[MITgcm-support] help

[Martin Losch]

I have no experience with this, but I think that the extra forcing by the wind (I am guessing that you assume that part of particles stick out of the water and that these “sails" are subject extra wind foring, although I am not quite sure how to imagine that with “microplastic”), should not be added to the drift velocity.

In fact, the u/vVel already contain the effect of wind forcing, so I don’t think that you need to do anything specific to the ptracers package, as long as you assume that your microplastics can be assumed to be “continuous” with a certain concentration.

Martin

> On 5. Sep 2019, at 08:51, Peipei Wu <1755484049 at qq.com> wrote:
> 
> Hi,
> 
> I use the MITgcm model to simulate the transport of microplastics over the global ocean . Wind affects the drift of microplastics on the sea surface. However, the offline input files do not include the wind field.
> 
>  
> I calculate the speed for drift (Udrift and Vdrift) based on UvelFile, VvelFile and wind field data from ECMWF, e.g. one linear solution is Udrift=Uvel+Uwind*0.01, Vdrift=Vvel+Vwind*0.01. Then the uFld(:,:,1) and vFld(:,:,1) in ptracers_integrate.F were replaced by Udrift(:,:) and Vdrift(:,:). The results were not very satisfactory.
> 
>  
> I wonder if I changed the appropriate subroutine? Will the change of uFld and vFld break the conservation relations? I would be greatly appreciated if you could give some suggestions on simulating the drift process of microplastics.
> 
>  
> Thank you, and I look forward to hearing from you.
> 
>  
> Best wishes
> 
>  
> Peipei Wu
> 
> _______________________________________________
> MITgcm-support mailing list
> MITgcm-support at mitgcm.org
> http://mailman.mitgcm.org/mailman/listinfo/mitgcm-support