Search found 29 matches

by christopher.loughner
August 7th, 2020, 10:33 am
Forum: HYSPLIT for PCs
Topic: meteorology outputs along the trajectory
Replies: 1
Views: 169

Re: meteorology outputs along the trajectory

No. Pressure, potential temperature, ambient temperature, precipitation, mixing depth, relative humidity, specific humidity, water vapor mix ratio, solar radiation, and terrain height are the only variables available for output in a HYSPLIT trajectory run at this time.
by christopher.loughner
August 7th, 2020, 10:00 am
Forum: Dispersion Model
Topic: Concentration output with STILT physics
Replies: 1
Views: 251

Re: Concentration output with STILT physics

Yes. Don't set ICHEM=8 and set which STILT option you would like to use individually in your SETUP.CFG file (i.e., IDSP=2, KBLT=5, KMIXD=3, VSCALES=-1.0, CAPEMIN=-2.0). Note that not setting ICHEM=8 will result in no PARTICLE.DAT and PARTICLE_STILT.DAT files to be produced, which requires CMASS=1.
by christopher.loughner
June 25th, 2020, 4:40 pm
Forum: 1. Installing HYSPLIT
Topic: Access to multi-processor version of HySPLIT
Replies: 2
Views: 115

Re: Access to multi-processor version of HySPLIT

For obtaining HYSPLIT for Linux, see:

https://www.ready.noaa.gov/HYSPLIT_linux.php

There are precompiled linux executables available that are compatible with MPI. Another option is to request the source code for you to compile yourself.
by christopher.loughner
June 25th, 2020, 12:19 pm
Forum: 17. Custom simulations
Topic: Multiple species simulations
Replies: 3
Views: 155

Re: Multiple species simulations

Yes, you can run with multiple species. In the Concentration Setup menu 1) click on the Pollutants, Deposition, and Grids setup button; 2) under pollutant change =1 to =2; and 3) click on specie 1 and specie 2 under pollutant and deposition to configure the emissions rate and deposition properties f...
by christopher.loughner
June 25th, 2020, 10:12 am
Forum: 1. Installing HYSPLIT
Topic: Accidentally saving the setup file during the run
Replies: 2
Views: 107

Re: Accidentally saving the setup file during the run

SETUP.CFG is read at the beginning of the run. Assuming the program already read SETUP.CFG before saving it while it is running, the model simulation should proceed as initially intended.
by christopher.loughner
June 25th, 2020, 10:06 am
Forum: 15. Radioactive pollutants and dose
Topic: Avoid problems with particles reaching the stratosphere
Replies: 3
Views: 123

Re: Avoid problems with particles reaching the stratosphere

For dispersion simulations, particles are reflected off of the model top staying within the modeling domain.

Note that this is not the case for trajectory simulations. A trajectory calculation will stop when it is transported above the model top.
by christopher.loughner
June 25th, 2020, 9:55 am
Forum: 15. Radioactive pollutants and dose
Topic: Avoid problems with particles reaching the stratosphere
Replies: 3
Views: 123

Re: Avoid problems with particles reaching the stratosphere

This is not recommended. Lowering the model top for this scenario will cause pollutants that should be transported into the stratosphere to stay below the model top resulting in a high bias in particle concentrations just below the model top. These particles being prevented from crossing the model t...
by christopher.loughner
June 22nd, 2020, 2:27 pm
Forum: 5. Trajectory options
Topic: Dispersion models - vertical motion methods
Replies: 4
Views: 195

Re: Dispersion models - vertical motion methods

isosigma would cause the trajectory to stay at the same sigma level.
by christopher.loughner
June 22nd, 2020, 10:12 am
Forum: 10. Alternate display options
Topic: 3D visualization of Hysplit output?
Replies: 6
Views: 243

Re: 3D visualization of Hysplit output?

Producing vertical cross-section and maps of trajectories and particle locations in dispersion simulations will be covered in this tutorial. Yes, it is desirable to analyze results in 3D (i.e., is an air pollution plume at the surface where people breathe or aloft?). What is important / interesting ...
by christopher.loughner
June 22nd, 2020, 8:41 am
Forum: 17. Custom simulations
Topic: Code parallelization
Replies: 2
Views: 124

Re: Code parallelization

We do not have a GPU version of HYSPLIT. A group in Australia has worked on porting HYSPLIT to a GPU based code. See: F. Yu, P. Strazdins, J. Henrichs and T. Pugh, "Shared Memory and GPU Parallelization of an Operational Atmospheric Transport and Dispersion Application," 2019 IEEE International Para...