HYSPLIT Forum: hysplitbbs.arl.noaa.gov

Dear all,

How does HYSPLIT deal with the main impaction mechanisms for very small particles?

Are small scale turbulences leading to impaction?

Your help would be much appreciated. Thanks.


Kind Regards,

Ming

Dear all,

I would like to know more about wind data in NCEP/NCAR Reanalysis.

I am aware that NCEP/NCAR Reanalysis includes the horizontal and vertical components of the three-dimensional wind field.

I am wondering what kind of data is actually recorded in the vertical component of the wind field ...

Dear alicec,

Thank you very much for your reply and help. You have answered my questions. It all makes sense to me now. Thanks.


Kind Regards,

Ming

Dear alicec,

Thanks for your reply and help.

'The initialization will randomly distribute particles over that area.'

If a source (Opt-5) is specified as 600 m2 and the emission rate (Opt-4) is specified as 100 particles/hour (1 particle = 1 mass unit) and the emission duration is 6 hours ...

Dear alicec,

Thank you very much for your reply. Your explanation is very helpful. It all makes sense to me now.

I would like to confirm something about the multiple sources (emission area) with you.

I notice that we are able to specify the size of the source with its emission rate.

3(1)- Enter ...

Dear alicec,

Thanks for your reply.

So the settings for the simulation attached in my previous post are correct?

I am just wondering if NUMPAR is set to be 15,000,000 (1 particle is equivalent to 1 mass unit), but HYSPLIT actually released 9,289,945 particles. What did happen to the missing ...

Dear alicec,

Thank you very much for your help.

I have reduced the number of particles released to 15,000,000 and run some simulations. The sum of each proportion at the different height levels is 100% now, which is good. But I have found another issue.

After 6 hours of emission, the number of ...

Dear alicec,

I have also just run with a smaller number of particles (288,000) and an emission rate of being 9600 on HPC for 6 replications (the same starting time). There was no such problem for all 6 replications, but the outputs and dispersal plumes were slightly different among the 6 ...

Dear alicec,

Thank you very much for your help.

I ran with a smaller number of particles (288,000) and an emission rate of being 9600 on my computer (Windows). There was no such problem. I got 100.01%. Please see below and find the attached control and setup files.

Index Height %Mass
10 2755.0 ...

Dear alicec,

Thank you very much for your help.

I actually ran the simulation on HPC (HYSPLIT for LINUX), due to a large number of particles (28,800,000). It took almost 20 hours to finish.

I have attached my CONTROL and SETUP.CFG file. Please find the attached files. Your help would be much ...