applied without ramping, as do the water levels and discharges.

How to implement it?

In telemac2d/3d PRESCRIBED ELEVATION RAMPING PERIODS = 21600;21600 PRESCRIBED ELEVATION RAMPING INITIAL VALUES = 0;0 PRESCRIBED FLOW RATE RAMPING PERIODS = 21600;21600 PRESCRIBED FLOW RATE RAMPING INITIAL VALUES = 0;0 PRESCRIBED TRACER RAMPING PERIODS = 21600;21600 PRESCRIBED TRACER RAMPING INITIAL VALUES = 0;0

In gaia PRESCRIBED SUSPENDED SEDIMENT RAMPING PERIODS = 21600;21600 PRESCRIBED SUSPENDED SEDIMENT RAMPING INITIAL VALUES = 0;0

In tomawac PRESCRIBED WAVE HEIGHT RAMPING PERIODS = 21600;21600 PRESCRIBED WAVE HEIGHT RAMPING INITIAL VALUES = 0;0

and could also have a method for linear, sinusoidal,etc PRESCRIBED BOUNDARY RAMPING METHOD = 1;2;3

Additional resources

none