HYSPLIT Forum: hysplitbbs.arl.noaa.gov

It was suggested that the trajectory of wind is different from trajectory of concentrations. Is this because properties of a certain chemical comes into play? What is causing the difference?

I assume you talking about the difference in the trajectory calculation vs. the center of mass trajectory calculation shown in section in Section 7.6 number 3.

One of the big reasons they can be different is because of wind shear - the variation of wind speed and direction with height. Dispersion will transport material to different heights of the atmosphere where it will encounter different mean wind conditions. This will result in the center of mass of the plume having a different trajectory than a simple trajectory released from the same location.

So far we have not modeled any chemical transformations, deposition, or gravitational settling which would be dependent on the properties of the substance you are modeling.
We will get to differences caused by those things in later sections (Section 11, 15, 14, 16).

Thank you. Wish there was a like button but there isn't. Or is there?