Custom Query (210 matches)

hi there,

I reaslise that in subrountine 'advance.o', all the particles that below the ground are reflected which means they are moved back to the altitude above ground. I could understand this setting for gas, but maybe not for some particles, and it make no sense for my case when I am simulating seed dispersions.

So I would suggest to set up a switch to do reflection or not.

If I want to fix in my own version, could you comment on how to fix it in the most simple way?

Hi there, I am using flexpart-WRF to simulate particel trajectories and what come out seem unnatural and may be casued by some issues.

The altitudes of all particles keep increasing for first 8 hours (10am to 18) and then remain at exactly same altitude for another 16 hours (18-8) before increasing again. The last recorded altituedes are often far off the ground (above 200 m).

I changes my WRF inputdata to different dates and files but it keeps having the same problem. So could you please be possible to advise any potential issue causing this?

Thank you so much for you help and support in advance.

Cheers, Iris

Dear colleagues, It seems that deposition units in output NETCDF files of FLEXPART-WRF are defined erroneously (pg·m-2) while It should be (ng·m-2)

This problem was first noted because of extremely high underestimation of deposition following release scenario as compared to results of simulations of other models. E.g. dry deposition calculated by the RODOS system for the same site, same release scenario and using the same meteorological data was on average by about 3 orders of magnitude higher as compared to FLEXPART results.

The source of potential error was identified by analysis of the FLEXPART code. The variable drygrid2 which is written to output netcdf file is defined in subroutine nc_write_output (source file netcdf_output_mod) as:

drygrid2(ix,jy,kp,nage)=1.e12*drygrid(ix,jy)/area(ix,jy)

Thus converstion to pico- units is done by multiplication on 1E12 factor here. Further inspection of code showed that the variable drygrid is in case of 1 age class and single specie simply equal to the variable drygridunc2, while the latter is defined in time loop when running model in the subroutine drydepokernel:

drygridunc2(ix,jy,ks,kp,nunc,nage)= &

drygridunc2(ix,jy,ks,kp,nunc,nage)+deposit(ks)

Regarding the variable deposit the comment in the same subroutine states that:

! deposit amount (kg) to be deposited Thus final deposition should be in pKg·m-2=ng·m-2.

Attached is file with formulas used for conversion from kg to Bq.