Hi,
I would like to change the emissions of PM2.5, PM10 and VOC for a region using the DESID namelist.
I know how to scale the emissions for simple species (e.g. NH3, NO etc.) but I do not know how to do this for complex species such as PM.
In the user guide, there is kind of example: ```
‘EVERYWHERE’ , ‘ALL’ ,‘PSO4’ ,‘ASO4’ ,‘FINE’,1.0 ,‘UNIT’,‘a’,
‘EVERYWHERE’ , ‘ALL’ ,‘PNH4’ ,‘ANH4’ ,‘FINE’,1.0 ,‘UNIT’,‘a’
Does it mean I should write all PM components individually? Or is there an variable which can gather all PM. I have the same question with VOC.
Regards
Matthieu
Sorry for the delay. If you want to scale all PM components after you’ve added them already, you can use this:
‘EVERYWHERE’ , ‘ALL’ ,‘ALL’ ,‘ALL’ ,‘FINE’, X ,‘UNIT’,‘m’,
to scale the fine-mode components by some factor X. Alternatively if you want to scale coarse PM emissions, you may use:
‘EVERYWHERE’ , ‘ALL’ ,‘ALL’ ,‘ALL’ ,‘COARSE’, X ,‘UNIT’,‘m’,
Be sure to check your log files for the text output of the emission scaling parameters. This is a relatively complicated feature and you’ll want to confirm it is doing what you intend.
Thank you very much. I suppose these lines will impact all PM emissions, even natural PM (e.g sea salt). Is there a possibility to limit this change in emissions to only anthropogenic emissions?
One issue to remember though, if the members of the VOC chemical family you define have names that you find on the emission input files, then you should put the ‘VOC’ label in the Emission Species field and use ‘ALL’ in the CMAQ-Species field:
‘EVERYWHERE’ , ‘ALL’ ,‘VOC' ,‘ALL’ ,‘GAS’, X ,‘UNIT’,‘m’,
If on the other hand, the names of the VOC family members you set up are consistent with CMAQ species names, then do the reverse:
‘EVERYWHERE’ , ‘ALL’ ,‘ALL' ,‘VOC’ ,‘GAS’, X ,‘UNIT’,‘m’,
Thank you for your answer. Now I have a few questions:
The “EVERYWHERE” and “ALL” Stream labels are already defined in the MAQ_Control_DESID_cb6r5_ae7_aq.nml file. In my simulation, I have set up labeled regions such as “M1” and labeled emission streams such as “S1”. When I simulate, I specifically want to adjust the emission scale for a marked area or a certain kind of source. If I scale this particular labeled region or kind of sources, what about the other sources? Do I need to define each tag area and each source class in the MAQ_Control_DESID_cb6r5_ae7_aq.nml file? Or I scaled after the default setting?
Hope to get your reply
Best
pbwang
I’m not sure I fully understand your question, so I apologize if this answer doesn’t cut it.
The main thing to understand about DESID rules is that they are implemented in the order they are added to the Control file. My typical approach is to use the default rules first that apply to ‘EVERYWHERE’ and ‘ALL’ streams so that every species has the correct baseline emissions.
Then I add rules that target specific regions (e.g. M1) or streams (e.g. S1). If I need to increase emissions, I will typically use the ‘a’ (i.e. add) operator or the ‘m’ (i.e. multiply) operator. If I need to completely change the emissions in an area and/or for a stream, I will use the ‘o’ (i.e. overwrite) operator. When these rules are applied to specific regions and/or streams, the emissions for the other areas will be left at the baseline specified by the default rules.
Does that (admittedly long-winded) answer help? I’m happy to help craft an example set of rules if you have a specific configuration that you are trying to achieve.
