all particles go to surface

[CaroMedel]

HI, The following is happening to me with Opendrift: At the first time step all the particles go up to z=0; Sometimes this is fixed by adding the line o.set_config('drift:vertical_mixing', True) , but many times it is not fixed. The z variable (for one particle), looks like this: -8,2322025 0 0 0 0 0

I would like to know what are the possible reasons and solutions for this, i am using OceanDrift module thank you

[CaroMedel]

hi?

[knutfrode]

Hi, It is not clear why this is happening, as the default buoyancy (terminal_velocity) is 0 for particles in OceanDrift. Perhaps you are adding an ocean model which has an upwards ocean current?

Can you make a minimalistic example which reproduces this issue?

[CaroMedel]

The simulation is using the upward ocean current from the hydrodynamic model. Maybe this upward current is too high?

[knutfrode]

That could be. You can disable the vertical advection (due to ocean vertical current, w) with o.set_config('drift:vertical_advection', False)

[CaroMedel]

Thank you