<p>If you use FLEXPART or HYSPLIT, you will essentially be modeling dispersion of the SO2 emissions.  I believe FLEXPART has deposition, but there won't be any chemical reactions or other sources of SO2 in the model simulations using FLEXPART or HYSPLIT.  Furthermore, they aren't meteorological models in themselves so you will need to provide those conditions (e.g. from a WRF simulation).  Comparing WRF-CHEM to a dispersion model is a bit like comparing a jet engine to a bicycle.  WRF-CHEM incorporates emissions from all sources in the region and numerically calculates meteorology and chemistry together as a coupled modeling system.  It can take years to properly learn, setup, and simulate scenarios for a WRF-CHEM project.  On the other hand, dispersion models are relatively easy to install and use.</p>
<p>In general, if you are only looking at volcanic emissions, then a dispersion model should be fine.  But if you want to model the interaction of atmospheric SO2 amongst all sources (e.g. anthropogenic and natural), then a gridded modeling system like WRF-CHEM would be needed.  You could also use WRF with CAMx or CMAQ to accomplish the same thing.  If you are looking to do something more global, then perhaps GEOS-CHEM would be of more interest.</p>
<p>My guess would be that a dispersion model will work fine for all the transport-related questions, but if you want to do anything rigorous for deposition it would likely require a gridded model that does chemistry.</p>
<p>I highly suggest you collaborate with an academic or government modeling group for this project.  Atmospheric models are very complex and collaborative guidance from others can be very valuable.</p>

CC BY-SA 4.0
2024-11-01T02:10:34.477Z
Thank you so much for the comments and suggestions! The lab I am a part of uses ENVI-met for most of our projects and, as far as I know, this is the first time that we'd be working on volcanic emissions. Most of our projects were focused on urban pollutants, which is why ENVI-met was enough. In any case, since I'm expected to produce some results in a year or so, would doing some "preliminary" studies using FLEXPART and HYSPLIT while learning WRF Chem be reasonable? I will also be following your advice of looking for collaborators in the academe or government.
J. Velonta
CC BY-SA 4.0
2024-11-01T03:40:35.630Z
I would start here:  https://www.ready.noaa.gov/HYSPLIT.php  where you can run HYSPLIT on-the-fly using NOAA's archived meteorology.  You might see if you can collaborate with a group that already has WRF-CHEM installed, it is a beast.
f.thorpe
CC BY-SA 4.0
2024-10-31T16:31:55.190Z
2024-10-31T22:33:30.840Z
2024-10-31T22:33:30.840Z
f.thorpe
<p>I am a graduate student and, as part of my research, I am trying to investigate the dispersion and track of volcanic <span class="math-container">$SO_2$</span> injected into the atmosphere during volcanic eruptions and the influence of the Coriolis effect, the intertropical convergence zone, wet and dry deposition, and other such relevant factors on said transport. So far, I've narrowed down the models which I could use to these three:</p>
<ol>
<li>WRF - Chem</li>
<li>HYSPLIT</li>
<li>FLEXPART</li>
</ol>
<p>There are researches on the dispersion of <span class="math-container">$SO_2$</span> in the atmosphere done using all three models, but the WRF Chem seems to be the most commonly used. I'd like to ask if there is an underlying reason for this?</p>
<p>As far as I know (which is very little, admittedly), FLEXPART seems to be just a little less complex than WRF-Chem when it comes to dispersion simulation, and FLEXPART is easier to use due to it having a GUI as well as readily available pre-processed &quot;initial&quot; data provided by the NOAA.</p>
<p>Any insight or advice would be helpful. Feel free to recommend other models for consideration also. Cheers!</p>

CC BY-SA 4.0
2024-10-31T17:54:59.603Z
Welcome to Earth Science SE! I'm not a modeler, but I have a few papers on volcanic SO2 dispersion in my bibliography, I've just had a look: one is using CMIP5, one ECHAM-HAMMOZ, another one GEOSCCM, and yet another one NAME from the UK Met Office. I suppose you've already ruled them out when you narrowed you search?
Jean-Marie Prival
CC BY-SA 4.0
2024-11-01T00:59:13.100Z
Thank you for the suggestions! I've heard of these models but I have not ruled them out yet, per se. I have just not found studies using them. Will look for those and see if I could find some inspiration. Once again, thank you!
J. Velonta
<volcanology><atmosphere-modelling><atmospheric-chemistry>
What would be a good numerical model to simulate the transport of SO2 in the atmosphere?
J. Velonta
# What would be a good numerical model to simulate the transport of SO2 in the atmosphere?

(Asked by: username_0 on 2024-10-31)

I am a graduate student and, as part of my research, I am trying to investigate the dispersion and track of volcanic $SO\_2$ injected into the atmosphere during volcanic eruptions and the influence of the Coriolis effect, the intertropical convergence zone, wet and dry deposition, and other such relevant factors on said transport. So far, I've narrowed down the models which I could use to these three:

1. WRF - Chem
2. HYSPLIT
3. FLEXPART

There are researches on the dispersion of $SO\_2$ in the atmosphere done using all three models, but the WRF Chem seems to be the most commonly used. I'd like to ask if there is an underlying reason for this?

As far as I know (which is very little, admittedly), FLEXPART seems to be just a little less complex than WRF-Chem when it comes to dispersion simulation, and FLEXPART is easier to use due to it having a GUI as well as readily available pre-processed "initial" data provided by the NOAA.

Any insight or advice would be helpful. Feel free to recommend other models for consideration also. Cheers!

**Tags:** volcanology, atmosphere-modelling, atmospheric-chemistry

> **Comments:**
> **username_1**: Welcome to Earth Science SE! I'm not a modeler, but I have a few papers on volcanic SO2 dispersion in my bibliography, I've just had a look: one is using CMIP5, one ECHAM-HAMMOZ, another one GEOSCCM, and yet another one NAME from the UK Met Office. I suppose you've already ruled them out when you narrowed you search?  
> **username_0**: Thank you for the suggestions! I've heard of these models but I have not ruled them out yet, per se. I have just not found studies using them. Will look for those and see if I could find some inspiration. Once again, thank you!  

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## 1 answers

### Answer by username_2 on 2024-10-31. Score: 3 | Accepted answer

If you use FLEXPART or HYSPLIT, you will essentially be modeling dispersion of the SO2 emissions. I believe FLEXPART has deposition, but there won't be any chemical reactions or other sources of SO2 in the model simulations using FLEXPART or HYSPLIT. Furthermore, they aren't meteorological models in themselves so you will need to provide those conditions (e.g. from a WRF simulation). Comparing WRF-CHEM to a dispersion model is a bit like comparing a jet engine to a bicycle. WRF-CHEM incorporates emissions from all sources in the region and numerically calculates meteorology and chemistry together as a coupled modeling system. It can take years to properly learn, setup, and simulate scenarios for a WRF-CHEM project. On the other hand, dispersion models are relatively easy to install and use.

In general, if you are only looking at volcanic emissions, then a dispersion model should be fine. But if you want to model the interaction of atmospheric SO2 amongst all sources (e.g. anthropogenic and natural), then a gridded modeling system like WRF-CHEM would be needed. You could also use WRF with CAMx or CMAQ to accomplish the same thing. If you are looking to do something more global, then perhaps GEOS-CHEM would be of more interest.

My guess would be that a dispersion model will work fine for all the transport-related questions, but if you want to do anything rigorous for deposition it would likely require a gridded model that does chemistry.

I highly suggest you collaborate with an academic or government modeling group for this project. Atmospheric models are very complex and collaborative guidance from others can be very valuable.

> **Comments:**
> **username_0**: Thank you so much for the comments and suggestions! The lab I am a part of uses ENVI-met for most of our projects and, as far as I know, this is the first time that we'd be working on volcanic emissions. Most of our projects were focused on urban pollutants, which is why ENVI-met was enough. In any case, since I'm expected to produce some results in a year or so, would doing some "preliminary" studies using FLEXPART and HYSPLIT while learning WRF Chem be reasonable? I will also be following your advice of looking for collaborators in the academe or government.  
> **username_2**: I would start here:  https://www.ready.noaa.gov/HYSPLIT.php  where you can run HYSPLIT on-the-fly using NOAA's archived meteorology.  You might see if you can collaborate with a group that already has WRF-CHEM installed, it is a beast.  

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