HYSPLIT Forum: hysplitbbs.arl.noaa.gov

PLEASE HELP!

This is for my final uni thesis. I am SO confused about the difference in the names of the settings of the web-based and desktop version of HYSPLIT.
I am trying to recreate the same output in the web version to verify the output of the desktop version with no success. Firstly, is this possible using the same input parameters, or are they fundamentally different and will therefore have different outputs even with the same inputs?

Secondly, am I correct in my understanding that the desktop version automatically calculates the boundary layer/inversion layer height for the time of dispersion using the meteorological data? From my understanding this height must be input manually into the web version in the setting "top of averaged layer".

More info: I have set the "top of averaged layer" to the boundary layer height at the time on the day (170m) and everything else the same, and get a wildly different result in the desktop version using all the same other input parameters. The desktop setting for "height of model" is set to the default value of 10,000m.

You might want to first compare the CONTROL and SETUP.CFG files used by READY (which you called web-based HYSPLIT) with those produced with your desktop. HYSPLIT runs should be reproducible when the same CONTROL, SETUP.CFG, and meteorological files are used.

I have checked the CONTROL and SETUP files and they appear to be the same.
Can someone answer my original question about the "top of averaged layer" setting?
Should this be set to the boundary layer height for the corresponding time of day, or does Hysplit automatically calculate the boundary layer using the meteorological data?

The description of "Top of averaged layer" in the web application is given by the "more info" tab next to it.
The top of averaged layer is for defining the top level of the concentration grid.

Using the GUI on the desktop version this is the same as setting the "Height of Levels"
https://www.ready.noaa.gov/hysplitusersguide/S313.htm

Using the GUI you could define multiple levels.

So for instance 100m means the concentrations are averaged from ground to 100m.
If you change this number to 200, it would be concentrations averaged from ground to 200m.
So you could get a different number depending on the vertical profile of your concentrations.