HYSPLIT Forum: hysplitbbs.arl.noaa.gov

If I understand what you are saying correctly, then yes, you are correct. If you define a constant settling velocity for the particle (by specifying the deposition velocity for a 'particulate' computational particle), then you over-ride the calculation and the settling velocity is the value that you...

The PARINIT file basically contains a list of computational particles with their relevant characteristics. (Time, location, mass, etc.) With NINIT=1, HYSPLIT opens the file at the beginning of the simulation and looks for particles with the same time as the run start. If it finds some, then it reads...

Please review the tutorial to understand how changing the particle number affects results.

Section 7 is particularly relevant.
https://ready.arl.noaa.gov/documents/Tu ... _test.html

This section of the tutorial may help you. https://www.ready.noaa.gov/documents/Tutorial/html/chem_linear.html If particle diameter, density, and shape are all 0, then the computational particle is treated as a gas and no gravitational settling is applied, but dry deposition may occur when the compu...

The lat lon coordinate for the HYSPLIT concentration grid is generally the center of the cell (for computational particles on a square concentration grid). Met data output is valid for the point at which it is output. For computational particles which are between met grid points, the met data is int...

Yes - you are exceeding the number of particles / puffs allowed. That is what this warning in the MESSAGE file means. WARNING emspnt: exceeding puff limit WARNING depsus: exceeding puff limit NOTICE main: 168 58515839 10000 2.6298373E+14 WARNING emspnt: exceeding puff limit HYSPLIT will not emit mor...

Thank you for explaining more.
Could you please attach your CONTROL, SETUP.CFG and MESSAGE file.

Are you concerned by the concentration contours not being smooth? Please review the tutorial, in particular this portion. https://www.ready.noaa.gov/documents/Tutorial/html/conc_part.html Increasing the number of particles or making the concentration grid size larger will help. If you still have pro...

Please also see the following documentation for more detail on how meteorological grids should be specified. It can get quite complex! https://www.ready.noaa.gov/hysplitusersguide/S262.htm - Number of input data grids Default: 1 Number of simultaneous input meteorological files. The following two en...

Please use an additional gdas1 file so that there is an overlap in time between the two met datasets. See below for an example. HYSPLIT will automatically use the finer resolution (gdas0p5/ GHDA) during the overlap time. 2 03 01 00 00 1 42.768 -86.149 100.0 -24 0 10000.0 5 /tdir/gdas0p5/ 20120227_gd...